Reaction #742283

Reaction equation

Phosphoric acid

1,4-dimethyl-4-vinyl-cyclohexene

→

2,5-dimethyl-bicyclo[3.2.1]oct-2-ene

Solvents

toluene

Conditions

Workup

1. 1
   OtherThe reaction mixture was subsequently quenched with a solution of sodium hydroxide (NaOH)
2. 2
   OtherThe organic layer was separated
3. 3
   Dryingdried over sodium sulfate (Na2SO4)

Procedure

Phosphoric acid (H3PO4, 145 g, 1.48 mol) was added to a solution of 1,4-dimethyl-4-vinyl-cyclohexene (403 g, 2.96 mol, commercially available from Evonik Industries) in toluene (500 mL) and refluxed for 6 hours. The reaction mixture was subsequently quenched with a solution of sodium hydroxide (NaOH). The organic layer was separated, dried over sodium sulfate (Na2SO4), and fractionated to provide 2,5-dimethyl-bicyclo[3.2.1]oct-2-ene (280 g) having a boiling point of 87° C. at a pressure of 27 mmHg

Source