1,3-Dibromo-5,5-dimethylhydantoin → 2-(Bromomethyl)quinoxaline

Participants

Reaction Steps

To a stirring solution of 2-methylquinoxaline (20.0 g, 155 mmol) and benzoyl peroxide (3 g, 12 mmol) in carbon tetrachloride (800 mL) was added 1,3-dibromo-5,5-dimethyl hydantoin (22 g, 77 mmol). The resulting mixture was irradiated with a spotlight (200 watt) for 1.5 hours. The mixture was cooled, filtered, and concentrated to afford crude product which was purified by HPLC (4:1 hexane/EtOAc) to yield 14.0 g (40%) of monobromomethyl product as a grey solid: 1H NMR (CDCl3): δ9.00 (s, 1H, ArH), 8.10 (m, 2H, ArH), 7.80 (m, 2H, ArH), 4.72 (s, 2H, BrCH2 --Ar); and 15.0 g (35%) of dibromomethyl product as a white solid: 1H NMR (CDCl3): δ9.39 (s, 1H, ArH), 8.15 (m, 2H, ArH), 7.90 (m, 2H, ArH), 6.76 (s, 1H, Br2CH--Ar).

Provenance & Evidence