Effects of nanosized metal oxides on regio- and stereofeatures for the synthesis of dihydroazolopyrimidines

Abstract

Substituted dihydroazolopyrimidines 1 and 2 have been prepared by the multicomponent Biginelli reaction with urea isosteres, such as 3-amino-1,2,4-triazole and 5-aminotetrazole [1]. It has been established that the formation of dihydroazolopyrimidines requires a more hard reaction conditions (7-8 hours of reflux in DMF) and proved to be a less selective process than the classical Biginelli reaction leading to dihydropyrimidines. For the first time the effects of nanosized metal oxides (CuO, Al[2]O[3], ZnO, MgO, TiO[2]-SiO[2]), including the presence of chiral modifiers, on regio- and stereoselective features of the multicomponent synthesis of dihydroazolopyrimidines 1 and 2 have been studied.