Reaction #95306

Reaction equation

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

acetic acid

→

4-acetoxy-2-(6-carbethoxyhexyl)cyclopent-2-en-1-one

Solvents

MeOH

Conditions

Workup

1. 1
   workup.ADDITIONA mixture of 51.6 g
2. 2
   Temperatureat reflux for 4.5 hours
3. 3
   TemperatureThe mixture is cooled
4. 4
   Othersolids are removed by filtration
5. 5
   ConcentrationThe filtrate is concentrated
6. 6
   Extractionextracted with hot hexane
7. 7
   WashThe extract is washed with saturated sodium bicarbonate solution and saturated sodium chloride solution
8. 8
   Dryingdried over mangesium sulfate
9. 9
   Concentrationconcentrated
10. 10
    Otherto give an oil
11. 11
    workup.DISTILLATIONThe crude product is distilled at reduced pressure
12. 12
    Otherto give a liquid, b.p. 152°-163° C. (0.01 mm)

Procedure

A mixture of 51.6 g. (0.137 moles) of crude 4-bromo-2-(6-carbethoxyhexyl)cyclopent-2-en-1-one (Example 1274), 27 g. (0.162 moles) of silver acetate, and 200 ml. of glacial acetic acid is stirred at reflux for 4.5 hours. The mixture is cooled, and solids are removed by filtration. The filtrate is concentrated and extracted with hot hexane. The extract is washed with saturated sodium bicarbonate solution and saturated sodium chloride solution, dried over mangesium sulfate, and concentrated to give an oil. The crude product is distilled at reduced pressure to give a liquid, b.p. 152°-163° C. (0.01 mm); λmax.MeOH =223 mμ (10700); νmax.=1745 (ester carbonyl groups), 1725 (ketone carbonyl groups), and 1235 cm-1 (acetoxy group).

Source