Diisopropylethylamine → 1,1-dimethylethyl 7-{4-[(methyloxy)carbonyl]phenyl}-2,3-dihydro-1,4-benzoxazepine-4(5H)-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a solution of 4-(methoxycarbonyl)phenylboronic acid (6.0 g, 33 mmol), potassium bicarbonate (9.1 g, 92 mmol), 1,1-dimethylethyl 7-bromo-2,3-dihydro-1,4-benzoxazepine-4(5H)-carboxylate (10 g, 31 mmol) and DIPEA (16 mL, 92 mmol) in dioxane (27 mL) and water (3 mL) was added dichloro[1,1-bis(diphenylphosphino]ferrocenepalladium (II) dichloromethane adduct (1.3 g, 1.8 mmol). The biphasic mixture was then heated at 90° C. for 2 h then partitioned with ethyl acetate and 1M hydrochloric acid. The organic layer was washed with 1M sodium hydroxide solution then dried over anhydrous magnesium sulfate, filtered and concentrated. The residue was purified by silica gel column chromatography (25% ethyl acetate in hexanes) to provide 1,1-dimethylethyl 7-{4-[(methyloxy)carbonyl]phenyl}-2,3-dihydro-1,4-benzoxazepine-4(5H)-carboxylate (7.5 g, 64% yield) as a pale yellow solid. MS (EI) for C26H23FN6O3: 384 (MH+).

Provenance & Evidence