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

Participants

Reaction Steps

To a solution tert-butyl 4-oxoazepane-1-carboxylate (429.2, 11.0 g, 51.6 mmol, 1.00 equiv) in chloroform (220 mL) 0° C. was added dropwise solution of Br2 (12.4 g, 77.6 mmol, 1.50 equiv) in chloroform (110 mL). The resulting mixture was stirred at room temperature overnight. The formed solids were collected by filtration and taken up in 200 mL of dichloromethane. Et3N (12.2 g) and (Boc)2O (8.70 g, 40.3 mmol, 1.00 equiv) were added to the mixture at 0° C. The resulting solution was stirred for 3 h at room temperature, and then concentrated under pressure. The crude residue was purified by silica gel chromatography using ethyl acetate/petroleum ether (1:10) as eluent to give 4.00 g (27%) of the title compound as a yellow oil.

Provenance & Evidence