Talk:Hydrogen-bond catalysis

Latest comment: 5 years ago by 132.199.243.27 in topic Stereochemistry of the asymmetric Michael addition

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The article should be renamed to enantioselective hydrogen bond catalysis? What is the difference with acid catalysis or organocatalysis? V8rik (talk) 21:27, 23 October 2012 (UTC)Reply

Well, although a lot of work has been done on asymmetric hydrogen bond donors, I think it's good to have a page on activation via hydrogen bonds in general. The amount of information on asymmetric catalysis is simply a consequence of a lot of catalysis work focusing in this area. I agree that maybe there should be more focus on mechanism of activation rather than just a list of too many examples of asymmetric catalysis. I will continue to add to the page accordingly, and I appreciate your feedback.

The way I understand it, although stronger hydrogen bonds can activate electrophiles by partial protonation or resemble general acid mechanism, hydrogen bond catalysis is a distinct field per se and should be considered a subfield of organocatalysis. For example, I don't think asymmetric protonation is considered a form of hydrogen bond catalysis, nor should anion-binding be considered an acid catalysis mechanism. The two concepts definitely share similarities though.

Perhaps after I add a bit more information, if people think it's necessary, we can consider redistributing the information among the several growing organocatalysis articles. For example, I see that someone had started a thiourea catalysis stub.Richard Liu (talk) 00:19, 24 October 2012 (UTC)Reply

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Stereochemistry of the asymmetric Michael addition

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Hello chemists,

I think the stereochemistry of the product of first picture, which shows the "asymmetric Michael addition developed by Takemoto" of the page is wrong. I read a publication of Takemoto "Enantioselective Michael Reaction of Malonates to Nitroolefins Catalyzed by Bifunctional Organocatalysts" (J. Am. Chem. Soc. 2003, 125, 42, 12672-12673) in which he determined an enantiomeric excess of the other enantiomer.

Maybe someone else could check this too. I am pleased to hear your opinion.

The direct link to the publication: https://pubs.acs.org/doi/10.1021/ja036972z — Preceding unsigned comment added by 132.199.243.27 (talk) 01:10, 25 October 2019 (UTC)Reply