From aromatics to aromatic amines: nature chemistry reports the new breakthrough of Jiaoning research team of Peking University on the utilization of bulk chemical raw materials

Recently, nature chemistry, a famous international academic journal, published on-line the breakthrough results of Professor Jiao Ning's research team entitled "from alkylarenes to anilinesvia site directed carbon carbon amination" (DOI: 10.1038 / s41557-018-0156-y) in the State Key Laboratory of natural and Biomimetic Drugs of Peking University The new application of aromatics bulk chemical raw materials has been researched and developed, which provides a new synthesis idea for the preparation of aniline compounds through inert C-C bond transformation, and is expected to provide a new strategy and new process for the preparation of aromatic amines and cyclohexanone, which are important basic raw materials in the fields of Medicine and materials Aniline, as an important organic synthesizer and basic chemical raw material, is widely used in the fields of dyes, medicine, pesticides, explosives, spices, rubber vulcanization accelerators and so on There are more than 300 kinds of chemical products made from it, among which the application fields of polyurethane, a new type of organic polymer material, which enjoys the title of "the fifth largest plastic", involve light industry, chemical industry, electronics, textile, medical treatment, building materials, automobile, national defense, aerospace, aviation and other important industries At present, the global demand for aniline is more than 5 million tons per year, so the development of efficient synthesis methods for aniline is of great significance and application prospects As an important precursor of caprolactam and nylon, the global annual demand of cyclohexanone has reached 5 million tons Traditional industrial methods need different processes to prepare these two important chemical products, and the reaction conditions are harsh The Jiaoning research team used their "nitrogen reaction" strategy (acc chem Res 2014, 47, 1137), a new way of introducing nitrogen atom and oxygen atom into alkylaromatics through carbon carbon bond breaking is innovatively realized, and the problem of selectivity of electron rich substituted aniline and synthesis of electron deficient aniline in traditional nitrification / reduction method is solved (Fig 1 ）In particular, the new reaction of cyclohexylbenzene to aniline and cyclohexanone has been completed for the first time, thus a new process has been developed for the high added value conversion and utilization of hydrocarbons in petroleum products (Fig 1) Figure 1 A new method of alkylaromatics carbon bond amination (source: State Key Laboratory of natural and Biomimetic Drugs, Peking University) C-C bond is the most basic chemical bond for organic compounds Its high bond energy has long restricted the conversion of alkylaromatics, based on C-C The activation of bonds has been widely concerned by chemists and is one of the most challenging research fields This work has successfully achieved the goal of converting bulk chemical raw materials into high value-added chemical products through C-C bond fracture with high efficiency and selectivity Lignin is the second most abundant and renewable aromatic polymer in nature It has been regarded as the waste of papermaking industry This method can extract useful aromatic ring fragments from lignin effectively, which provides an important means for degradation of lignin and extraction of high value-added compounds (Fig 2a) ）Its mild and efficient reactivity makes the method applicable to the synthesis and modification of complex molecules and drugs, providing a simple and efficient basis for the discovery of drug lead compounds and the creation of new drugs (Fig 2b) Fig 2 Liu Jianzhong, a 2015 doctoral candidate, is the first author of this paper The research is supported by the 973 Program of the Ministry of science and technology and the key program of NSFC.