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Research Paradigms – Howard E. Zimmerman

The page may be of use to Editors wanting References.

The Photochemical Research Items are the ones which led to the Porter Medal Award (2006) and many of the the Non-Photochemical Items led to the ACS James Flack Norris and Hilldale Awards. Note the description below.

There are 29 topics, some of which are already partially covered in Wikipedia, but most often with incomplete coverage and with incomplete referencing. The topics not already somewhere in Wikipedia are ones which should be.

This listing with very brief summaries and then references needs to be expanded and will take some work. But for now, at least a complete literature search is provided with a main source.

The section after this is a more complete listing but only of literature references.

Organic Chemical Items; Brief Outlines and References – Theory, Mechanisms and Analyses Currently Utilized

Introduction of QM theory relating photoreactivity to excited state structure in 1961

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Until these first efforts there were no reasonable photochemical mechanisms. The problem was that organic chemists were not knowledgeable in quantum mechanics and the physical chemists didn't know organic chemistry. It was the author's good luck to be active in both areas. Thus the real reactants in photochemistry are the excited states, and it was shown how excited state structures would lead to mechanisms for most of the known photochemical processes.

<28>. "A Mechanistic Approach to Organic Photochemistry", Zimmerman, H. E. Seventeenth National Organic Symposium of the American Chemical Society, Abstracts, Bloomington, Indiana, 1961, pp 31–41.

<30>. "Mechanistic Organic Photochemistry. IV. Photochemical Rearrangements of 4,4-Diphenylcyclohexadienone", Zimmerman, H. E.; Schuster, D. I. Journal of the American Chemical Society, 1962, 84, 4527–4540.

<35>. "A New Approach to Mechanistic Organic Photochemistry", Zimmerman, H. E. in Advances in Photochemistry, Editors: A. Noyes, Jr., G. S. Hammond and J. N. Pitts, Jr., Interscience, Vol. 1, 183–208, 1963.

Elucidation of the stereochemistry of ketonization of enols and kinetic protonation

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A very large number of organic reactions proceed via enolic intermediates and many of these bear an alpha substituent and thus, a priori, can afford two diastereomers. If one knows the stereochemistry of ketonization of these enolic intermediates, then one can predict the stereochemistry of a myriad of organic reactions. It was proposed in 1955 by the present writer that the kinetic protonation of enolic species proceeds with an early transitions state with the alpha carbon being close to sp2 hybridized. The proton donor selectively approaches the less hindered face of the enolate, thus leading to the less stable of two diastereomers. Reactions controlled in this fashion include (a) decarboxylation of malonic acids, (b) decarboxylation of beta-keto acids, (c) the Michael addition of nucleophiles to unsaturated carbonyl compounds, (d) the Birch reduction of enones, (e) the deprotonation – protonation of carbonyl compounds, (f) the dehalogenation of alpha-haloketones, (f) the Norrish Type II Reaction, and many more.

<7>. "The Stereochemistry of the Ketonization Reaction of Enols", Zimmerman, H. E. Journal of Organic Chemistry, 1955, 20, 549–557.

<12>. "The Stereochemistry of Ketonization. IV", Zimmerman, H. E. Journal of the American Chemical Society, 1957, 79, 6554–6558.

<9>. "The Stereochemistry of the Ketonization Reaction of Enols. III", Zimmerman, H. E.; Giallombardo, H. J. Journal of the American Chemical Society, 1956, 78, 6259–6263.

<20>. "The Stereochemistry of Ketonization. X. Enols from Haloacids", Zimmerman, H. E.; Cutshall, T. W. Journal of the American Chemical Society, 1959, 81, 4305–4308.

<200>. "Enhanced Endo-Exo Selectivity in the Stereochemistry of Ketonization of Enols", Zimmerman, H. E.; Linder, L. W. Journal of Organic Chemistry, 1985, 48, 1637–1646.

<210>. "Kinetic Protonation of Enols, Enolates and Analogs; The Stereochemistry of Ketonization", Zimmerman, H. E. Accounts of Chemical Research, 1987, 20, 263–268.

<280>. "The Stereochemistry of Allenic Enol Tautomerism; Independent Generation and Reactivity", Zimmerman, H. E.; Pushechnikov, A., European Journal of Organic Chemistry, 2006, 15 3491–3497.

The commonly accepted chair transition state ("Zimmerman-Traxler") for aldolization

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It was in 1957 that this transition state was proposed for aldolization and related reactions. The basic premise is that the cation of a nucleophilic species, such as an enolate, initially is ion-paired with the enolate oxygen. At the end of the reaction that cation is paired with the oxygen of the carbonyl group which has been attacked by the enolate. But at mid-reaction the cation is bonded to both oxygens. The six-membered species is in a chair conformation. The lowest energy conformation leads to product and the concept permits one to predict the reaction stereochemistry. This concept was applied to aldolization, the Reformatsky reaction, the Ivanov reaction, etc.

<10>. "The Stereochemistry of the Ivanov and Reformatsky Reactions. I", Zimmerman, H. E.; Traxler, M. D. Journal of the American Chemical Society, 1957, 79, 1920–1923.

<17>. "Overlap Control of Carbanionoid Reactins. II. Stereochemistry of the Perkin and Related Condensation Reactions", Zimmerman, H. E.; Ahramjian, L. Journal of the American Chemical Society, 1959, 81, 2086–2091.

Meta electron transmission in excited states

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In 1963 It was noted that in excited states of aromatic compounds with electron donating or withdrawing substituents, electron transmission is meta in contrast to the normal ortho-para transmission characteristic of ground state chemistry. The initial experimental observation derived from the efforts of Egbert Havinga who commented that there was no rationale in current resonance theory. The work of the writer provided the molecular orbital rationale as well as experimental examples with electron donors and electron withdrawing groups. This early work used Hückel computations available at the time. More recently much more sophisticated computations have confirmed the early efforts, revealing both energetic effects and conical intersections.

<31>. "Mechanistic Organic Photochemistry. II. Solvolytic Photochemical Reactions", Zimmerman, H. E.; Sandel, V. R. Journal of the American Chemical Society, 1963, 85, 915–922.

<32>. "Mechanistic Organic Photochemistry. III. Excited State Solvolyses", Zimmerman, H. E.; Somasekhara, S. Journal of the American Chemical Society, 1963, 85, 922–927.

<238>. "The Meta Effect in Organic Photochemistry; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E., Journal of the American Chemical Society 1995, 117, 8988–8991

<249>. "The Ortho-Meta Effect in Organic Photochemistry; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E., Journal of Physical Chemistry, 1998, 102 5616–5621.

The Di-pi-Methane Rearrangement (discovery & mechanism)

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This rearrangement was originally encountered the in photolysis of barrelene to give semibullvalene. Once the mechanism was recognized, it was clear that the structural requirement was having two  groups attached to an sp3-hybridized carbon, and then a variety of further examples was obtained. One was the photolysis of the "Mariano Compound", 1,1,5,5- tetraphenyl-1,4-pentadiene.

<60>. "Mechanistic Organic Photochemistry. XXIV. The Mechanism of the Conversion of Barrelene to Semibullvalene. A General Photochemical Process", Zimmerman, Binkley, R. W.; Givens, R. S.; Sherwin, M. A. Journal of the American Chemical Society, 1967, 89, 3932–3933.

<80>. "The Di-pi-Methane Rearrangement. Interaction of Electronically Excited Vinyl Chromophores. Zimmerman, H. E.; Mariano, P. S. Journal of the American Chemical Society, 1969, 91, 1718–1727.

<95>. "The Di-pi-Methane Rearrangement of Naphthobarrelenes. Mechanistic and Exploratory Organic Photochemistry. L", Zimmerman, H. E.; Bender, C. O. Journal of the American Chemical Society, 1970, 92, 4366–4376.

<96>. "Unsymmetrical Substitution and the Direction of the Di-pi-Methane Rearrangement; Mechanistic and Exploratory Organic Photochemistry. LVI", Zimmerman, H. E.; Pratt, A. C. Journal of the American Chemical Society, 1970, 92, 6259–6267.

<103>. "Electron Delocalization as a Controlling Factor in the Di--Methane Rearrangement. Exploratory and Mechanistic Organic Photochemistry. LXII, Zimmerman, H. E.; Baum, A. A. Journal of the American Chemical Society, 1971, 93, 3646–3653.

<104>. "Competitive Photochemical Pathways in the Di-pi-Methane Rearrangement. Exploratory and Mechanistic Organic Photochemistry. LXIII", Zimmerman, H. E.; Hackett, P.; Juers, D. F.; McCall, J. M.; Schröder, B. Journal of the American Chemical Society, 1971, 93, 3653–3662.

<113>. "The Stereochemistry of the Di-pi-Methane Rearrangement; Mechanistic and Exploratory Organic Photochemistry. LXIX", Zimmerman, H. E.; Baeckstrom, P.; Johnson, T.; Kurtz, D. W. Journal of the American Chemical Society, 1972, 94, 5504–5505.

<114>. "An Unexpected Sigma Plus Pi Rearrangement of a Di-pi-Methane Reactant. Inhibition of the Di-pi-Methane Rearrangement. Mechanistic and Exploratory Organic Photochemistry. LXX", Zimmerman, H. E.; Pincock, J. A. Journal of the American Chemical Society, 1972, 94, 6208–6209.

<129>. "The Di-pi-Methane and Oxa-di-pi-Methane Rearrangements", Hixson, S. S.; Mariano, P. S.; Zimmerman, H. E. Chemical Reviews, 1973, 73, 531–551.

<282>. "Five Decades of Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E., Pure and Applied Chemistry, 2006, 2193–2203. Porter Award Address.


The Möbius-Hückel (M-H) Concept for reaction allowedness and forbiddeness

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One year following the Woodward-Hoffmann and Longuet-Higgins publications, the present author noted that both transition states and stable molecules sometimes involved a Möbius array of basis orbitals. In these there is an odd number of plus-minus sign inversions in proceeding around the cycle. A circle mnemonic was advanced which provides the MO energies of the system; this was the counterpart of the Frost-Musulin mnemonic for ordinary Hückel systems. It was noted that 4N electrons is the preferred number for Möbius moieties in contrast to the common 4N+2 electrons for ordinary Hückel systems. Edgar Heilbronner had described twisted annulenes which had Möbius topology, but in including the twist of these systems, he concluded that Möbius systems could never be lower in energy than the Hückel counterparts. In this research it was noted that along the reaction coordinate of pericyclic processes one could have either a Möbius or a Hückel array of basis orbitals. With 4N or 4N+2 electrons, one is then led to a prediction of allowedness or forbiddeness. Additionally, the M-H mnemonics give the MO's at part reaction. At each degeneracy there is a crossing of MO's. Thus one can determine if the highest occupied MO becomes anti-bonding with a forbidden reaction resulting. Finally, the M-H parity of sign inversions was utilized in the 1970 W-H treatment of alloweness-forbiddeness. The parity of sign inversions between bonds and atoms was used in place of the M-H use of atoms; the two approaches are equivalent.

<47>. "On Molecular Orbital Correlation Diagrams, the Occurrence of Möbius Systems in Cyclization Reactions, and Factors Controlling Ground and Excited State Reactions. I", Zimmerman, H. E. Journal of the American Chemical Society, 1966, 88, 1564–1565.

<48>. "On Molecular Orbital Correlation Diagrams, Möbius Systems, and Factors Controlling Ground and Excited State Reactions. II", Zimmerman, H. E. Journal of the American Chemical Society, 1966, 88, 1566–1567.

<106>. "The Möbius-Hückel Concept in Organic Chemistry. Application to Organic Molecules and Reactions", Zimmerman, H. E. Accounts of Chemical Research, 1971, 4, 272–280.

The Grovenstein-Zimmerman Carbanion Rearrangement

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We described a number of anionic rearrangements in which an aryl group migrates from a carbon to the adjacent carbon. Phenyl groups were shown to migrate in preference to aryl groups with para electron donors and alkyl groups were shown not to migrate. The presence of further phenyl groups on the originating carbon was shown to enhance the reaction.

<25>. "Carbanion Rearrangements. II", Zimmerman, H. E.; Zweig, A. Journal of the American Chemical Society, 1961, 83, 1196–1213.

