| 摘要 |
<p>PURPOSE:To prepare the title compound useful as a raw material of aromatic polyimide, in high yield, with little formation of by-products, by the oxidative coupling of an ortho-phthalic acid ester in the presence of an organic palladium salt and 1,10-phenanthroline, etc. CONSTITUTION:The title compound is prepared by the oxidative coupling of an ortho-phthalic acid ester in an atmosphere containing molecular oxygen, at 50- 300 deg.C under 1-300atm., in the presence of (a) an organic palladium salt and 0.9-4mol, based on 1mol of the palladium salt, of 1,10-phenanthroline and/or alpha,alpha'-bipyridyl, or (b) a chelate of an organic palladium salt and 1,10-phenanthroline and/or alpha,alpha'-bipyridyl. The molar ratio of the organic palladium salt to 1,10- phenanthroline and/or alpha,alpha'-bipyridyl is pref. about 1:0.9-0.9:1.</p> |
