Reaction #927251

Reaction equation

1,1,2-Tribromo-2-(7-carboxyheptyl)-cyclopropane

ether

Methyllithium

Water

→

7-cycloprop-1-enyl-heptanoic acid

Conditions

Workup

1. 1
   workup.WAITThe reaction mixture was put in an ice bath for 5 minutes
2. 2
   Otherrecooled to −78° C. until workup
3. 3
   Temperaturewas warmed to room temperature
4. 4
   OtherThe aqueous phase was separated
5. 5
   Extractionthe ether phase was extracted with three times with 1N NaOH solution
6. 6
   Extractionextracted with ether three times
7. 7
   WashThe ether extracts were washed with brine
8. 8
   Dryingdried over magnesium sulfate

Procedure

1,1,2-Tribromo-2-(7-carboxyheptyl)-cyclopropane (1.28 g, 3.1 mmol) was dissolved in 60 ml of ether and cooled to −78° C. Methyllithium (9.0 ml, 12.6 mmol) was added and the reaction was stirred at −78° C. for two hours. The reaction mixture was put in an ice bath for 5 minutes, then recooled to −78° C. until workup. Water was added to the reaction mixture, which was warmed to room temperature. The aqueous phase was separated, and the ether phase was extracted with three times with 1N NaOH solution. The combined aqueous extracts were acidified with aqueous HCl, and extracted with ether three times. The ether extracts were washed with brine, dried over magnesium sulfate and stripped to give 300 mg of 7-cycloprop-1-enyl-heptanoic acid.

Source