The first correlation diagram for an organic reaction and its relation to reactivity (1961)

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In our study of carbanion rearrangements (the previous item above), the first organic correlation diagram was obtained using Hückel computations. When an occupied bonding MO becomes anti-bonding the reaction is impeded. It was shown that in the carbanion rearrangement, the highest occupied MO became anti-bonding to various extents which controlled the reaction rate. For a methyl group the effect is large enough to preclude methyl migrations.

<25>. "Carbanion Rearrangements. II", Zimmerman, H. E.; Zweig, A. Journal of the American Chemical Society, 1961, 83, 1196–1213.

MO Following– a qualitative MO Counterpart of Electron Pushing

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A method based purely on nodal properties permits construction of correlation diagrams in absence of symmetry. As a reaction proceeds, one can monitor changes in the MO's. The Accounts publication also dealt with sign changes as one goes around a conical intersection.

<119>. "MO Following. The Molecular Orbital Counterpart of Electron Pushing", Zimmerman, H. E. Accounts of Chemical Research, 1972, 5, 393–401.

The current definitions of and distinction between stereoselectivity and stereospecificity

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This came from definitions in 1959 (cited by Ernie Eliel in his text.

<16>. "Overlap Control of Carbanionoid Reactions. I. Stereoselectivity in Alkaline Epoxidation", Zimmerman, H. E.; Singer, L.; Thyagarajan, B. S. Journal of the American Chemical Society, 1959, 81, 108–116 (footnote 16). Note also Ernest Eliel's text.

The correct mechanism of the Birch Reduction accounting for its regioselectivity

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The original Birch mechanism suggested that the initial radical anion protonation was meta and the last step was ortho. Using simple Huckel computations in 1961 we showed this to be incorrect and reversed. After decades of controversy, we devised an esoteric experimental test and showed that our suggested mechanism was correct. Additionally, in this 1990 publication we reported computational support for the initial ortho protonation. This now accepted in textbooks.

<27>. "Orientation in Metal Ammonia Reductions", Zimmerman, H. E., Tetrahedron, 1961, 16, 169–176.

<228>. "Regioselectivity of the Birch Reduction", Zimmerman, H. E.; Wang, P. A., Journal of the American Chemical Society, 1993, 115, 2205–2216.

The free-rotor effect for energy dissipation of electronic excitation

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In Di-pi-Methane studies, it was found that those reactants which had a pi-bond capable of rotation were unreactive as triplets. In these studies it was shown that free-rotation of the triplet provides a main mechanism of energy dissipation with intersystem crossing to ground state.

<88>. "Organic Photochemistry. LIV. Concertedness, Stereochemistry, and Energy Dissipation in the Di-Methane Rearrangement. Source of Singlet-Triplet Reactivity Differences", Zimmerman, H. E.; Pratt, A. C. Journal of the American Chemical Society, 1970, 92, 1409–1411.

<96>. "Unsymmetrical Substitution and the Direction of the Di--Methane Rearrangement; Mechanistic and Exploratory Organic Photochemistry. LVI", Zimmerman, H. E.; Pratt, A. C. Journal of the American Chemical Society, 1970, 92, 6259–6267.

Polarizability predictions of organic reactions

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Using Weinhold bond orbitals as a basis and developing the mathematics for bond-bond polarizability, in a study co-authored with Frank Weinhold, we showed how one could predict in organic chemistry which bonds would be weakened and which would tend to form – on stretching one individual bond. The results were in accord with a variety of organic reactions. This theory now in embodied in the Weinhold NBO analysis.

<230>. "Use of Hückel Methodology With Ab Initio Molecular Orbitals; Polarizabilities and Prediction of Organic Reactions", Zimmerman, H. E.; Weinhold, F. Journal of the American Chemical Society, 1994, 116 1579–1580.

Development of quantitative theories of solid-state reactivity

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For a century it had been recognized that photolyis most often affords different products than the corresponding thermal reaction. The Cohen-Schmidt rationalization noted that a reacting molecule would be surrounded by neighbors which then constituted a cavity which affects reactivity; however, this was qualitative. Using X-ray coordinates we devised the "Quantitative Cohen-Schmidt Cavity". For a large number of solid-state reactions, we computationally extracted one reactant molecule and replaced it by alternative first-intermediates. Invariably, the lowest energy resulting crystal led to the observed photochemical product. Molecular mechanics was used to assess "fit".

<217>. "Confinement Control in Solid State Photochemistry; Photochemistry in a Box", Zimmerman, H. E.; Zuraw, M. J., Journal of the American Chemical Society, 1989, 111, 2358–2361.

<237>. "General Theoretical Treatments of Solid-State Photochemical Rearrangements; And, A Variety of Contrasting Crystal Versus Solution Photochemistry", Zimmerman, H. E.; Zhu, Z., Journal of the American Chemical Society 1995, 117, 5245–5262.

<257>. "Experimental and Theoretical Host-Guest Photochemistry; Control of Reactivity with Host Variation and Theoretical Treatment With a Stress Shaped Reaction Cavity; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Alabugin, I. V.; Smolenskaya, V. N, Tetrahedron, Symposium-in-Print, 2000, 6821–6831.

The Inert Gas Cavity

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Computationally annihilating all atoms of surrounding molecules, retaining only the nearest, and converting hydrogens to heliums, carbons and oxygens and nitrogens to neons – led to an "inert gas cavity imbedding a reactant molecule". These proved susceptible to ab initio computations. Again the lowest energy species led to the experimentally observed product. The agreement with molecular mechanics predictions, which do not include electronics, makes clear that solid state reactivity is sterically controlled. If a transition state cannot fit into the quantitative cavity, electronic favorability cannot lead to reaction.

<250>. "Ab Initio Computations of Reacting Species in Crystal Lattices; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Sebek, P.; Zhu, Z., Journal of the American Chemical Society, 1998, 120, 8549–8550.

<257>. "Experimental and Theoretical Host-Guest Photochemistry; Control of Reactivity with Host Variation and Theoretical Treatment With a Stress Shaped Reaction Cavity; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Alabugin, I. V.; Smolenskaya, V. N, Tetrahedron, Symposium-in-Print, 2000, 6821–6831.

<263>. "Development of Experimental and Theoretical Crystal Lattice Organic Photochemistry; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Nesterov, E. E., Accounts of Chemical Research, 2002, 20, 77–85.

<274>. "A Theoretical Approach to Solid State Organic Photochemistry; Mechanistic and Exploratory Organic Photochemistry", Howard E. Zimmerman, in Computational Photochemistry, Ed. A. Kutateladze, Chapter 1, pp 1–40, CRC (Taylor & Francis), New York, 2005. Vol 13 in Molecular and Supramolecular Photochemistry

<276>. "Development of Theory with Computation", Howard E. Zimmerman, in Computational Photochemistry, Part of a Series titled Theoretical Computational Chemistry, Chap 8, pp 255–278, Ed. M. Olivucci, Elsevier, London, 2005.

<250>. "Ab Initio Computations of Reacting Species in Crystal Lattices; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Sebek, P.; Zhu, Z., Journal of the American Chemical Society, 1998, 120, 8549–8550.

Evidence on the relative roles of conical intersections and energy barriers in photochemistry

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As early as 1961 avoidance of excited state energy barriers was noted to be a major controlling factor in determining the course of photochemical reactions. Subsequently, in 1966, 1972 and in subsequent years conical intersections were depicted as how singlet excited states eventually get to ground state products. In this period and in Chapters edited by Ernie Davidson and Andrei Kutateladze the two-fold control was noted.

<46>. "The Chemistry of Barrelene. III. A Unique Photoisomerization to Semibullvalene", Zimmerman, H. E.; Grunewald, G. L. Journal of the American Chemical Society 1966, 88, 183–184.

<48>. "On Molecular Orbital Correlation Diagrams, Möbius Systems, and Factors Controlling Ground and Excited State Reactions. II", Zimmerman, H. E. Journal of the American Chemical Society, 1966, 88, 1566–1567.

<248>. "Some Theoretical Applications to Organic Chemistry", in Modern Electronic Structure Theory and Applications in Organic Chemistry, Zimmerman, H. E., World Scientific Publishing Co., Ed. E. Davidson. 1998.

<249>. "The Ortho-Meta Effect in Organic Photochemistry; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E., Journal of Physical Chemistry, 1998, 102 5616–5621.

<275>. "Some Theoretical Applications to Organic Photochemistry; Excited State and Open Shell Examples", Howard E. Zimmerman, Chapter VIII in Computational Photochemistry, Zimmerman, H. E., Ed. A. Kutateladze, pp 477–510, Marcel-Dekker, New York, 2005.

Crystal lattice reactivity proceeds in discrete stages with unique reactions in each stage

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A new general phenomenon was uncovered wherein solid–state photochemical reactions were found frequently to proceed in discrete stages with a phase change interposed. The products of State 2 generally differ from those of Stage 1 and provide products most often not obtainable in any other fashion. This provides a powerful synthetic tool.

<263>. "Development of Experimental and Theoretical Crystal Lattice Organic Photochemistry; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Nesterov, E. E., Accounts of Chemical Research, 2002, 20, 77–85.

<264>. "Quantitative Cavities and Reactivity in Stages of Crystal Lattices; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Nesterov, E. E. Journal of the American Chemical Society 2002, 124, 2818–2830.

<274>. "A Theoretical Approach to Solid State Organic Photochemistry; Mechanistic and Exploratory Organic Photochemistry", Howard E. Zimmerman, in Computational Photochemistry, Ed. A. Kutateladze, Chapter 1, pp 1–40, CRC (Taylor & Francis), New York, 2005. Vol 13 in Molecular and Supramolecular Photochemistry

Dissection of triplet-singlet SOC into hybrid pair contributions

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By modification of the spin-orbit coupling programming in Gamess, using a Weinhold hybrid orbital basis it was possible to intercept each hybrid orbital pair's contribution to the total SOC. This led to programming which reveals the locality of spin-orbit-coupling in triplets. The method was applied to some triplet photochemical reactions. For example, in the Type B rearrangement, it was shown that the conversion of the triplet to ground state occurs just as the final three-membered ring is formed. More generally, geminal orbital pairs contribute most to SOC in species such as diradicals, and not from interaction of the separated odd-electron centers.

<239>. "Novel Dissection Analysis of Spin-Orbit Coupling in the Type B Cyclohexenone Photorearrangement. What Controls Photoreactivity. Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Kutateladze, A. G. Journal of Organic Chemistry 1995, 60, 6008–6009.

<242>. "New Approaches to Singlet-Triplet Spin-Orbit Coupling in Photochemistry and Diradical Chemistry; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Kutateladze, A. G. Journal of the American Chemical Society 1996, 118, 249–250.

The Mechanism of The Tri-pi-Methane Rearrangement

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In view of the generality and utility of the Di- Methane Rearrangement, we pursued the search for a Tri-pi-Methane process. This was successful, leading to a five-membered ring photoproduct. The requirement was for at last two vinyl groups attached to the central sp3-hydridized carbon. Interestingly, it was found that the Di- Methane product was simultaneously produced and could rearrange to the five-membered ring. Despite this, evidence was adduced for a direct formation of the Tri--Methane product.

<271>. "Regioselectivity of the Tri--Methane Rearrangement; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Novak, T. Journal of Organic Chemistry 2003, 68, 5056–5066.


The Delta-Density Matrix method of predicting both excited and ground state reactivity

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This involved obtaining a Density Matrix, A. for a reactant (n a hybrid orbital basis), perturbing the reactant by one of – photon absorption, electron introduction to give a radical anion, or electron removal to give a radical cation but with the original geometry of A being retained. The new species, B, with the geometry of A affords a new density matrix, one which now corresponds to a higher energy due to non-ideal geometry. Subtraction of the two matrices gives a Delta Density Matrix, D = B – A. The negative elements correspond to bonds which are weakened. The positive elements correspond to bonds which wish to form. One then has a still more powerful Computational Equivalent of "Electron Pushing". This includes prediction of the primary photochemical step (one of three controlling factors).

