Green Approach to the Synthesis of Polyfunctionalized Pyrazolo[4′,3′:5,6]pyrido[2,3-d]pyrimidines via Microwave-Assisted Multicomponent Reactions in Water Without Catalyst

Abstract

A green approach to the synthesis of polyfunctionalized pyrazolo[4′,3′:5,6]pyrido[2,3-d]pyrimidines was successfully realized via multicomponent reactions of aldehydes, 3-methyl-1-phenyl-1H-pyrazol-5-amine, and 1-methylbarbituric acid in water under microwave irradiation without catalyst. This protocol has the prominent advantages of environmental friendliness, short reaction time, excellent yields, low cost, easy operation, and broad scope of applicability.

Keywords:

• Green synthesis
• microwave irradiation
• pyrazolopyridopyrimidine
• water

ACKNOWLEDGMENTS

We thank the National Natural Science Foundation of China (No. 20672090 and 20810102050), the Key Item of Natural Science Foundation of Xuzhou Normal University (No. 07XLA04), the Preliminary Item of Xuzhou Normal University on National Natural Science Foundation of China (No. 08XLY04), the Science and Technology Foundation of Xuzhou (No. XM08C027), the Natural Science Foundation (09KJB150011) and Qing Lan Project (08QL001) of Jiangsu Education Committee, and the Open Foundation of Jiangsu Key Laboratory for Chemistry and Low-Dimensional Materials (JSKC07035) for financial support.