Ether Formation in the Hydrogenolysis of Hydroxymethylfurfural over Palladium Catalysts in Alcoholic Solution

Abstract

5-Hydroxymethylfurfural, a product from renewable feedstock, was subjected to hydrogenolysis over palladium catalysts in 1-propanol aiming at the synthesis of 2,5-dimethylfuran, a potential transportation fuel enhancer.Intermediates are 5-hydroxymethyl-2-(propyloxymethyl)furan, formed with high selectivity, and 5-methyl-2-(propyloxymethyl)furan.Acetals are assumed to be initially formed.Acetalisation and hydrogenolysis are catalysed by traces of a Brønsted acid.Important variables are the palladium support and the solvent.In 2propanol also ether formation takes place.In 1,4-dioxane mainly 2,5bis(hydroxymethyl)furan is formed, in water ring opening becomes a major reaction.The formation of some side-products is discussed.