[O:1]=[C:2]1[C:6]2([CH2:11][CH2:10][N:9]([C:12]([O:14][CH2:15][C:16]3[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=3)=[O:13])[CH2:8][CH2:7]2)[CH:5]([C:22]2[CH:27]=[CH:26][CH:25]=[CH:24][CH:23]=2)[CH2:4][NH:3]1.C[Si]([N-][Si](C)(C)C)(C)C.[Li+].O1CCCC1.Br[CH2:44][C:45]1[CH:46]=[C:47]([CH:52]=[CH:53][CH:54]=1)[C:48]([O:50][CH3:51])=[O:49]>CN(C)C=O.C(OCC)(=O)C>[CH3:51][O:50][C:48]([C:47]1[CH:46]=[C:45]([CH:54]=[CH:53][CH:52]=1)[CH2:44][N:3]1[CH2:4][CH:5]([C:22]2[CH:27]=[CH:26][CH:25]=[CH:24][CH:23]=2)[C:6]2([CH2:11][CH2:10][N:9]([C:12]([O:14][CH2:15][C:16]3[CH:17]=[CH:18][CH:19]=[CH:20][CH:21]=3)=[O:13])[CH2:8][CH2:7]2)[C:2]1=[O:1])=[O:49]A mixture of benzyl 1-oxo-4-phenyl-2,8-diazaspiro[4.5]decane-8-carboxylate (1 g, 3.03 mmol, 1 equiv), lithium bis(trimethylsilyl)amide, 1M in tetrahydrofuran (3.33 ml, 3.33 mmol, 1.1 equiv), and methyl 3-(bromomethyl)benzoate (694.08 g, 3.03 mmol, 1 equiv) in N,N-dimethylformamide was stirred for 16 h at ambient temperature. Reaction was diluted with ethyl acetate and the organic layer was washed with water and brine. The combined organic layers were dried over MgSO4 and concentrated in vacuo. The crude residue was purified using the Biotage flash chromatography system (SNAP 100 g cartridge, Rf=0.6, gradient—10%-50% ethyl acetate in hexanes) to afford the title compound as a cream solid (1.34 g, 92%); 1H NMR (400 MHz, DMSO-d6): δ 0.87-0.92 (m, 1H); 1.33 (s, 9H); 1.46-1.51 (m, 2H); 1.54-1.65 (m, 1H); 3.03-3.07 (m, 1H); 3.34-3.40 (m, 3H); 3.46-3.48 (m, 1H); 3.57-3.61 (m, 1H); 3.69-3.71 (m, 1H); 3.86 (s, 3H); 4.56 (s, 2H); 7.14-7.16 (m, 2H); 7.20-7.28 (m, 3H); 7.52-7.59 (m, 2H); 7.89-7.91 (m, 2H); MS for C31H32N2O5 m/z 513.23 (M+H)+.
Wird geladen…