M-Xylene → 5-Isopropyl-m-xylene

Participants

Reaction Steps

A reaction was carried out using a Hastelloy C autoclave having an inside volume of 6,000 mL and equipped with an electromagnetic stirrer, a baffle plate, a gas blowing port and a liquid feed port in the same manner as that in Example 1. For the reaction, 2,003 g (18.9 moles) of metaxylene, 943 g (47.1 moles) of anhydrous HF and 715 g (17.0 moles) of propylene were used. After the reaction was terminated, the reaction mixture was fed at a rate of 300 mL per hour together with 600 g per hour of benzene to a distillation column (column internal pressure: 0.38 MPa, 122° C.) in which benzene was recirculated. A benzene solution of 3,5-dimethylcumene was separated and collected from the bottom of the column, while discharging BF3 from the top and HF from a discharge port below the condenser. The benzene solution of 3,5-dimethylcumene obtained from the bottom of the column was condensed using an evaporator and then distilled (column internal pressure: 0.0133 MPa, stage number: 12, a reflux ratio: 10) to obtain 1,925 g of desired 3,5-dimethylcumene (distillation temperature: 129° C.). The purity was 99.2% and isolation yield was 76%.

Provenance & Evidence