[CH:1]1([OH:7])[CH2:5][CH2:4][CH:3]([OH:6])[CH2:2]1.N1C=CN=C1.[Si:13](Cl)([C:16]([CH3:19])([CH3:18])[CH3:17])([CH3:15])[CH3:14]>O1CCCC1>[C:16]([Si:13]([CH3:15])([CH3:14])[O:6][C@H:3]1[CH2:4][CH2:5][C@H:1]([OH:7])[CH2:2]1)([CH3:19])([CH3:18])[CH3:17].[C:16]([Si:13]([CH3:15])([CH3:14])[O:6][C@@H:3]1[CH2:4][CH2:5][C@H:1]([OH:7])[CH2:2]1)([CH3:19])([CH3:18])[CH3:17]To a mixture of 1,3-cyclopentanediol (5.0 g, 48.9 mmol) (cis/trans mixture, Aldrich) and imidazole (3.3 g, 48.5 mmol) in tetrahydrofuran (100 mL) at 0° C. was added tert-butyldimethylsilyl chloride (5.2 g, 34.3 mmol) (Aldrich) in portions (250 mg every 15 minutes). When all additions were completed the reaction mixture was allowed to slowly warn to room temperature. After stirring overnight the mixture was partitioned between ethyl acetate and water. The organic layer was collected, dried over sodium sulfate, filtered and concentrated. The residue was purified by chromatography on a silica gel column with a 0–20% ethyl acetate in hexanes gradient to give (±)-trans-3-(tert-butyl-dimethyl-silanyloxy)-cyclopentanol as a colorless viscous oil, (Yield 4.23 g, 57%), and (±)-cis-3-(tert-butyl-dimethyl-silanyloxy)-cyclopentanol (Yield 420 mg, 6%).
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