N-bromobutanimide → Tert-butyl 2-bromo-4,5-dihydropyrido[4,3-b]thieno[2,3-d]oxepin-8-yl(tert-butyl)carbamate

Participants

Reaction Steps

A solution of N-bromosuccinimide (59 mg, 0.33 mmol) in 1 ml of dimethylformamide was added dropwise to a solution of tert-butyl tert-butyl(4,5-dihydropyrido[4,3-b]thieno[2,3-d]oxepin-8-yl)carbamate (120 mg, 0.32 mmol) in 2 ml of dimethylformamide (DMF). The reaction mixture was stirred for 18 hours, concentrated in vacuum and partitioned between water and ethyl acetate. The organic layer was washed with water, brine, dried over sodium sulfate and concentrated in vacuum to give tert-butyl 2-bromo-4,5-dihydropyrido[4,3-b]thieno[2,3-d]oxepin-8-yl(tert-butyl)carbamate which was used in the next step without further purification. MS: (ESI+) 453.2

Provenance & Evidence