Methyl iodide → 1-Benzyl-3,3-dimethylpiperidin-4-one

Participants

Reaction Conditions

Reaction Steps

1-Benzylpiperid-4-one (9.45 g, 8.92 mL, 49.98 mmol, 1.0 eq) was added to a suspension of sodium hydride (3.50 g of a 60% suspension in oil, 87.50 mmol, 1.75 eq) in tetrahydrofuran (100 mL). Iodomethane (9.84 g, 3.93 mL, 62.96 mmol, 1.26 eq) was added and the reaction heated to 60° C. for 5 hours. The reaction was filtered and the filtrate concentrated. The residue was partitioned between EtOAc (150 mL) and water (150 mL). The aqueous phase was extracted with EtOAc (150 mL). The organics were combined, washed with brine (150 mL), dried (Na2SO4), and concentrated under reduced pressure. Column chromatography (silica, 20→60% EtOAc-hexane) yielded the title compound as a colourless oil; 1H nmr (CDCl3) δ 7.36-7.26 (5H, m, C6H5), 3.56 (2H, s, CH2C6H5), 2.72 (2H, t, J 6.0 Hz, pipH-5 or H-6), 2.51 (2H, t, J 6.0 Hz, pipH-5 or H-6), 2.41 (2H, s, pipH-2), 1.13 (6H, s, 2×CH3); and 1-benzyl-3-methylpiperidin-4-one (3.12 g) as a colourless oil.

Provenance & Evidence