[CH:1]([NH:4][CH:5]([CH3:7])[CH3:6])([CH3:3])[CH3:2].[Li:8]CCCC.[N+:13](/[CH:16]=[CH:17]/[C:18]1[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=1)([O-])=O.[CH2:24]1[CH2:28][O:27][CH2:26][CH2:25]1>>[Li+:8].[CH3:2][CH:1]([N-:4][CH:5]([CH3:7])[CH3:6])[CH3:3].[C:18]1([CH:17]2[C:25]3([CH2:24][CH2:28][NH:4][CH2:1][CH2:2]3)[C:26](=[O:27])[NH:13][CH2:16]2)[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=1An LDA (14 mmol) solution was prepared by treating diisopropylamine (1.37 g, 14 mmol) with BuLi (1.6 M, 8.5 mL, 14 mmol) at −78° C. in dry THF (10 mL) under argon and allowing to warm up to −20° C. This solution was then cooled to −60° C. added to a solution of 1-benzyl-piperidine-4-ethyl carboxylate (3.05 g, 12 mmol) in THF (8 mL) at −60° C. and allowed to warm up to −40° C. over 1 h whereupon a solution of trans-beta-nitrostyrene (1.93 g, 13 mmol) in THF (8 mL) was added dropwise. The reaction mixture was allowed to warm up to room temperature over 1 h and then quenched with ammonium chloride (saturated, 40 mL) and the product extracted with ethyl acetate (2×40 mL). The combined organic extracts were then washed with brine, dried over sodium sulfate, filtered and evaporated. Purification by chromatography on silica gel eluting with DCM:MeOH (9:1) afforded the title compound (4.1 g, 84%) as a light yellow gum. MS: m/e=397.4 (M+H).
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