Some common heterocyclic compound, 19056-40-7, name is 4-Bromo-3-methoxyaniline, molecular formula is C7H8BrNO, 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. Quality Control of 4-Bromo-3-methoxyaniline
Step 1: 6-Bromo-7-methoxyquinoline In a 100 mL round-bottom flask, a solution of concentrated sulfuric acid (2.1 mL, 39.6 mmol) in water (2.4 mL) was treated with 3-nitrobenzenesulfonic acid (2.06 g, 10.1 mmol) and glycerol (2.5 mL, 34.8 mmol) to give a thick grey suspension. The mixture was heated to 110 C. (oil bath) and 4-bromo-3-methoxyaniline (1.952 g, 9.66 mmol) was added portion-wise, resulting in an immobile slurry. Additional portions of water (3 mL), glycerol (3 mL), and concentrated sulfuric acid (3 mL) were added and the temperature increased to 140 C. After three hours the mixture had become a homogeneous dark brown solution, and LCMS analysis indicated reaction completion. The solution was cooled to RT, poured onto ice, and the pH was adjusted to 8 by addition of concentrated (30%) aqueous ammonium hydroxide. The mixture was partitioned between ethyl acetate and water, washed with water, brine, dried over magnesium sulfate and concentrated to a brown liquid. Purification by flash column chromatography (24 g silica gel, gradient of 0-20% ethyl acetate in dichloromethane over 25 column volumes) provided 6-bromo-7-methoxyquinoline (1.18 g, 46.2%) as a light brown fluffy solid. 1H NMR (400 MHz, CHLOROFORM-d) ppm 8.86 (dd, J=4.0, 1.5 Hz, 1H), 8.01-8.12 (m, 2H), 7.53 (s, 1H), 7.34 (dd, J=8.1, 4.5 Hz, 1H), 4.07 (s, 3H). NMR indicates the presence of about 10% 7-methyoxyquinoline.
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 19056-40-7, its application will become more common.
Reference:
Patent; NOVARTIS AG; AXFORD, Jake; DALES, Natalie; SUNG, Moo Je; US2014/206661; (2014); A1;,
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