<260>. "Energy Distribution and Redistribution and Chemical Reactivity. The Generalized Delta Overlap-Density Method for Ground State and Electron Transfer Reactions; A new Quantitative Counterpart of Electron Pushing", Zimmerman, H. E.; Alabugin, I. V. Journal of the American Chemical Society 2001, 121, 2265–2270.

Barrelene

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There had been speculation about whether [2,2,2]-bicyclooctatriene would be aromatic with its six pi electrons but the compound had not been synthesis. It was the Zimmerman group which obtained the first synthesis and showed that the molecular would be “non-aromatic” from simple one-electron computations possible at the time (1960). This was noted to have a Moebius array of pi-orbitals.

<21>. "Bicyclo[2.2.2]-2,5,7-triene (Barrelene), A Unique Cyclic Six Electron Pi System", Zimmerman, H. E.; Paufler, R. Journal of the American Chemical Society 1960, 82, 1514–1515.

<81>. "Synthesis and Physical Properties of Barrelene, a Unique Möbius-like Molecule", Zimmerman, Grunewald, G. L.; H. E.; Paufler, R. M.; Sherwin, M. A. Journal of the American Chemical Society, 1969, 91, 2330–2338.

Semibullvalene

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The first synthesis of semibullvalene and a number of subsequent syntheses were reported. The first was in 1966. The molecule was demonstrated to have such rapid valence tautomerism in a degenerate Cope rearrangement that even at the lowest temperature available at the time the NMR showed only three signals. The semibullvalene was obtained from the photolysis of barrelene. The molecule was subsequently obtained from several alternative syntheses which were devised.

<60>. "Mechanistic Organic Photochemistry. XXIV. The Mechanism of the Conversion of Barrelene to Semibullvalene. A General Photochemical Process", Zimmerman, Binkley, R. W.; Givens, R. S.; Sherwin, M. A. Journal of the American Chemical Society, 1967, 89, 3932–3933.

<70>. "The Photochemical Conversion of Cyclooctatetraene to Semibullvalene. Mechanistic and Exploratory Photochemistry. XXXVII", Zimmerman, H. E.; Iwamura, H. Journal of the American Chemical Society, 1968, 90, 4763–4764.

<85>. "C8H8 Interconversions. An Unusual Rearrangement Providing a New Route to Semibullvalene", Zimmerman, H. E.; Robbins, J. D.; Schantl, J. Journal of the American Chemical Society, 1969, 91, 5878–5879.

Reversal of the Stereochemistry of Less-Hindered Protonation of Enols and Enolates

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By synthesis of molecules having a pyridyl group strategically placed near the enolic carbon it proved possible to deliver the proton to the more hindered side of the delocalized enolate species.

<251>. "Reversal of The Stereochemistry of Kinetic Protonation by Intramolecular Proton Delivery and a Remarkable Dependence of Selectivity on Donor Concentration", Zimmerman, H. E.; Ignatchenko, A. Journal of the American Chemical Society, 1998, 120, 12992–12993.

<267>. "Inter and Intramolecular Stereoselective Protonation of Enols", Zimmerman, H. E.; Wang, P., Journal of Organic Chemistry 2002, 69, 9216–9226.

Experimental and Theoretical evidence on the role of zwitterions vs diradicals in organic chemistry

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Independent generation of these and comparison with the product selectivity in complex reactions.

<116>. "Generation of Photochemical Intermediates Without Light; the Type B Zwitterion. Mechanistic Organic Photochemistry. LXXI. Zimmerman, H. E.; Epling, G. A. Journal of the American Chemical Society, 1972, 94, 7806–7811.

<181>. "Regioselectivity in Cyclohexadienone Photochemistry; the Role of Zwitterions in Type A Photochemical and Dark Rearrangements. Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Pasteris, R. L. Journal of Organic Chemistry, 1980, 45, 4864–4875.

<182>. "Type A Zwitterions and Cyclohexadienone Photochemical Rearrangements. Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Pasteris, R. J. Journal of Organic Chemistry, 1980, 45, 4876–4891.

The "Type-B" Rearrangement

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The rearrangement of 4-Arylcyclohexenones to bicyclo[3.1.0]hexanones. The first example of this was the photolysis of 4,4-diphenylcyclohexenone to afford 5,6-diphenylbicyclo[3.1.0]hex-3-en-2-one. Since that time the reaction has become common.

<42>. "Mechanistic and Exploratory Organic Photochemistry, IX. Phenyl Migration in the Irradiation of 4.4-Diphenylcyclohexenone", Zimmerman, H. E.; Wilson, J. W. Journal of the American Chemical Society, 1964, 86, 4036–4042.

<58>. "Photochemical Migratory Aptitudes in Cyclohexenones. Mechanistic and Exploratory Organic Photochemistry. XXIII", Zimmerman, H. E.; Rieke, R. D.; Scheffer, J. R. Journal of the American Chemical Society, 1967, 89, 2033–2047.

The alpha,beta-epoxyketone rearrangement

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Affording beta-diketones and mechanism. This rearrangement was uncovered in 1964. The Swiss (Jeger) group reported the reaction simultaneously.

<36>. "A General Theory of Photochemical Reactions. VII. Mechanisms of Epoxy Ketone Reactions", Zimmerman, H. E.; Cowley, B. R.; Tseng, C-Y.; Wilson, J. W. Journal of the American Chemical Society, 1964, 86, 947–948.

<40>. "Photochemical Reactions of 2.3-Epoxy-2-methyl-3-phenylindanone", Zimmerman, Simkin, R. D. Tetrahedron Letters, 1964, 1847–1851.

The rearrangement of bicyclo[3.1.0]hexenones

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Via a six-ring zwitterion to phenolic product [Type B Bicyclic]. The rearrangement of the bicyclic enones with fission of the internal three-ring bond, formation of a zwitterion, and migration of a group to a positive center of the zwitterion – was discovered. This proved to be a very general photochemical reaction.

<51>. "Mechanistic Organic Photochemistry. XVI. The Photochemistry of 6,6-Diphenylbicyclo[3.1.0]hex-3-en-2-one", Zimmerman, H. E.; Nasielski, J.; Keese, R.; Swenton, J. S. Journal of the American Chemical Society, 1966, 88, 4895–4903.

<59>. "Chronology in Photochemical Mechanisms. The Reaction of 6-Phenyl-6-p-cyano phenylbicyclo[3.1.0]hex-3-en-2-one. Mechanistic Organic Photochemistry. XXV, "Zimmerman, H. E.; J. O. Grunewald, J. O. Journal of the American Chemical Society, 1967, 89, 3354–3356.

<246>. "Photochemistry in a Crystalline Cage; Control of Type-B Bicyclic Reaction Course; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Sebek, P. Journal of the American Chemical Society, 1997, 119 3677–3690.

250. "Ab Initio Computations of Reacting Species in Crystal Lattices; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Sebek, P.; Zhu, Z., Journal of the American Chemical Society, 1998, 120, 8549–8550.

Photochemistry without Light

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By use of intramolecular dioxetane functions, the triplet excited state could be generated thermally to give typical photochemical reactivity. The intramolecular generation followed literature examples of intermolecular generation.

<141>. "A Photochemical Rearrangement Without Light. Dioxetane Effected Photochemistry by Direct Intramolecular Excitation", Zimmerman, H. E.; Keck, G. E. Journal of the American Chemical Society, 1975, 97, 3527–3528.

<152>. "Molecular Rearrangements of Excited States Generated by Intramolecular Dioxetane Scission. Photochemistry Without Light. Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Keck, G. E.; Pflederer, J. L. Journal of the American Chemical Society, 1976, 98, 5574–5581.

<204>. "Rapidly Rearranging Excited States of Bichromophoric Molecules; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E. Lynch, D. C. Journal of the American Chemical Society, 1985, 107, 7745–7756.


REFERENCES COMPLETE LIST

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1. "The Structure of Benzilide", H. H. Wasserman, H. H.; Zimmerman, H. E. Journal of the American Chemical Society, 1950, 75, 5787.

2. "The Structure of the Diphenacyl Halides", Wasserman, H. H.;Aubrey, N. E.; Zimmerman, H. E. Journal of the American Chemical Society, 1953, 75, 96–98.

3. "Stereoisomerism of Isopulegol Hydrates and Some Analogous 1,3-Diols", Zimmerman, H. E.; English, Jr., J. Journal of the American Chemical Society, 1953, 76, 2367–2370.

4. "The Cleavage Reaction of 1,3-Diols. I", Zimmerman, H. E.; English, Jr., J. Journal of the American Chemical Society, 1954, 76, 2285–2290.

5. "The Cleavage Reaction of 1,3-Diols. II. The Synthesis, Cleavage and Proof of Configuration of Two Pairs of Diastereomeric Secondary-Tertiary 1,3-Diols", Zimmerman, H. E.; English, Jr., J. Journal of the American Chemical Society,1954, 76, 2291–2294.

6. "The Cleavage Reaction of 1,3-Diols. III. The Synthesis of a Pair of Diastereomeric Ditertiary 1,3-Diols and an Effect of Configuration on Mode of Cleavage", Zimmerman, H. E.; English, Jr., J. Journal of the American Chemical Society,1954, 76, 2294–2300.

7. "The Stereochemistry of the Ketonization Reaction of Enols", Zimmerman, H. E. Journal of Organic Chemistry, 1955, 20, 549–557.

8. "The Stereochemistry of the Ketonization Reaction of Enols. II", Zimmerman, H. E. Journal of the American Chemical Society, 1956, 78, 1168–1173.

9. "The Stereochemistry of the Ketonization Reaction of Enols. III", Zimmerman, H. E.; Giallombardo, H. J. Journal of the American Chemical Society, 1956, 78, 6259–6263.

10. "The Stereochemistry of the Ivanov and Reformatsky Reactions. I", Zimmerman, H. E.; Traxler, M. D. Journal of the American Chemical Society, 1957, 79, 1920–1923.

11. "Carbanion Rearrangements. I", Zimmerman, H. E.; Smentowski, F. J. Journal of the American Chemical Society, 1957, 79, 5455–5457.

12. "The Stereochemistry of Ketonization. IV", Zimmerman, H. E. Journal of the American Chemical Society, 1957, 79, 6554–6558.

13. "The Stereochemistry of Ketonization. V. aci-Nitro Tautomerism", Zimmerman, H. E.; Nevins, T. E. Journal of the American Chemical Society, 1957, 79, 6559–6561.

14. "The Stereochemistry of Ketonization. VI. Decarboxylation of 2-Phenylcyclohexane-1,1-dicarboxylic Acid", Zimmerman, H. E.; Cutshall, T. W. Journal of the American Chemical Society, 1958, 80, 2893–2896.

15. "The Stereochemistry of Proton Transfer Reactions. VII", Zimmerman, H. E.; Thyagarajan, B. S. Journal of the American Chemical Society, 1958, 80, 3060–3064.

16. "Overlap Control of Carbanionoid Reactions. I. Stereoselectivity in Alkaline Epoxidation", Zimmerman, H. E.; Singer, L.; Thyagarajan, B. S. Journal of the American Chemical Society, 1959, 81, 108–116.

17. "Overlap Control of Carbanionoid Reactins. II. Stereochemistry of the Perkin and Related Condensation Reactions", Zimmerman, H. E.; Ahramjian, L. Journal of the American Chemical Society, 1959, 81, 2086–2091.

18. "The Stereochemistry of Ketonization. VIII. Acyclic Enols", Zimmerman, H. E.; Chang, W-H Journal of the American Chemical Society, 1959, 81, 3634–3643.

19. "The Stereochemistry of Ketonization. IX. The 1,9-Enol of 1-Decalone", Zimmerman, H. E.; Mais, A. Journal of the American Chemical Society, 1959, 81, 3644–3651.

20. "The Stereochemistry of Ketonization. X. Enols from Haloacids", Zimmerman, H. E.; Cutshall, T. W. Journal of the American Chemical Society, 1959, 81, 4305–4308.

21. "Bicyclo[2.2.2]-2,5,7-triene (Barrelene), A Unique Cyclic Six Electron Pi System", Zimmerman, H. E.; Paufler, R. Journal of the American Chemical Society 1960, 82, 1514–1515.

22. "The Stereochemistry of Sulfone-Stabilized Carbanions", Zimmerman, H. E.; Thyagarajan, B. S. Journal of the American Chemical Society, 1960, 82, 2505–2511.

