反应详情

温度

10 °C

A five neck five liter round bottom flask equipped with a mechanical stirrer, two condensers, and a dropping funnel was purged with nitrogen then charged under a nitrogen blanket with 1.6 kg (14.5 moles) resorcinol, 160 grams deionized water, and 296.7 grams (1.091 moles) 1,8-dibromooctane. The easily stirable reaction mass was slowly heated to reflux under a slow nitrogen purge. A solution of 181 grams (2.74 moles) 85 percent KOH pellets in 184 grams water was added dropwise at reflux under a nitrogen blanket over a period of two hours. After about 25 percent of the KOH had been added, the reaction mass had dissolved to light tea colored solution then it becomes increasingly clouded as salt was formed. The reaction mixture was refluxed an additional hour after all the KOH had been added. The pH of the reaction mixture was basic. The reaction was quenched with 1.5 liters of water and acidified with 40 percent sulfuric acid. The reaction mixture was then poured into 4 liters of water, cooled in an ice bath to a temperature of 10° C. and filtered to recover a tan colored solid which was slurried in 1.2 liters boiling water to wash out resorcinol and KBr. The cooled slurry was then filtered and 350 grams of crude product was recovered. Crystallization from 400 ml acetone yield 170 grams white crystals, 88 percent pure by HPLC peak area, and recrystallization from 500 ml acetone yields 97.4 grams product of 96 percent purity by HPLC peak area and high purity by gel permeation chromatography (m.p. 78°-82° C.).

1. customA five neck five liter round bottom flask equipped with a mechanical stirrer
2. customtwo condensers, and a dropping funnel was purged with nitrogen
3. temperatureThe easily stirable reaction mass was slowly heated
4. temperatureto reflux under a slow nitrogen
5. custompurge
6. temperatureat reflux under a nitrogen blanket over a period of two hours
7. dissolutionthe reaction mass had dissolved to light tea colored solution
8. temperatureit becomes increasingly clouded as salt
9. customwas formed
10. additionhad been added
11. customThe reaction was quenched with 1.5 liters of water
12. additionThe reaction mixture was then poured into 4 liters of water
13. filtrationfiltered
14. customto recover a tan colored solid which
15. washto wash out resorcinol and KBr
16. filtrationThe cooled slurry was then filtered
17. custom350 grams of crude product was recovered
18. customCrystallization from 400 ml acetone yield 170 grams white crystals, 88 percent
19. custompure by HPLC peak area, and recrystallization from 500 ml acetone