申请人:UBE INDUSTRIES, LTD.
公开号:EP0439616A1
公开(公告)日:1991-08-07
A 3,4,3'4'-substituted biphenyl compound represented by the general formula (II):
wherein, one of R¹ and R² is a -CH₃ group and the one other is a -COOR⁵ group, -COOH group, or -COCl group, and one of R³ and R⁴ is a -CH₃ group and the other one is a -COOR⁵ group, -COOH group, or -COCl group, is produced by the steps of oxidatively coupling an o-toluic acid alkyl ester in the presence of a catalyst containing a mixture of palladium salts with 1,10-phenanthroline or α,α'-bipyridine, a chelating product of a palladium salt with 1,10-phenanthroline, or a chelating products of a palladium salt with α,α'-bipyridine, in an atmosphere containing molecular oxygen, to selectively produce a 3,4,3',4'-substituted dimethyl biphenyl dicarboxylic acid dialkyl esters having a biphenyl ring structure; optionally converting this dialkyl ester compound to a corresponding dimethyl biphenyl dicarboxylic acid, and then optionally further converting this to a corresponding dimethyl biphenyl dicarboxylic acid dichloride.
通式(II)代表的 3,4,3'4'-取代联苯化合物:
其中,R¹ 和 R² 中的一个是-CH₃基团,另一个是-COOR⁵基团、-COOH 基团或-COCl 基团;R³ 和 R⁴ 中的一个是-CH₃基团,另一个是-COOR⁵基团、-COOH基团或-COCl基团,是通过以下步骤制得的:在含有钯盐混合物的催化剂存在下,将邻甲基苯甲酸烷基酯与1、10-菲罗啉或 α,α'-联吡啶的混合物、钯盐与 1,10-菲罗啉的螯合产物、或钯盐与 α,α'-联吡啶的螯合产物的催化剂存在下,在含有分子氧的气氛中,氧化偶联邻 甲苯甲酸烷基酯,选择性地生成具有联苯环结构的 3,4,3',4'-取代二甲基联苯二 羧酸二烷基酯;选择性地将这种二烷基酯化合物转化为相应的二甲基联苯二甲酸,然后选择性地进一步将其转化为相应的二甲基联苯二甲酸二氯化物。