反应详情

The procedure is as in Example 4 for the preparation of ethyl 6-phenyl-6-oxo-5-methylthio-2-dimethylamino-2,4-hexadienoate, starting with N-(3-dimethylamino-3-ethoxycarbonylpropenylidene)-N-methylmethanaminium tetrafluoroborate (10.6 g), a 2M ethanolic solution of sodium ethylate (18.5 cc) and 2-[2-(methylthio)acetyl]naphthalene (8 g) in ethanol (50 cc). After purification by chromatography on a silica column with a mixture of cyclohexane and ethyl acetate (50:50 by volume) as eluent, ethyl 2-dimethylamino-5-methylthio-6-(2-naphthyl)-6-oxo-2,4-hexadienoate (5 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 (50:50 by volume) as eluent