Turkish Journal of Chemistry, Vol.40, No.3, 434-440, 2016
An efficient one-pot, three-component synthesis of 6-cyano-hexahydro-4 H-thieno[3',2':5,6]pyrimido[1,2-a]quinoline-2-carboxylates and their spiro derivatives from beta-enaminones
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 beta-enaminone 3 with the corresponding alpha, beta-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 beta-enaminone 3 with the corresponding 3-cyanomethylidene-2-oxoindoles 11a-d in refluxing EtOH.
Keywords:Cyclic enaminones;alpha;beta-unsaturated nitriles;hexahydroquinolines;multicomponent reaction;spirooxindoles