Applications Of Palladium-Catalyzed Isocyanide Insertion Reaction In The Synthesis Of Important Organic Compounds

Object:To investigate whether isocyanides could be used for multiple insertion reaction,and whether isocyanides could be used as carboxyl source in the oxidative palladium-catalyzed reaction involving isocyanide insertion into C-B bonds,which will expand their applications in organic synthesis.To find an efficient and low-toxic cyanating reagent,develop a convenient and economy cyanation reaction for synthesis of aromatic nitriles and allylic nitriles.Methods:1.By screening the factors that affected the reaction,such as solvent,catalyst,temperature,etc.,to find the optimal conditions for palladium-catalyzed synthesis ofα-iminonitriles and aromatic carboxylic acid.2.By changing the catalyst,solvent,oxidant,etc.,to optimize the reaction condition of sp²C-H bond cyanidation withα-iminonitriles as the cyano source.Results:1.The optimal conditions for the synthesis ofα-iminonitriles by palladium-catalyzed double isocyanide insertion reaction are aryl halides,t-butyl isocyanide,PdCl₂,PCy₃,Cs₂CO₃,4 A molecular sieves and anhydrous DMF.In addition,for the reaction of synthesis of aromatic carboxylic acids,the best conditions are aromatic boronic acid,Pd（OAc）₂,anhydrous Cu（OAc）₂,4 A molecular sieves and anhydrous DMF.2.According to screening results,the optimal conditions for the synthesis of aromatic nitriles are 2-phenylpyridine,α-iminonitriles,Pd（OAc）₂,Cu（TFA）₂ and THF.The best reaction conditions for the synthesis of allylic nitriles are 2-（1-phenyl-vinyl）-pyridine,α-iminonitriles,Cu（TFA）₂ and THF.Conclusion:1.In this paper,we overcame the challenge of isocyanides polymerization in the presence of transition metal in double isocyanides insertion,and achieved isocyanides as carboxyl source in the oxidative palladium-catalyzed reaction involving isocyanide insertion into C-B bonds.2.We have discovered a simple and efficient palladium-catalyzed C-H cyanation reaction of arenes and olefins by usingα-iminonitrile as a new cyano reagent.