N-heterocyclic Carbene-palladium(Ⅱ)-1-methylimidazole Complex Catalyzed C-H Bond Functionalization Of Fluorenes And(benzo)oxazoles

This thesis mainly introduces the N-heterocyclic carbene-palladium(II)-1-methylimidazole [NHC-Pd(II)-Im] complex catalyzed C-H bond functionalization of fluorenes and(benzo)oxazoles, which can be divided into three parts:(1) We found that NHC-Pd(II)-Im complex was an efficient catalyst for the direct C-H bond arylation of fluorenes with aryl chlorides. This method is superior over reported ones, giving an economical, simple and efficient method for the arylation of fluorenes and thus it will enrich the application of the NHC-Pd(II) complexes in C-H bond direct arylation.(2) The further oxidation and alkylation of the mixture of the NHC-Pd(II)-Im complex catalyzed direct C-H bond arylation between fluorenes and aryl chlorides was achieved in a one-pot procedure. Therefore, two different substituents can be introduced in the C9-position of fluorenes, and will thus guild the functionalization of fluorenes.(3) It was found that NHC-Pd(II)-Im complex was also an efficient catalyst for the direct C-H bond benzylation between(benzo)oxazoles and benzyl chlorides. Diarylmethanes are abundant in pharmaceuticals and biologically active compounds. Therefore, the realization of such method gives a simple and efficient method for the synthesis of diarylmethanes and will enrich the application of NHC-metal complexes in the direct C-H bond benzylation of heterocyclic compounds.