反应详情

The procedure is as in Example 4 for the preparation of ethyl 6-phenyl-6-oxo-5-methylthio-2-dimethylamino2,4-hexadienoate, starting with N-(3-dimethylamino-3-ethoxycarbonylpropenylidene)-N-methylmethanaminium tetrafluoroborate (11.4 g), a 2M ethanolic solution of sodium ethylate (20 cc) and α-methoxyacetophenone (6 g) in ethanol (50 cc). After purification by chromatography on a silica column with a mixture of dicholoromethane and ethyl acetate (50:50 by volume) as eluent, ethyl 2-dimethylamino-5-methoxy-6-oxo-6-phenyl-2,4-hexadienoate (8.1 g) is obtained, 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 dicholoromethane and ethyl acetate (50:50 by volume) as eluent