Acrolein as a Synthon for Pyrimidinic Compounds. Reaction with Benzamidine

Abstract

Depending on the reaction conditions, a c r o l e i n ( s t a b i l i z e d by hydroquinone)r e a c t s with bemamidine t o give s e l e c t i v e l y tetrahydropyrimidine (4), dihydmpyrimidine(5) and pyrimidine (6) i n high y i e l d s .The r e a c t i o n of amidines with u,B-unsaturated carbony1 compounds i s an a t t r a c t i v e approach t o t h e synthesis of pyrimidinic r i n g systems.However, i n s p i t e of the s u b s t a n t i a l progress i n t h e 2 study of t h i s r e a c t i o n during t h e l a s t decade , a l l attempts t o u t i l i z e t h e parent o,B-unsaturated 3 carbonyl compound, acrolein, f a i l e d .Fast polymerization of acrolein i n t h e presence of strong bases probably accounts f a r t h i s f a i l u r e .Actually we are facing a problem of a t l e a s t two concurrent