反应详情

Benzofuran-3-carboxylic acid (1.00 g, 6.17 mmol) was suspended in methylene chloride (20 mL), and oxalyl chloride (1.08 mL, 12.34 mmol) was added dropwise. To this reaction liquor, a catalytic amount of DMF (one drop) was added, and the reaction liquor was stirred for one hour at room temperature. The solvent was distilled off under reduced pressure, to obtain benzofuran-3-carboxylic acid chloride as a solid. The obtained acid chloride was suspended in 1,2-dichloroethane (20 mL), and (4-amino-3-chlorophenyl)acetic acid ethyl ester hydrochloride (1.54 g, 6.17 mmol) was added. The mixture was heated and stirred for 20 hours. The mixture was left to cool naturally to room temperature, and then the solvent was distilled off under reduced pressure. The obtained residue was purified by flash column chromatography (Flash Chromatography System from Biotage AB, column size: 40S, elution solvent: n-hexane:ethyl acetate=95:5 to 75:25), to obtain the title compound (2.08 g, 94%) as a solid.

1. distillationThe solvent was distilled off under reduced pressure