23. "Overlap Control of Organic Reactions. III. The Stereochemistry of the Darzens Reaction", Zimmerman, H. E.; Ahramjian, L. Journal of the American Chemical Society, 1960, 82, 5459–5466.

24. "The Mechanism of the Thermal Decomposition of Azines", Zimmerman, H. E.; Somasekhara, S. Journal of the American Chemical Society, 1960, 82, 5865–5873.

25. "Carbanion Rearrangements. II", Zimmerman, H. E.; Zweig, A. Journal of the American Chemical Society, 1961, 83, 1196–1213.

26. "The Photochemical Rearrangement of 4,4-Diphenylcyclohexadienone. Paper I on a General Theory of Photochemical Reactions", Zimmerman, H. E.; Schuster, D. I. Journal of the American Chemical Society, 1961, 83, 4486–4487.

27. "Orientation in Metal Ammonia Reductions", Zimmerman, H. E., Tetrahedron, 1961, 16, 169–176.

28. "A Mechanistic Approach to Organic Photochemistry", Zimmerman, H. E. Seventeenth National Organic Symposium of the American Chemical Society, Abstracts, Bloomington, Indiana, 1961, pp 31–41.

29. "Mechanistic Organic Photochemistry. V. Phenyl Migration in a New Photochemical Reaction", Zimmerman, H. E.; Dürr, H. G.; Lewis, R. G.; Bram, S., Journal of the American Chemical Society, 1962, 84, 4149–4150.

30. "Mechanistic Organic Photochemistry. IV. Photochemical Rearrangements of 4,4-Diphenylcyclohexadienone", Zimmerman, H. E.; Schuster, D. I. Journal of the American Chemical Society, 1962, 84, 4527–4540.

31. "Mechanistic Organic Photochemistry. II. Solvolytic Photochemical Reactions", Zimmerman, H. E.; Sandel, V. R. Journal of the American Chemical Society, 1963, 85, 915–922.

32. "Mechanistic Organic Photochemistry. III. Excited State Solvolyses", Zimmerman, H. E.; Somasekhara, S. Journal of the American Chemical Society, 1963, 85, 922–927.

33. "Mechanistic Organic Photochemistry.", Zimmerman, H. E. Tetrahedron, 1963, Suppl. 2, 19, 393–401.

34. "Base-Catalyzed Rearrangements", Chapter 6 of "Molecular Rearrangements", Zimmerman, H. E., Ed. P. DeMayo, Interscience 345–406, New York, 1963.

35. "A New Approach to Mechanistic Organic Photochemistry", Zimmerman, H. E. in Advances in Photochemistry, Editors: A. Noyes, Jr., G. S. Hammond and J. N. Pitts, Jr., Interscience, Vol. 1, 183–208, 1963.

36. "A General Theory of Photochemical Reactions. VII. Mechanisms of Epoxy Ketone Reactions", Zimmerman, H. E.; Cowley, B. R.; Tseng, C-Y.; Wilson, J. W. Journal of the American Chemical Society, 1964, 86, 947–948.

37. "The Chemistry of Barrelene. II. A Remarkable Transformation to Napthalene Derivatives", Zimmerman, H. E.; Grunewald, G. L. Journal of the American Chemical Society, 1964, 86, 1434–1435.

38. "Mechanistic Organic Photochemistry. VIII. Identification of the n-* Triplet in Rearrangement of 4,4-Diphenylcyclohexadienone, " Zimmerman, H. E.; Swenton, J. S. Journal of the American Chemical Society, 1964, 86, 1436–1437.

39. "A Study of Hindered Divalent Carbon Species and Diazo Compounds", Zimmerman, H. E.; Paskovich, D. H. Journal of the American Chemical Society, 1964, 86, 2149–2160.

40. "Photochemical Reactions of 2.3-Epoxy-2-methyl-3-phenylindanone", Zimmerman, Simkin, R. D. Tetrahedron Letters, 1964, 1847–1851.

41. "The Photochemical Reaction of Benzoquinone With Tolan", Zimmerman, H. E.; Craft, L. Tetrahedron Letters, 1964, 2131–2136.

42. "Mechanistic and Exploratory Organic Photochemistry, IX. Phenyl Migration in the Irradiation of 4.4-Diphenylcyclohexenone", Zimmerman, H. E.; Wilson, J. W. Journal of the American Chemical Society, 1964, 86, 4036–4042.

43. "A Report on Recent Photochemical Investigations", Zimmerman, H. E. Pure and Applied Chemistry, 1964, 9, 493–498.

44. "Mechanistic and Exploratory Photochemistry. XII. Characterization of the Reactivity of the -Carbon in the Triplet Excited State of -Unsaturated Ketones", Zimmerman, H. E.; Hahn, R. C.; Morrison, H.; Wani, M. C. Journal of the American Chemical Society, 1965, 87, 1138–1140.

45. "The Relation of Cyclohexenone to Cyclohexadienone Rearrangements. Mechanistic Organic Photochemistry. XIV", Zimmerman, H. E.; Lewis, R. G.; McCullough, J. J.; Padwa, A.; Staley, S.; Semmelhack, M. Journal of the American Chemical Society, 1966, 88, 159–161.

46. "The Chemistry of Barrelene. III. A Unique Photoisomerization to Semibullvalene", Zimmerman, H. E.; Grunewald, G. L. Journal of the American Chemical Society 1966, 88, 183–184.

47. "On Molecular Orbital Correlation Diagrams, the Occurrence of Möbius Systems in Cyclization Reactions, and Factors Controlling Ground and Excited State Reactions. I", Zimmerman, H. E. Journal of the American Chemical Society, 1966, 88, 1564–1565.

48. "On Molecular Orbital Correlation Diagrams, Möbius Systems, and Factors Controlling Ground and Excited State Reactions. II", Zimmerman, H. E. Journal of the American Chemical Society, 1966, 88, 1566–1567.

49. "Mechanistic and Exploratory Photochemistry, XV. The Relations of Cyclohexenone to Cyclohexadienone Rearrangements", Zimmerman, H. E.; Lewis, R. G.; McCullough, J. J.; Padwa, A.; Staley, S.; Semmelhack, M. Journal of the American Chemical Society, 1966, 88, 1965–1973.

50. "Organic Photochemistry. XVII. Competition Between Phenyl Migration, Type A Skeletal Rearrangement, and New Rearrangement in 4,5-Diphenylcyclohexenone", Zimmerman, H. E.; Sam, D. J. Journal of the American Chemical Society, 1966, 88, 4114–4116.

51. "Mechanistic Organic Photochemistry. XVI. The Photochemistry of 6,6-Diphenylbicyclo[3.1.0]hex-3-en-2-one", Zimmerman, H. E.; Nasielski, J.; Keese, R.; Swenton, J. S. Journal of the American Chemical Society, 1966, 88, 4895–4903.

52. "Mechanistic and Exploratory Organic Photochemistry. XVIII. Competing Pathways in the Rearrangements of 4,5-Diphenylcyclohexenone", H. E. Zimmerman and D. J. Sam, Journal of the American Chemical Society, 1966, 88, 4905–4914.

53. "Interpretation of Some Organic Photochemistry", Zimmerman, H. E. Science, 1966, 153, 837–844.

54. "The Generation of Photochemical Intermediates Without Light. Mechanistic Organic Photochemistry. XX", Zimmerman, H. E.; Döpp, D.; Huyffer, P. S. Journal of the American Chemical Society, 1966, 88, 5352–5353.

55. "Pyrone", Zimmerman, H. E.; Grunewald, G. L.; Paufler, R. M. Organic Syntheses, (E. J. Corey, Editor), 1966, 46, 101–104.

56. "Mechanistic Organic Photochemistry. XXI. Electronic Details of the 2,5-Cyclohexadienone Rearrangement", Zimmerman, H. E.; Swenton, J. S. Journal of the American Chemical Society, 1967, 89, 906–912.

57. "The Photochemistry of Dibenzoylethylenes. Mechanistic and Exploratory Organic Photochemistry. XXII", Zimmerman, H. E.; Givens, R. S.; Lewis, R. G. Journal of the American Chemical Society, 1967, 89, 1863–1874.

58. "Photochemical Migratory Aptitudes in Cyclohexenones. Mechanistic and Exploratory Organic Photochemistry. XXIII", Zimmerman, H. E.; Rieke, R. D.; Scheffer, J. R. Journal of the American Chemical Society, 1967, 89, 2033–2047.

59. "Chronology in Photochemical Mechanisms. The Reaction of 6-Phenyl-6-p-cyano phenylbicyclo[3.1.0]hex-3-en-2-one. Mechanistic Organic Photochemistry. XXV, "Zimmerman, H. E.; J. O. Grunewald, J. O. Journal of the American Chemical Society, 1967, 89, 3354–3356.

60. "Mechanistic Organic Photochemistry. XXIV. The Mechanism of the Conversion of Barrelene to Semibullvalene. A General Photochemical Process", Zimmerman, Binkley, R. W.; Givens, R. S.; Sherwin, M. A. Journal of the American Chemical Society, 1967, 89, 3932–3933.

61. "Pathways Leading From Excited-State Reactant to Ground-State Products in Dienone Photochemistry. Mechanistic and Exploratory Organic Photochemistry. XXVI", Zimmerman, H. E.; Grunewald, J. O. Journal of the American Chemical Society, 1967, 89, 5163–5172.

62. "Methylene Analogs of Cyclohexenones. Mechanistic and Exploratory Organic Photochemistry. XXVIII", Zimmerman, H. E.; Samuelson, G. E. Journal of the American Chemical Society, 1967, 89, 5971–5973.

63. "* Rearrangements. The Photochemistry of 1-Methylene-4,4-Diphenyl-2,5- cyclohexadiene as a Dienone Analog. Mechanistic and Exploratory Organic Photochemistry. XXIX", Zimmerman, H. E.; Hackett, P.; Juers, D. F.; Schröder, B. Journal of the American Chemical Society, 1967 89, 5973–5974.

64. "Organic Photochemistry. XXVII. Electronically Excited State Structures", Zimmerman; H. E.; Binkley; R. W.; McCullough, J. J.; Zimmerman, G. A. Journal of the American Chemical Society, 1967, 89, 6589–6595.

65. "A Sulfone -Elimination Rearrangement and a Related Diazoethane Decomposition", Zimmerman, H. E.; Munch, J. H. Journal of the American Chemical Society, 1967, 90, 187–196.

66. "The Photochemistry of 4,4,5-Triphenyl-2-cyclohexen-1-one. Mechanistic and Exploratory Organic Photochemistry. XXX", Zimmerman, H. E.; Morse, R. L. Morse, Journal of the American Chemical Society, 1968, 90, 954–966.

67. Molecular Details of Photochemical Transformations", Zimmerman, H. E. Photochem. and Photobiol., 1968, 7, 519–523.

68. "Electronic Details of the Photochemical Phenyl Migration in 4,4-Diphenylcyclohexenone. Mechanistic Organic Photochemistry. XXXI", Zimmerman, H. E.; Hancock, K. G. Journal of the American Chemical Society, 1968, 90, 3749–3760.

69. "Control of Photochemical Reactivity by Excited State Multiplicity. Mechanistic and Exploratory Organic Photochemistry. XXXIV", Zimmerman, H. E.; Givens, R. S.; Pagni, R. M. Journal of the American Chemical Society, 1968 90, 4191–4193.

70. "The Photochemical Conversion of Cyclooctatetraene to Semibullvalene. Mechanistic and Exploratory Photochemistry. XXXVII", Zimmerman, H. E.; Iwamura, H. Journal of the American Chemical Society, 1968, 90, 4763–4764.

71. "The Stereochemistry and Mechanism of the Photochemical Interconversion of cis- and trans-5,6-Diphenylbicyclo[3.1.0]hexan-2-ones. Mechanistic Organic Photochemistry. XXXII", Zimmerman, H. E.; Hancock, K. G.; Licke, G., Journal of the American Chemical Society, 1968, 90, 4892–4911.

72. "Photochemistry Without Light and the Stereochemistry of the Type A Dienone Rearrangement. Organic Photochemistry. XXXVI", Zimmerman, H. E.; Crumrine, D. S. Journal of the American Chemical Society, 1968, 90, 5612–5614.

