[CH3:1][O:2][C:3](=[O:17])[C:4]1[CH:9]=[CH:8][C:7]([CH3:10])=[CH:6][C:5]=1[C:11]1[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=1.[Br:18]N1C(=O)CCC1=O.C(OCC)(=O)C>C(Cl)(Cl)(Cl)Cl.N(C(C)(C)C#N)=NC(C)(C)C#N>[CH3:1][O:2][C:3](=[O:17])[C:4]1[CH:9]=[CH:8][C:7]([CH2:10][Br:18])=[CH:6][C:5]=1[C:11]1[CH:12]=[CH:13][CH:14]=[CH:15][CH:16]=1A mixture of 4-methyl-2-phenylbenzoic acid methyl ester (2.26 g, 10 mmol), prepared as in Example 227B, N-bromosuccinimide (1.87 g, 10.5 mmol) and 2,2′-azobisisobutyronitrile (25 mg) in carbon tetrachloride (40 mL) was stirred at reflux for 7 hours. The reaction mixture was poured into ethyl acetate and extracted with water (2×), aqueous sodium hydrogen sulfite and brine, dried, filtered, and concentrated in vacuo. Chromatography on silica gel (10% ethyl acetate-hexane) gave 4-bromomethyl-2-phenylbenzoic acid methyl ester (2.57 g, 84%).
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