[CH3:1][Si]([N-][Si](C)(C)C)(C)C.[Na+].[CH:11]([C@H:13]1[CH2:18][CH2:17][CH2:16][CH2:15][N:14]1[C:19]([O:21][C:22]([CH3:25])([CH3:24])[CH3:23])=[O:20])=O>[Br-].C[P+](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1.C1COCC1>[CH:11]([C@H:13]1[CH2:18][CH2:17][CH2:16][CH2:15][N:14]1[C:19]([O:21][C:22]([CH3:25])([CH3:24])[CH3:23])=[O:20])=[CH2:1]NaHMDS (1.0 M in THF, 18.6 mL, 18.6 mmol) was slowly added over 15 min to a 0° C. solution of methyltriphenylphosphonium bromide (7.19 gm, 20.1 mmol) in THF (65 mL). The yellow mixture was stirred at 0° C. for 45 min and then cooled to −78° C. A solution of (R)-tert-butyl 2-formylpiperidine-1-carboxylate (3.30 gm, 15.5 mmol) in THF (10 mL) was added dropwise. The reaction mixture was then stirred at 0° C. for 1 hr. The reaction was quenched by the addition of saturated aqueous NH4Cl. The solution was partitioned between EtOAc and water. The aqueous phase was isolated and extracted with EtOAc. All organic phases were combined, dried over MgSO4, filtered and concentrated. The crude product was purified using silica gel chromatography (ISCO system) eluting with a gradient of 0-100% EtOAc/Hex to give (R)-tert-butyl 2-vinylpiperidine-1-carboxylate (2.53 gm, 12.0 mmol, 77% yield) as an orange oil. Anal. Calcd. for C12H21N0 m/z 211.3. found: 212.0 (M+H)+.
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