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1,3-Dithiolane

From Wikipedia, the free encyclopedia
1,3-Dithiolane
Names
IUPAC name
1,3-Dithiolane
Identifiers
3D model (JSmol)
102455
ChEBI
ChemSpider
82036
UNII
  • InChI=1S/C3H6S2/c1-2-4-5-3-1/h1-3H2 checkY
    Key: MUZIZEZCKKMZRT-UHFFFAOYSA-N checkY
  • C1CSCS1
Properties
C3H6S2
Molar mass 106.20 g·mol−1
Related compounds
Related compounds
Ethane-1,2-dithiol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

1,3-Dithiolane is the organosulfur compound with the formula CH2S2C2H4. Also classified as a heterocycle related cyclopentane by replacing two methylene bridges (-CH
2
- units) with thioether groups. It is an isomer of 1,2-dithiolane.[1] 1,3-Dithiolanes are compounds where one or more H atoms of the parent 1,3-dithiolane are replaced by other groups. These species are more widely studied.

Synthesis

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A common family of 1,3-dithiolanes have the formula RCHS2C2H4. They are obtained by treating an aldehyde with 1,2-ethanedithiol.[2] Related compounds with the formula R2CS2C2H4 are obtained by condensation of 1,2-ethanedithiol with ketones.[3] The dithiolane protected aldehydes and ketones are amenable to many reactions without perturbing the dithiolane ring.[4]

Protecting a carbonyl group by converting it to a 1,3-dithiolane, using 1,2-ethanedithiol
Protecting a carbonyl group by converting it to a 1,3-dithiolane, using 1,2-ethanedithiol

Dithiolanes can often be reverted, i.e., deprotected,[5] to the parent aldehyde and ketone. A variety of reagents have been developed for that purpose.[6]

Reactions

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1,3-Dithiolanes derived from aldehydes can be deprotonated:

RCHS2C2H4 + BuLi → RCLiS2C2H4 + BuH

These organolithium compounds degrade with loss of ethylene to give the dthiocarboxylate:

RCLiS2C2H4 → RCS2Li + C2H4

In contrast, 2-lithio-1,3-dithianes (RCLiS2C3H6) are long-lived.

1,3-Dithiolanes are susceptible to a variety of degradation processes involving organometallic reagents leading to other organosulfur compounds.[2][3]

References

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  1. ^ Teuber, Lene (1990). "Naturally Occurring 1,2-Dithiolanes and 1,2,3-Trithianes. Chemical and Biological Properties". Sulfur Reports. 9 (4): 257–333. doi:10.1080/01961779008048732.
  2. ^ a b Ni, Zhi-Jie; Luh, Tien-Yau (1992). "Nickel-Catalyzed Silylolefination of Allylic Dithioacetals: (E,E)-Trimethyl(4-Phenyl-1,3-Butadienyl)Silane". Organic Syntheses. 70: 240. doi:10.15227/orgsyn.070.0240.
  3. ^ a b Wilson, S. R.; Georgiadis, G. M. (1983). "Mercaptans from Thioketals: Cyclododecyl Mercaptan". Organic Syntheses. 61: 74. doi:10.15227/orgsyn.061.0074.
  4. ^ Dahnke, Karl R.; Paquette, Leo A. (1993). "2-Methylene-1,3-Dithiolane". Organic Syntheses. 71: 175. doi:10.15227/orgsyn.071.0175.
  5. ^ Wuts, P. G. M.; Greene, T. W. (2006). Greene's Protective Groups in Organic Synthesis. NY: J. Wiley. doi:10.1002/0470053488. ISBN 9780470053485. S2CID 83393227.
  6. ^ Banerjee, Ajoy K.; Laya, M. S. (2000). "Reagents for the preparation and cleavage of 1,3-dithiolanes". Russian Chemical Reviews. 69 (11): 947–955. Bibcode:2000RuCRv..69..947B. doi:10.1070/rc2000v069n11abeh000583. S2CID 250918297.
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