反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.
实验步骤: In a dried 3 neck flask fitted with magnetic stirrer and condensor was placed metal magnesium (12 mmol) and ether (1.8 mL) Neat bromoethane (2.5 mmol) was added via syringe and the reaction was started immediately. A solution of bromoethane (10.5 mmol) in toluene (30 mL) was added to the solution slowly. After completion of the addition, the solution was stirred at room temperature for 30 min under nitrogen before adding neat diethylamine (24 mmol). The solution was further stirred at room temperature for 15 min. The solution was cooled to 0° C. and a mixture of 1-(pyridin-2-yl)ethanone (XVIII) (12 mmol) and 2-bromoisobutyrophenone (XVII) (13 mmol) was added to the solution. The solution was further stirred for 3 h at 0° C. under nitrogen. Aqueous 5% H2SO4 (20 mL) was added to the solution and the solution was warmed to room temperature. The organic layer was separated, dried over MgSO4 and filtered. The organic layer was then treated with Et3N (10 mmol) and allowed to stir overnight at room temperature. The solution was then washed with water, dried over MgSO4, filtered and concentrated. The residue was purified by flash chromatography eluting with 1-5% EtOAc in hexane gradient to give 2,2-dimethyl-1-phenyl-4-(pyridin-2-yl)butane-1,4-dione 9 as a colorless viscous oil (11% yield). 1H NMR (CDCl3, 400 MHz): δ ppm 1.47 (s, 6H), 3.80 (s, 2H), 7.34-7.50 (m, 4H), 7.65-7.75 (m, 2H), 7.80 (m, 1H), 7.94 (m, 1H), 8.67 (m, 1H); ESIMS found C17H17NO2 m/z 268 (M+H).
In a dried 3 neck flask
fitted with magnetic stirrer
was added via syringe
After completion of the addition
The solution was further stirred at room temperature for 15 min
The solution was cooled to 0° C.
was added to the solution
The solution was further stirred for 3 h at 0° C. under nitrogen
the solution was warmed to room temperature
The organic layer was separated
dried over MgSO4
filtered
to stir overnight at room temperature
The solution was then washed with water
dried over MgSO4
filtered
concentrated
The residue was purified by flash chromatography
eluting with 1-5% EtOAc in hexane gradient
来源 ID: ord-64ff65fb7eef4f38acd97f6027a742c3