A simple and efficient one-pot synthesis of novel thieno[3’,2’:5,6]pyrimido[1,2-a]quinoline-2-carboxylates (5a– d) and their spirooxindole derivatives (12a–d) was accomplished. Thus, the Michael addition reaction of the cyclic β-enaminone 3 with the corresponding α, β-unsaturated nitrile derivatives 4a–d in refluxing EtOH in the presence of piperidine afforded 5a–d in good yields. On the other hand, spirooxindole derivatives 12a–d were synthesized by the reaction of cyclic β-enaminone 3 with the corresponding 3-cyanomethylidene-2-oxoindoles 11a–d in refluxing EtOH. |
