Gould-Jacob type of reaction in the synthesis of thieno[3,2-e]pyrimido[1,2-c]pyramidines: A comparison of classical heating vs solvent-free microwaveirradiation

Gould-Jacob type of reaction for the synthesis of thieno[3,2-e]pyrimido[1,2 -c]pyrimidines ((5) under bar) has been carried out conventionally by the c ondensation between 4-aminothieno[2,3-d]pyrimidines ((2) under bar) and die thyl ethoxymethyl-enemalonate ((3) under bar) via acyclic intermediates die thyl N-[5,6-disubstituted thieno[2,3-d]pyrimidin-4-yl]aminomethylenemalonat es ((4) under bar) and the results obtained were compared with single step microwave technique under solvent free conditions for the synthesis of 5.