73. "The Stereochemistry of Protonation. XI", Zimmerman, H. E.; Mariano, P. S., Journal of the American Chemical Society, 1968, 90, 6091–6096.

74. "The Photochemistry of Benzobarrelene. Mechanistic and Exploratory Organic Photochemistry. XXXV", Zimmerman, H. E.; Givens, R. S.; Pagni, R. M. Journal of the American Chemical Society, 1968, 90, 6096–6108.

75. "Electronically Excited Species in Organic Photochemistry; a Reply", Zimmerman, H. E. Journal of the Chemical Society, Chemical Communications, 1968 174–176.

76. "Mechanistic Organic Photochemistry", Zimmerman, H. E. Angewandte Chemie, 1969, 81, 45–55. Angewandte Chemie International Edition, 1969, 8, 1–11.

77. "Photochemistry Without Light and the Stereochemistry of the Type A Dienone Rearrangment; Organic Photochemistry. XXXVIII", Zimmerman, H. E.; Crumrine, D. S.; Döpp, D. Huyffer, P. S. Journal of the American Chemical Society, 1969, 91, 434–445.

78. "Relative Rates of Aryl Migrations in Excited State Transformations. Mechanistic and Exploratory Organic Photochemistry. XXXIX", Zimmerman, H. E.; Lewin, N. Journal of the American Chemical Society, 1969, 91, 879–886.

79. "Energy Barriers in Photochemical Molecular Rearrangements. Mechanistic and Exploratory Organic Photochemistry. XL. Zimmerman, H. E.; Elser, W. R.; Journal of the American Chemical Society, 1969, 91, 887–896.

80. "The Di--Methane Rearrangement. Interaction of Electronically Excited Vinyl Chromophores. Zimmerman, H. E.; Mariano, P. S. Journal of the American Chemical Society, 1969, 91, 1718–1727.

81. "Synthesis and Physical Properties of Barrelene, a Unique Möbius-like Molecule", Zimmerman, Grunewald, G. L.; H. E.; Paufler, R. M.; Sherwin, M. A. Journal of the American Chemical Society, 1969, 91, 2330–2338.

82. "The Barrelene to Semibullvalene Transformation. Correlation of Excited State Potential Energy Surfaces With Reactivity. Mechanistic and Exploratory Organic Photochemistry. XLIV", Zimmerman, H. E.; Binkley, R. W.; Givens, R. S.; Sherwin, M. A.; Grunewald, G. L.; Journal of the American Chemical Society, 1969, 91, 3316–3323.

83. "The Di-Methane Rearrangement of 1-Methylene-4,4-Diphenyl-2-cyclohexene and Related Photochemical Processes. Mechanistic and Exploratory Organic Photochemistry. XLV", Zimmerman, H. E.; Samuelson, G. E. Journal of the American Chemical Society, 1969, 91, 5307–5318.

84. "The 2,5-Cyclohexadienone That Could Not Rearrange Photochemically. Mechanistic and Exploratory Organic Photochemistry. XLVI", Zimmerman, H. E.; Jones III, G. Journal of the American Chemical Society, 1969, 91, 5678–5679.

85. "C8H8 Interconversions. An Unusual Rearrangement Providing a New Route to Semibullvalene", Zimmerman, H. E.; Robbins, J. D.; Schantl, J. Journal of the American Chemical Society, 1969, 91, 5878–5879.

86. "Mechanistic and Exploratory Organic Photochemistry. XLIX. Excited State Aromaticity and Energy Localization. The Di-Methane Rearrangement of Naphthobarrelenes", Zimmerman, H. E.; Bender, C. O. Journal of the American Chemical Society, 1969, 91, 7516–7518.

87. "Organic Photochemistry. LIII. Directionality of the Di--Methane Rearrangement and Alkyl Migration in a Unique Singlet Vinylcyclopropane Transformation", Zimmerman, H. E.; Pratt, A. C. Journal of the American Chemical Society, 1970, 92, 1407–1409.

88. "Organic Photochemistry. LIV. Concertedness, Stereochemistry, and Energy Dissipation in the Di-Methane Rearrangement. Source of Singlet-Triplet Reactivity Differences", Zimmerman, H. E.; Pratt, A. C. Journal of the American Chemical Society, 1970, 92, 1409–1411.

89. "Organic Photochemistry. LV. Geometric Control of Multiplicity in the Di--Methane Rearrangement" Zimmerman, H. E.; Epling, G. A. Journal of the American Chemical Society, 1970, 92, 1411–1412.

90. "Excited State Bond Weakening in Photochemical Rearrangements of Cyclopropyl Ketones. Exploratory and Mechanistic Organic Photochemistry. XLVIII", Zimmerman, H. E.; Hixson, S. S.; McBride, E. F. Journal of the American Chemical Society, 1970, 92, 2000–2015.

91. "Thermal and Photochemical Interconversions of Cyclooctatetraenes and Semibullvalenes. Exploratory Organic Photochemistry. LII", Zimmerman, H. E.; Iwamura, H. Journal of the American Chemical Society, 1970, 92, 2015–2022.

92. "Excited State Electron Distribution in Cyclopropyl Ketone Rearrangements. Mechanistic and Exploratory Organic Photochemistry. LI", Zimmerman, H. E.; Moore, C. M. Journal of the American Chemical Society, 1970, 92, 2023–2031.

93. "The Photochemistry of a Cyclohexadienone Structurally Incapable of Rearrangement. Exploratory and Mechanistic Organic Photochemistry. XLVII, Zimmerman, H. E.; Jones III, G. Journal of the American Chemical Society, 1970, 92 2753–2761.

94. "Walk Processes in Photochemical Molecular Rearrangements. A General Photochemical Transformation. Mechanistic and Exploratory Organic Photochemistry. LVIII", Zimmerman, H. E.; J. M. McCall, D. F. Juers,; Schröder, B. Journal of the American Chemical Society, 1970, 92, 3474–3476.

95. "The Di--Methane Rearrangement of Naphthobarrelenes. Mechanistic and Exploratory Organic Photochemistry. L", Zimmerman, H. E.; Bender, C. O. Journal of the American Chemical Society, 1970, 92, 4366–4376.

96. "Unsymmetrical Substitution and the Direction of the Di--Methane Rearrangement; Mechanistic and Exploratory Organic Photochemistry. LVI", Zimmerman, H. E.; Pratt, A. C. Journal of the American Chemical Society, 1970, 92, 6259–6267.

97. "Stereochemical Aspects pf the Di--Methane Rearrangement; Mechanistic and Exploratory Organic Photochemistry. LVII", Zimmerman, H. E.; Pratt, A. C. Journal of the American Chemical Society, 1970, 92, 6267–6271.

98. "Electron Delocalization in Molecules Containing Formally Orthogonal -systems. 2,4,6-2,',4,',6'-Hexa-t-butyldiphenylacetylene and a Study of Its Radical Anion and Dianion", Zimmerman, H. E.; Dodd, J. R. Journal of the American Chemical Society, 1970, 92, 6507–6515.

99. "Singlet-Triplet Differentiation. Mechanistic and Exploratory Organic Photochemistry. LIX", Zimmerman, H. E.; Hull, V. J. Journal of the American Chemical Society, 1970, 92, 6515–6520.

100. "Excited State Three Ring bond Opening in Cyclopropyl Ketones. Mechanistic Organic Photochemistry. LX", Zimmerman, H. E.; Flechtner, T. W. Journal of the American Chemical Society, 1970, 92, 6931–6935.

101. "Vinylcyclopropane Photochemistry. Mechanistic and Exploratory Organic Photochemistry. LXI", Zimmerman, H. E.; Flechtner, T. W. Journal of the American Chemical Society, 1970, 92, 7178–7183.

102. "Electron and Energy Transfer Between Bicyclo[3.1.0]octane Bridgehead Moieties", Zimmerman, H. E.; McKelvey, R. D. Journal of the American Chemical Society, 1971, 93, 3638–3645.

103. "Electron Delocalization as a Controlling Factor in the Di--Methane Rearrangement. Exploratory and Mechanistic Organic Photochemistry. LXII, Zimmerman, H. E.; Baum, A. A. Journal of the American Chemical Society, 1971, 93, 3646–3653.

104. "Competitive Photochemical Pathways in the Di--Methane Rearrangement. Exploratory and Mechanistic Organic Photochemistry. LXIII", Zimmerman, H. E.; Hackett, P.; Juers, D. F.; McCall, J. M.; Schröder, B. Journal of the American Chemical Society, 1971, 93, 3653–3662.

105. "Slither Motion of Divalent Carbon on -Systems in Photochemical Rearrangements. Exploratory and Mechanistic Organic Photochemistry. LXIII", Zimmerman, H. E.; McCall, J. M.; Schröder, B. Journal of the American Chemical Society, 1971, 93, 3662–3674.

106. "The Möbius-Hückel Concept in Organic Chemistry. Application to Organic Molecules and Reactions", Zimmerman, H. E. Accounts of Chemical Research, 1971, 4, 272–280.

107. "Apparatus for Quantitative and Preparative Photolysis: The Wisconsin Black Box", Zimmerman, H. E. Mol. Photochem., 1971, 3, 281–292.

108. "Cycloheptatrienyldiazomethane. Its Synthesis and Behavior. C8H8 Chemistry. X. Correlation Diagrams and Nodal Properties", Zimmerman, H. E.; Sousa, L. R. Journal of the American Chemical Society, 1972, 94, 834–842.

109. "Duality of Mechanisms in Photoracemization of Optically Active Biphenyls. Mechanistic and Exploratory Organic Photochemistry. LXV", Zimmerman, H. E.; Crumrine, D. S. Journal of the American Chemical Society, 1972, 94, 498–506.

110. "Entrance Onto Potential Energy Surfaces of Photochemical Reactions Without Light; The Type B Reaction. Mechanistic Organic Photochemistry. LXV", Zimmerman, H. E.; Epling, G. A. Journal of the American Chemical Society, 1972, 94, 3245–3246.

111. "Dependence of Sigmatropic Mechanisms on Excited State Multiplicity. Mechanistic and Exploratory Organic Photochemistry. LXVII", Zimmerman, H. E.; Epling, G. A. Journal of the American Chemical Society, 1972, 94, 3647–3649.

112. "Contrasting Cyclopentenone and Cyclohexenone Photochemistry", Zimmerman, H. E.; Little, R. D. Journal of the Chemical Society, Chemical Communications, 1972, 698–700.

113. "The Stereochemistry of the Di--Methane Rearrangement; Mechanistic and Exploratory Organic Photochemistry. LXIX", Zimmerman, H. E.; Baeckstrom, P.; Johnson, T.; Kurtz, D. W. Journal of the American Chemical Society, 1972, 94, 5504–5505.

114. "An Unexpected Sigma Plus Pi Rearrangement of a Di--Methane Reactant. Inhibition of the Di--Methane Rearrangement. Mechanistic and Exploratory Organic Photochemistry. LXX", Zimmerman, H. E.; Pincock, J. A. Journal of the American Chemical Society, 1972, 94, 6208–6209.

115. "Review of Photochemistry and Spectroscopy", by J. P. Simons, Zimmerman, H. E. in Journal of the American Chemical Society, 1972, 94, 6876.

116. "Generation of Photochemical Intermediates Without Light; the Type B Zwitterion. Mechanistic Organic Photochemistry. LXXI. Zimmerman, H. E.; Epling, G. A. Journal of the American Chemical Society, 1972, 94, 7806–7811.

117. "Evidence for Requirement of the Second Pi bond in the -Methane Rearrangement and Observation of Excited Singlet 1,4-Phenyl Di- Migration. Mechanistic and Exploratory Organic Photochemistry. LXXII", Zimmerman, H. H.; Little, R. D. Journal of the American Chemical Society, 1972, 94, 8256–8258.

118. "Multiplicity Control of Reaction Pathways. Mechanistic and Exploratory Organic Photochemistry. LXXIII", Zimmerman, H. E.; Epling, G. A. Journal of the American Chemical Society, 1972, 94, 8749–8761.

119. "MO Following. The Molecular Orbital Counterpart of Electron Pushing", Zimmerman, H. E. Accounts of Chemical Research, 1972, 5, 393–401.

