n-Butyl lithium → 4-Methylene-1-phenylpiperidine

Participants

Reaction Conditions

Reaction Steps

In a 50 mL round bottom flask, methyltriphenylphosphonium iodide (1.384 g, 3.42 mmol) was suspended in THF (10.0 mL) and cooled to 0° C. N-Butyllithium (1.370 mL, 3.42 mmol) was added drop-wise and the resulting yellow suspension was stirred at 0° C. for 30 min. A solution of 1-phenylpiperidin-4-one (0.500 g, 2.85 mmol) in THF (5.0 mL) was added drop-wise and the orange, yellow suspension was then allowed to slowly warm to 23° C. over 2 hr. The reaction mixture was quenched with sat. NH4Cl (30 mL), the aq. layer was extracted with EtOAc (2×50 mL) and the combined organic extracts were washed with brine (30 mL), dried over MgSO4, filtered, and concentrated in vacuo. The crude yellow oil was purified by flash chromatography (EtOAc:Hex, 1:9 isocratic) affording the title compound as a clear, light yellow oil (0.0906 g, 18.33% yield). 1H NMR (400 MHz, DMSO-d6) δ ppm 2.14-2.39 (m, 4H) 3.12-3.29 (m, 4 H) 4.74 (s, 2H) 6.64-6.85 (m, 1H) 6.87-7.07 (m, 2H) 7.08-7.29 (m, 2H). ESI-MS: m/z 174.1 (M+H)+.

Provenance & Evidence