| 摘要 |
NEW MATERIAL:A compound shown by formula I (X is group shown by formula II, formula III or anhydride thereof). EXAMPLE:m-Phenylenebissuccinic acid. USE:A polyimide raw material, plasticizer and epoxy curing agent. PREPARATION:Isophthalaldehyde obtained from metaxylylenediamine is reacted with ethyl cyanoacetate in the presence of piperidine as a catalyst to give 1,3-bis(beta-cyano-beta-ethoxycarbonylvinyl)benzene shown by formula IV, which is dispersed into ethanol, reacted with an aqueous solution of KCN at room temperature, made strongly acidic by addition of conc. hydrochloric acid and water and ethanol are distilled away under reduced pressure. Conc. hydrochloric acid is added to the residue, which is heated under reflux to give metaphenylenebissuccinic acid.
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