2,3-Dichloro-5,6-dicyano-1,4-benzoquinone → 7-bromobenzo[b]oxepin-5(2H)-one

Participants

Reaction Steps

2,4,6-Collidine (5.6 ml), DDQ (9.0 g, 40 mmol) and (7-bromo-2,3-dihydrobenzo[b]oxepin-5-yloxy)(tert-butyl)dimethylsilane was dissolved in toluene, the mixture was stirred for 5.5 hours at room temperature. the mixture was concentrated in vacuo and then purified by column chromatography to give 7-bromobenzo[b]oxepin-5(2H)-one (4.5 g, 94%). 1H-NMR (MeOD): 4.71 (m, 2H), 6.38 (m, 1H), 6.76 (m, 1H), 6.99 (m, 1H), 7.54 (m, 1H), 8.06 (m, 1H).

Provenance & Evidence