Liquid Etherification of Alkoxybenzyl Alcohols, Cinnamyl Alcohols and Fluorinated Phenylalkenols with Platinum on Carbon (Pt/C) and Palladium on Carbon (Pd/C)

In the presence of either Pd/C or Pt/C, 4-alkoxybenzyl alcohols, 4-alkoxy-phenylalkyl alcohols and cinnamyl alcohols undergo liquid etherification to bis(4-alkoxybenzyl) ethers, bis[(4-alkoxybenzyl)alkyl] ethers and bis(cin-namyl) ethers at temperatures of 100°C - 135°C. In a number of cases, Pt/C and Pd/C as catalysts, also when they are doped with Ru, show distinct differences when the reactions run in air, with an oxidative dehydrogenation of the alcohols as side-reaction, yielding the corresponding ketones and aldehydes as by-products. Also, the reactivity of fluorinated phenylalkenols under these conditions has been investigated. Furthermore, the immobilization of alkyl aryl ethers on silica within a column with passage of hexane as solvent was found to lead to the formation and elution of styrenes from the column in fair yield.