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 (20 g), a 2M ethanolic solution of sodium ethylate (42 cc) and ethyl (phenethylthio)acetate (15.7 g) in ethanol (200 cc). Diethyl 2-dimethylamino-5-phenethylthio-2,4-hexadienedioate (22.8 g) is thereby obtained in the form of an orange-coloured oil, and is used in the crude state in the subsequent syntheses.