反応 #2146731

反応方程式

phosphoric acid

1-isobutylcyclohexanol

phosphoric acid

1-isobutylcyclohexanol

→

1-isobutylcyclohex-1-ene

溶媒

反応条件

後処理

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
   温度heated further (vacuum from 170 to 40 mbar)
4. 4
   その他The distillate was decanted
5. 5
   抽出the water phase extracted with pentane (100 ml)
6. 6
   乾燥phases were dried (MgSO4)
7. 7
   その他the solvent evaporated

実験手順

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%).

出典