[CH3:1][C:2]1[CH:3]=[C:4]([C:18]([O:20][CH3:21])=[O:19])[C:5]([C:8]2[CH:13]=[CH:12][CH:11]=[C:10]([C:14]([O:16][CH3:17])=[O:15])[CH:9]=2)=[CH:6][CH:7]=1.C1C(=O)N([Br:29])C(=O)C1>C(Cl)(Cl)(Cl)Cl.C(OOC(=O)C1C=CC=CC=1)(=O)C1C=CC=CC=1>[Br:29][CH2:1][C:2]1[CH:3]=[C:4]([C:18]([O:20][CH3:21])=[O:19])[C:5]([C:8]2[CH:13]=[CH:12][CH:11]=[C:10]([C:14]([O:16][CH3:17])=[O:15])[CH:9]=2)=[CH:6][CH:7]=1To a solution of 4-methyl-[1,1′-biphenyl]-2,3′-dicarboxylic acid, dimethyl ester (2.26 g, 7.9 mmol) in CCl4 (50 mL) were added benzoyl peroxide (0.010 g, 0.04 mmol) and NBS (1.42 g, 8.0 mmol), and the mixture was refluxed for 3 days. The reaction mixture was allowed to cool to room temperature, filtered, and concentrated. The residue was purified by column chromatography (95:5 to 90:10 hexanes/EtOAc) to afford 4-bromomethyl-[1,1′-biphenyl]-2,3′-dicarboxylic acid, dimethyl ester (1.71 g, 60%): 1H NMR (DMSO-d6) δ 3.61(s, 3H), 3.88 (s, 3H), 4.84 (s, 2H), 7.48-7.50 (d, J=8.0 Hz, 1H), 7.59-7.60 (m, 2H), 7.72-7.75 (m, 1H), 7.85 (s, 1H), 7.90 (m, 1H), 7.97-7.99 (m, 1H).
Wird geladen…
