| abstract |
PURPOSE:The dehydrogenative dimerization of aromatic compounds bearing benzene nucleus is effected in the presence of an organic palladium, oxalic acid, and molecular oxygen under pressure, thus producing biphenyl compounds in high yield. CONSTITUTION:In the production of biphenyl compounds by dehydrogenative dimerization of aromatic compounds, the reaction is effected in the presence of an organic palladium salt, oxalic acid and molecular oxygen under pressure. The aromatic compounds bear bezene ring and 1-2 alkoxycarbonyl groups of 1-5 carbon atoms. As the organic palladaium salt, palladium acetate is especially suitable and the amount is 0.01-100 millimoles per mol of the staring material. The amount of the oxalic is 0.05-50 moles per mole of the organic palladium salt. The reaction pressure is 4-400kg/cm<2> and temperature is room one to 300 deg.C. |