| N-Heterocyclic carbenes (NHCs) are similar with traditional alkyl phosphine ligands in electronic properties. However, due to their aromaticity, stability and strong coordination ability, they have been widely used in metal organic chemistry and catalysis. For NHC precursor imidazolium salts can form (C-H)+…anion ionic hydrogen bonds, they have been widely used in host-guest recognition, supramolecular devices.In this thesis, we focused on cyclophane-type benzimidazolium salts and NHC-nickel complexes. We carried out research from two parts as listed below:1. Synthesis of benzimidazolium functionalized BINOL and its application in host-guest recognitionA cyclophane-type benzimidazolium functionalized BINOL fluorescent receptor was developed in host-guest recognition. The highly selective responses to H2PO4-could be applied to the discrimination among F-, Br-, I-, NO3-, Ac- and HSO4-. Due to the BINOL's chiral frame, we chose chiral mandelic acid as chiral guest to explore its use in chiral recognition. From the results of fluorescent experiments, no obvious differences were observed.2. Synthesis of NHC-nickel complexes and their application in Friedel-Crafts alkylation The ligand precursors could be synthesized from 2-chloromethyl-1-ethyl-benzimidazole with N-(6-methylpyridyl-methyl)imidazole and N-(6-methylpyridylmethyl)benzimidazole. Then the NHC-nickel complexes were prepared by metal exchange from silver-carbene. Complexs exhibited good activities in catalyzing the Friedel-Crafts reaction of indole withβ-nitrostyrene under mild conditions in moderate-to-good yields (up to 96% yield).In conclusion, we developed a new cyclophane-type benzimidazolium salt receptor and two kinds of NHC-nickel complexes. The good results of their applications in host-guest recognition and catalysis provided broad prospects for further researchs.
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