Réaction #312533

Équation de réaction

methanol

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

2,6-lutidine

MeOH

→

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

Conditions de réaction

Traitement

1. 1
   workup.ADDITIONthe mixture is treated with 2.66 g
2. 2
   workup.STIRRINGis stirred at ambient temperature for 45 minutes
3. 3
   AutreSilver bromide is removed by filtration
4. 4
   Concentrationthe filtrate is concentrated to a volume of 40 ml
5. 5
   workup.ADDITIONThe solution is treated with saturated sodium chloride solution
6. 6
   Extractionextracted with ether
7. 7
   LavageThe extract is washed successively with 0.5 N hydrochloric acid solution, water, and saturated sodium chloride solution
8. 8
   Séchagedried over magnesium sulfate
9. 9
   Concentrationand concentrated
10. 10
    AutrePartition chromatography of the residue on Celite
11. 11
    Autregives an oil, λmax

Mode opératoire

To a stirred solution of 5.30 g. of crude 4-bromo-2-(6-carboxyhexyl)cyclopent-2-en-1-one (Example 8) in 85ml. of methanol at 0°-3° C. is added 4.40 g. (22.6 mmole) of silver fluoborate in one portion. After 2 minutes, the mixture is treated with 2.66 g. (24.8 l mmoles) of 2,6-lutidine. After stirring for 30 minutes at 0°-3° C. the mixture is stirred at ambient temperature for 45 minutes. Silver bromide is removed by filtration, and the filtrate is concentrated to a volume of 40 ml. The solution is treated with saturated sodium chloride solution and extracted with ether. The extract is washed successively with 0.5 N hydrochloric acid solution, water, and saturated sodium chloride solution; dried over magnesium sulfate; and concentrated. Partition chromatography of the residue on Celite gives an oil, λmax.MeOH =220 mμ (7450); νmax.=1715 (carbonyl groups) and 1095 cm-1 (methoxy group).

Source