A DFT study of the acid-catalyzed conversion of 2,5-dimethylfuran and ethylene to p-xylene

► The conversion mechanism of 2,5-dimethylfuran and ethylene to p-xylene is explored. ► p-Xylene is obtained by dehydration of a Diels-Alder oxa-norbonene cyclo-adduct. ► Lewis acids are predicted to be very effective Diels-Alder catalysts. ► Brønsted acids have no catalytic effect on the Diels-Alder reaction. ► Brønsted acids are found to be very effective dehydration catalysts.