An efficient and convenient catalytic system for the aerobic oxidative lactonization of diols has been disclosed based on MnAl composite oxides (MnAlO_x) and O₂ without any additives in the study. This protocol is featured with simple catalytic system, as no any additives are needed, and it has high practical potential. The developed Mn-based reaction system can tolerate various diols with moderate to excellent yields of lactones. Based on a series of control experiments, a possible reaction path containing 2-(hydroxymethyl)benzaldehyde instead of 1,3-dihydroisobenzofuran as the predominant reaction intermediate has been proposed for the model lactonization of 1,2-benzenedimethanol. Electron transfer processes are probably taking place in the catalytic transformation based on a series of control experiments and characterization of the catalyst. The synergistic effect between Mn and Al was observed to be responsible for the high catalytic performance.

本研究公开了一种基于MnAl复合氧化物(MnAlO _x )和O _{2且不添加任何添加剂}的高效、便捷的二醇有氧氧化内酯化催化体系。该方案催化体系简单，无需任何添加剂，具有较高的实用潜力。开发的锰基反应系统可以耐受各种二醇，并具有中等至优异的内酯产率。基于一系列对照实验，为 1,2-苯二甲醇的内酯化模型提出了一条可能的反应路径，其中包含 2-(羟甲基)苯甲醛而不是 1,3-二氢异苯并呋喃作为主要反应中间体。根据一系列控制实验和催化剂的表征，电子转移过程可能发生在催化转化中。据观察，Mn 和 Al 之间的协同效应是其高催化性能的原因。