Triethylamine → Tert-butyl 4-bromo-5-oxoazepane-1-carboxylate

Participants

Reaction Steps

To a solution tert-butyl 4-oxoazepane-1-carboxylate (compound 82.2, 11.0 g, 51.6 mmol) in chloroform (220 mL) at 0° C. was added drop-wise a solution of bromine (3.98 mL, 77.6 mmol) in chloroform (110 mL). The resulting mixture was stirred at room temperature overnight, then the solids that formed were collected by filtration and dissolved in dichloromethane (200 mL). Triethylamine (16.8 mL, 121 mmol) and (Boc)2O (8.70 g, 40.3 mmol) were added to the mixture at 0° C. and the resulting solution was stirred for 3 h at room temperature, and then concentrated under reduced pressure. The crude residue was purified by silica gel chromatography using ethyl acetate/petroleum ether (1:10) as the eluent to give 4.0 g (27%) of the title compound as a yellow oil.

Provenance & Evidence