SYNTHESIS AND STRUCTURE OF 2-ARYLAMINO-SUBSTITUTED 4-(DICHLOROMETHYLIDENE)-3-NITRO-4H-PYRIDO[1,2-a]PYRIMIDINES

Abstract

The reaction of 4-substituted anilines with 3,4,4-trichloro-1,1-bis(3,5-dimethyl-1H-pyrazol-1-yl)-2-nitrobuta-1,3-dienes led to 1-arylamino-3,4,4-trichloro-1-(3,5-dimethyl-1H-pyrazol-1-yl)-2-nitrobuta-1,3-dienes, which under the action of 2-aminopyridines underwent heterocyclization to the corresponding 2-arylamino-substituted 4-(dichloromethylidene)-3-nitro-4H-pyrido[1,2-a]pyrimidines. The molecular structure of 4H-pyrido[1,2-a]pyrimidine containing the (4-ethoxyphenyl)amine substituent at position 2 was determined by X-ray structural analysis.