Microwave Assisted Synthesis of some New Chromene Derivatives

An efficient synthesis of some new 4-(benzo [d] -1,3-dioxo-5-yl)-[2,3-c]-N-aryl pyrolo-1,3-dione-3,4,5,6-tetrahydro-2H-benzo[h] chromene derivatives (4a-h) via Diels-Alder reaction of 2-piperonylidene-1- tetralone (1) and N- aryl maleimides (3a-h) under microwave irradiation was described.
The yield have been improved (- 84 92%) and the reaction time reduced from hours to few minutes through the use of dichloromethane as solvent and aluminum chloride as catalyst.
All prepared compounds were confirmed by the available physical and spectral methods.