N-bromobutanimide → 5-Bromo-1-(1,4-dioxaspiro[4.5]decan-8-yl)indoline
Reaction equation
[O:1]1[C:5]2([CH2:10][CH2:9][CH:8]([N:11]3[C:19]4[C:14](=[CH:15][CH:16]=[CH:17][CH:18]=4)[CH2:13][CH2:12]3)[CH2:7][CH2:6]2)[O:4][CH2:3][CH2:2]1.[Br:20]N1C(=O)CCC1=O>CN(C=O)C.O>[Br:20][C:16]1[CH:15]=[C:14]2[C:19](=[CH:18][CH:17]=1)[N:11]([CH:8]1[CH2:9][CH2:10][C:5]3([O:4][CH2:3][CH2:2][O:1]3)[CH2:6][CH2:7]1)[CH2:12][CH2:13]2Participants
Procedure
A solution of compound 3 (3.45 g, 13.30 mmol) in dry DMF (30 mL) was treated with N-bromosuccinimide (2.36 g, 13.30 mmol) in DMF (20 mL) at 0° C. over a period of 30 min. The reaction was stirred at same temperature for 3.5 h. The reaction was diluted with water (200 mL) and product was extracted into ethyl acetate (3×25 mL). The combined ethyl acetate layer was washed with water (2×50 mL), brine (25 mL) and dried (Na2SO4). The solvent was evaporated and the crude product was purified by column chromatography on silica gel (ethyl acetate:hexanes, 1:4) to obtain compound 4 (4.05 g, 90%) as a syrup. 1H NMR (CDCl3) δ 7.12-7.10 (m, 2H), 6.25 (d, J=9.0 Hz, 1H), 3.95 (s, 4H), 3.38 (t, J=16.8 Hz, 3H), 2.91 (t, J=16.8 Hz, 2H), 1.86-1.57 (m, 8H). MS-ESI (m/z, %): 340 (98), 338 (M+, 100), 198 (18).
Workup
- extractionwas extracted into ethyl acetate (3×25 mL)
- washThe combined ethyl acetate layer was washed with water (2×50 mL), brine (25 mL)
- dry with materialdried (Na2SO4)
- customThe solvent was evaporated
- customthe crude product was purified by column chromatography on silica gel (ethyl acetate:hexanes, 1:4)
Sources & evidence
- ORD record
- ord-38096bdf6fef4785bc0177548e524f53
- Source dataset
- uspto-grants-2012_05
- Patent number
- US08173813B2
Reaction notes
Loading…