Microwave-Assisted Copper Powder-Catalyzed Synthesis of Azole-Fused Pyrimidinones

Title:Microwave-Assisted Copper Powder-Catalyzed Synthesis of Azole-Fused Pyrimidinones

Volume: 22 Issue: 1

Author(s): Pham Duy Quang Dao, Chan Sik Cho*, Son Long Ho and Ho-Sang Sohn

Affiliation:

• Department of Applied Chemistry, Kyungpook National University, Daegu 702-701,Korea

Keywords: Benzimidazole, β-bromo-α, β-unsaturated amide, copper powder, imidazole, pyrazole, pyrimidinone.

Abstract: Background: Azole-fused pyrimidinones have been synthesized and tested for biological activities. The present copper-catalyzed version will be attempted as an alternative synthetic method for such N-fused hybrid structures.

Objective: This research aims to develop a new synthetic method of azole-fused pyrimidinones from β-bromo-α,β-unsaturated amides and azoles (benzimidazole, imidazole and pyrazole).

Method: β-Bromo-α,β-unsaturated amides react with azoles in DMF at 100°C for 1 h in the presence of a catalytic amount of copper powder and base under microwave irradiation.

Result: β-Bromo-α,β-unsaturated amides are coupled and cyclized with azoles to give the corresponding azolefused pyrimidinones in moderate to good yields via tandem intermolecular C-N coupling and C-N formative cyclization by C-H activation.

Conclusion: This work provides a new method for synthesizing N-fused hybrid scaffolds such as benzimidazo[ 1,2-a]pyrimidin-2-ones, imidazo[1,2-a]pyrimidinones and pyrazolo[1,5-a]pyrimidinones from readily available starting compounds.

Cite this article as:

Quang Dao Duy Pham , Cho Sik Chan *, Ho Long Son and Sohn Ho-Sang, Microwave-Assisted Copper Powder-Catalyzed Synthesis of Azole-Fused Pyrimidinones, Current Organic Chemistry 2018; 22 (1) . https://dx.doi.org/10.2174/1385272821666170531122318