Synthesis
The 7g 2 - (4-bromophenyl) - 1-phenyl-benzimidazole (0.02mole) adding 150mlTHF in, lower the temperature to -78 °C, at -78 ° C dropping under 12 ml (2.5M/L, 0 . 03mole) n-BuLi, thermal insulation 30 minutes, dropping 4.26g (0.041mole) methyl borate, reaction 2 hours after the reaction end of the water in the reaction solution of 50 ml, stirring 20 minutes, hydrochloric acid to adjust pH value to acidity, stirring 30 minutes, the reaction solution with ethyl acetate extraction three times, washing time combined with the organic layer, the organic phase is separated, turns on lathe does, solid with petroleum ether heat two times, filtering, to obtain solid intermediates kind of white 4-(1-Phenyl-1H-benzimidazol-2-yl)phenylboronic acid, yield 65percent.
