| 摘要 |
PURPOSE:To obtain the titled compound useful as a synthetic raw material for polyimide resin, etc., from a relatively inexpensive raw material in a short time in high yield, by carrying out dechlorination dimerization reaction of a 4-chloro-orthophthalate under a specific condition. CONSTITUTION:The objective 3,3',4,4'-biphenyltetracarboxylic acid salt is produced by reacting a 4-chloro-orthophthalic acid salt in an aqueous solution of alkali hydroxide at 80-110 deg.C for 0.5-5hr in the presence of a polyhydric alcohol (e.g. glycerol) and a catalyst produced by supporting metallic palladium on a carrier such as alumina, silica, etc. The reaction is carried out by using 3-6mol of the alkali hydroxide, 4-8m-mol of the catalyst (in terms of palladium) and 10-50g of the polyhydric alcohol based on 1mol of the 4-chloro- orthophthalic acid salt. |
