反应详情

The procedure is as in Example 2 for the preparation of diethyl 2-dimethylamino-5-phenylthio-2,4-hexadienedioate, starting with N-(3-dimethylamino-3-ethoxycarbonylpropenylidene)-N-methylmethanaminium tetrafluoroborate (10 g), a 2M ethanolic solution of sodium ethylate (21 cc) and ethyl (4-isopropylbenzylthio)acetate (8.8 g) in ethanol (100 cc). After purification by chromatography on a silica column with a mixture of cyclohexane and ethyl acetate (80:20 by volume) as eluent, diethyl 2-dimethylamino-5-(4-isopropylbenzylthio)-2,4-hexadienedioate (8.8 g) is obtained in the form of an orange-coloured oil, and is used in the crude state in the subsequent syntheses.

1. customAfter purification by chromatography on a silica column
2. additionwith a mixture of cyclohexane and ethyl acetate (80:20 by volume) as eluent