(Phenylthio)acetic acid, cyclohexyl ester → 1-Ethyl 6-cyclohexyl 2-dimethylamino-5-phenylthio-2,4-hexadienedioate

Beteiligte Stoffe

Reaktionsschritte

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 (13.7 g), a 1.6M solution (33.1 cc) of n-butyllithium in hexane and cyclohexyl (phenylthio)acetate (12 g) in tetrahydrofuran (150 cc). After purification by chromatography on a silica column with a mixture of cyclohexane and ethyl acetate (80:20 by volume) as eluent, 1-ethyl 6-cyclohexyl 2-dimethylamino-5-phenylthio-2,4-hexadienedioate (9.7 g) is obtained, and is used in the crude state in the subsequent phases.

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