One-pot synthesis of pyrano[2,3-d]pyrimidinone derivatives using a newacidic ionic liquid catalyst based on benzimidazole

Multicomponent reactions (MCRs) by virtue of their convergence, productivity, ease of execution and generally high yields of products have attracted considerable attention from the point of view of combinatorial chemistry. The first MCR was described by Strecker in 1850 for the synthesis of amino acids. However, in the past decade, there has been tremendous development in three- and four-component reactions and great efforts continue to be made to develop new MCRs 1.There is a continuous widespread interest in the synthesis of pyrano-pyrimidinones and coumarins because of the diverse biological properties associated with this system 2.Uracil and its derivatives, such as pyrano[2,3-d]pyrimidinones have received considerable attention over the past years because of their several biological activities such as, antibacterial, antiallergic, antimicrobial, tyrosine kinase, anti-inflammatory, analgesic, calcium channel antagonists, antihypertensive, tuberculostatic, antileishmanial, and antifungal 3.In this work, we have used a Bronsted acidic ionic liquid based on benzimidazole as a green and efficient catalyst for the preparation of pyrano[2,3-d]pyrimidinone derivatives. This method provided excellent yields during short reaction times. Also, the reusability of the catalyst was good.

Keywords:

Pyrano[2 , 3-d]pyrimidinone , Barbituric acid , Multicomponent reactions , Benzimidazole