Bromine → 5-Bromo-2,3-dihydro-5h-benzo[b]oxepin-4-one

Participants

Reaction Steps

To a solution of 2,3-dihydro-5H-benzo[b]oxepin-4-one (1 eq, 1.6 mmol, 260 mg), in anhydrous diethyl ether (10 ml), bromine was added dropwise (1.1 eq, 1.76 mmol, 90 ul), and the reaction allowed to stir for an hour. The reaction was absorbed onto silica and purified on the ISCO companion running a gradient from 0% ethyl acetate/petrol to 15% ethyl acetate/petrol, with the product seen at 9% ethyl acetate. This gave 5-bromo-2,3-dihydro-5H-benzo[b]oxepin-4-one as an oil (270 mg, yield 70%).

Provenance & Evidence