Synthesis of Tetrahydrobenzimidazo[1,2-b]quinazolin-1(2H)-one and Tetrahydro-1,2,4-triazolo[5,1-b]quinazolin-8(4H)-one Ring Systems Under Solvent-Free Conditions

Tetraheterocyclic benzimidazo[1,2-a]quinazolin-4(1H)-one and tetrahydro-1,2,4-triazolo[5,1-b]quinazolin- 8(4H)-one were synthesized in relatively high yields by the condensation reaction of an aldehyde and a cyclic β-diketone with 2-aminobenzothiazole, 2-aminobenzimidazole or 3-amino-1,2,4-triazole without using any catalyst under solventfree conditions.