Talk:Hexamethylbenzene

Expansion

@DMacks: Thanks for the updates / polishing of my additions. I still have some more to add (I hadn't done the pyramidal dication) but it's good to be collaborating. I am going to change the ruthenium image back to 350px, the caption looks terrible at the smaller size, that's why I increased it. I'm also planning to nominate this for DYK as a x5 expansion, using the dication rearrangement as the hook. Would you like a joint credit? There are images I would like to add but I don't have drawing tools available, would you be able to make them for me? Re the "no commercial use" comment, that was in the article since its first draft so I left it alone. Also, well done on finding the reference to the Le Bel and Greene paper, I looked for it without success. Regards, EdChem (talk) 00:35, 10 January 2017 (UTC)

You're welcome! I have an interest in the dication as a teaching example and because it was in some semi-lay news wires. Let me know what other images you'd like of this or other compounds:) Collaboration is fun! If it weren't for that derivative, I wouldn't have spent time on this article, and that component took a lot of work to get pretty and not-to-technically written, so if that's part of the hook, I wouldn't mind some DYK credit. DMacks (talk) 01:43, 10 January 2017 (UTC)

@EdChem: I don't know the DYK process. How do we go about submitting this thing? DMacks (talk) 11:25, 17 January 2017 (UTC)

@DMacks: The deadline for submitting this is in just over 12 hours time, and I will make sure it goes in before then. I have already nominated the trifluoroperacetic acid article, as I think you are aware, and am just doing a few last minute tweaks there. I'm wondering if the hexamethylbenzene article might be eligible for the picture slot. Do you want me to explain how DYK works, or just go ahead and explain on a later one (planning to expand the He-3 NMR one soon)? EdChem (talk) 11:36, 17 January 2017 (UTC)

Thanks, yes, I saw the TFPAA nomination (and my most recent set of edits was prompted by comments there). DYK-process explanation can wait for a less time-crunch vehicle. DMacks (talk) 11:45, 17 January 2017 (UTC)

FYI, I had already planned to add info from the e-EROS for exactly the same reason, so it's good to see we were thinking very similarly.  :) EdChem (talk) 12:02, 17 January 2017 (UTC)

The article also prompted me to start trifluoroperacetic acid, something I'd bookmarked to do a while ago and then forgot. DMacks (talk) 03:18, 10 January 2017 (UTC)

@DMacks: Thanks for the modified Ru image, highlighting the pi donors is a good idea. Would you mind if I adjust it back to 350px? The caption looks terrible at the standard size, IMO, because of where the line breaks end up. Also, I've added a cyclotrimerisation image / catalytic cycle, which I'd also like to add to aromatization. I missed the arrow heads in the cycle, but hopefully you can generate a replacement for me.  :) I want to add another image to the preparation section, and still need to work on the Ru and pyramidal bits. EdChem (talk) 23:18, 10 January 2017 (UTC)

That seemed like too much detail (there's nothing unique about this mechanism, reactants, or products, for this reaction-type), and we have a whole article about it that includes the mechanistic details. So I reduced the coverage here to only the specific details for this case, and included an image of the overall reaction. DMacks (talk) 04:09, 12 January 2017 (UTC)

I've turned the Ru image back to 300px now that it works with the caption. I accept the overall image for the cyclotrimerisation, though I would still appreciate a proper SVG image of the catalytic cycle (not for this article). I've added the phenol to hexamethylbenzene image, which would be great if made SVG with the methyls as CH₃ or omitted, and the methanol update too. I added a CN tag to the production of mellitic acid from mellite. I've seen plenty of descriptions of reacting with ammonium carbonate, precipitating with lead, adding hydrogen sulfide, etc, but everywhere I have either references WebElements (and I don't find support for it there) or is copying Wikipedia, so I can't find an actual source. EdChem (talk) 13:26, 12 January 2017 (UTC) It might be from doi:10.1021/ja01280a052. EdChem (talk) 13:51, 12 January 2017 (UTC)

I couldn't find it in that ref, but I did add a different ref that seems authoritative (Justus von Liebig seems like he would know what he's talking about, given that it's a lecture of his at a university that was later named after him). DMacks (talk) 14:37, 12 January 2017 (UTC)

How many of the 2385 sources are we going to reference?

