Studies with arylhydrazonopyridinones: Synthesis of new arylhydrazono thieno[3,4-c]pyridinones as novel D2T2 dye class; classical verse green methodologies

A variety of arylhydrazonopyridinones were prepared via heating cyanoacetamides with ethyl acetoacetate in absence of solvent under reflux conventionally or ultrasound irradiation or in a microwave oven. The formed products 5 and 6 could be readily converted to thienopyridones. Attempted addition of the latter to electron poor olefins afforded only arylhydrazonopyridinones.