Diethyl Ether → 7-Bromo-4-(chloromethyl)-5-methyl-2,3-dihydrobenzo[b]oxepine

Participants

Reaction Steps

To a solution of (7-bromo-5-methyl-2,3-dihydrobenzo[b]oxepin-4-yl)methanol from step H6 (1.53 g, 5.68 mmol) in dichloromethane (10 mL) was added DIPEA (2.98 mL, 17.1 mmol) followed by methanesulfonyl chloride (0.886 mL, 11.4 mmol) at 0° C. The mixture was allowed to gradually warm up to rt. After 18 h at rt, diethyl ether (50 mL) was added, the mixture was washed with water, and the organic layer was separated, dried over sodium sulfate, filtered, and concentrated in vacuo to give 7-bromo-4-(chloromethyl)-5-methyl-2,3-dihydrobenzo[b]oxepine (2.05 g, 7.13 mmol, 125% yield). The crude material was used in the next step without further purification. 1H NMR (500 MHz, chloroform-d) δ 7.40 (d, J=2.4 Hz, 1H), 7.36-7.32 (m, 1H), 6.96 (s, 1H), 4.56 (t, J=6.3 Hz, 2H), 4.37 (s, 2H), 2.34 (t, J=1.0 Hz, 2H), 2.17 (s, 3H).

Provenance & Evidence