Hey guys, what ever happened to good ole WP:NOTJOURNAL? Several of the 38 references are to a fairly specialized literature. According to ChemAbs, there are >2300 more patents, journals and reports out there. Just sayin'.--Smokefoot (talk) 21:27, 11 January 2017 (UTC)

I removed some of the more-technical details as off-topic, not too-specialized, though perhaps that is just another aspect of too-specialized. That is, I consider this a summary-style article for several underlying more-specilized articles that could reasonably have appropriately specialized refs. Could you let us know an example or two of what is currently too-specialized in your view, as a guide to where to draw the line? DMacks (talk) 04:26, 12 January 2017 (UTC)

Well my attention was caught by the remark about the existence of Mo(CO)₃(HMB), but the mission here is probably not to list a all HMB complexes. Rather what I was getting at is more general: when editors tackle an article chemical compound, what are the criteria for selecting topics and sources to be emphasized? Yes, I admit to always nervous about extensive use of primary refs.--Smokefoot (talk) 14:19, 12 January 2017 (UTC)

@Smokefoot: re this edit of yours, the solvents listed are those in the CRC Handbook. Your change makes it sound like there is solubility in all organic solvents, which is unlikely to be true. As for your mention above of Mo(CO)₃(HMB), where is that in the article? As for content, DMacks has modified some of my additions here and elsewhere, which is fine. Collaboration works well. I plan to add to the pyramidal dication bit and also on HMB's use as a model compound for degradation of aromatic air pollutants. If you want to add 2350 more references, you can – I know I won't be. EdChem (talk) 14:40, 12 January 2017 (UTC)

solubility in all organic solvents, which is unlikely to be true. Response:

• We are not here to list minutia (in fact this touches on the whole point of my criticism, that the article risks descending into a list of randomly selected topics/articles selected according to unspecified criteria). Listing individual solvents is minutia, IMHO. It also verges on WP:NOTMANUAL - we are not a user's manual.
• Judgement is required by readers. My edit does not state all organic solvents.
• experienced chemists will immediately know that solubility in EtOH and pentane implies a host of solvents, so there is no point in listing them all. (and I would guess that one would have trouble finding an organic solvent that does not dissolve this stuff)

Wikipedia is a project with a mission and criteria. In any case, thanks for listening --Smokefoot (talk) 14:50, 12 January 2017 (UTC)

This experienced chemist notes that pentane was not listed. HMB is non-polar and aromatic so solubility in benzene is predictable, but given the stated insolubility in water, would solubility in ethanol be something a reader will infer / deduce / expect? What about highly polar organic solvents, given the water insolubility? In using the list provided by the CRC Handbook, aren't we going from the sources you prefer? Yet, you can replace their criteria with your own but criticise others for the same types of judgements? True, you do not say all organic solvents, you just say "insoluble in X, soluble in Y" and assume some Y is understood... which it will be by chemically-knowledgeable readers, but not all readers are. I maintain that the change sounds like all organic solvents. Given that the solvents from CRC are in the infobox, at least changing your comment to some organic solvents would be a reasonable compromise. EdChem (talk) 15:09, 12 January 2017 (UTC)

Ok, thanks for listening. I would defer to your minutia list than "some solvents" because it is going to be soluble in all of them and your wording sounds otherwise. --Smokefoot (talk) 15:18, 12 January 2017 (UTC)

Ready for DYK

Hi DMacks, the nomination of this article for DYK has been accepted, it is due to appear on the main page at midnight UTC on 21 to 22 February. I have made some tweaks following Corinne's GOCE work, see what you think. Before it goes onto the main page, I wonder if you would redraw / replace File:Oxidation of benzene to its dication.jpg – the grey background behind the benzene looks poor and, while PD, it is from the image at the journal home page and a proper re-drawing would be preferable, in my opinion. Also, the hook has been promoted without the image. We can request this be reconsidered if we like... do you think it is worth doing? EdChem (talk) 02:07, 20 February 2017 (UTC)

