Synthesis,Structure And Reactivity Studies Of Titanium Imido Supported Yttrium Monoalkyl Complexes

This thesis mainly studied the synthesis,characterization and reactivity of titanium imido supported yttrium monoalkyl complexes,which included the following parts:1.A dimeric titanium imido complex 1 was synthesized through the salt elimination/αH abstraction reaction between the LiHNtBu and TiCl4(THF)2.One-electron reduction of the Ti(Ⅳ)imido dimer with KC8 or Na afforded two mixed-valent Ti(Ⅳ)-Ti(Ⅲ)imido complexes.These complexes were fully characterized by 1H,13C{1H} NMR spectroscopy methods,elemental analysis and X-ray single crystal diffraction studies,as well as EPR spectroscopy for the mixed-valent imidos.2.Alkane elimination reaction between the Ti(Ⅳ)imido dimer and yttrium trisalkyl complex Y(CH2SiMe3)3(THF)2,afforded the titanium imido supported yttrium monoalkyl complex,which was fully characterized by NMR spectroscopy,elemental analysis and single crystal X-ray diffraction studies.The reactivity of this complex with[Et3NH][BPh4],(EtO)3SiH and terminal alkynes led to the formation of titanium imido supported yttrium cation,ethoxide and terminal alkynyl complexes,respectively.While the reaction with nitriles afforded an insertion product.All complexes were characterized by NMR spectroscopy,elemental analysis as well as single crystal X-ray diffraction studies.These reactions demonstrated the robustness of the titanium imido as supporting ligand.3.Bipyridiene ligand supported precursor(dtbpy)TiCl4 was utilized in the reaction with LiHN’Bu,which led to the isolation and characterization of an"ate-type" titanium terminal imido complex.Further reaction with rare-earth metal tris(alkyl)complex was also briefly explored.