583-75-5, These common heterocyclic compound, 583-75-5, name is 4-Bromo-2-methylaniline, 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.
3,6-Dibromotoluene In a 2000 ml beaker containing 400 ml of 23percent aqueous HBr, 46.5 g (0.25 mol) of melted 2-methyl-4-bromoaniline was slowly added. This mixture was stirred for 20 minutes using a mechanical stirrer, then cooled to -5¡ã C. Then a solution of 22.4 g (0.33 mol) of NaNO2 in 130 ml of water was added dropwise over 1 hour at this temperature. The diazonium reagent obtained was added in several portions to a solution of 35.9 g (0.25 mmol) of CuBr in 100 ml of 47percent HBr at 0¡ã C. The resulting mixture was warmed to 70¡ã C., stirred for 30 minutes at this temperature, and, then, cooled to room temperature. The product was extracted with 3*200 ml of methyl-tert-butyl ether. The combined extract was dried over K2CO3 and evaporated to dryness. Firstly, the crude product was purified using short column with Silica Gel 60 (40-63 mum, d 60 mm, 140 mm; eluant: hexanes). Fractional distillation gave colorless oil, b.p. 100-102¡ã C./10 mm Hg. Yield, 36.1 g (58percent). Anal. calc. for C7H6Br2: C, 33.64; H, 2.42. Found: C, 33.79; H, 2.50. 1H NMR (300 MHz, CDCl3): delta 7.39 (m, 1H, 5-H), 7.37 (m, 1H, 3-H), 7.18 (m, 1H, 6-H), 2.38 (s, 3H, Me). 13C NMR (75 MHz, CDCl3): delta 139.9, 133.6, 133.5, 130.3, 123.5, 120.9, 22.7.
Chemical properties determine the actual use. Each compound has specific chemical properties and uses. We look forward to more synthetic routes in the future to expand reaction routes of 583-75-5.
Reference:
Patent; Voskoboynikov, Alexander Z.; Izmer, Vyatcheslav V.; Asachenko, Andrey F.; Nikulin, Mikhail V.; Ryabov, Alexey N.; Lebedev, Artyom Y.; Coker, Catalina L.; Canich, Jo Ann M.; US2007/135597; (2007); A1;,
Bromide – Wikipedia,
bromide – Wiktionary