Process for the preparation of gamma-vinylpyrrolidones.

摘要

Gamma-vinylpyrrolidones of the general formula I in which R<1> and R<2> are hydrogen or C1- to C8-alkyl, and R<3> is hydrogen, C1- to C20-alkyl, C3- to C8-cycloalkyl, aryl, C7- to C12-alkylaryl, C7- to C12-aralkyl or a heterocyclic radical are prepared by reacting gamma-vinylbutyrolactones of the general formula II in which R<1> and R<2> have the abovementioned meaning, with ammonia or primary amines of the general formula III R<3>-NH2 (III), in which R<3> has the abovementioned meaning, at temperatures from 150 to 350 DEG C and pressures from 0.1 to 200 bar, and gamma-vinylbutyrolactones II are prepared by reaction of 3-formyl-propionic acid esters of the general formula IV in which R<1> and R<2> are hydrogen or C1- to C8-alkyl, and R<4> is hydrogen, C1- to C20-alkyl, C3- to C8-cycloalkyl, aryl, C7- to C12-alkylaryl or C7- to C12-aralkyl with vinylmagnesium halides of the general formula V CH2=CH-Mg-X (V), in which X is chlorine, bromine or iodine, at temperatures from -30 to 100 DEG C and pressures from 0.001 to 10 bar in the molar ratio of V:IV of 0.3:1 to 3:1.