Hydrochloric Acid → n-(2,6-Dichloro-4-methoxycarbonylphenyl)-7-methoxy-2-(1-methylethyl)benzofuran-4-carboxamide

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Reaction Steps

2.0 g of triethylamine were added to a solution of 4.4 g of methyl 4-amino-3,5-dichlorobenzoate in 50 ml of tetrahydrofuran and the mixture was stirred (solution 1). In parallel to this, 4.7 g of 7-methoxy-2-(1-methylethyl)benzofuran-4-carboxylic acid were stirred at 80° C. for 3 h with 10.0 ml of thionyl chloride in 40 ml of toluene and the mixture was then evaporated in vacuo. About 20 ml of toluene were added to the residue and the solution was evaporated again in vacuo. The residue was then taken up in 50 ml of tetrahydrofuran and this solution was added dropwise at RT to the prepared solution 1. After reaction was complete, the mixture was stirred into about 200 ml of ice water, treated with 30 ml of 2 N hydrochloric acid and extracted with ethyl acetate. This extract was dried over calcined sodium sulfate and evaporated in vacuo. The residue was crystallized from toluene: m.p. 175° C.

Provenance & Evidence