Research On Transition-metal Palladium And Copper Catalyzed Cyanation Reaction

Nitriles are widely used organic synthesis intermediates. Because they are notonly important precursors to a variety of functional groups, such as aldehydes, amines,amidines, tetrazoles, amides, and other carboxy derivatives etc, but also appliedwidely as key intermediates in compounding various natural products, biologicallyactive molecules and designed functional materials. The traditional synthetic methodsof aromatic nitriles are Rosenmund von Braun reaction, Sandmeyer reaction andindustrial ammonia oxidation etc. However there are so many drawbacks in thesereactions, for example high temperature, dangerous process and a waste of metal.Recently, transition-metals (such as Pd、Ni、Cu、Zn、Rh etc.) catalyzed cyanationreactions have been rapidly developed, in the meantime the cyanide resource havebeen also developed from metallic cyanide sources (such as NaCN、 KCN、Zn(CN)2、K3Fe(CN)6, and TMSCN) to non-metallic sources (such as CH3CN, NCTS, DDQ etc).Herein, in our thesis we firstly introduce the application of nitriles and a series oftransition-metal catalyzed cyanation reactions.The experimental part of this chesis chapters includes three asptcts of content. Inthe first chapter, we developed the traditional Sandmeyer reaction. We used a series ofarenediazonium tetrafluoroborates as substrates, Cu2O as catalyst and TMSCN ascyanide source. The conditions of the cyanation reaction are mild and do not need anyligands, the substrates scope of which is wide and functional group toleratance arebroad, besides, the reaction is also suitable for heterocycle.In the second chapter, we used a series of arenediazonium tetrafluoroborates assubstrates, Pd(OAc)2and Ag2CO3to act as catalyst and oxidant, N-cyano-N-phenyl-p-toluenesulfonamide (NCTS) as non-metallic cyanide source. After a series ofexperiments, we have explored the optimizatied condition and utilized that we testedthe substrate scope of the cyanation reaction, of which functional tolerance is broadand the yields of aromatic nitriles are good enough.In the third chapter, we developed the cyanation reaction of aryl halides, includingaryl iodides and aryl bromides. In the reaction, PdCl2/Ag2O is catalytical system, andN-cyano-N-phenyl-p-toluenesulfonamide (NCTS) is “CN” source. Utilizing theoptimizing reaction we explored, we compound a series of nitriles from aryl halides.