120. "Competitive Naphtho vs. Benzo Bridging in the Di--Rearrangement of Benzo-2,3-naphthobarrelene. Exploratory and Mechanistic Organic Photochemistry. LXXIV", Zimmerman, H. E.; Viriot-Villaume, M-L Journal of the American Chemical Society, 1973, 95, 1274–1280.

121. "Review of Orbital Symmetry, A Problem Solving Approach", by R. E. Lehr and A. P. Marchand, Journal of Chemical Education, A110 (1973), Zimmerman, H. E.

122. "Accentuation of Di--Methane Reactivity by Central Carbon Substitution. Mechanistic and Exploratory Organic Photochemistry. LXXV", Zimmerman, H. E.; Boettcher, R. J.; Braig, W. Journal of the American Chemical Society, 1973, 95, 2155–2163.

123. "Sigma Plus Pi Rearrangements of Di--Methane Systems. Central Substitution and Di--Methane Reactivity. Mechanistic and Exploratory Organic Photochemistry, LXXVI", Zimmerman, H. E.; Pincock, J. A. Journal of the American Chemical Society, 1973, 95, 2957–2963.

124. "The Photochemistry of Mono- and Di-acetylenic Systems. Exploratory and Mechanistic Organic Photochemistry. LXXVII", Zimmerman, H. E.; Pincock, J. A. Journal of the American Chemical Society, 1973, 95, 3246–3250.

125. "A Walk Rearrangement of Diazonorcaradiene. Mechanistic and Exploratory Organic Photochemistry. LXXVIII", Zimmerman, H. E.; Eberbach, W. Journal of the American Chemical Society, 1973, 95, 3970–3976.

126. "Photochemistry of Anthrabarrelene. Mechanistic and Exploratory Organic Photochemistry. LXXIX", Zimmerman, H. E.; Amick, D. R. Journal of the American Chemical Society, 1973, 95, 3977–3982.

127. "Photochemical Rearrangement Effected by Triplet Excitation Transmitted Through a High Energy Moiety. Mechanistic and Exploratory Organic Photochemistry. LXXX", Zimmerman, H. E.; Amick, D. R.; Hemetsberger, H. Journal of the American Chemical Society, 1973, 95, 4606–4610.

128. "Superfast Singlet Excited State Di--Methane Rearrangement and Decay Rates; Picosecond Range Measurements by Single Photon Counting and Use of Magic Multipliers. Mechanistic Organic Photochemistry. LXXXI", Zimmerman, H. E.; Werthemann, D. P.; Kamm, K. S. Journal of the American Chemical Society, 1973, 95, 5094–5095.

129. "The Di--Methane and Oxa-di--Methane Rearrangements", Hixson, S. S.; Mariano, P. S.; Zimmerman, H. E. Chemical Reviews, 1973, 73, 531–551.

130. "A Photochemical 1,3-Sigmatropic Vinyl Migration. Mechanistic and Exploratory Organic Photochemistry. LXXXII", Zimmerman, H. E.; Kurtz, D. W; Tolbert, L. M. Journal of the American Chemical Society, 1973, 95, 8210–8212.

131. "Single Photon Counting and Magic Multipliers in Direct Measurement of Singlet Excited State Di--Methane Rearrangement Rates in the Picosecond Range. Mechanistic Organic Photochemistry. LXXXIII", Zimmerman, H. E.; Werthemann, D. P.; Kamm, K. S. Journal of the American Chemical Society, 1974, 96, 439–449.

132. "C-1 Stereochemistry of the Di--Methane Rearrangement. Mechanistic and Exploratory Organic Photochemistry. LXXXIV", Zimmerman, H. E.; Baeckstrom, P.; Johnson, T.; Kurtz, D. W. Journal of the American Chemical Society, 1974, 96, 1459–1465.

133. "Stereochemistry of the Di--Methane Rearrangement at the Methane Carbon. Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Robbins, J. D.; McKelvey, R. D.; Samuel, C. J.; Sousa, L. R. Journal of the American Chemical Society, 1974, 96, 1974–1976.

134. "Stereochemistry as a Probe for Photochemical Reaction Mechanisms", Zimmerman, H. E. Tetrahedron, Van't Hoff – Le Bel Memorial Issue, 1974, 30, 1617–1628.

135. "Photochemical Rearrangement of 4-Aryl-Substituted Cyclopentenones. Low Temperature Photochemistry and Direct Observation of Reaction Intermediates", Zimmerman, H. E.; Little, R. D. Journal of the American Chemical Society, 1974, 96, 4623–4630.

136. "Stereochemistry at the Methane Carbon in the Di--Methane Rearrangement. Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E. Robbins, J. D.; McKelvey, R. D.; Samuel, C. J.; Sousa, L. R. Journal of the American Chemical Society, 1974, 96, 4630–4–4643.

137. "A Novel Photochemical 1,4-Phenyl Migration. The Role of the Second Double Bond in the Di-Methane Rearrangement. Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Little, R. D. Journal of the American Chemical Society, 1974, 96, 5143–5152.

138. "Substituent Effects and the Di-Methane Rearrangement. Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Cotter, B. R. Journal of the American Chemical Society, 1974, 96, 7445–7453.

139. "Molecular Twisting as a Mode of Excited State Decay. Mechanistic Organic Photochemistry", Zimmerman, H. E.; Kamm, K. S. Journal of the American Chemical Society, 1974, 96, 7821–7823.

140. "Sigma-Pi Interaction. A Cyclopropyl--Methane Rearrangement. Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Samuel, C. J. Journal of the American Chemical Society, 1975, 97, 448–449.

141. "A Photochemical Rearrangement Without Light. Dioxetane Effected Photochemistry by Direct Intramolecular Excitation", Zimmerman, H. E.; Keck, G. E. Journal of the American Chemical Society, 1975, 97, 3527–3528.

142. "Mechanisms of Electron Demotion. Direct Measurement of Internal Conversion and Intersystem Crossing Rates. Mechanistic Organic Photochemistry", Zimmerman, H. E.; Kamm, K. S.; Werthemann, D. P. Journal of the American Chemical Society, 1975, 97, 3718–3725.

143. "Multiplicity and Molecular Flexibility in Controlling Molecular Reactivity. Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Albrecht, F. X.; Haire, J. J. Journal of the American Chemical Society, 1975, 97, 3726–3740.

144. "A New Photochemical Rearrangement. A Cyclopropyl--Methane Rearrangement. Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Samuel, C. J. Journal of the American Chemical Society, 1975, 97, 4025–4036.

145. "Quantum Mechanics for Organic Chemists", Zimmerman, H. E. Academic Press, New York, 1975.

146. "Conformation and Di--Methane Reactivity. Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Tolbert, L. M. Journal of the American Chemical Society, 1975, 97, 5497–5507.

147. "Generation of Photochemical Species on Ground, Excited Singlet, and Triplet Hypersurfaces in Barrelene Photochemistry", Zimmerman, H. E.; Boettcher, R. J.; Buehler, N. E.; Keck, G. E. Journal of the American Chemical Society, 1975, 97, 5635–5637.

148. "Capabilities in Single Photon Counting with Reiterative Convolution; A Reply", Zimmerman, H. E.; Cutler, T. P. Journal of the Chemical Society, Chemical Communications, 1975, 598–599.

149. "Di--Methane Rearrangement", Zimmerman, H. E.; Döpp, D. Houben-Weyl, Methods of Organic Chemistry, G. Thieme Verlag, 1975, 413–448.

150. "Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E. Science, 1976, 191, 523–528.

151. Book Review, "Excited States in Organic Chemistry", J. A. Barltrop and J. D. Coyle, New York, 1975, Zimmerman, H. E. in Science, 1976, Vol. 193.

152. "Molecular Rearrangements of Excited States Generated by Intramolecular Dioxetane Scission. Photochemistry Without Light. Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Keck, G. E.; Pflederer, J. L. Journal of the American Chemical Society, 1976, 98, 5574–5581.

153. "Independent Generation of Cyclopropyldicarbinyl Diradical Species of the Di--Methane Rearrangement. Excited Singlet, Triplet and Ground State Hypersurfaces of Barrelene Photochemistry", Zimmerman, H. E.; Boettcher, R. J.; Buehler, N. E.; Keck, G. E.; Steinmetz, M. G. Journal of the American Chemical Society, 1976, 98, 7680–7689.

154. "Photochemical Rearrangements of an Unsaturated Nitro Compound. Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Roberts, L. C.; Arnold, R. Journal of Organic Chemistry, 1977, 42, 621–629.

155. "The Photochemistry of Vinylcyclopropenes; a New and General Cyclopentadiene Synthesis. Exploratory and Mechanistic Organic Photochemistry", Zimmerman, H. E.; Aasen, S. Journal of the American Chemical Society, 1977, 99, 2342–2344.

156. "Recent Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E. Pure and Applied Chemistry, 1977, 49, 389–398.

157. "The Möbius-Hückel Treatment of Organic Systems and Reactions and MO Following as a Technique in Organic Chemistry", Zimmerman, H. E. in Pericyclic Reactions, Vol. 1, Edited by A. Marchand and R. Lehr, New York, Academic Press, 1977.

158. Book Review "Theory and Practice of MO Calculations on Organic Molecules", I. G. Csizmadia, New York, 1976, Zimmerman, H. E. in Journal of the American Chemical Society, 1977, 99, 6470.

159. "MO Description of Allene", Exam Question Exchange, Zimmerman, H. E. in Journal of Chemical Education, 1977, 54, 10.

160. Book Review: "Ultrashort Light Pulses. Picosecond Techniques and Applications", ed. by S. L. Shapiro (Topics in Applied Physics), Vol. 18), New York, 1977. Zimmerman, H. E. in Die Naturwissenschaften, 1977.

161. "An Electronic Actinometer for Quantum Yield Determination", Zimmerman, H. E.; Cutler, T. P.; Fitzgerald, V. R.; Weight, T. J. Molecular Photochemistry, 1977, 8, 379–385. 162. "Stereochemistry in the Di--Methane Rearrangement; Aryl Migration. Exploratory and Mechanistic Organic Photochemistry", Zimmerman, H. E.; Gannett, T. P.; Keck, G. E. Journal of the American Chemical Society, 1978, 100, 323–324.

163. "Unusual Regioselectivity in the Di--Methane Rearrangement. Reaction Inhibition and Control by Electron Donating Substituents. Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Gruenbaum, W. T.; Journal of Organic Chemistry, 1978, 43, 1997–2005.

164. "Vinylcyclopropene Photochemistry; Photochemistry Applied to Organic Synthesis. Exploratory and Mechanistic Organic Photochemistry", Zimmerman, H. E.; Aasen, S. M. Journal of Organic Chemistry, 1978, 43, 1493–1506.

165. "Topology of the Photochemical Bicycle Reaction. Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Cutler, T. P. Journal of the Chemical Society, Chemical Communications, 1978, 232–234.

166. "Differing Substituent Effects on Rates and Regioselectivities in the Di-- Methane Rearrangement. New Photochemical Theory: Excitation Distribution (the P Matrix), Reaction Inhibition by Vertical Excited State Stabilization, Ground State vs. Excited State Control", Zimmerman, H. E.; Gruenbaum, W. T.; Klun, R. T.; Steinmetz, M. G.; Welter, T. R. Journal of the Chemical Society, Chemical Communications, 1978, 228–230.

167. "Control of Regioselectivity and Excited State Singlet Reaction Rates by Substitution in the Di-Methane Rearrangement. Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Welter, T. R. Journal of the American Chemical Society, 1978, 100, 4131–4145.

168. The Aryl-Vinyl Methane Version of the Di--Rearrangement. Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Steinmetz, M.; Kreil, C. L. Journal of the American Chemical Society, 1978, 100, 4146–4162.

169. "The Di--Methane Rearrangement of Systems With Simple Vinyl Moieties. Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Klun, R. T. Tetrahedron, 1978, 43, 1775–1803.

170. "Generality of the Photochemical Bicycle Rearrangement. Exploratory and Mechanistic Organic Photochemistry", Zimmerman, H. E.; Cutler, T. P. Journal of Organic Chemistry, 1978, 43, 3283–3303.

