The classical process for the rearrangement of substituted benzil to benzilic acid is performed in the presence of sodium or potassium hydroxide as a base using ethanol-ether as a medium. The reaction requires reflux temperature for complete conversion. However, these bases containing metallic ions and generate metallic containing effluent waste which may require additional expenditure for treatment. Moreover, because of corrosive nature of base, and use of flammable solvent, the safety measures are needed during large scale production. Another method also reported for benzilic acid rearrangement at 380° C. which is practically not feasible. The present invention describes the use of quaternary ammonium hydroxides as a base for the rearrangement of the substituted benzils to benzilc acids. It also avoids the use of solvent and reaction can be carried out at relatively lower temperatures. Because of the solvent free reaction condition it reduces the mass/volume of reaction mixture.
                            将取代苯并二酮重排生成苯并
甲酸的经典过程是在存在
钠或
钾氢氧化物作为碱的情况下,使用
乙醇-醚作为介质进行的。该反应需要回流温度才能完全转化。然而,这些含有
金属离子的碱会产生含
金属废
水,可能需要额外的费用进行处理。此外,由于碱的腐蚀性质和易燃溶剂的使用,在大规模生产过程中需要采取安全措施。另一种方法报告了在380°C下进行苯并
甲酸重排,但实际上是不可行的。本发明描述了使用季
铵氢氧化物作为取代苯并二酮重排生成苯并
甲酸的碱。它还避免了溶剂的使用,反应可以在相对较低的温度下进行。由于无溶剂的反应条件,它减少了反应混合物的质量/体积。