摘要 |
<p>Oxybisphthalic compounds such as 4,4'-oxybis(N-methylphthalimide) and 4,4'-oxybis(phthalic anhydride) are prepared from the corresponding nitro- or halo-substituted phthalic compounds by reaction with an alkanoate or carbonate salt in a substantially non-polar solvent and in the presence of a hexaalkylguanidinium salt as phase transfer catalyst. A carboxylic acid such as 4-chlorobenzoic acid may be used as an additional catalyst. Reaction rates and yields are higher than with other phase transfer catalysts.</p> |