Talk:Ylide

Latest comment: 5 months ago by 73.223.72.200 in topic Carbon monoxide?

How do you pronounce Ylide?

edit

Is it like "Why-lide" or "Elide" or "Illide"? Or is it something totally different?RSido 21:45, 3 May 2007 (UTC)Reply

I think it's pronounced "EE-lide" because it's a combination of -yl (as in carbonyl), pronounced "ill", and -ide (as in chloride). I looked it up and couldn't find proof, but Ylangylang also begins with "EE". Shalom Hello 22:11, 19 September 2007 (UTC)Reply

Ylide is pronounced ILL-ide (long i); see the OED, if you can figure out their pronunciation guide. The Brits generally use ylid, which is pronounced with a shorter i, as ILL-id. 30 April, 2008. —Preceding unsigned comment added by 24.180.105.143 (talk) 00:29, 1 May 2008 (UTC)Reply

Functional group

edit

In what way do you want an ylide to be an FG? ChristianB 22:21, 1 December 2007 (UTC)Reply

Ylide?

edit

Is it really spelled with an E by some in the U.S.? I'm a molecular biology Ph.D. student (American) and I've never seen it as anything except ylid. Not that this means much... --aciel (talk) 01:13, 16 December 2007 (UTC)Reply

I've always seen it as ylide, and that's the way it's spelled in a couple of IUPAC glossaries.[1] --Itub (talk) 12:21, 17 December 2007 (UTC)Reply
I've always seen it as ylide also. When I first read this article, I thought ylid was a typo as I've never seen it spelled that way in textbooks. --129.93.41.213 (talk) 02:23, 8 October 2009 (UTC)Reply

Pentavalent Nitrogen?

edit

Why is there a nitrogen with 5 covalent bonds in one of the mechanisms? —Preceding unsigned comment added by 86.31.115.188 (talk) 01:33, 20 February 2008 (UTC)Reply

Thanks for spotting the error, the image is updated. V8rik (talk) 17:49, 20 February 2008 (UTC)Reply

Nitro compounds

edit

Are nitro compounds considered ylids? They fall within the definition given in the article, and are very common, yet are not mentioned.

Ben (talk) 21:25, 12 July 2008 (UTC)Reply

Relation to zwitterions

edit

Are ylides not simply a special case of zwitterions? This is not mentioned on either page. 150.203.35.113 (talk) 07:42, 19 May 2009 (UTC)Reply

Clarification?

edit

Can we get some agreement on the argument currently taking place on the article's page regarding whether or not a stabilized ylide is reactive with both carbonyl species? The "NO IT IS NOT" is rather ridiculous. —Preceding unsigned comment added by 69.209.123.245 (talk) 20:37, 12 October 2010 (UTC)Reply

The section in question here does need some re-writing. The text as it stands is an over simplification and somewhat misleading. Consider, for example, that triphenylphosphonium benzylide (a "stabilized" ylide) does react with benzophenone (a stabilized ketone!) to give the triaryl substituted olefin. (see Journal of the Chemical Society, Perkin Transactions 1: Organic and Bio-Organic Chemistry, (4), 849-58; 1984) Or that triphenylphosphonium carboethoxy stabilized ylides do react with the ketone moiety of phenanthraquinone (albeit an activated ketone) (see Can. J. of Chem. 1964, 42, 190.) A good summary of this reactivity is available in "Ylides and Imides of Phosphorus" by A. William Johnson (1993) John Wiley & Sons, NY,ISBN 0-471-52217-1. Also, and very importantly, a phosphonate-stabilized carbanion of a Horner-Wadsworth-Emmons reaction is not an ylide (phosphonium ylide). Perhaps the original author here would want to revise his (or her) text. Pnicto-boy (talk) 21:36, 13 October 2010 (UTC)Reply

Wrong example

edit

Note that the Phosphonium example, according to the Gold Book, is not an ylide (electron sextet). [2]--Wickey-nl (talk) 17:01, 18 December 2010 (UTC)Reply

I assume this is the GoldBook ref you meant for the def of the term "ylide"? I think you're mis-reading it: the Wittig/phosphonium-ylide is not sextet and it is not a 1,3-dipole. The specific GoldBook def is 1,2-dipole, "i"f X is a second, third, etc. row element uncharged canonical forms are available RmX=YRn", etc. I think the "e.g." in the def is for what is, not for the preceding sentence of what isn't. But it doesn't matter what I think so much... IUPAC defines a phosphonium ylide for us. DMacks (talk) 17:10, 18 December 2010 (UTC)Reply
I saw it, just before I read your answer. And oversaw the only. The ylide lemma is quite messy.--Wickey-nl (talk) 09:24, 19 December 2010 (UTC)Reply

Why N+–C form?

edit

How is the N+–C form rationalized in Lewis structure theory? Normally while drawing different resonance structures, one would prefer those where negative formal charges are on the most electronegative atom. However, nitrogen is more electronegative than carbon. Similar issue with oxygen. Should the article stress that phosphonium ylides are by far the most common/stable type? — Preceding unsigned comment added by 2A02:1812:1126:5D00:5940:6D91:274C:533E (talk) 08:06, 12 September 2023 (UTC)Reply

Carbon monoxide?

edit

Is carbon monoxide considered an ylide? It seems to satisfy the definition, and is such an obvious example that the article ought to mention it and specify whether it is considered one. 73.223.72.200 (talk) 05:08, 16 June 2024 (UTC)Reply