CC1(C)CCCC(C)(C)N1.[Li]CCCC.[C:16]([Si:20]([CH3:23])([CH3:22])Cl)([CH3:19])([CH3:18])[CH3:17].[C:24]([O:27][CH2:28][CH3:29])(=[O:26])[CH3:25]>C1COCC1>[C:16]([Si:20]([O:26][C:24]([O:27][CH2:28][CH3:29])=[CH2:25])([CH3:23])[CH3:22])([CH3:19])([CH3:18])[CH3:17]To a solution of 2,2,6,6-tetramethylpiperidine (17.34 mL, 102.14 mmol) in THF (63.4 mL) under argon, 2.9 M BuLi in hexanes (34.05 mL, 98.74 mmol) was added dropwise at 0° C. The reaction was stirred for 15 min. and subsequently cooled to −78° C. t-Butyldimethylchlorosilane (TBDMSCl) (16.94 g, 112.36 mmol) in THF (25.4 mL) was added and then a solution of anhydrous ethyl acetate (8.38 mL, 85.12 mmol) in THF (57.2 mL) was slowly added over 1 h. The mixture was stirred for an additional 10 min at −78° C. and then stirred at r.t. for 1 h. The solution was then diluted with hexanes (285.9 mL), filtered through a Celite pad, and the filtrate concentrated. Distillation under vacuum at 42-50° C. gave an orange oil (g, 2.0%). 1H NMR (400 MHz, CDCl3) δ 3.74 (q, 2H, J=7.0 Hz, CH2), 3.22 (d, 1H, J=2.0 Hz, CH2), 3.05 (d, 1H, J=2.0 Hz, CH2), 1.29 (t, 3H, J=7.1 Hz, CH3), 0.94 (s, 9H, CH3), 0.17 (s, 6H, CH3); 13C NMR (400 MHz, CDCl3) δ 160.3, 62.4, 59.6, 24.79, 17.3, 13.5, −5.4
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