2-Butenamide, N-(4-bromophenyl)-3-methyl- → 6-bromo-4,4-dimethyl-3,4-dihydroquinolin-2(1H)-one

Participants

Reaction Conditions

Reaction Steps

To 6.7 g (26.02 mmol) of molten N-(4-bromophenyl)3,3-dimethylacrylamide (Compound 92) (heated to 135 degrees C.) was added 4.15 g (31.09) of aluminum chloride over 25 min. The reaction mixture was stirred at 130 degrees C. for 16 h and then treated with a further 1 g (7.5 mmol) of aluminum chloride. The reaction mixture was heated at 130 degrees C for a further 9 h and then cooled to room temperature: The reaction was then quenched by the slow addition of 100 ml of ice cold water with slight warming of flask to facilitate mixing. The mixture was extracted with 1×100 ml and 4×50 ml of ether. The organic extracts were combined and washed with 25 ml of saturated NaCl solution and then dried (MgSO4). The solvent was removed in vacuo and the residue purified by flash chromatography (silica; 30% ethyl acetate in hexanes) to give the title compound as a pale yellow solid. PMR (CDCl3): δ 1.37 (6H, s), 2.53 (2H, s), 6.85 (1H, d, J~8.4 Hz), 7.32 (1H, dd, J~8.4 Hz, 2.1 Hz), 7.43 (1H, d, J~2.81 Hz), 10.12 (1H, broad s).

Provenance & Evidence