The general procedure for the synthesis of 4-fluoro-1-isopropyl-2-methyl-6-boronic acid pinacol ester-based-1H-benzo[d]imidazole from 6-bromo-4-fluoro-1-isopropyl-2-methyl-1H-benzo[d]imidazole and bis(pinacolato)diboron was carried out as follows: in a 500 mL single-necked flask, DMSO (100 mL), followed by sequential addition of 6-bromo-4-fluoro-1- isopropyl-2-methyl-1H-benzo[D]imidazole (20.0 g, 73.80 mmol), bis(pinacolato)diboron (27.6 g, 108.69 mmol), tricyclohexylphosphine (3.53 g, 12.61 mmol) and potassium acetate (21.3 g, 217.38 mmol) were added sequentially. After rapid addition of palladium acetate (1.5 g), the reaction flask was protected by passing nitrogen into the flask and subsequently heated to 90 °C under nitrogen atmosphere. After 3 hours of reaction, the reaction flask was cooled to room temperature and the reaction mixture was poured into 700 mL of water, stirred thoroughly and filtered under reduced pressure. The filter cake was washed twice with 100 mL of water and dried to give a light brown solid. The crude product was pulped with 50 mL of petroleum ether and 10 mL of ethyl acetate for 10 min, and was vacuum filtered to give a white solid (18.8 g, 80.3% yield).
![6-Bromo-4-fluoro-1-isopropyl-2-methyl-1H-benzo[d]imidazole](/CAS/GIF/1231930-33-8.gif)
