How can I perform a Michael Addition on a hindered a,b-conjugated system?

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What are the best conditions for a Michael addition?

I want to perform Michael addition (with O, N and S) to a a,b-conjugated system. I know that in the presence of copper, I can selectively have 1,4-addition. This works even in the presence of a...

04 May 2013 523 13 View

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Basis set and input instruction to calculate HOMO and LUMO using Orca for Imidazolium based organic salts?

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How can I get my Granzyme B flow cytometry stain to be consistent?

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Posthoc test lettering in JAMOVI?

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Frank Kayser

This very much depends on what nucleophile you are planning on using... Assuming that you are looking for a C-C bond forming reaction, I have had good luck in the past with Mukaiyama-type additions, using a silyl enol ether in the presence of TiCl4. For organocuprates, Lipshutz' higher order cuprates are the way to go, see e.g.: Synlett (1990), (3), 119. Synthesis (1987), (4), 325. Tetrahedron (1984), 40(24), 5005.

Xin Zhou

This depends on what kind of hindrance your system owns, and the structure of the nucleophile.