Sodium borohydride → (1S,3R)-3-{[tert-Butyl(dimethyl)silyl]oxy}cyclopentan-1-ol
Reaction equation
[Si:1]([O:8][C@@H:9]1[CH2:13][C@H:12]([OH:14])[CH:11]=[CH:10]1)([C:4]([CH3:7])([CH3:6])[CH3:5])([CH3:3])[CH3:2].[BH4-].[Na+]>C(O)C.[Ni]>[Si:1]([O:8][C@@H:9]1[CH2:10][CH2:11][C@H:12]([OH:14])[CH2:13]1)([C:4]([CH3:7])([CH3:6])[CH3:5])([CH3:3])[CH3:2]Participants
Conditions
- Temperature
- 0 °C
Procedure
Dissolve (-)-cis-4-tert-butyldimethylsilyloxy-2-cyclopentenol (28.85 g, 135 mmol, prepared in example 10) in ethanol (75 mL) and treated with Raney nickel (1.85 g, 32 mmol, previously washed with water (2×50 mL) and ethanol (2×50 mL)). Charge the atmosphere with hydrogen at 50 psi (344.74 kPa) and shake the mixture. After 5.25 hours, filter the reaction. Cool the filtrate to 0° C. and treat with sodium borohydride (0.54 g, 14.3 mmol). After stirring for 2 hours, concentrate the solution under vacuum and distill the resulting oil by Kugelrohr distillation (40°-60° C., 1 mmHg) to provide the title compound (25.5 g, 87%) as a colorless oil, [α]20D =-3.9°, (c=0.99, chloroform); 1H NMR (CDCl3) δ 4.4 (m, 1 H), 4.3 (m, 1 H), 3.03 (d, 1 H, J=10.5 Hz), 1.9-1.6 (m, 6 H), 0.89 (s, 9 H), 0.07 (s, 6 H); 13C NMR (CDCl3) δ 74.9, 74.1, 44.4, 34.2, 34.1, 25.8, 17.9, -4.9, -5.0; IR (neat) νmax 3405, 2957, 2932, 2888, 2858, 1256, 1091, 1069, 1038, 1026 cm-1 ; CIMS m/e (% relative intensity) 217 (M+H+, 81), 199 (M+H+ --H2O, 37), 67 (100). This (-)-enantiomer (title compound) could not be separated from the (+)-enantiomer (antipode) using the previously described chiral column.
Workup
- washpreviously washed with water (2×50 mL) and ethanol (2×50 mL))
- additionCharge the atmosphere with hydrogen at 50 psi (344.74 kPa) and shake the mixture
- filtrationfilter
- customthe reaction
- concentrationconcentrate the solution under vacuum
- distillationdistill the resulting oil
- distillationby Kugelrohr distillation (40°-60° C., 1 mmHg)
Sources & evidence
- ORD record
- ord-1ef092946cb242e6a02560b44ec7f33f
- Source dataset
- uspto-grants-1998_09
- Patent number
- US05808112
Reaction notes
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