| 摘要 |
PURPOSE:To safely obtain in high yield the title compound as an industrial raw material for various applications without the need for metallic powder etc. by dimerization, through dehalogenation, of a 4-hydroxy-4'-halogenobiphenyl in a solvent in the presence of a catalyst and e.g. an alkali metal hydroxide. CONSTITUTION:The objective compound of formula II can be obtained by dimerization, through dehalogenation, of a 4-hydroxy-4'-halogenobiphenyl of formula I (R is H, alkyl or acyl; X is halogen) or its derivative in an inert organic polar solvent (pref. methanol, ethanol, ethylene glycol, etc.) using palladium as catalyst in the presence of at least one compound selected from hydroxides, carbonates and bicarbonates of alkali metals and alkaline earth metals respectively (pref. sodium hydroxide or potassium hydroxide, esp. to be used as a 5-20wt.% aqueous solution), pref. furthermore in the presence of water at pref. 80-150 deg.C. |
