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

Participants

Reaction Conditions

Reaction Steps

Aluminum chloride (5 g, 37.5 mmol) was added portionwise into N-(4-bromophenyl)-3-methylbut-2-enoic amide (Intermediate 3, 7.69 g, 30.0 mmol) in a 500 mL beaker at 130° C. over 1 h. The beaker was then cooled to 80° C. and another portion of aluminum chloride (1 g, 7.5 mmol) was added. After stirring at 80° C. for 0.5 h, the beaker was cooled with an ice-bath and ice was added slowly into the mixture. The resulting slurry was then extracted with ether (3×10 mL). The combined organic layer was washed with brine (1×10 mL), saturated NaHCO3 (1×10 mL), dried (MgSO4) and concentrated at reduced pressure. Purification by flash chomatography (75:25 hexane/ethyl acetate) yielded the title compound as a pale yellow solid (5.20 g, 68% yield).

Provenance & Evidence