Synthesis of New 2-(5-Aryl-3-styryl-4,5-dihydro-1<i>H</i>-pyrazol-1-yl)-4-(trifluoromethyl)pyrimidines

Abstract

A series of 2-(5-aryl-3-styryl-4,5-dihydro-1H-pyrazol-1-yl)-4-(trifluoromethyl)pyrimidines was synthesized by the cyclocondensation of 5-aryl-1-carboxamidino-3-styryl-4,5-dihydro-1H-pyrazoles with 4-alkoxy-1,1,1-trifluoroalk-3-en-2-ones. Efficient cyclizations catalyzed by Ti(Oi-Pr)4 or BF3·OEt2 gave the desired pyrimidines in good yields. The crystal structure of ethyl 3-[2-(5-phenyl-3-styryl-4,5-dihydro-1H-pyrazol-1-yl)-4-(trifluoromethyl)pyrimidin-6-yl]propanoate was determined.