Isomerisation of 1,4-dichlorobenzene using highly acidic alkali chloroaluminate melts

Abstract

The isomerisation reaction of 1,4-dichlorobenzene leading to the thermodynamically favoured and technically desired 1,3-dichlorobenzene has been studied comparing highly acidic chloroaluminate melts with organic imidazolium and alkali metal ions. Interestingly, the inorganic melts show much higher reactivity and full recyclability if small AlCl₃ losses are compensated and the reaction is carried out under slight HCl pressure.