I'll redraw that one in a few hours. I would think an image is a nice addition, especially something that looks "pretty" or novel, since otherwise the article topic sounds like it would be either dry or essoteric. DMacks (talk) 15:13, 21 February 2017 (UTC)

@EdChem: More importantly, real life got in my way and I couldn't get back to the discussion of the choice of hooks:

a single carbon is bonded to six other atoms in an "unprecedented" pyramidal structure?

is still poor because it sounds like it's the pyramidal structure that is the unprecedented aspect. But instead it's the C-to-6-C that is unprecedented. DMacks (talk) 15:20, 21 February 2017 (UTC)

@DMacks: Well, we have some more time on this one. A discussion at WT:DYK#Queue 1 has led Gatoclass to move the hook to the lead / image slot in a later prep set. It will now run at 12 noon (UTC) on 24 February and is in Prep 6. While we are technically able to edit prep sets, it is not appropriate for us (as nominators) to modify our own hook. However, it will need editing to insert "(pictured)" anyway, so we can easily make a request at WT:DYK and have it tweaked so long as the content / underlying facts are unchanged. I do agree with your point about the novelty being the C-to-6C aspect. What do you think of:

C
₆(CH
₃)²⁺
₆, dication of hexamethylbenzene

• (ALTa): ... that the hexamethylbenzene dication has a pyramidal structure (pictured) where a single carbon atom is bonded to an "unprecedented" six other carbon atoms?
• (ALTb): ... that the pyramidal structure of the hexamethylbenzene dication (pictured) has a central carbon atom bonded to an "unprecedented" six other carbon atoms?

Thanks for planning to update the image I mentioned, and also thanks to Gatoclass for moving the hook for this article to an image slot. EdChem (talk) 20:57, 21 February 2017 (UTC) PS: Edited to add an alternative wording – any other suggestions welcome.  :) EdChem (talk) 21:01, 21 February 2017 (UTC)

I'm having a WP:V problem here. File:Oxidation of benzene to its dication.jpg is for benzene, and our article here says that the hexamethyl analog would be expected to behave similarly. That claimed analogy is cited to doi:10.1002/anie.201608795, but that article only says that benzene itself behaves this way. I don't see that ref making the stronger statement that the hexamethyl analog would, and they don't make the dication by that route. Do you know of a ref that makes the direct comparison of this mechanism/intermediate? DMacks (talk) 05:47, 23 February 2017 (UTC)

The image is only about benzene, and is solidly sourced, so I am unsure what WP:V issue there is with that image. I note that, if the hexamethyl derivative does not behave similarly, then on what basis is every source calling the pyramidal cation the hexamethylbenzene dication? I would imagine that cyclic voltammetry would establish the two-electron oxidation and its irreversibility absent very rapid scan rates, and didn't the ref mention in passing that they (or others) had been unsuccessful preparing the dication from hexamethylbenzene directly? In any case, the image and preceding text are solid that benzene undergoes the rearrangement on oxidation, so the option of modifying the text following the image exists if you think it is unjustified. Several of the popular science sources assert the dication was prepared directly from hexamethylbenzene rather than using the epoxide of hexamethyl Dewar benzene, but I wouldn't use them as the Angew. Chem. paper is clear on what was actually done. Thoughts, DMacks? EdChem (talk) 14:40, 23 February 2017 (UTC)

Our article currently says "Direct, two-electron oxidation of hexamethylbenzene would be expected to result in a near-identical rearrangement", which means that both the mechanistic process and the outcome are the equivalent for hexamethyl and benzene itself. We then say (as you note) that"attempts to synthesise it in bulk by this method have been unsuccessful" meaning that it actually doesn't (yet) work for hexamethyl. So we can't say "would be expected" unless we have some WP:RS that says that. We can certainly say, "benzene itself can be converted directly to its dication by two-electron oxidation, and the product spontaneously rearranges to a pentagonal-pyramid", but details of that rearrangement are not relevant to hexamethyl without a cite. At most I would support a diagram [benzene] --[conditions]--> [pyramidal dication] (no intermediate) for comparison of what citedly doesn't work for the hexamethyl case at hand. DMacks (talk) 21:54, 24 February 2017 (UTC)