171. "A New Theoretical Approach in Photochemistry. Minimization of Excited State-Ground State Surface Separation by Selected Molecular Deformation. Vibrational Dissipation of Local Contributions to Excitation Energies", Zimmerman, H. E.; Steinmetz, M. G. Journal of the Chemical Society, Chemical Communications, 1978, 231–232.

172. "Molecular Control of Excited State Cross-Conjugated Triene Rearrangements. Exploratory and Mechanistic Organic Photochemistry", Zimmerman, H. E.; Diehl, D. R. Journal of the American Chemical Society, 1979, 101, 1841–1857.

173. "Stereochemistry of the Aryl-Vinyl Version of the Di--Rearrangement", Zimmerman, H. E.; Gannett, T. P.; Keck, G. E. Journal of Organic Chemistry, 1979, 44, 1982–1989.

174. "Mechanistic and Exploratory Organic Photochemistry. Cyclopropene Studies", Zimmerman, H. E.; Hovey, M. C. Journal of Organic Chemistry, 1979, 44, 2331–2345.

175. "Unusual Organic Photochemistry Effected by Cyano and Methoxy Substitution. Exploratory and Mechanistic Organic Photochemistry", Zimmerman, H. E.; Armesto, D.; Amezua, M. G.; Gannett, T. P.; Johnson, R. P. Journal of the American Chemical Society, 1979, 101, 6367–6383.

176. Book Review, "Excited States in Organic Chemistry and Biochemistry", ed. by B. Pullman and N. Goldblum, Dordrecht and Boston, 1977, in Journal of the American Chemical Society, 1979, 101, 5458.

177. "The Bicycle Rearrangement: Relationship to the Di- Rearrangement and Control by Bifunnel Distortion. Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Factor, R. E. Journal of the American Chemical Society, 1980, 102, 3538–3548.

178. "A Practical Synthesis of Semibullvalene", Turro, N. J.; Liu, J.; Zimmerman, H. E.; Factor, R. E. Journal of Organic Chemistry, 1980, 45, 3511–3512.

179. "The Di-Methane (Zimmerman) Rearrangement", Zimmerman, H. E. in Rearrangements in Ground and Excited States, Vol. 3, Edited by P. DeMayo, Academic Press, New York, 1980.

180. "Rod-like Organic Molecules; Energy Transfer Studies Using Single Photon Counting", Zimmerman, H. E.; Goldman, T. D.; Hirzel, T. K.; Schmidt, S. P. Journal of Organic Chemistry, 1980, 45, 3933–3951.

181. "Regioselectivity in Cyclohexadienone Photochemistry; the Role of Zwitterions in Type A Photochemical and Dark Rearrangements. Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Pasteris, R. L. Journal of Organic Chemistry, 1980, 45, 4864–4875. 182. "Type A Zwitterions and Cyclohexadienone Photochemical Rearrangements. Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Pasteris, R. J. Journal of Organic Chemistry, 1980, 45, 4876–4891.

183. "Di--Methane Hypersurfaces and Reactivity; Multiplicity and Regioselectivity; Relationship -Methane and Bicycle Rearrangements,(Between the Di-" Zimmerman, H. E.; Factor, R. E. Tetrahedron, 1981, 37, Supplement 1, 125–141.

184. "An Unusual Reaction of Terramycycin With Methyl Iodide", Woodward, R. B.; Zimmerman, H. E. Tetrahedron, 1981 37, 311–314.

185. "New Reactions and Theory in Organic Photochemistry: The 1,3-Vinyl Migration and its Relevance to Exchange Integral Control", Zimmerman, H. E; Penn, J. H.; Johnson, M. R. Proceedings of the National Academy of Sciences of the United States of America, 1981, 78, 2021–2025.

186. "Book Review of Principles of Photochemistry, by J. A. Barltrop and J. D. Coyle, Journal of Chemical Education, 1981, A206-A207.

187. "Reactivity of Low Energy Excited States", Zimmerman, H. E.; Blinn, J. R. Tetrahedron, 1981, 19, 3237–3243.

188. "Topics in Photochemistry", Zimmerman, H. E. Topics in Current Chemistry, 1982, 100, 45–73, Springer-Verlag, Heidelberg-New York.

189. "Evaluation of Single Photon Counting Measurements of Excited State Lifetimes", Zimmerman, H. E.; Penn, J. H.; Carpenter, C. W. Proceedings of the National Academy of Sciences of the United States of America, 1982, 79, 2128–2132.

190. "Möbius and Hückel Systems in the SCF and CI Approximations", Zimmerman, H. E. Tetrahedron, 1982, 38, 753–758.

191. "Photochemical Studies of Cyclopropenes and Cyclopentadienes; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Kreil, D. J. Journal of Organic Chemistry, 1982, 37, 2060–2075.

192. "Cyclopropene Photochemistry. Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Bunce, R. A. Journal of Organic Chemistry, 1982, 47, 3377–3396.

193. "Some Theoretical Aspects of Organic Photochemistry", Zimmerman, H. E. Accounts of Chemical Research, 1982, 10, 312–317.

194. "The Bicycle Rearrangement. A Review", Zimmerman, H. E. Chimia, 1982, 36, 423–428.

195. "Vinylcyclopropene Triplet Rearrangement Mechanisms; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Fleming, S. A. Journal of the American Chemical Society, 1983, 105, 622–624.

196. "The Photochemistry of Phenanthrene-substituted Molecules", Zimmerman, H. E.; Wu, G-S. Canadian Journal of Chemistry, 1983, 61, 866–871.

197. "Reactivity of Aryl Vinyl Di--Methane Systems; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Swafford, R. L. Journal of Organic Chemistry, 1984, 48, 3069–3083.

198. "Some Photochemical Rearrangements of Vinylcyclopentadienes; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Ramsden, W. D. Canadian Journal of Chemistry, 1984, 62, 2592–2611.

199. "Dynamic Isotope Dilution as a General Method for Ascertaining Partition of Photochemical Pathways Potentially Utilizing Non-Discernable Intermediates; Application to a New Reaction", Zimmerman, H. E.; Carpenter; C. W.; Weber, A. M. Journal of the American Chemical Society, 1985, 107, 1073–1075.

200. "Enhanced Endo-Exo Selectivity Selectivity in the Stereochemistry of Ketonization of Enols", Zimmerman, H. E.; Linder, L. W. Journal of Organic Chemistry, 1985, 48, 1637–1646.

201. "Diradical Pathways in Vinylcyclopropene Triplet Rearrangements; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Fleming, S. Journal of Organic Chemistry, 1985, 50, 2539–2551.

202. "The Photochemistry of a Biphenylyl Substituted Cyclohexenone; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; King, R. K.; Xu, J-H; Caufield, C. E. Journal of the American Chemical Society, 1985, 107, 7724–7732.

203. "Photochemical Rearrangements of Naphthyl-substituted Enones; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Caufield, C. E.; King, R. K. Journal of the American Chemical Society, 1985, 107, 7732–7744.

204. "Rapidly Rearranging Excited States of Bichromophoric Molecules; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E. Lynch, D. C. Journal of the American Chemical Society, 1985, 107, 7745–7756.

205. "An Unusual Photochemical Rearrangement; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Binkley, R. W. Tetrahedron Letters, 5859–5862, 1985.

206. "Di--Methane Rearrangement of Highly Sterically Congested Molecules; Inhibition of Free Rotor Energy Dissipation. Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Schissel, D. N. Journal of Organic Chemistry, 1986, 51, 196–207.

207. "A Photochemical Reaction Leading from Cyclohexenones to Cyclobutanones; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Solomon, R. D. Journal of the American Chemical Society, 1986, 108, 6276–6289.

208. "A Graph Theoretical Approach to Möbius Systems in Organic Chemistry", Randic, M.; Zimmerman, H. E. "International Journal of Quantum Chemistry", Symposium No. 20, 1986, 185–201.

209. "A Photochemical Long Range Pinacol Rearrangement; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Nuss, John M. Journal of Organic Chemistry, 1986, 51, 4604–4617.

210. "Kinetic Protonation of Enols, Enolates and Analogs; The Stereochemistry of Ketonization", Zimmerman, H. E. Accounts of Chemical Research, 1987, 20, 263–268.

211. "Diradical Rearrangements; An Unusual 1,2-Shift in a Photochemically Generated 1,3-Diradical; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Kamath, A. P. Journal of the American Chemical Society, 1988, 110, 900–911.

212. "The Aryl -Methane Rearrangement; Partitioning of aVersion of the Cyclopropyl- 1,4-Diradical; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Carpenter, C. W. Journal of Organic Chemistry, 1988, 53, 3298–3305.

213. "Cyclopropanols and the Di-Methane Rearrangement; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Nuss, J. M.; Tantillo, A. W. Journal of Organic Chemistry, 1988, 53, 3792–3803.

214. "Photochemical Rearrangements of Molecules Having Quenchers on a Chain; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Weber, A. M. Journal of the American Chemical Society, 1989, 111, 995–1007.

215. "An Assortment of Highly Unusual Rearrangements in the Photochemistry of Vinylcyclopropanes; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Oaks, F. L.; Campos, P. Journal of the American Chemical Society, 1989, 111, 1007–1018.

216. "Electronic and Steric Control of Alpha- Versus Beta-Naphthyl Migratory Aptitudes in Enone Photochemistry; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; St. Clair, J. D. Journal of Organic Chemistry, 1989, 54, 2125–2137.

217. "Confinement Control in Solid State Photochemistry; Photochemistry in a Box", Zimmerman, H. E.; Zuraw, M. J., Journal of the American Chemical Society, 1989, 111, 2358–2361.

218. "Unusual Rearrangements in Di--Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Cassel, J. M. Journal of Organic Chemistry, 1989, 54, 3800–3816.

219. "Photochemistry in a Box; Photochemical Reactions of Molecules Entrapped in Crystal Lattices; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Zuraw, M. J., Journal of the American Chemical Society, 1989, 111, 7974–7989.

220. "The Photochemistry of Some Extended -Systems: Type A and Aryl Migrations of Systems with Extended Conjugation Related to Cyclohexadienones and Cyclohexenones. Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Lamers, P. H., Journal of Organic Chemistry, 1989, 54, 5788–5804.

221. "The Regioselectivity of the Birch Reduction", Zimmerman, H. E.; Wang, P. A., Journal of the American Chemical Society, 1990, 112, 1280–1281. (A Communication).

222. "Rearrangement of 1,3-Diradicals; Arylcyclopropane Photochemistry", Zimmerman, H. E.; Heydinger, J. A. Journal of Organic Chemistry, 1991, 56, 1747–1758.

223. "The Di--Methane Rearrangement", Zimmerman, H. E. Organic Photochemistry 11, 1991 1–36, Marcel Dekker, Inc., New York, Ed. A. Padwa.

224. "A New Photochemical Reaction and Its Mechanism: Rearrangement of Acyl and Imino Cyclopropenes", Zimmerman, H. E.; Wright, C. W. Journal of the American Chemical Society, 1992, 114 363–365.

225. "Novel Rearrangements of Acyl and Imino Cyclopropenes; Multiplicity Dependence and Mechanism", Zimmerman, H. E.; Wright, C. W. Journal of the American Chemical Society, 1992, 114, 6603–6613.

226. "Molecular Rods; Synthesis and Properties", Zimmerman, H. E.; King, R. K.; Meinhardt, M. B. Journal of Organic Chemistry, 1992, 57, 5484–5492.

227. "The Photochemistry of Some Allenic Counterparts of Cyclohexenones and 2,5-Cyclohexadienones", Zimmerman, H. E.; Baker, M. R.; Bottner, R. C.; Morrisey, M. M.; Murphy, S. Journal of the American Chemical Society, 1992, 114, 459–466.

228. "Regioselectivity of the Birch Reduction", Zimmerman, H. E.; Wang, P. A., Journal of the American Chemical Society, 1993, 115, 2205–2216.

229. "Experimental and Theoretical Exploration of the Detailed Mechanism of the Rearrangment of Barrelenes to Semibullvalenes; Diradical Intermediates and Transition States", Zimmerman, H. E.; Sulzbach, H. M.; Tollefson, M. B. Journal of the American Chemical Society, 1993, 115, 6548–6556.

