[Br:1][C:2]1[CH:3]=[N:4][CH:5]=[C:6]([CH:10]=1)C(O)=O.C1(P(N=[N+]=[N-])(C2C=CC=CC=2)=[O:18])C=CC=CC=1.CC[N:30]([CH2:33]C)CC.[CH2:35]([OH:42])[C:36]1[CH:41]=[CH:40][CH:39]=[CH:38][CH:37]=1>C1(C)C=CC=CC=1>[Br:1][C:2]1[CH:10]=[C:6]([NH:30][C:33](=[O:18])[O:42][CH2:35][C:36]2[CH:41]=[CH:40][CH:39]=[CH:38][CH:37]=2)[CH:5]=[N:4][CH:3]=1To a suspension of 5-bromonicotinic acid (20.0 g, 99.0 mmol) in toluene (200 mL) was added diphenylphosphoryl azide (25.6 mL, 118.8 mmol) and Et3N (16.6 mL, 118.8 mmol). After stirring at room temperature for 30 min, benzyl alcohol (15.4 mL, 148.5 mmol) was added. The mixture was stirred at room temperature for 1 h then refluxed overnight. After cooling to room temperature, the reaction mixture was washed with H2O, saturated aqueous NaHCO3 and brine, dried over MgSO4 and concentrated. Purification by flash chromatography (15-50% EtOAc in Hexane) provided 22.2 g (72.5 mmol, 73% yield) of benzyl 5-bromo-3-pyridinylcarbamate: 1H NMR (CDCl3) δ 8.39-8.32 (m, 2 H), 8.29 (s, 1 H), 7.45-7.32 (m, 5 H), 6.94 (s, 1 H), 5.22 (s, 2 H); ESMS m/e: 307.0 (M+H)+.
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