4-Chlorobenzonitrile → 4-Fluorobenzonitrile

Participants

Reaction Steps

In a 250 ml flange flask and fitted with an impeller stirrer, 69.6 g (1.2 mol) of potassium fluoride, 6.9 g (0.02 mol) of tetrabutyl-phosphonium bromide, 13.8 g (0.02 mol) of dimethyldi(ethoxypolyoxypropyl)ammonium chloride, 13.8 g (0.028 mol) of polyethylene glycol dimethyl ether 500 and 20 g of xylene were metered at 120° C. into the melt of 137.6 g (1.0 mol) of 4-chlorobenzonitrile. After stirring for 30 minutes, the reaction suspension was azeotropically dried by distilling off the xylene under vacuum. The reaction suspension was stirred for 30 hours at 190° C. Amount of 4-fluorobenzonitrile formed: after 9 hours: 12 GC area-% after 30 hours: 48 GC area-%, besides 45 GC area-% of unreacted 4-chlorobenzonitrile.

Provenance & Evidence