本发明涉及一种以N-质子化己内酰胺为阳离子基团的Brφnsted酸性离子液体为催化剂和反应介质的催化环己酮肟经Beckmann重排反应制备ε-己 内酰胺的方法。在温和的反应温度和较短的反应时间内高转化率高选择性地生成ε-己内酰胺，而且该酸性离子液体可以重复使用。本发明由于使用以质子化的该反 应的产物为阳离子基团的酸性离子液体作为催化剂和反应介质，因而产物不再与酸性离子液体结合，反应结束后无需加碱中和，反应体系简单，不会造成环境污染， 酸性离子液体不腐蚀设备，离子液体的制备成本低，节约资源，具有很好的工业应用前景。

邓友全,郭术,杜正银,等. 催化环己酮肟重排制备ε-己内酰胺的方法. Cn1781908. 2007.

The Beckmann rearrangement of cyclohexanone oxime to afford caprolactam in a novel caprolactam-based Brønsted acidic ionic liquid as catalyst and reaction medium proceeded with high conversion and selectivity at 100 ℃. The occurrence of the Beckmann rearrangement of cyclohexanone oxime in such a Brønsted acidic IL was also confirmed with in situ FT-Raman observation. The key point is that the caprolactam product was one component of the ionic liquid, and a dynamic exchange between the resulting caprolactam product and the caprolactam from the ionic liquid is expected. Therefore, the strong chemical combination between the caprolactam product and the acidic ionic liquid was greatly decreased and the desired product in the solid was recovered through extraction with organic solvent after the reaction.

★★★★☆Guo S,Du ZY,Zhang SG,et al. Clean Beckmann Rearrangement Of Cyclohexanone Oxime In Caprolactambased Brønsted Acidic Ionic Liquids[J]. Green Chemistry,2006,8:296-300.

Beckmann rearrangement of several oximes catalyzed by metaboric acid was studied in room temperature ionic liquids. Especially for conversion of cyclohexanone oxime into e-caprolactam, excellent conversion and selectivity were obtained.

★★★☆☆ Keywords: Beckmann rearrangement; Oxime; Metaboric acid; Ionic liquid

★★★☆☆ S. Guo, Y. Deng / Catalysis Communications 6 (2005) 225–228.