[OH:1][C@H:2]1[CH2:6][C:5](=[O:7])[CH:4]=[CH:3]1.CN(CC)C.[Si:13](Cl)([C:16]([CH3:19])([CH3:18])[CH3:17])([CH3:15])[CH3:14].C(OCC)(=O)C>C(Cl)Cl>[CH3:17][C:16]([Si:13]([CH3:15])([CH3:14])[O:7][C@H:5]1[CH2:6][C:2](=[O:1])[CH:3]=[CH:4]1)([CH3:19])[CH3:18]To a 1-L round bottomed flask was charged (4S)-4-Hydroxy-2-cyclopenten-1-one (32) (20 g, 204 mmol, prepared described in Khanapure, S.; Najafi, N.; Manna, S.; Yang, J.; Rokash. J. J. Org. Chem., 1995, 60, 7448) in DCM (200 mL) followed by N,N-dimethylethylamine (47.7 g, 653 mmol), tert-butyldimethylsilyl chloride (46.1 g, 306 mmol) and a catalytic amount of 4-N,N-dimethylaminopyridine (1 g). The mixture was stirred at room temperature for 24 hours. The reaction mixture was poured into ethyl acetate (200 mL) and the organic layer washed with water (200 mL), aqueous HCl (1 N, 2×100 mL), brine (100 mL) and saturated sodium bicarbonate solution (100 mL). The organic layer was dried over magnesium sulfate and concentrated in vacuo to afford the title compound as a crude product (42 g, ˜98% yield).
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