反应详情

30.1 g of methyl 2-tert-butoxycarbonylamino-3-nitrobenzoate [BAN], 40.8 g of potassium carbonate and 160 ml of acetonitrile were added to the acetonitrile solution in which unreacted 2-(4-methylphenyl)benzonitrile [MPB] and 2-(4,4-dibromomethylphenyl)benzonitrile as an analogue of BMB were contaminated, and the reaction was allowed to proceed at about 82° C. for about 5 hours under stirring. After cooling to room temperature, the precipitated crystals were filtered off, and the filtrate was concentrated to give methyl 2-[N-t-butoxycarbonyl-N-[(2′-cyanobiphenyl-4-yl)methyl]amino]-3-nitrobenzoate [BBN]. The concentrated material was dissolved in 190 g of methanol, and 106 g of concentrated hydrochloric acid was added dropwise thereto. The resulting solution was heated to a reflux temperature over 2 hours, and stirred for 2 hours under reflux, whereby, the reaction was allowed to proceed. The reaction solution was cooled, and precipitated crystals were collected by filteration and dried to give 35.1 g of methyl 2-[N-(2′-cyanobiphenyl-4-yl)methylamino]-3-nitrobenzoate [MBN] (yield relative to 2-(4-methylphenyl)benzonitrile [MPB] was 76.1%)

1. filtrationthe precipitated crystals were filtered off
2. concentrationthe filtrate was concentrated