Sodium ethoxide → Ethyl 2-dimethylamino-6-(4-fluorophenyl)-5-methylthio-6-oxo-2,4-hexadienoate

Participants

Reaction Steps

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 g), a 2M ethanolic solution of sodium ethylate (21 cc) and α-methylthio-4-fluoroacetophenone (6.5 g) in ethanol (100 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-6-(4-fluorophenyl)-5-methylthio-6-oxo-2,4-hexadienoate (9 g) is obtained in the form of an orange-coloured oil, and is used in the crude state in the subsequent syntheses.

Provenance & Evidence