The Benary reaction is an organic reaction. In 1931 Erich Bénary discovered that ò-(N,N-dialkylamino)-vinyl ketones reacted with Grignard reagents in a 1,4-addition to give ñ,ò-unsaturated ketones, ñ,ò-unsaturated aldehydes and ñ,ò-unsaturated esters as well as poly-unsaturated ketones and aldehydes after hydrolysis of the reaction intermediate and elimination of a dialkylated amine.