反应详情

2-Methylindanone (0.112 mole), cyanacetic acid (10.5 g., 0.123 mole), acetic acid (6.6 g.), and ammonium acetate (1.7 g.) in dry toluene (15.5 ml.) was refluxed with stirring for 21 hrs., as the liberated water was collected in a Dean Stark trap. The toluene was concentrated and the residue dissolved in 60 ml. of hot ethanol and 14 ml. of 2.2 N aqueous potassium hydroxide solution. 22 g. Of 85% KOH in 150 ml. of water was added and the mixture refluxed for 13 hr. under N2. The ethanol was removed under vacuum, 500 ml. water added, the aqueous solution washed well with ether and then boiled with charcoal. The aqueous filtrate was acidified to pH 2 with 50% hydrochloric acid, cooled and the precipitate of 2-methylinden-3-acetic acid was collected.

1. custom, as the liberated water was collected in a Dean Stark trap
2. concentrationThe toluene was concentrated
3. dissolutionthe residue dissolved in 60 ml
4. additionof water was added
5. temperaturethe mixture refluxed for 13 hr
6. customThe ethanol was removed under vacuum, 500 ml
7. additionwater added
8. washthe aqueous solution washed well with ether
9. temperaturecooled
10. customthe precipitate of 2-methylinden-3-acetic acid was collected