Water → HCID 86743584, compound

Participants

Reaction Steps

Acetyl chloride (1.2 cc) is added at a temperature of approximately 20° C., and in the course of 5 minutes, to a stirred solution, through which a stream of nitrogen is passed, of diethyl 2-hydroxy-5-phenylthio-2,4-hexadienedioate (5 g) and triethylamine (2.4 cc) in tetrahydrofuran (45 cc). Stirring is maintained for 2 hours at the same temperature. The mixture is taken up with water (100 cc) and dichloromethane (100 cc). The organic phase is separated off after settling has taken place, and the aqueous phase is extracted with dichloromethane (2×50 cc). The organic phases are combined, dried over anhydrous magnesium sulphate, filtered and concentrated to dryness at 40° C. under reduced pressure (20 mm Hg; 2.7 kPa). The oil obtained is dissolved in a mixture (10 cc) of cyclohexane and ethyl acetate (70:30 by volume), and poured onto silica (300 g) contained in a column 4 cm in diameter. Elution is performed with a mixture of cyclohexane and ethyl acetate (70:30 by volume), and the corresponding eluate is concentrated to dryness at 40° C. under reduced pressure (20 mm Hg; 2.7 kPa). Diethyl 2-acetoxy-5-phenylthio-2,4-hexadienedioate (4.5 g) is obtained in the form of an orange-coloured oil [Rf=0.50; thin layer chromatography on silica gel; eluent: cyclohexane/ethyl acetate (70:30 by volume)].

Provenance & Evidence