A reflux apparatus equipped with a Dean-Stark water-trap is set up. Where to 39.6 mL of piperidine, 34.5 mL of cyclohexanone, 500 mg of p-toluenesulfonic-acid and 100 mL toluene are added. The mixture is refluxed until all of the water is collected in the water trap. The solution is then cooled down and poured into a separatory funnel and is washed with 30 mL of water. The organic layer is then dried and distilled under vacuum. ~108°C fraction is collected.
Azeotropic removal of water
Distillation of the product