Hydrochloric Acid → (2-Acetamidophenyl) cyclohexyl methanone

Participants

Reaction Conditions

Reaction Steps

Cyclohexylmagnesium bromide (240 ml of a 2M solution in ether (200 ml ) was added dropwise to a solution of 2-methyl-4H-3,1-benzoxazin-4-one (100 g) in ether (1100 ml) at -10° C. over 2 h. The mixture was stirred at this temperature for 2 h, then at ambient temperature for 30 min. After cooling to -10° C. the suspension was treated with 2M HCl (600 ml), keeping the temperature below 0° C. After stirring for 15 min the layers were separated, and the ethereal layer washed sequentially with water (500 ml), 5% sodium hydroxide solution (2×500 ml) and finally water (2×500 ml). The organic layer was separated, dried (MgSO4), evaporated in vacuo and chromatographed on silica using petrol:ethyl acetate (2:1) to give (2-acetamidophenyl) cyclohexyl methanone (28 g) as a solid, mp 66° C.; δH (CDCl3, 360 MHz) 1.25-1.89 (10H, m), 2.23 (3H, s), 3.33 (1H, m), 7.13 (1H, dt, J=6 and 1 Hz), 7.53 (1H, dt, J=6 and 1 Hz), 7.92 (1H, d, J=6 Hz), 8.76 (1H, d, J=6 Hz), 11.73 (1H, br s).

Provenance & Evidence