反应详情

A mixture of 2-(3-(2-amino-1-benzimidazolyl)phenyl)-1,3,2-dioxaborinane (2.0 g, 6.82 mmol), 4-bromo-1,3,5-trimethylpyrazole (1.29 g, 6.82 mmol), tetrakis(triphenylphosphine)-palladium(0) (0.24 g, 0.20 mmol), sodium hydrogen carbonate (2.29 g, 27.3 mmol), water (27 ml) and 1,2-dimethoxyethane (54 ml) was stirred at reflux overnight. Aqueous sodium hydroxide (50 ml) was added and the mixture was extracted twice with ethyl acetate (50 ml). The crude extract was purified by chromatography using silica gel and a mixture of ethanol (4%) and dichloromethane as eluent. The product was isolated as the free base. Yield 0.60 g, 28%. M.p. 198-200° C.

1. temperatureat reflux overnight
2. extractionthe mixture was extracted twice with ethyl acetate (50 ml)
3. extractionThe crude extract
4. customwas purified by chromatography
5. additiona mixture of ethanol (4%) and dichloromethane as eluent
6. customThe product was isolated as the free base