Reaction #502076

Reaction equation

3,7-dimethyloct-6-en-3-ol

Sodium hydride

allyl bromide

→

6-(allyloxy)-2,6-dimethyloct-2-ene

Solvents

dimethylformamide

Conditions

Workup

1. 1
   Otherfitted with thermocouple, condenser and addition funnel
2. 2
   OtherTo the stirred reaction mixture
3. 3
   Temperaturecooled to ice bath temperature
4. 4
   Temperaturewhilst maintaining
5. 5
   Temperaturecooling
6. 6
   workup.ADDITIONwas added to the reaction mixture
7. 7
   Extractionextracted with methyltert-butyl ether (3×30 mL)
8. 8
   WashThe combined organic phase was washed with dilute hydrochloric acid (100 mL), saturated brine (100 mL)
9. 9
   Dryingdried with magnesium sulphate
10. 10
    OtherThe solvent was removed in vacuo
11. 11
    workup.DISTILLATIONthe residue fractionally distilled

Procedure

Sodium hydride (60% dispersion in mineral oil, 6.8 g, 170 mmol) and dimethylformamide (100 mL) were added to a three necked 500 mL flask fitted with thermocouple, condenser and addition funnel. To the stirred reaction mixture was added dropwise 3,7-dimethyloct-6-en-3-ol (22 g, 139 mmol) at room temperature. The mixture was stirred for 1 hr, cooled to ice bath temperature then allyl bromide (97% pure by GC RPA, 19 g, 15 mmol) was added dropwise whilst maintaining cooling. After a further 3 hr stirring ice/water was added to the reaction mixture and then extracted with methyltert-butyl ether (3×30 mL). The combined organic phase was washed with dilute hydrochloric acid (100 mL), saturated brine (100 mL) and dried with magnesium sulphate. The solvent was removed in vacuo and the residue fractionally distilled to give 6-(allyloxy)-2,6-dimethyloct-2-ene (25.4 g, 92% pure by GC RPA, 118 mmol, chemical yield 70%).

Source