Cyanoacetylation of 5-Aminopyrazole: Synthesis of 2-(1-Aryl-4- substituted pyrazolo[3,4-d]pyrimidin-6-yl)acetonitrile Derivatives

Abstract

N1-Substituted-5-amino-4-cyanopyrazoles were cyanoacetylated with a mixture of cyanoacetic acid and acetic anhydride. Cyclization with POCl3 gave 4-chloro-pyrazolo[3,4-d]pyrimidine derivatives. From the reaction with hydrazine and arylhydrazines, the hydrazinyls and their oxidized forms, the azo products, were obtained. The structure of the compounds obtained has been confirmed by 1H and 13C NMR spectroscopy.