2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-benzimidazole synthesis

Yield:-

Reaction Conditions:

with (1,1'-bis(diphenylphosphino)ferrocene)palladium(II) dichloride;potassium acetate in 1,4-dioxaneInert atmosphere;Reflux;

Steps:

49.iv
2-bromo-1 H-benzo[d]imidazole (177 mg, 0.9 mmol), bispinacolato diboron (250 mg, 0.99 mmol) and KOAc (265 mg, 2.7 mmol) were dissolved in dioxane (9 ml). After purging with N₂, Pd(dppf)CI₂ (37 mg, 0.045 mmol) was added. After stirring overnight at reflux temperature the reaction was cooled to room temperature the reaction mixture was diluted with some ethyl acetate (20 ml). The mixture was filtrated through a pad of celite and the solvent was evaporated under reduced pressure to give 2-(4,4,5,5-tetramethyl-1 ,3,2-dioxaborolan-2-yl)-1 H- benzofdlimidazole as a black oil. The crude product was used in the next step without further purification

References:

MSD OSS B.V.;HUISMAN, Ines;VAN DER STELT, Marcelis;WIEDENHOF, Wouter;BAKER-GLENN, Charles, Anthony, Graham;BLACKABY, Wesley, Peter;TRIVEDI, Naimisha WO2013/41457, 2013, A1 Location in patent:Page/Page column 65