Acetals of lactams and acid amides. 41. Enamino amides in the synthesis of pyrimidine derivatives

Abstract

The reaction of α-cyano-β-dimethylaminomethyleneacrylamide with arylamines was used to synthesize α-cyano-β-arylaminoacrylamides, which react readily with dimethylformamide diethylacetal to give the corresponding N-dimethylaminomethylene derivatives. The latter undergo cyclization to 1-aryl-5-cyano-4-pyrimidinones when they are heated in dimethylformamide or acetic anhydride and to pyrimido-[5,4-c]quinolone derivatives when they are heated in glacial acetic acid.