Ethyl Acetate → tert-Butyl 3-oxocycloheptylcarbamate

Beteiligte Stoffe

Reaktionsschritte

To a stirring mixture of cyclohept-2-enone (26.96 g, 245.0 mmol) and tert-butyl carbamate (28.7 g, 245 mmol) in DCM (245 mL) was added bismuth nitrate pentahydrate (22.79 g, 47.0 mmol). The resulting mixture was stirred at room temperature overnight. The reaction was diluted reaction with ethyl acetate (500 mL) and water (300 mL) and the biphasic mixture was filtered through a bed of Celite. The bed of Celite was washed well with ethyl acetate and water, and layers of the filtrate separated. The organic layer was concentrated to an oil that was purified by silica gel chromatography (0-40% ethyl acetate in hexanes). Product containing fractions were concentrated to afford the title compound (31.09 g, 137 mmol, 55.9% yield). 1H NMR (400 MHz, DMSO-d6) δ ppm 6.92 (d, J=7.03 Hz, 1H), 3.60 (d, J=8.59 Hz, 1H), 2.55-2.69 (m, 1H), 2.26-2.45 (m, 2H), 1.69-1.93 (m, 3H), 1.44-1.61 (m, 2H), 1.37 (d, J=5.08 Hz, 11H). MS (ESI) m/z 228.5 [M+H]+.

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