Research Article

Copper Perchlorate Hexahydrate: An Efficient Catalyst for the Green Synthesis of Polyhydroquinolines under Ultrasonication

Table 1

Effect of amounts of catalyst, copper perchlorate hexahydrate with or without sonication for synthesis of 2,7,7-Trimethyl-5-oxo-4-phenyl-1,4,5,6,7,8-hexahydroquinoline-3-carboxylic acid ethyl ester.

EntryCu(ClO4)2·6H2O mol%With sonicationWithout sonication
Yield (%)Time (min)Yield (%)Time (min)

(1)0Nil90Nil90
(2)524601070
(3)1057402355
(4)1590203340
(5)2090203340