反应详情

温度

80 °C

The following reagents were placed in a flask equipped with a magnetic stirrer, oil bath and reflux condenser protected with a guard tube containing anhydrous calcium sulfate ("Drierite"): p-(1,1-dimethyl-2-hydroxyethyl)benzoic acid, 20 g, 0.103 mole; sodium bicarbonate, 9.4 g, 0.112 mole; N,N-dimethylacetamide, 100 mL; and methyl iodide, 28.4 g, 0.2 mole. The mixture was heated at 80° C. for 2.5 hours, cooled to room temperature and filtered to remove any unreacted hydroxyacid. The clear solution was then poured into 600 mL water and stirred for 10 minutes. 50 mL of 5% aqueous sodium bicarbonate was added and the resultant solution extracted 3 times with 120 mL portions of ether. The ether layers were combined, washed with dilute aqueous bicarbonate, dilute aqueous sodium thiosulfate and finally water, and dried over anhydrous potassium carbonate. The ether solution was evaporated to give a colorless liquid which crystallized upon standing at room temperature. Yield 99%. The compound was purified by distillation, bp 135°- 140° C. at 0.3 to 0.5 mm Hg, (0.04 to 0.667 kPa) followed by recrystallization from ether/pentane (1/4 vol.) at -20° C., mp 44°-45° C. Elemental analysis, IR and NMR spectra were all consistent with the proposed structure.

1. customThe following reagents were placed in a flask
2. customequipped with a magnetic stirrer, oil bath
3. temperaturereflux condenser
4. customprotected with a guard tube
5. temperaturecooled to room temperature
6. filtrationfiltered
7. customto remove any unreacted hydroxyacid
8. additionThe clear solution was then poured into 600 mL water
9. addition50 mL of 5% aqueous sodium bicarbonate was added
10. extractionthe resultant solution extracted 3 times with 120 mL portions of ether
11. washwashed with dilute aqueous bicarbonate, dilute aqueous sodium thiosulfate and finally water
12. dry with materialdried over anhydrous potassium carbonate
13. customThe ether solution was evaporated
14. customto give a colorless liquid which
15. customcrystallized
16. customupon standing at room temperature
17. distillationThe compound was purified by distillation, bp 135°- 140° C. at 0.3 to 0.5 mm Hg, (0.04 to 0.667 kPa)
18. customfollowed by recrystallization from ether/pentane (1/4 vol.) at -20° C.