Reaction #54455

Reaction equation

2,2,6-trimethylcyclohexanone

3-hydroxy-3,7-dimethyl-nona-4,6,8-trien-1-yne

ammonium chloride

ethyl bromide

magnesium

→

7-hydroxy-3,7-dimethyl-9-(1-hydroxy-2,2,6-trimethylcyclohexyl)-nona-1,3,5-trien-8-yne

Solvents

benzene

benzene

diethyl ether

ether

Conditions

Workup

1. 1
   Temperaturethe mixture was heated
2. 2
   Temperatureto reflux for 30 minutes
3. 3
   Temperaturethe mixture refluxed 30 minutes
4. 4
   Temperaturethe mixture refluxed for 15 minutes
5. 5
   WashThe organic phase was washed with brine
6. 6
   Otherdried
7. 7
   Concentrationconcentrated

Procedure

A solution of ethyl bromide (1.75 g.) in diethyl ether was added to a suspension of magnesium (0.385 g.) in ether and the mixture was heated to reflux for 30 minutes. A solution of the alcohol, 3-hydroxy-3,7-dimethyl-nona-4,6,8-trien-1-yne, (1.0 g.) in dry benzene was added and the mixture refluxed 30 minutes. A solution of 2,2,6-trimethylcyclohexanone (1.12 g.) in benzene was added and the mixture refluxed for 15 minutes and poured into saturated aqueous ammonium chloride solution. The organic phase was washed with brine dried and concentrated to give 7-hydroxy-3,7-dimethyl-9-(1-hydroxy-2,2,6-trimethylcyclohexyl)-nona-1,3,5-trien-8-yne which was chromatographed on activity III alumina to give pure 7-hydroxy-3,7-dimethyl-9-(1-hydroxy-2,2,6-trimethyl-cyclohexyl)-nona-1,3,5-trien-8-yne.

Source