Alkylation of Phenols on Fe2O3 and Cr2O3

Ferric oxide and chromium oxide, were found as new alkylation catalysts of phenols. The activity and the selectivity of these oxide catalysts were examined by liquid-phase reaction. Methylation of phenol, cresol, xylenol, and α-naphthol was carried out in an autoclave at 400°, using methanol as an alkylating agent. The selective methylation of phenols to their ortho-position took place, and o-cresol and 2, 6-xylenol were obtained selectively from phenol. Their yield reached 70% after 5 hr. Ferric oxide was effective only in methanol, whereas chromium oxide was available for C1 to C4 alcohols. From the distribution of methylated products on various oxides, an outline of oxide-catalyzed alkylation was presented.