反应详情

To a solution of 493 mg of potassium tert-butoxide in 5 mL of dimethylformamide (anhydrous) is added dropwise a solution of 556 mg of ethyl pyrrole-2-carboxylate (prepared as described in Organic Synthesis, Vol. 51, p. 100) in 5 mL of anhydrous dimethylformamide. On completion of the addition the mixture is allowed to stir at room temperature for 1 hour. To this mixture is added a solution of 1 g of 4-chloro-2-nitrobenzyl bromide in 5 mL of dimethylformamide. The reaction mixture is then heated to 75° and maintained at this temperature for 18 hours, then allowed to cool to room temperature. The reaction mixture is poured into 20 mL of ice-water and extracted with 2×30 mL of ether. The combined ethereal extracts are washed with 2×30 mL of water followed by 30 mL of saturated sodium bicarbonate solution. The ethereal extracts are dried over anhydrous sodium sulfate and the solvent evaporated under reduced pressure to yield ethyl 1-(4-chloro-2-nitrobenzyl)-pyrrole-2-carboxylate melting at 104°-106°.

1. additionOn completion of the addition the mixture
2. temperatureThe reaction mixture is then heated to 75°
3. temperaturemaintained at this temperature for 18 hours
4. temperatureto cool to room temperature
5. extractionextracted with 2×30 mL of ether
6. washThe combined ethereal extracts are washed with 2×30 mL of water
7. dry with materialThe ethereal extracts are dried over anhydrous sodium sulfate
8. customthe solvent evaporated under reduced pressure