Ethyl Acetate → tert-butyl 7-(1-(tert-butoxycarbonyl)-2-methyl-1H-benzo[d]imidazol-6-yl)-2,3-dihydrobenzo[f][1,4]oxazepine-4(5H)-carboxylate

Participants

Reaction Conditions

Reaction Steps

A suspension of 1,1-dimethylethyl 6-bromo-2-methyl-1H-benzimidazole-1-carboxylate (11.3 g, 36 mmol), (4-{[(1,1-dimethylethyl)oxy]carbonyl}-2,3,4,5-tetrahydro-1,4-benzoxazepin-7-yl)boronic acid (11.7 g, 40 mmol), dichloro[1,1-bis(diphenyl-phosphino]ferrocenepalladium (II) dichloromethane adduct (3.0 g, 10 mol %) in dioxane (115 mL) and water (28.5 mL) was degassed with nitrogen, and then diisopropylethylamine (18.6 g, 144 mmol) was added. The reaction mixture was stirred at 90° C. for 220 min, cooled to room temperature, and concentrated. Column chromatography on silica of the residue (gradient 25-30% ethyl acetate in hexane) afforded 1,1-dimethylethyl 7-(1-{[(1,1-dimethylethyl)oxy]carbonyl}-2-methyl-1H-benzimidazol-6-yl)-2,3-dihydro-1,4-benzoxazepine-4(5H)-carboxylate (13.2 g, 76% yield) as an amorphous solid. MS (EI) for C27H33N3O5: 480 (MH+).

Provenance & Evidence