N-bromobutanimide → Methyl 2-(bromomethyl)-3-nitrobenzoate

Beteiligte Stoffe

Reaktionsschritte

A stirred mixture of methyl 2-methyl-3-nitrobenzoate(17.6 g, 87.1 mmol) and N-bromosuccinimide (18.9 g, 105 mmol) in carbon tetrachloride (243 mL) was heated under gentle reflux with a 100 W light bulb situated 2 cm away shining on the reaction mixture overnight. After 18 hours, the reaction mixture was cooled to room temperature and filtered. The filtrate was washed with water (2×120 mL), brine(120 mL), and dried (MgSO4). The solvent was removed in vacuo to give a yellow solid. The product was purified by flash chromatography (hexane:ethyl acetate 8:2) to give 22 g (93%) of methyl 2-bromomethyl-3-nitrobenzoate as a yellow solid: mp 69-72° C.; 1H NMR (CDCl3) δ 8.13-8.09 (dd, J=1.36 and 7.86 Hz, 1H), 7.98-7.93 (dd, J=1.32 and 8.13 Hz, 1H), 7.57-7.51 (t, J=7.97Hz, 1H), 5.16 (s, 2H), 4.0 (s, 3H); 13C NMR (CDCl3) δ 65.84, 150.56, 134.68, 132.64, 132.36, 129.09, 53.05, 22.70; HPLC: Waters Nova-Pak C18 column, 4 micron, 1 mL/min, 240 nm, 40/60 CH3CN/0.1%H3PO4(aq), 8.2 min 99%. Anal. Calcd for C9H8NO4Br: C, 39.44; H, 2.94; N, 5.11, Br, 29.15. Found: C, 39.51; H, 2.79; N, 5.02; Br, 29.32.

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