반응 #684944

반응 방정식

2,5-Dibromohydroquinone

sodium hydroxide

dodecylbromide

→

2,5-Dibromo-4-dodecyloxy phenol

수율 60.0%

용매

ethanol

반응 조건

후처리

1. 1
   온도the reaction mixture was cooled
2. 2
   기타the precipitate formed
3. 3
   여과was filtered
4. 4
   세척washed with methanol
5. 5
   기타The filtrate was evaporated
6. 6
   기타to remove the solvent
7. 7
   workup.ADDITION2 L of distilled water was added to the residue
8. 8
   workup.WAITboiled gently for 1 h
9. 9
   온도cooled
10. 10
    여과The resulting precipitate was collected by filtration
11. 11
    세척washed with water
12. 12
    기타dried in vacuo
13. 13
    기타The crude product was purified by column chromatography
14. 14
    workup.ADDITIONa mixture of solvents (CH2Cl2:hexanes, 4:6)
15. 15
    기타to get the pure product in 60% yield

실험 절차

2,5-Dibromohydroquinone 3 (40.2 g, 0.15 mol) was dissolved in a solution of sodium hydroxide (9.2 g, 0.23 mol) in 1.5 L of absolute ethanol at room temperature under nitrogen atmosphere. The reaction mixture was warmed to 50-60° C. with constant stirring. The dodecylbromide (36 ml, 0.15 mol) was added drop wise to the above reaction mixture at 60° C. After 10 h of stirring under nitrogen atmosphere, the reaction mixture was cooled and the precipitate formed was filtered and washed with methanol. This precipitate was identified as dialleylated-2,5-dibromohydroquinone as a side product. The filtrate was evaporated to remove the solvent. 2 L of distilled water was added to the residue and the mixture was acidified with 36% HCl, boiled gently for 1 h and cooled. The resulting precipitate was collected by filtration, washed with water and dried in vacuo. The crude product was purified by column chromatography using a mixture of solvents (CH2Cl2:hexanes, 4:6) to get the pure product in 60% yield.

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