Reactivity of the Pyrimidine Nitrogen Atom toward an Acetal Moiety: Formation­ of 3-Ethoxy-2,3-dihydroimidazo[1,2-c]pyrimidines by Intramolecular Cyclization of N-(2,2-Diethoxyethyl)pyrimidine-4-amines

Abstract

A new protocol was developed for the synthesis of 2,3-dihydroimidazo[1,2-c]pyrimidines, based on an intramolecular reaction between a pyrimidine nitrogen atom and an acetal moiety in the presence of boron trifluoride etherate. The method was expanded to permit the synthesis of the triheterocyclic imidazo[1,2-c]pyrazolo[4,3-e]pyrimidine system.

Key words

acetals - cyclizations - heterocycles - polycycles - pyrimidines - imidazoles

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