N-bromobutanimide → 2-Bromo-5-methoxybenzyl bromide

To a stirred solution of 4-bromo-3-methylanisole (100 g, 497 mmol) in dry dichloromethane (500 mL) was added N-bromosuccinimide (97 g, 545 mmol) followed by benzoyl peroxide (6 g, 25 mmol). The reaction was gently refluxed with a 150 watt flood lamp with reflector placed approximately 12 inches from the reaction flask. After 24 h the reaction was concentrated by rotary evaporation to half its volume and allowed to sit for 4 h. The white precipitate which formed was filtered off and rinsed with a small volume of dichloromethane. The filtrate was concentrated to dryness and the remaining solid was triturated with hexanes and filtered. Drying under vacuum gave the title compound (100.25 g, 72%) as white needles: GC tR=6.56 min (HP 530 μm×20 m methylsilicone column, He carrier flow 20 mL/min, 100° C. initial temp., 1 min initial time, 10° C./min rate, 200° C. final temp., 1 min final time); 1H NMR (400 MHz, CDCl3) δ 7.44 (d, J=10 Hz, 1 H), 6.99 (d, J=3 Hz, 1 H), 6.73 (dd, 1H), 4.55 (s, 2H), 3.80 (s, 3H).

1. temperatureThe reaction was gently refluxed with a 150 watt flood lamp with reflector
2. concentrationAfter 24 h the reaction was concentrated by rotary evaporation to half its volume
3. customThe white precipitate which formed
4. filtrationwas filtered off
5. washrinsed with a small volume of dichloromethane
6. concentrationThe filtrate was concentrated to dryness
7. customthe remaining solid was triturated with hexanes
8. filtrationfiltered
9. customDrying under vacuum

ORD record

ord-f26263dd50fe4a40b17362d6036ce305

Source dataset

uspto-grants-2004_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06825188B2