Potassium bis(trimethylsilyl)amide → Methyl 4-vinylbicyclo[2.2.2]octane-1-carboxylate

Participants

Reaction Steps

To a stirred solution of methyltriphenylphosphonium bromide (9.1 g, 12.8 mmol) in THF (50 ml) at 0° C. was added potassium hexamethyldisilazide (0.5M in toluene, 48.6 ml), dropwise over 5 min. The resulting mixture was allowed to warm up to room temperature over 1 h, then cooled again to 0° C. and treated with methyl 4-formylbicyclo[2.2.2]octane-1-carboxylate (4-1) (Chapman, N. B. et al. J. Org. Chem., 1970, 35, 917) (2.5 g, 12.8 mmol). The reaction mixture was stirred at room temperature for 18 h then diluted with EtOAc (350 ml). The organic phase was washed with aqueous HCl (1 N), saturated aqueous sodium bicarbonate, and brine, then dried (Na2SO4) and concentrated in vacuo. The resulting solid was purified by flash silica gel chromatography, eluting with a gradient 0-4% EtOAc/hexanes. The resulting methyl 4-vinylbicyclo[2.2.2]octane-1-carboxylate (4-2) was isolated as a clear, colorless oil.

Provenance & Evidence