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METHOD FOR PRODUCING 3,3',4,4'-BIPHENYLTETRACARBOXYLIC ACID DIANHYDRIDE
METHOD FOR PRODUCING 3,3',4,4'-BIPHENYLTETRACARBOXYLIC ACID DIANHYDRIDE
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机译:制备3,3',4,4'-联苯二羧酸二羧酸二酐的方法
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摘要
PROBLEM TO BE SOLVED: To provide a method for producing 3,3',4,4'-biphenyltetracarboxylic acid dianhydride in a high catalytic yield (Pd yield), capable of reducing an amount of Pd attached to a reaction vessel in a dimerization reaction of an o-phthalic diester, including the dimerization of the o-phthalic diester by successively replenishing a catalytic component. ;SOLUTION: This method for producing 3,3',4,4'-biphenyltetracarboxylic acid dianhydride comprises (a) a process for dimerizing an o-phthalic diester in the presence of a catalyst obtained from a powdery palladium salt having 0.5 m2/g specific surface area and a basic bidentate ligand with adding at least one kind of the components and then separating and collecting 3,3',4,4'- biphenyltetracarboxylic acid tetraester from the reaction system and (b) a process for hydrolyzing the obtained 3,3',4,4'-biphenyltetracarboxylic acid tetraester and drying and anhydrizing obtained 3,3',4,41-biphenyltetracarboxylic acid.;COPYRIGHT: (C)2001,JPO
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