Either ALTa or ALTb sound fine to me. ALTa seems more technically correct (proving the structure, which confirms the obvious geometric details of it) but ALTb sounds more catchy (taking as a given the structure and more focus on the novel aspect of the bonding). DMacks (talk) 05:51, 23 February 2017 (UTC)

@Gatoclass:, would you please have a look at ALTa and ALTb and use one of them as a replacement for the present hook which, as DMacks has noted, is ambiguous on what is actually unprecedented, whereas these are not. Thanks. EdChem (talk) 14:40, 23 February 2017 (UTC)

 Done Gatoclass (talk) 14:47, 23 February 2017 (UTC)

GA Review

This review is transcluded from Talk:Hexamethylbenzene/GA1. The edit link for this section can be used to add comments to the review.

Reviewer: Double sharp (talk · contribs) 03:19, 8 January 2018 (UTC)

This looks like a very interesting, complete, and well-referenced article that I shall be very happy to rescue from its eight-and-a-half-month wait for a review. ^_^ Double sharp (talk) 03:19, 8 January 2018 (UTC)

(I will probably have more time to do the review tomorrow, or failing that over the weekend, but for now I have done a preliminary read-through and have found it very engaging. If it is a tad technical for the average reader, that probably cannot be helped without losing information, and there is already some information that they can sink their teeth into first.) Double sharp (talk) 15:11, 9 January 2018 (UTC)

Double sharp, I do have a tendency to prefer technically-precise language, but I also recognise that WP has an audience with a broad range of backgrounds, and I am happy to redraft / modify sections to try to improve accessibility. Please just point out where you think it is desirable. EdChem (talk) 23:10, 12 January 2018 (UTC)

Double sharp: FYI, the expansion of this article was a collaborative effort from me and DMacks, and I think the GA credit (assuming it passes, of course) probably belongs to both of us. EdChem (talk) 23:14, 12 January 2018 (UTC)

GA review – see WP:WIAGA for criteria

1. Is it well written?

   A. The prose is clear and concise, and the spelling and grammar are correct:

   I have read through the prose, and I find that if one reads it paying a reasonable amount of attention, it is actually very clear, with helpful links provided for the not so chemistry-savvy. Double sharp (talk) 15:03, 14 January 2018 (UTC)

   B. It complies with the manual of style guidelines for lead sections, layout, words to watch, fiction, and list incorporation:

2. Is it verifiable with no original research?

   A. It contains a list of all references (sources of information), presented in accordance with the layout style guideline:

   B. All in-line citations are from reliable sources, including those for direct quotations, statistics, published opinion, counter-intuitive or controversial statements that are challenged or likely to be challenged, and contentious material relating to living persons—science-based articles should follow the scientific citation guidelines:

   C. It contains no original research:

   D. It contains no copyright violations nor plagiarism:

3. Is it broad in its coverage?

   A. It addresses the main aspects of the topic:

   B. It stays focused on the topic without going into unnecessary detail (see summary style):

4. Is it neutral?

   It represents viewpoints fairly and without editorial bias, giving due weight to each:

5. Is it stable?

   It does not change significantly from day to day because of an ongoing edit war or content dispute:

6. Is it illustrated, if possible, by images?

   A. Images are tagged with their copyright status, and valid fair use rationales are provided for non-free content:

   B. Images are relevant to the topic, and have suitable captions:

7. Overall:

   Pass or Fail:

I feel quite confident in awarding a richly deserved green plus for this extremely enjoyable read. Thank you, EdChem and DMacks! (I think the original message only went to you because you were the nominator; I'll be sure to inform DMacks as well.) Double sharp (talk) 15:03, 14 January 2018 (UTC)