Water → 1,1-dimethylethyl 7-acetyl-2,3-dihydro-1,4-benzoxazepine-4(5H)-carboxylate

Participants

Reaction Conditions

Reaction Steps

n-Butyllithium (2.5 Min hexane, 2.31 mL, 5.8 mmol) was added to a solution of 1,1-dimethylethyl 7-bromo-2,3-dihydro-1,4-benzoxazepine-4(5H)-carboxylate (1.56 g, 4.76 mmol) in tetrahydrofuran (20 mL) and the resulting mixture was stirred at −78° C. for one hour. A solution of N-methoxy-N-methylacetamide (0.97 g, 9.4 mmol) in tetrahydrofuran (5 mL) was added to the reaction mixture dropwise then warmed to room temperature and stirred for an additional hour. Water (50 mL) was added and the resulting mixture was extracted with ethyl acetate (3×40 mL). The combined organic extract was washed with water, then brine solution (80 mL each), dried over sodium sulfate, filtered, concentrated to give 1,1-dimethylethyl 7-acetyl-2,3-dihydro-1,4-benzoxazepine-4(5H)-carboxylate (1.34 g, 97% yield); MS (EI) for C16H21NO4: 292 (MH+).

Provenance & Evidence