[Br:1][C:2]1[CH:3]=[C:4]([OH:8])[CH:5]=[CH:6][CH:7]=1.O[CH2:10][CH2:11][N:12]1[C:16](=[O:17])[C:15]2=[CH:18][CH:19]=[CH:20][CH:21]=[C:14]2[C:13]1=[O:22].C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.N(C(OCC)=O)=NC(OCC)=O>C1COCC1>[Br:1][C:2]1[CH:3]=[C:4]([CH:5]=[CH:6][CH:7]=1)[O:8][CH2:10][CH2:11][N:12]1[C:16](=[O:17])[C:15]2=[CH:18][CH:19]=[CH:20][CH:21]=[C:14]2[C:13]1=[O:22]To an ice cold solution of 3-bromophenol (14) (2.0 g, 11.56 mmol), N-(2-hydroxyethyl)phthalimide (2.21 g, 11.6 mmol) and triphenyl phosphine (3.03 g, 11.6 mmol) in anhydrous THF (25 mL) was added diethyl azodicarboxylate (2.57 g, 12.7 mmol) slowly. The reaction mixture was allowed to warm to room temperature and stirred overnight. After concentration under reduced pressure, 50% EtOAc-hexanes (100 mL) was added and the mixture was warmed to 60° C. After cooling to room temperature, the solids were removed by filtration and the filtrate was concentrated under reduced pressure. Purification by flash chromatography (10% EtOAc-hexanes) gave bromide 17 as a white solid. Yield (1.92 g, 48%): 1H NMR (400 MHz, DMSO-d6) δ 7.82-7.88 (m, 4H), 7.19 (t, J=8.4 Hz, 1H), 7.06-7.09 (m, 2H), 6.87-6.90 (m, 1H), 4.22 (t, J=5.6 Hz, 2H), 3.93 (t, J=5.6 Hz, 2H).
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