Michael reaction

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In organic chemistry, the Michael reaction or Michael addition describes a reaction between any Michael donor (α,α disubstituted carbonyls, nitrile, sulfone, etc., — electron-withdrawing groups) and any Michael acceptor (α,β-unsaturated carbonyls, nitrile, nitro, etc., — electron-withdrawing groups).[1][2] It belongs to the larger class of conjugate additions and is widely used for the mild formation of C–C bonds.[3] Many asymmetric variants exist[4][5] and depending on the conditions, Michael Additions can be diastereoselective and/or enantioselective.[6]

In this scheme, R and R' on the nucleophile (the Michael donor) represent electron-withdrawing substituents such as acyl and cyano groups, which make the adjacent methylene hydrogen acidic enough to form a carbanion when reacted with the base, B:. For the alkene (the Michael acceptor), the R" substituent is usually a ketone, which makes the compound an enone, but it can also be a nitro group or a sulfonyl methyl fluoride. The product is called a Michael adduct.