Acetals of lactams and acid amides. 38. Synthesis of pyrimidine and pyridine derivatives on the basis of the reaction of enamino amides with amide acetals

Abstract

Derivatives of 1-benzyl-4-pyrimidinones and 1-benzyl-6-pyrimidinones were synthesized by the reaction of β-cyano-3-N-benzylaminocrotonamide and α-cyano-β-aminocrotonic acid N-benzylamine with dimethylformamide diethylacetal. When 1-benzyl-5-cyano-6-(β-dimethylamino)vinyl-1,6-dihydro-4-pyrimidinone is heated in an alkaline medium, it is converted to 3-cyano-4-benzylamino-2-pyridone, from which a pyrido[1,2-a]pyrimidine derivative was synthesized. When 1-benzyl-5-cyano-4-(β-dimethylamino) vinyl-1,6-dihydro-6-pyrimidinone is heated in alkaline solution, it is converted to α-cyano-β-hydroxycrotonic acid N-benzylamide.