Synthesis of 3,5-Disubstituted Pyrazoles via Cope-Type Hydroamination of 1,3-Dialkynes

Abstract

An efficient method for the synthesis of 3,5-disubstituted pyrazoles is described. The reactions of 1,3-dialkynes with hydrazine proceeded smoothly in dimethyl sulfoxide under mild reaction conditions to produce 3,5-disubstituted pyrazoles in satisfactory to excellent yields. A one-pot procedure of the transformation has been developed.