title: Facile synthesis of nitrogen tetradentate ligands and their applications in Cu(I)-catalyzed N-arylation and azide-alkyne cycloaddition.
abstract: Five new tetradentate ligands [NNNN] with benzimidazolyl-imine or amine nitrogen donors have been synthesized in good yields under mild conditions from easily available substrates. trans-N,N'-bis(1-Ethyl-2-benzimidazolylmethylene)cyclohexane-1,2-diimine is the best accelerating ligand in this series that supports the Cu(I)-catalyzed Ullmann N-arylation and the direct three-component azide-alkyne cycloaddition reaction to give the corresponding substituted imidazole, pyrazole, and triazole in high yields. Single-crystal X-ray diffraction analysis of its complex with CuI reveals a novel one-dimensional coordination polymer of the metal chain bridged alternately by the [NNNN] ligand and diiodides.
authors.affiliation: Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore.
authors.forename: Fuwei
authors.initials: F
authors.lastname: Li
authors.forename: T S Andy
authors.initials: TS
authors.lastname: Hor
mesh_terms: D000480:Alkynes / Q000737:chemistry*; D001386:Azides / Q000737:chemistry*; D002384:Catalysis; D003300:Copper / Q000737:chemistry*; D008024:Ligands; D015394:Molecular Structure; D009584:Nitrogen / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry; D014961:X-Ray Diffraction
chemical_list: D000480:Alkynes; D001386:Azides; D008024:Ligands; D011108:Polymers; D003300:Copper; D009584:Nitrogen