Reaktion #2146731

Reaktionsgleichung

phosphoric acid

1-isobutylcyclohexanol

phosphoric acid

1-isobutylcyclohexanol

→

1-isobutylcyclohex-1-ene

Lösungsmittel

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.DISTILLATIONWhile 1-isobutylcyclohex-1-ene and water distilled (boiling point 60° C.)
2. 2
   workup.ADDITIONAt the end of the addition
3. 3
   Temperaturheated further (vacuum from 170 to 40 mbar)
4. 4
   SonstigeThe distillate was decanted
5. 5
   Extraktionthe water phase extracted with pentane (100 ml)
6. 6
   Trocknenphases were dried (MgSO4)
7. 7
   Sonstigethe solvent evaporated

Vorschrift

In a flask equipped with a Vigreux-distillation apparatus, crude 1-isobutylcyclohexanol (200 g, 1.28 mol) was treated with phosphoric acid (100 g) and heated at 145° C. under vacuum (170 mbar). While 1-isobutylcyclohex-1-ene and water distilled (boiling point 60° C.), a second fraction of 1-isobutylcyclohexanol (492 g, 3.15 mol) was added dropwise in the reaction flask. At the end of the addition, the thick reaction mixture was diluted with paraffin oil (100 ml) and additional phosphoric acid (50 g) and heated further (vacuum from 170 to 40 mbar). The distillate was decanted and the water phase extracted with pentane (100 ml). The combined org. phases were dried (MgSO4) and the solvent evaporated to give 1-isobutylcyclohex-1-ene (448 g, 78%).

Quelle