230. "Use of Hückel Methodology With Ab Initio Molecular Orbitals; Polarizabilities and Prediction of Organic Reactions", Zimmerman, H. E.; Weinhold, F. Journal of the American Chemical Society, 1994, 116 1579–1580.

231. "The Photochemistry of Organic Molecules Entwined in Spiderwebs; the Use of PolyMethyl Methacrylate Glass for Restricting Excited State Motion", Zimmerman, H. E.; O'Brien, M. E. Journal of Organic Chemistry, 1994, 59 1809–1816.

232. "A General Predictor for Photoreactivity in Crystal Lattices: Molecular Mechanics in Crystalline Media and Lock and Key Control; Reaction Examples" Zimmerman, H. E.; Zhu, Z., Journal of the American Chemical Society, 1994, 116 9757–9758.

233. "Excited State Reactivity as a Function of Diradical Structure; Evidence for Two Triplet Cyclopropyldicarbinyl Diradical Intermediates With Differing Reactivity", Zimmerman, H. E.; Kutateladze, A. G.; Maekawa, Y.; Mangette J. E. Journal of the American Chemical Society, 1994, 116, 9795–9796.

234. "Contributions to Photochemical Key Steps in Organic Synthesis", Zimmerman, H. E., Verlag Chemie, Weinheim, 1994, Editors J. Mattay and A. G. Griesbeck.

235. "An Overview of Phenomena and Generalizations Introduced by the Zimmerman Group", Zimmerman, H. E. The Spectrum, 7 (3) 1994, Center for Photochemical Sciences, Bowling Green, Ohio.

236. "Singlet Photochemistry of Vinyl Cyclopropenes; Regioselectivity and Mechanism; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Wilson, D. W. Journal of Organic Chemistry, 1995, 60 692–697.

237. "General Theoretical Treatments of Solid-State Photochemical Rearrangements; And, A Variety of Contrasting Crystal Versus Solution Photochemistry", Zimmerman, H. E.; Zhu, Z., Journal of the American Chemical Society 1995, 117, 5245–5262.

238. "The Meta Effect in Organic Photochemistry; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E., Journal of the American Chemical Society 1995, 117, 8988–8991.

239. "Novel Dissection Analysis of Spin-Orbit Coupling in the Type B Cyclohexenone Photorearrangement. What Controls Photoreactivity. Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Kutateladze, A. G. Journal of Organic Chemistry 1995, 60, 6008–6009.

240. "The p-Cyclopropene Rearrangement", Zimmerman, H. E. in Handbook of Photochemistry and Photobiology, Editor William Horspool, CRC Press, London, 1995, Chap 8, pp 115–122; Chap 14, pp 184–193.

241. "The Di-Methane Rearrangement", Zimmerman, H. E. in Handbook of Photochemistry and Photobiology, Editor William Horspool, CRC Press, London, 1995.

242. "New Approaches to Singlet-Triplet Spin-Orbit Coupling in Photochemistry and Diradical Chemistry; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Kutateladze, A. G. Journal of the American Chemical Society 1996, 118, 249–250.

243. "Cyclopropane Photochemistry" Zimmerman, H. E.; in The Chemistry of the Cyclopropyl Group, Wiley & Sons, Ltd., Ed. Zvi Rappoport, Chapter 6, London, 1996.

244. "Novel Radical Cation Reactions of Bichromophoric Systems; Transannular Aryl Migrations; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Hoffacker, K. D. Journal of Organic Chemistry 1996, 61, 6526–6534.

245. "Synthetic Aspects of the Di-Methane Rearrangement", Zimmerman, H. E.; Armesto, D. Chemical Reviews, 1996, 96, 3065–3112.

246. "Photochemistry in a Crystalline Cage; Control of Type-B Bicyclic Reaction Course; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Sebek, P. Journal of the American Chemical Society, 1997, 119 3677–3690.

247. "An Overview of Phenomena and Generalizations Introduced by the Zimmerman Group", Zimmerman, H. E. IAPS Bulletin, 1997, 20, May Issue (1), 74–98.

248. "Some Theoretical Applications to Organic Chemistry", in Modern Electronic Structure Theory and Applications in Organic Chemistry, Zimmerman, H. E., World Scientific Publishing Co., Ed. E. Davidson. 1998.

249. "The Ortho-Meta Effect in Organic Photochemistry; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E., Journal of Physical Chemistry, 1998, 102 5616–5621.

250. "Ab Initio Computations of Reacting Species in Crystal Lattices; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Sebek, P.; Zhu, Z., Journal of the American Chemical Society, 1998, 120, 8549–8550.

251. "Reversal of The Stereochemistry of Kinetic Protonation by Intramolecular Proton Delivery and a Remarkable Dependence of Selectivity on Donor Concentration", Zimmerman, H. E.; Ignatchenko, A. Journal of the American Chemical Society, 1998, 120, 12992–12993.

252. "Control of the Stereochemistry of Kinetic Protonation; Intramolecular Proton Delivery", Zimmerman, H. E.; Ignatchenko, Journal of Organic Chemistry, 1999, 64, 6635–6645.

253. "Dramatic Effects of Crystal Morphology on Solid State Reaction Course; Control by Crystal Disorder; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Alabugin, I. V.; Chen, W., Zhu, Z., Journal of the American Chemical Society, 1999, 121, 11930–11931.

254. "Excited State Energy Distribution and Redistribution and Chemical Reactivity; Mechanistic and Exploratory Organic Photochemistry, Zimmerman, H. E.; Alabugin, I. V. Journal of the American Chemical Society, 2000, 122, 952–953.

255. "Crystal Lattice Photochemistry Often Proceeds in Discrete Stages; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Nesterov, E. E. Organic Letters, 2000, 2, 1169–1171.

256. "The Tri-Methane Rearrangement; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Cirkva, V. Organic Letters, 2000, 2, 2365–2367

257. "Experimental and Theoretical Host-Guest Photochemistry; Control of Reactivity with Host Variation and Theoretical Treatment With a Stress Shaped Reaction Cavity; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Alabugin, I. V.; Smolenskaya, V. N, Tetrahedron, Symposium-in-Print, 2000, 6821–6831.

258. "Rod-like Molecules and Singlet Energy Transfer", Zimmerman, H. E.; Lapin, L. A.; Nesterov, E. E.; Sereda, G. A. Journal of Organic Chemistry, 2000, 65, 7740–7746.

259. "A Ground State TriMethane Rearrangement", Zimmerman, H. E.; Cirkva, V.; Jiang, L. Tetrahedron Letters, 2000, 41, 9595–9597.

260. "Energy Distribution and Redistribution and Chemical Reactivity. The Generalized Delta Overlap-Density Method for Ground State and Electron Transfer Reactions; A new Quantitative Counterpart of Electron Pushing", Zimmerman, H. E.; Alabugin, I. V. Journal of the American Chemical Society 2001, 121, 2265–2270.

261. "The Tri-Methane Rearrangement; Excited and Ground State Versions; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Cirkva, V. Journal of Organic Chemistry 2001, 66, 1839–1851.

262. "An Unusual Rearrangement and its Dependence on Stereochemistry", Zimmerman, H. E.; Wang, P., Helvetica Chimica Acta, 2001, 84, 1342–1346.

263. "Development of Experimental and Theoretical Crystal Lattice Organic Photochemistry; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Nesterov, E. E., Accounts of Chemical Research, 2002, 20, 77–85.

264. "Quantitative Cavities and Reactivity in Stages of Crystal Lattices; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Nesterov, E. E. Journal of the American Chemical Society 2002, 124, 2818–2830.

265. "The Diverted Di-pi-Methane Rearrangement; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Chen, W-C, Org. Letters, 2002, 4, 1155–1158.

266. "Intramolecular Proton Transfer", Zimmerman, H. E.; Wang, P., Organic Letters, 2002, 4, 2593–2595.

267. "Inter and Intramolecular Stereoselective Protonation of Enols", Zimmerman, H. E.; Wang, P., Journal of Organic Chemistry 2002, 69, 9216–9226.

268. "Crystal Lattice Effects on the Photochemistry of 6-Substituted Cyclohexenones", Zimmerman, H. E.; Sereda, G. A. Journal of Organic Chemistry 2003, 68, 283–292.

269. "An Unusual Abnormal Wolff Rearrangement", Zimmerman, H. E.; Wang, P., Canadian Journal of Chemistry 2003, 81, 517–524.

270. "An Experimental and Theoretical Study of the Type C Enone Rearrangement; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Nesterov, E. E. Journal of the American Chemical Society 2003, 124, 5422–5430.

271. "Regioselectivity of the Tri--Methane Rearrangement; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Novak, T. Journal of Organic Chemistry 2003, 68, 5056–5066.

272. "The Effect in the Stereochemistry of Kinetic Ketonization of Enols", Zimmerman, H. E.; Wang, P. J. Journal of Organic Chemistry 2003, 68, 9226–9232.

273. "The Quantitative Cavity Concept in Crystal Lattice Organic Photochemistry; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E., in CRC Handbook of Photochemistry and Photobiology, Ed. Horspool, W., Chap. 75, CRC Inc., 2004.

274. "A Theoretical Approach to Solid State Organic Photochemistry; Mechanistic and Exploratory Organic Photochemistry", Howard E. Zimmerman, in Computational Photochemistry, Ed. A. Kutateladze, Chapter 1, pp 1–40, CRC (Taylor & Francis), New York, 2005. Vol 13 in Molecular and Supramolecular Photochemistry

275. "Some Theoretical Applications to Organic Photochemistry; Excited State and Open Shell Examples", Howard E. Zimmerman, Chapter VIII in Computational Photochemistry, Zimmerman, H. E., Ed. A. Kutateladze, pp 477–510, Marcel-Dekker, New York, 2005.

276. "Development of Theory with Computation", Howard E. Zimmerman, in Computational Photochemistry, Part of a Series titled Theoretical Computational Chemistry, Chap 8, pp 255–278, Ed. M. Olivucci, Elsevier, London, 2005.

277. "The Synthesis of a Highly Reactive Heterocyclic Reactant and its Unusual Photochemistry; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Pushechnikov. A., Organic Letters, 2004, 6, 3779–3780.

278. "Control of Proton Transfer – Intramolecular vs Intermolecular" Zimmerman, H. E.; Cheng, J., Organic Letters, 2005, 7, 2595–2597.

279. "Control of Stereoselective Protonation of Enols", Zimmerman, H. E.; Cheng, J., Journal of Organic Chemistry, 2006, 71, 873–882.

280. "The Stereochemistry of Allenic Enol Tautomerism; Independent Generation and Reactivity" Zimmerman, H. E.; Pushechnikov, A., European Journal of Organic Chemistry, 2006, 15 3491–3497.

281. "Conical Intersection Control of Heterocyclic Photochemical Bond Scission", Zimmerman, H. E.; Mitkin, O., Journal of the American Chemical Society, 2006, 7, 128(39), 12743–12749.

282. "Five Decades of Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E., Pure and Applied Chemistry, 2006, 2193–2203. Porter Award Address.

283. "The Aza-Type B Photochemical Rearrangement; the Role of a Second Carbonyl in Heterocyclic Photochemistry. Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Mitkin, O. D., Journal of Organic Chemistry, 2007, 72, 6091–6096.

284. "Organic Photochemical Rearrangements of Triplets and Zwitterions; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E.; Suryanarayan, European Journal of Organic Chemistry, 2007, 72, 4091–4102.

285. "Triplet Photochemistry of Vinyl Cyclopropenes; Mechanistic and Exploratory Organic Photochemistry", Zimmerman, H. E., Journal of Organic Chemistry 2008, 73, 1247–1251.

286. "An Unusual Reaction of a Substituted Naphthol", Guzei, I. A.; Zimmerman, H. E.; Shorunov, S.; L. C., Journal of Chemical Crystallography 2009, 39 399–406.

287. "Heterocyclic Photochemistry in Contrast with Carbon Behavior; Regioselective Photochemical Rearrangement of an Azacyclohexadienone; Mechanistic and Exploratory Organic Photochemistry Zimmerman", H. E.; Shorunov, S., Journal of Organic Chemistry, 2009, 74, 5411–5416.

Howard E. Zimmerman 20:26, 21 March 2010 (UTC)