Several imidazo and pyrimido [1, 2-a] pyrimidinones of type and were synthesized through intramolecular cyclization of pyrimidines or pyrimidinones bearing a variety of β and γ- aminoalcohols at the 2-position. Ring closure of the pyrimidinones of type under Mitsunobu conditions lead to mixtures of both bicyclic regioisomers and. Treatment of pyrimidines of type with H2SO4 provided an efficient and operationally simple one-pot hydrolysis– ...