Reaction #927260

Reaction equation

2-bromo-1,1-dipentyl-cyclopropane

1,1-dipentyl-cyclopropane

potassium t-butoxide

potassium t-butoxide

→

3,3-dipentyl-cyclopropene

Solvents

dimethylsulfoxide

Conditions

Workup

1. 1
   TemperatureThe resulting mixture was heated to 85° C. for 2 hours
2. 2
   Temperaturethen cooled to room temperature
3. 3
   workup.ADDITIONThe reaction mixture was poured onto water
4. 4
   Extractionextracted with diethyl ether
5. 5
   OtherThe resulting mixture was transferred to a separatory funnel
6. 6
   Otherthe phases were separated
7. 7
   DryingThe organic layer was dried over MgSO4
8. 8
   Filtrationfiltered
9. 9
   OtherThe solvent was removed from the filtrate in vacuo

Procedure

To a solution of 1.90 g of an equal mixture of 2-bromo-1,1-dipentyl-cyclopropane and 1,1-dipentyl-cyclopropane in 10 ml dimethylsulfoxide was added 0.818 g (0.00308 mol) of potassium t-butoxide. The resulting mixture was heated to 85° C. for 5 hours and then stirred at room temperature for 16 hours. To this was added 0.100 g of potassium t-butoxide. The resulting mixture was heated to 85° C. for 2 hours then cooled to room temperature. The reaction mixture was poured onto water and then extracted with diethyl ether. The resulting mixture was transferred to a separatory funnel and the phases were separated. The organic layer was dried over MgSO4 and filtered. The solvent was removed from the filtrate in vacuo to yield 1.90 g of 3,3-dipentyl-cyclopropene mixed in equal parts with 1,1-dipentyl-cyclopropane as an oil.

Source