反应详情

To a solution of ethyl ester 3.6 g (20 mmol) of step 2 in dimethylformamide 30 mL was added K2CO3 5.5 g (40 mmol), followed by stirring at room temperature for 10 min. Dibromoethane 1.9 mL (22 mmol) was added dropwise to the reaction mixture which was then stirred for 3 hours under reflux. The reaction mixture was cooled to room temperature, concentrated in a vacuum, diluted with ethylacetate, and washed with a saturated sodium bicarbonate solution and a saturated NaCl solution. The resulting residue was dried over magnesium sulfate and concentrated in a vacuum to afford 3.7 g of the title compound (yield 89%).

1. stirringwas then stirred for 3 hours
2. temperatureunder reflux
3. temperatureThe reaction mixture was cooled to room temperature
4. concentrationconcentrated in a vacuum
5. additiondiluted with ethylacetate
6. washwashed with a saturated sodium bicarbonate solution
7. dry with materialThe resulting residue was dried over magnesium sulfate
8. concentrationconcentrated in a vacuum