反应详情

A suspension of 2.59 g (0.01 mole) of 4-(3,5-dichloro-4-methylphenyl)-4-oxo-2-butenoic acid and 1.60 g (0.01 mole) of potassium O-ethyl dithiocarbonate in 40 ml of water was stirred at room temperature for 3 hours. At the end of this time, the mixture was ice-cooled, acidified by the addition of concentrated hydrochloric acid and then extracted with diethyl ether. The extract was subjected to column chromatography through silica gel, to give 3.60 g (yield 94.5%) of the desired 4-(3,5-dichloro-4-methylphenyl)-2-ethoxythiocarbonylthio-4-oxobutenoic acid, melting at 126°-128° C.

1. temperaturecooled
2. extractionextracted with diethyl ether