Michael addition

Also known as: Michael reaction

Schematic of the Michael addition. Reagents: Michael donor - activated methylene (diethyl malonate), Michael acceptor - conjugated olefin (ethyl cinnamate), base catalyst, acid work-up. Product: Michael adduct - addition product. Comments: The reagents could be made of a combination of different EWGs.

The Michael addition is an organic reaction used to convert an activated methylene and a conjugated olefin to the corresponding addition product using a base catalyst followed by an acid work-up. The activated methylene is essentially a methylene bonded to electron withdrawing groups that would stabilize the negative change that forms after deprotonation by the base. This deprotonation results in an enolate which in turn does a 1,4 addition to the conjugated olefin. An acid work-up then provides the final Michael addition product.[1]


Mechanism of the Michael addition. Note: For simplisity we have shown the mechanism using, diethyl malonate, ethyl cinnamate, and sodium ethoxide, the reagents used in the original Michael paper from 1887.


Michael, A. J. Prakt. Chem. 1887, 35, 349–356.