Selective transalkylation of biphenyl over solid acid catalysts Original Research Article

The preparation of 4,4′-diethylbiphenyl (4,4′-DEBp) in high isomer ratio (86%) and good yield (53 mol-%) was accomplished by transethylation of biphenyl with triethyl- or tetraethylbenzene over H-Y zeolite catalyst at relatively low temperatures. This high 4,4′-DEBp selectivity and yield are not attributed to the shape selectivity of H-Y zeolite, but to an effective modification of the transethylation conditions. No selectivities were observed in the ethylation of biphenyl with ethylene over mordenite, a shape selective catalyst effective for preparation of 4,4′-diisopropylbiphenyl by the corresponding alkylation.