Pyridinium Trifluoro Acetate Mediated Synthesis of 3,4-Dihydropyrimidin-2(1H)-ones and Tetrazolo[1,5-a]pyrimidine-6-carboxylates

A simple and economic synthesis of 3,4-dihydropyrimidin-2(1H)-ones using pyridinium triflate as catalyst under microwave condition was attempted with an easy work-up protocol. Further tetrazolo [1,5-a] pyrimidine-6-carboxylates were synthesized by three-component coupling reaction of β-ketoesters with a mixture of aromatic aldehyde and 5-aminotetrazole. The products were well characterized with IR, NMR (1H and 13C NMR) and mass spectrometry.