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 (2,4,6-trimethylbenzylthio)acetate (8.8 g) in ethanol (80 cc). After purification by chromatography on a silica column with a mixture of cyclohexane and ethyl acetate (70:30 by volume) as eluent, diethyl 2-dimethylamino-5-(2,4,6-trimethylbenzylthio)-2,4-hexadienedioate (6.44 g) is obtained in the form of a yellow 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 (70:30 by volume) as eluent