反应详情

A solution of 10.9 g (0.04 mol) of methyl 5-(2-bromoacetyl)-2-hydroxybenzoate in 100 ml of dry tetrahydrofuran is added dropwise over 4 hours to a stirred solution of 7.1 g (0.04 mol) of 1-(2-methylphenyl)piperazine and 4.0 g (0.04 mol) of triethylamine in 75 ml of tetrahydrofuran at room temperature. Stirring is continued for 2-12 hours or until the theoretical amount (7.3 g) of triethylamine hydrobromide precipitates. The precipitates is removed by filtration and the filtrate is evaporated to dryness. Addition of 2 equivalents of methanolic HCl and precipitation by addition of ethyl ether at room temperature affords the crude methyl 2-hydroxy-5-[2-[4-(2-methylphenyl)-1-piperazinyl]acetyl]benzoate dihydrochloride (9.4 g). Attempts to purify this product by recrystallization frequently led to decomposition and were subsequently avoided.

1. customprecipitates
2. customThe precipitates is removed by filtration
3. customthe filtrate is evaporated to dryness