Guanidine Hydrochloride (GuHCl) Catalysed Microwave-Mediated Solvent- and Metal-Free Synthesis of Pyrimido[1,2-a]benzimidazole from Aryl Aldehyde and Aryl Methyl Ketone

The rapid, eco-friendly, solvent- and metal-free microwave-assisted synthesis of pyrimido[1,2- a ]benzimidazole in high yields was achieved using the green organocatalyst guanidine hydrochloride using simple and inexpensive starting materials.