Abstract:

p-Chlorobenzaldehyde is an intermediate for many fine chemicals and it is widely used in the production of pharmaceuticals, agricultural chemicals, and dyes. It is significant but also very challenging to develop a green process for the catalytic synthesis of p-chlorobenzaldehyde. Herein synthesis of p-chlorobenzaldehyde by catalytic oxidation of p-chlorotoluene was reviewed. Emphasis was put on the oxidation of p-chlorotoluene with H₂O₂, air/O₂ or electro-oxidation, and biomimetic catalytic method. The advantages and disadvantages of these methods were described systematically, and the feasibility and existing problems in their industrial development were pointed out. In addition, the selective oxidation of p-chlorobenzene to p-chlorobenzaldehyde by photocatalysis was also introduced. After comparison of different synthesis methods, we point out that the liquid phase oxidation of p-chlorobenzene by using H₂O₂ and molecular oxygen as oxidant shows good industrial application prospect. Meanwhile, the electro-oxidation and biomimetic catalytic oxidation will provide new techniques for the preparation of p-chlorobenzaldehyde.

Key words: catalysis, oxidation, selectivity, p-chlorobenzene, p-chlorobenzaldehyde

摘要：

对氯苯甲醛是一种广泛用于医药、农药和染料的精细化工中间体，发展其绿色合成工艺极具挑战性和重大意义。本文较为系统地综述了催化氧化对氯甲苯为对氯苯甲醛的制备方法，重点阐述了H₂O₂氧化法、空气/氧气氧化法、电解氧化法和仿生催化氧化法的工艺条件，比较了间接电氧化合成方法中的各种金属媒质，讨论了各种制备方法的优缺点，分析了其相应的合成方法在工业开发上的可行性及存在的问题。此外，简要介绍了利用光催化法选择性氧化对氯甲苯合成对氯苯甲醛的方法。通过对几种合成方法的比较，指出以H₂O₂和分子氧为氧化剂液相催化氧化对氯甲苯来合成对氯苯甲醛是较为经济、环保的合成方法，电解氧化法和仿生催化氧化法将为对氯苯甲醛制备提供另一条新型技术途径。

关键词: 催化, 氧化, 选择性, 对氯甲苯, 对氯苯甲醛