May 20, 2019, 06:48:29 PM
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Topic: Anyone have any examples of α,β-Unsaturated Carbonyls as Nucleophiles?  (Read 552 times)

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Offline workingundergrad1896

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I've been searching the literature for some time to try and find any conditions or examples of a reaction where an α,β-unsaturated carbonyl has been used as a nucleophile at the alkene, and not as an electrophile.

I realise this probably may not be a possible reaction, but I'm also unsure if my literature searching skills are just poor.

In particular I'm interested in an example where an α,β-unsaturated carbonyl has been used in a Prins or Prins-like reaction where the alkene is the nucleophile. However if anyone knows any examples or sources where an α,β-unsaturated carbonyl has been used as a pi nucleophile at the alkene, this would be of significant help.

Thanks.

Offline spirochete

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I'm pretty sure there is an example somewhere in Clayden Warren Greeves textbook where this kind of alkene is halogenated with Br2, in what they say is an electrophilic addition. Definitely not a Prins reaction, and also not the literature, but that's all I can think of.
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Offline CKabes

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What about the Baylis Hillman reaction?

Offline OrganicDan96

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What about the Baylis Hillman reaction?

in the Baylis-Hilman the alkene isn't really acting as a nucleophile, an enolate is which is formed by neucleophilic attack by the amine to the  α,β-unsaturated carbonyl.

Offline clarkstill

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NHC catalysis with enals, e.g. J. Am. Chem. Soc. 2004,  126, 44, 14370-14371

Offline TheUnassuming

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A little late to the party here, but depending on your substrate you might be able to pull off something like this:

https://www.sciencedirect.com/science/article/pii/0040403995010802

Its not exactly what I think you are looking for, but it does get attack at the beta carbon of the unsaturated carbonyl.
When in doubt, avoid the Stille coupling.

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