PS-TBD triggered general protocol for the synthesis of 4H-chromene,pyrano[4,3-b]pyran and pyrano[3,2-c]chromene derivatives of 1H-pyrazole and their biological activities

A general protocol has been developed for the facile construction of titled derivatives via three component reaction between 3-substituted phenyl-1H-pyrazole-4-carbaldehyde, malononitrile and various Michael donors in presence of 5 mol% polystyrene supported 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene（PS-TBD）. PS-TBD was reused for at least five runs with nearly constant catalytic activity. All compounds were screened for antimicrobial and antioxidant activities.