反应详情

Sodium hydride in oil (60%, 24 g, 0.6 mole) was washed portionwise with petroleum spirit (60°-80°; dried over CaH2 ; 250 ml) in an atmosphere of nitrogen. The sodium hydride was then covered with toluene (Na dried; 150 ml) and the mixture heated to vigorous reflux while being stirred mechanically. A solution of the diester (11) (30 mmoles) in toluene (Na dried, 60 ml), containing superdry ethanol (10 drops) was added during 6 min and reflux continued for a further 54 min. After cooling the mixture in ice, the excess sodium hydride was decomposed by the slow addition of glacial acetic acid (45 ml) followed by water (100 ml). The aqueous layer was removed, the toluene layer washed with water (50 ml) and the combined aqueous layers were extracted with toluene (25 ml). The combined toluene layers were then extracted with a freshly prepared solution of sodium bicarbonate (24 g) in water (360 ml). Extraction was repeated twice more with sodium bicarbonate (12 g) in water (180ml). Filtration, followed by acidification with concentrated hydrochloric acid, of the bicarbonate extracts yielded 2.01 g (26.6%) of crude (12). Crystallisation from hexane (charcoal) gave a cream product m.p. 90.5°-93.5°.

1. temperaturethe mixture heated
2. temperatureto vigorous reflux
3. additionwas added during 6 min
4. temperaturereflux
5. temperatureAfter cooling the mixture in ice
6. customThe aqueous layer was removed
7. washthe toluene layer washed with water (50 ml)
8. extractionthe combined aqueous layers were extracted with toluene (25 ml)
9. extractionThe combined toluene layers were then extracted with a freshly prepared solution of sodium bicarbonate (24 g) in water (360 ml)
10. extractionExtraction
11. filtrationFiltration