9-Benzyloxy-4,4,6,8-tetramethyl-5-oxo-7-(2,2,2-trichloroethoxycarbonyloxy)-3-(triethylsilanyloxy)-nonanoic Acid Tert-Butyl Ester → 9-Benzyloxy-3-(diethylmethylsilanyloxy)-7-hydroxy-4,4,6,8-tetramethyl-5-oxo-nonanoic Acid Tert-Butyl Ester

HRID 131618Notes

Reaction equation

HRID 131618 reaction equation
[C:1]([O:5][C:6](=[O:45])[CH2:7][CH:8]([O:37][Si:38]([CH2:43]C)([CH2:41][CH3:42])[CH2:39][CH3:40])[C:9]([CH3:36])([CH3:35])[C:10](=[O:34])[CH:11]([CH3:33])[CH:12]([O:24]C(OCC(Cl)(Cl)Cl)=O)[CH:13]([CH3:23])[CH2:14][O:15][CH2:16][C:17]1[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=1)([CH3:4])([CH3:3])[CH3:2]>[Zn].C1COCC1.CC(O)=O>[C:1]([O:5][C:6](=[O:45])[CH2:7][CH:8]([O:37][Si:38]([CH2:41][CH3:42])([CH2:39][CH3:40])[CH3:43])[C:9]([CH3:35])([CH3:36])[C:10](=[O:34])[CH:11]([CH3:33])[CH:12]([OH:24])[CH:13]([CH3:23])[CH2:14][O:15][CH2:16][C:17]1[CH:18]=[CH:19][CH:20]=[CH:21][CH:22]=1)([CH3:4])([CH3:2])[CH3:3]

Participants

4

Reactant 1

HCID 668509949-Benzyloxy-4,4,6,8-tetramethyl-5-oxo-7-(2,2,2-trichloroethoxycarbonyloxy)-3-(triethylsilanyloxy)-nonanoic Acid Tert-Butyl Ester

Product 1

HCID 668507919-Benzyloxy-3-(diethylmethylsilanyloxy)-7-hydroxy-4,4,6,8-tetramethyl-5-oxo-nonanoic Acid Tert-Butyl EsterYield 1,022.2%

Reagents, catalysts & solvents 2

HCID 23994ZincCatalyst2×HCID 23444217Acetic acid tetrahydrofuranSolvent

Procedure

To a solution of 71 (22.9 mg, 3.2 μmol) in 1:1 THF/AcOH (1.4 mL) was added Zn (5.0 mg, 7.8 μmol, nanosize). The mixture was sonicated for 15 min. More Zn (5.0 mg, 7.8 μmol, nanosize) was added, followed by sonication for a further 15 min. The suspension was filtered through a celite pad, washing with EtOAc several times. The filtrates were washed with sat. NaHCO3, brine, dried over MgSO4 and concentrated under vacuum. The crude residue was passed through a short plug of silica gel eluting with hexane/EtOAc 4:1 to give 17.1 mg (99% yield) of 71a as colorless oil: 1H NMR (400 MHz, CDCl3) δ (m, 6H), 0.96 (t, J=7.9 Hz, 9H), 0.97 (d, J=6.8 Hz, 3H), 1.05 (d, J=6.8 Hz, 3H), 1.11 (s, 3H), 1.26 (s, 3H), 1.44 (s, 9H), 1.84-1.90 (m, 1H), 2.21 (dd, J=6.7 and 17.0 Hz, 1H), 2.36 (dd, J=6.7 and 17.0 Hz, 1H), 3.24-3.29 (m, 1H), 3.44-3.52 (m, 2H), 3.67 (dd, J=3.9 and 8.9 Hz, 1H), 4.36 (dd, J=3.5 and 6.5 Hz, 1H), 4.50 (d, J=12.0 Hz, 1H), 4.54 (d, J=12.0 Hz, 1H), 7.32-7.36 (m, 5H); 13C NMR (100 MHz, CDCl3) δ 5.0, 6.9, 9.7, 13.9, 20.2, 21.8, 28.0, 36.3, 40.8, 41.5, 53.7, 72.5, 72.9, 73.2, 73.6, 80.7, 127.4, 127.5, 128.2, 138.6, 171.0, 221.4; IR (film, NaCl, cm−1) 3502, 2959, 2875, 1731, 1683, 1456, 1366, 1154, 1098, 996, 739; LRMS (ESI) calcd for C30H52O6SiCl3Na [M+Na+] 559.3, found 559.3; [α]23D=−41.0 (c=0.4, CHCl3).

Workup

  1. customThe mixture was sonicated for 15 min
  2. customfollowed by sonication for a further 15 min
  3. filtrationThe suspension was filtered through a celite pad
  4. washwashing with EtOAc several times
  5. washThe filtrates were washed with sat. NaHCO3, brine
  6. dry with materialdried over MgSO4
  7. concentrationconcentrated under vacuum

Sources & evidence

ORD record
ord-0aa6a44bf4364b819b0f5d408cff9cee
Source dataset
uspto-grants-2008_06
Patent number
US07384964B2

Reaction notes

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