Reaction #927253

Reaction equation

1-(7-carboxyheptyl)-cyclopropene

Triethylamine

methylchloroformate

→

7-cycloprop-1-enyl-heptanoic acid ethyl ester

Yield 75.0%

Solvents

ether

Conditions

Workup

1. 1
   Otherthe reaction mixture was transferred to a separatory funnel
2. 2
   WashThe ether phase was washed with water (2×) and brine
3. 3
   Dryingdried over magnesium sulfate
4. 4
   Filtrationfiltered
5. 5
   workup.DISSOLUTIONThe product was dissolved in ethanol
6. 6
   Temperaturecooled in an ice bath
7. 7
   workup.ADDITIONtreated with 1 ml of a 21% sodium ethoxide in ethanol solution
8. 8
   workup.ADDITIONwater and ether were added
9. 9
   WashThe ether phase was washed with 1N sodium hydroxide solution, water, and brine
10. 10
    Dryingdried over magnesium sulfate
11. 11
    Filtrationfiltered

Procedure

A solution of 220 mg (1.3 mmol) of 1-(7-carboxyheptyl)-cyclopropene in ether was cooled to 0° C. Triethylamine (0.20 g, 2 mmol) was added, then 0.12 g (1.3 mmol) of methylchloroformate was added. After 2 hours at 0° C., the reaction mixture was transferred to a separatory funnel. The ether phase was washed with water (2×) and brine, dried over magnesium sulfate, filtered and stripped. The product was dissolved in ethanol, cooled in an ice bath and treated with 1 ml of a 21% sodium ethoxide in ethanol solution. The reaction mixture was stirred ½ hour, then water and ether were added. The ether phase was washed with 1N sodium hydroxide solution, water, and brine, dried over magnesium sulfate, filtered and stripped to give 10 mg of 75% pure 7-cycloprop-1-enyl-heptanoic acid ethyl ester.

Source