Thiono and Dithio Esters, 40. - Reactions of Dithionomalonic Esters with Nucleophilic Nitrogen Bases

Article abstract of DOI:10.1002/ardp.19883211208

Dithionomalonic esters 1, obtained from malonitrile via malonodiimidium salts 5 by thiolysis, react with amines under elimination of H2S to form the 3-amino-thioacrylic O-esters 11.The alkali salts of 1 condense with amines to give the malonodithioamides 12 by loss of 2 molecules of alcohol.Oxidative cyclization of 11 leads to the isothiazoles 16-18.Reaction of 1 with hydrazines gives rise to the pyrazoles 20-22; with amidines the pyrimidines 23 and 24 were obtained.