4-Toluenesulfonyl chloride → Methyl 3-chloro-2-(methylsulfanyl)prop-2-enoate

Participants

Reaction Steps

To a suspension of 21.4 g (535 mmol) of sodium hydride (60% in oil) in 200 ml of DMF was added dropwise a mixture of 25.8 g (214 mmol) of methyl 2-(methylthio)acetate and 26.5 g (428 mmol) of methyl formate under ice cooling and stirred at room temperature overnight. To the reaction mixture was added portionwise 27.0 g (141 mmol) of p-toluenesulfonyl chloride under ice cooling and stirred at room temperature for 1 hour. After dilution with tert-butyl methyl ether, the solution was washed sequentially with water and saturated NaCl solution, dried over anhydrous MgSO4, and concentrated. The residue was purified by silica gel column chromatography (hexane/ethyl acetate=5/1) to obtain 9.72 g of methyl 2-(methylthio)-3-(p-toluenesulfonyloxy)-2-propenoate and 1.88 g of methyl 3-chloro-2-(methylthio)-2-propenoate.

Provenance & Evidence