2-Bromo-1-(2-methoxyphenyl)ethanone

White to greyish-green crystalline powder

Copper (II) bromide (2.97 g, 6.66 mmol) was placed in a twonecked round-bottomed flask fitted with a reflux condenser. EtOAc (10.0 mL) was added to it and the mixture was stirred at 70C for 5 min under nitrogen atmosphere. 1-(2-Methoxyphenyl)ethanone (6) (0.50 g, 3.33 mmol) in CHCl3 (10.0 mL) was slowly added to it and then the mixture was refluxed for 8 h. After completion of the reaction, it was cooled to room temperature, filtered through Celite® pad, and washed with EtOAc (20 mL). The filtrate was concentrated under reduced pressure. The crude was puri- fied by column chromatography (EtOAc:hexane = 1:4) to afford the pure product 7a (0.73 g, 96percent) as brown liquid. Rf = 0.43 (EtOAc/hexane = 1/4); 1 H NMR (300 MHz, CDCl3): δ 7.81 (1H, dd, J = 7.8, 1.8 Hz), 7.52 (1H, td, J = 7.8, 1.8 Hz), 7.05–6.96 (2H, m), 4.61 (2H, s), 3.94 (3H, s); 13C NMR (75 MHz, CDCl3): δ 192.3, 158.8, 134.9, 131.6, 124.9, 121.2, 111.7, 56.0, 38.0.General procedure: The round-bottom flask containing acetophenone derivative 1, 10 (4 mmol) and PTSA (0.076 g, 0.4 mmol) was heated to 60 °C to turn the reaction mixture into a paste and NBS (0.854 g, 4.8 mmol) thenadded slowly. After 15 min, the reaction mixture was cooled to room temperature and water (20 mL)added. The crude product was extracted with dichloromethane (2 x 20 mL), dried over anhydrousNa2SO4 and purified by crystallization from n-hexane–dichloromethane to give pure product. 2-Methoxyphenacyl bromide (2): Yellow solid, soluble in acetone, dichloromethane, chloroform, insolublein water; yield 83percent; m.p.: 43–45 °C; 1H-NMR (500 MHz, CDCl3) (δ, ppm): 7.78 (dd, 1H, J = 1.5, 7.5 Hz, Ar–H), 7.51–7.47 (m, 1H, Ar–H), 7.02–6.96 (m, 2H, Ar–H), 4.57 (s, 2H, CH2), 3.93 (s, 3H, OCH3).This result showed consistency with the data in literature [26].1 -(2-methoxyphenyl)ethan-1 -one 2-bromo-1 - MW: 150.17 (2-methoxyphenyl)ethan-1-one MW: 229.07 [00242] l-(2-methoxyphenyl)ethanone, 1.1, (300 g, 1.0 eq) was added to a reactor containing acetonitrile (1.2 L, 4.0 V). Br2 (319.62 g, 1.0 eq) was added by cooling the reaction to below 25°C. The reaction mixture was stirred for 4 h at 20-25 °C and sampled for IPC until the content of l-(2-methoxyphenyl)ethanone was 6.5percent. NaHSCb (600 ml, 2V) was added to quench the reaction and then stirred for an additional 0.5h at 20-25°C. Product was extracted with methyl tert-butyl ether (600 ml, 2V), three times, to yield a black oil (418 g, crude), which was purified using a column to yield 330 g of 2-bromo-l-(2-methoxyphenyl)ethan-l-one, 1.2, as an off-white solid (98percent purity).To a stirred solution of 2-methoxyacetophenone (10 g, 67 mmol) in diethyl ether (100 mL) was added dropwise bromine (10.6 g, 3.4 mL, 67 mmol) while the temperature was kept below 30 °C. The mixture was stirred at room temperature for 30 min, and then was evaporated to dryness to give the product, which was purified by distillation at 170 °C to give the product (4.77 g, 31percent) as colourless crystals; mp41–44 °C (lit., 34 40–44 °C); 1H NMR δ 7.84–7.81 (m, 1H, H-6), 7.55–7.49 (m, 1H, H-4), 7.06–6.98 (m, 2H, H-3 and 5), 4.61 (s, 2H, CH2Br), 3.95 (s, 3H, OMe).

Molecular Weight:229.07
XLogP3:2.6
Hydrogen Bond Acceptor Count:2
Rotatable Bond Count:3
Exact Mass:227.97859
Monoisotopic Mass:227.97859
Topological Polar Surface Area:26.3
Heavy Atom Count:12
Complexity:159
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes