Réaction #312535

Équation de réaction

MeOH

4-bromo-2-(6-carboxyhexyl)cyclopent-2-en-1-one

ethylene glycol

2,6-lutidine

→

4-(2-hydroxyethoxy)-2-(6-carboxyhexyl)cyclopent-2-en-1-one

Solvants

water

Conditions de réaction

Traitement

1. 1
   AutreThe exothermic reaction
2. 2
   Autreto give a temperature of 29° C.
3. 3
   workup.ADDITIONafter 1 minute the mixture is treated during 1 minute with 8.6 g
4. 4
   Filtrationfiltered
5. 5
   workup.ADDITIONThe filtrate is diluted with saturated sodium chloride solution
6. 6
   Extractionextracted with ether
7. 7
   LavageThe extract is washed with half-saturated sodium chloride solution
8. 8
   workup.ADDITIONcontaining a little hydrochloric acid and saturated sodium chloride solution
9. 9
   SéchageThe extract is dried over magnesium sulfate
10. 10
    Concentrationconcentrated
11. 11
    AutreColumn chromatography of the residue on silica gel gives an oil, λmax

Mode opératoire

To a stirred solution of 19.1 g. of crude 4-bromo-2-(6-carboxyhexyl)cyclopent-2-en-1-one (Example 8) in 310 ml. of ethylene glycol is added 15.6 g. (80 mmole) of silver fluoborate during 2 minutes. The exothermic reaction is controlled to give a temperature of 29° C., and after 1 minute the mixture is treated during 1 minute with 8.6 g. (λmmole) of 2,6-lutidine. The mixture is stirred at ambient temperature for 2 hours, diluted with water, and filtered. The filtrate is diluted with saturated sodium chloride solution and extracted with ether. The extract is washed with half-saturated sodium chloride solution containing a little hydrochloric acid and saturated sodium chloride solution. The extract is dried over magnesium sulfate and concentrated. Column chromatography of the residue on silica gel gives an oil, λmax.MeOH =216 mμ(8350); νmax.=3340 (hydroxyl groups), 1700 (carbonyl groups), and 1620 cm-1 (olefin group).

Source