反应详情

Diethyl oxalate (30 mL) in 20 mL of dry ether was added with stirring to 19 g of potassium ethoxide suspended in 50 mL of dry ether. The mixture was cooled in an ice bath and 20 mL of 3-nitro-o-xylene in 20 mL of dry ether was slowly added. The thick dark red mixture was refluxed for 0.5 hr, concentrated, and treated with 10% sodium hydroxide until almost all of the solid dissolved. Hydrogen peroxide (30%) was then added to the dark red mixture until the red color changed to yellow. The mixture was treated alternately with 10% sodium hydroxide and 30% hydrogen peroxide until the dark red color was no longer present. The solid was filtered off and the filtrate acidified with 6 N hydrochloric acid. The resulting precipitate was collected by vacuum filtration, washed with water, and dried under vacuum to give 9.8 g (45% yield) of 1-methyl-6-nitrophenylacetic acid as an off-white solid. The solid was hydrogenated in methanol over 10% palladium on carbon to give 9.04 g of 4-methyl-2-oxindole as a white solid.

1. temperatureThe mixture was cooled in an ice bath
2. temperatureThe thick dark red mixture was refluxed for 0.5 hr
3. concentrationconcentrated
4. additiontreated with 10% sodium hydroxide until almost all of the solid
5. dissolutiondissolved
6. additionHydrogen peroxide (30%) was then added to the dark red mixture until the red color
7. additionThe mixture was treated alternately with 10% sodium hydroxide and 30% hydrogen peroxide until the dark red color
8. filtrationThe solid was filtered off
9. filtrationThe resulting precipitate was collected by vacuum filtration
10. washwashed with water
11. customdried under vacuum