These common heterocyclic compound, 28342-75-8, name is 1,5-Dibromo-2,4-difluorobenzene, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route. Product Details of 28342-75-8
38. Preparation of 1-bromo-2,4-difluoro-5-methoxybenzene; To a solution of 1,3 dibromo-4,6-difluorobenzene (10.0 g, 37 mmol) in THF (50 mL) at -20° C. was added isopropyl magnesium chloride (2.0M in THF, 42 mmol) and the resulting solution warm to 0° C. and stirred for 30 minutes. Trimethylborate (4.7 g, 45 mmol) was added and the mixture stirred at ambient temperature for 1 hour. The solution was recooled to -20° C. and peracetic acid (32percent, 50 mmol) was added and the solution was stirred for 30 minutes at ambient temperature. The solution was then quenched with sodium bisulfite (5percent solution, 75 mL) and then acidified with 6 N hydrochloric acid and extracted with ethyl ether (2.x.75 mL). Combined extracts were dried (sodium sulfate) and concentrated. The crude phenol was dissolved in acetonitrile (40 mL) and potassium carbonate (10 g, 74 mmol) and iodomethane (5.7 g, 40 mmol) were added and stirred at ambient temperature for 20 hours. The solution was concentrated and the residue taken into water (50 mL) and extracted with ethyl ether (2.x.75 mL) and the combined extracts were washed with brine, dried (sodium sulfate), and concentrated. The residue was purified by chromatography (hexanes) to give 1-bromo-2,4-difluoro-5-methoxybenzene (2.0 g, 8.6 mmol): LC/MS (m/z=223).
The synthetic route of 1,5-Dibromo-2,4-difluorobenzene has been constantly updated, and we look forward to future research findings.
Reference:
Patent; Balko, Terry W.; Schmitzer, Paul R.; Daeuble, John F.; Yerkes, Carla N.; Siddall, Thomas L.; US2007/179060; (2007); A1;,
Bromide – Wikipedia,
bromide – Wiktionary