Synthesis Of N-heterocyclic Carbene Palladium Complexes And Application In Cross-Coupling Of C-C,C-N

N-heterocyclic carbene (NHC) and N-heterocyclic carbene metal complexes shows excellent catalytic activity in the field of many catalysis reactions. It is known that the chemistry of the N-heterocyclic carbenes and their transition metal complexes is one of the hotest topics in the modern coordination chemistry and homogeneous catalysis. This paper mainly contains three parts:Part one: Synthesis and characterization of new type N-heterocyclic carbene palladium complexesTwo new type N-heterocyclic carbene palladium complexes (3a,3b) were synthesized from N,N-dimethylbenzylamine easy available though improved method and characterized by NMR, MS, IR, at the same time the structure of 3a was confirmed by X-ray analysis. Characterization results shew the chemical bond was existed between carbene C and Pd, at the same time the coordination bond of Pd and N atom of N,N-dimethylbenzylamine.Part two: new type N-heterocyclic carbene palladium complexes application in Buchwald-Hartwig cross-coupling reactionCatalytic Buchwald-Hartwig cross-coupling of aryl halides with amines and nitrogen-containing reagents had been successfully performed by the carbene palladium complexes Under the optimized reaction conditions of 3a as catalyst, NaOtBu as base, 1,4-dioxane as solvent. Studying results indicated that the nearly reasonable isolated yields were obtained in the Buchwald-Hartwig Cross-coupling with high efficiency in the present of carbene. The method had shown high catalytic activity, moderate reaction conditions, a little dosage catalyst (l-2mol%) and no undesired dehalogenation byproducts and palladium black. The ancillary ligands surrounding palladium allowed for changes in catalytic performance.Part three: new type N-heterocyclic carbene palladium complexes application in Suzuki-Miyaura cross-coupling reactionWe investigated that N-heterocyclic carbene palladium complexes was applied in Suzuki-Miyaura Cross-coupling and optimized reaction conditions. Experiment Results...