Hexane → cis-4-bromo-1-tert-butoxycarbonyl-(2S)-(tert-butyldiphenylsilyloxy)methylpyrrolidine
Reaction equation
[C:1]([O:5][C:6]([N:8]1[CH2:12][C@H:11](O)[CH2:10][C@H:9]1[CH2:14][O:15][Si:16]([C:29]([CH3:32])([CH3:31])[CH3:30])([C:23]1[CH:28]=[CH:27][CH:26]=[CH:25][CH:24]=1)[C:17]1[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=1)=[O:7])([CH3:4])([CH3:3])[CH3:2].C1C=CC(P(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1.C(Br)(Br)(Br)[Br:53].CCCCCC>C1COCC1>[Br:53][C@@H:11]1[CH2:12][N:8]([C:6]([O:5][C:1]([CH3:4])([CH3:3])[CH3:2])=[O:7])[C@H:9]([CH2:14][O:15][Si:16]([C:29]([CH3:32])([CH3:31])[CH3:30])([C:23]2[CH:28]=[CH:27][CH:26]=[CH:25][CH:24]=2)[C:17]2[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=2)[CH2:10]1Participants
Procedure
To a stirred solution of trans-1-tert-butoxycarbonyl-(2S)-(tert-butyldiphenylsilyloxy) methyl-4-hydroxypyrrolidine (910 mg, 2.0 mmol) and Ph3P (628 mg, 2.4 mmol) in THF (20 ml) was added CBr4 (993 mg, 3.0 mmol) at room temperature. The reaction mixture was stirred at room temperature for 0.5 hr. n-Hexane (40 ml) was added thereto. The resulting solid was filtered off, and dried in vacuo. The residue was purified by column chromatography on silica gel with n-hexane to n-hexane-EtOAc (3:2, v/v) as eluent to give cis-4-bromo-1-tert-butoxycarbonyl-(2S)-(tert-butyldiphenylsilyloxy) methylpyrrolidine (1.0 g, quant.) as a pale yellow oil. 1H-NMR (CDCl3) δ1.06 (s, 9H), 1.31 and 1.45 (each s, 9H), 2.63 (m, 2H), 3.49 (m, 1H), 3.89-4.14 (m, 5H), 7.35-7.42 (m, 6H), 7.64-7.66 (,4Hm).
Workup
- filtrationThe resulting solid was filtered off
- customdried in vacuo
- customThe residue was purified by column chromatography on silica gel with n-hexane to n-hexane-EtOAc (3:2
Sources & evidence
- ORD record
- ord-72b0116519ac4c46bdf4484bcb3b3885
- Source dataset
- uspto-grants-2004_06
- Patent number
- US06756378B2
Reaction notes
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