N-bromobutanimide → HCID 25136453, compound
Reaction equation
[CH3:1][O:2][C:3](=[O:27])[C@H:4]([NH:16][C:17]([O:19][CH2:20][C:21]1[CH:26]=[CH:25][CH:24]=[CH:23][CH:22]=1)=[O:18])[CH2:5][C:6]1[CH:15]=[CH:14][C:9]2[NH:10][C:11](=[O:13])[O:12][C:8]=2[CH:7]=1.[Br:28]N1C(=O)CCC1=O>C(Cl)Cl>[CH3:1][O:2][C:3](=[O:27])[C@H:4]([NH:16][C:17]([O:19][CH2:20][C:21]1[CH:22]=[CH:23][CH:24]=[CH:25][CH:26]=1)=[O:18])[CH2:5][C:6]1[CH:15]=[C:14]([Br:28])[C:9]2[NH:10][C:11](=[O:13])[O:12][C:8]=2[CH:7]=1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
A mixture of (R)-2-benzyloxycarbonylamino-3-(2-oxo-2,3-dihydro-benzooxazol-6-yl)-propionic acid methyl ester (418 mg, 1.13 mmol), N-bromosuccinimide (221 mg, 1.24 mmol), silica gel (EM Scientific, 230-400 mesh, 2.51 g) and methylene chloride (70 mL) was stirred at room temperature for 16 h. Solvents were removed in vacuo and the residue was subjected to silica gel chromatography using ethyl acetate/hexanes (2:3) as eluent to afford the title compound. 1H-NMR (CD3COCD3, 500 MHz) δ 10.71 (s, 1H), 7.35-7.28 (m, 6H), 7.21 (s, 1H), 6.75 (d, J=7.5 Hz, 1H), 5.06 (d, 12.5 Hz, 1H), 5.02 (d, J=12.5 Hz, 1H), 4.56-4.51 (m, 1H), 3.73 (s, 3H), 3.26 (dd, J=14.0, 5.0 Hz, 1H), 3.03 (dd, J=14.0, 10.0 Hz, 1H); 13C-NMR (CD3COCD3, 125 MHz) δ 172.2, 156.4, 153.8, 144.4, 137.6, 133.7, 129.8, 128.7, 128.2, 128.0, 127.8, 110.1, 100.9, 66.3, 55.9, 52.0, 37.3; Mass spec. 448.03 (MH+).