To an oven dried 3-neck reflux apparatus equipped with a thermometer and an addition funnel quickly add 130 mL of anhydrous benzene and 3.4 g of anhydrous aluminum trichloride, pour 25.6 g of dry isopropyl bromide and 50 mL of dry benzene into the addition funnel. After the addition of the solution reflux the solution for 3h, thereafter the reflux is stopped by pouring in 50 mL of 10% HCl. The mixture is poured into a separatory funnel and the aqueous phase is discarded, the organic layer is washed with dilute NaOH solution until the discarded water is neutral. The organic layer is dried with some anhydrous magnesium sulfate, the solution is distilled and the fraction is collected between 145 and 160°C.
Addition of the bromide
Refluxing the mixture and adding the HCl
The pure distilled cumene