An Efficient Synthesis of New 3,4-Dihydropyrimidin- 2(1H)-ones Incorporating a Phenyl Moiety at C-5 and C-6 Catalyzed by TMSCl and Co(OAc)₂.4H₂O

Abstract

New 3,4-dihydropyrimidin-2-ones having a phenyl moiety at C-5 and C-6 have been prepared by a microwave-assisted Biginelli–like reaction by a three-component, one-pot condensation of an aromatic aldehyde, deoxybenzoin and urea, or thiourea using TMSCl and Co(OAc) ₂ .4H ₂ O as an efficient Lewis acid catalyst.

Keywords:

• Biginelli–like reaction
• Co(OAc)₂.4H₂O
• 3,4-dihydropyrimidin-2-one
• microwave-assisted
• TMSCl

Notes

∗ Reaction condition: 3-methoxybenzaldehyde 5 mmol, deoxybenzoin 5 mmol, urea 15 mmol, P = 300 W, DMF.

∗ Reaction condition: 3-methoxybenzaldehyde 5 mmol, deoxybenzoin 5 mmol, urea 15 mmol, Co(OAC)₂.4H₂O 0.25 mmol, and TMSCl 2.5 mmol, DMF.

∗ Reaction condition: aromatic aldehyde 5 mmol; ketone or β-ketoester 5 mmol; urea15 mmol or thiourea 12 mmol, Co(OAc)₂.4H₂O 0.25 mmol and TMSCl 2.5 mmol, DMF, P = 300 W.