Zeolites for acylation reactions with carboxylic acid derivatives

PETR 114

M. Bejblová, jiri.cejka@jh-inst.cas.cz, D. Procházková, J. Vlk, and J. Čejka, jiri.cejka@jh-inst.cas.cz. J. Heyrovský Institute of Physical Chemistry, Academy of Science of the Czech Republic, Prague, CZ-182 23, Czech Republic
Zeolites with different structure and concentration of acid sites were investigated in liquid phase Friedel-Crafts acylation of ferrocene, toluene and cyclohexene derivatives. It was found that the conversion increases from 10-membered zeolites to 12-membered zeolites as well as from mono-dimensional to three-dimensional zeolites of the same pore size entrances.

The effect of the chain length of acylation agent on the conversion was investigated over large pore zeolite Beta with Si/Al ratio 12.5 as well. Acetic, propionic, butyric, hexanoic, isobutyric, 2-ethylisobutyric and benzoic anhydrides and acetyl, propionyl, butyryl, hexanoyl, octanoyl, decanoyl, isobutyryl and benzoyl chlorides were used as acylating agents for these reactions. It was found that the conversions of ferrocene and cyclohexene were very similar from acetic to butyric anhydride and then decreased with father increasing of chain length. The selectivity to 1-acylferrocene was in all cases 100 %. The selectivity to acylcyclohexene was up to 45 %. In the case of toluene acylation, the conversion of acylation agent increased with the chain length of acylating agent. The selectivity to para-isomers increased with the chain length and also with branched chains.