Hydrochloric Acid → Ethyl 4-thiomethylbenzoylformate

Participants

Reaction Steps

37.5 g (0.3 mol) of Thioanisol and 41.4 g (0.3 mol) of chloro-oxo-acetic acid ethyl ester dissolved in 200 ml of dichloromethane are added dropwise to a suspension of 60 g (0.45 mol) of aluminum trichloride in 350 ml of dichloromethane at 0° C. The solution is stirred overnight at room temperature and then heated to reflux for two hours. After cooling to room temperature, the reaction mixture is poured on a mixture of 100 ml conc. HCl and ice/water. After extraction with dichloromethane, the organic phase is washed with water and sodium bicarbonate and dried over magnesium sulfate. The salt is filtered off and the solvent distilled to give 52.3 g (78%) of (4-methylsulfanyl-phenyl)-oxo-acetic acid ethyl ester as a yellow oil. This oil is used for the next step without further purification. The structure is confirmed by the 1H-NMR spectrum (in CDCl3). δ[ppm]: 7.87 (d,2H), 7.24 (d,2H), 4.39 (q,2H), 2.48 (s,2H), 1.37 (t,3H).

Provenance & Evidence