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-t-butyloxycarbonylpropenylidene)-N-methylmethanaminium tetrafluoroborate (4.05 g), a 1.6M solution (8.8 cc) of butyllithium in hexane and ethyl (phenylthio)acetate (2.8 g) in tetrahydrofuran (65 cc). After purification by chromatography on a silica column with a mixture of cyclohexane and ethyl acetate (70:30 by volume) as eluent, 6-ethyl 1-tert-butyl 2-dimethylamino-5-phenylthio-2,4-hexadienedioate (2.6 g), m.p. 85°-88° C., is obtained.

1. customAfter purification by chromatography on a silica column
2. additionwith a mixture of cyclohexane and ethyl acetate (70:30 by volume) as eluent