Studies Of Reactions Of Tantalum(V) Metallaheterocycle Complex With Carbon Dioxide And Silanes

dearly transition metallaheterocycle amino complexes are an important classof complexes. Metal nitrides, metal silicide and metal oxides which prepared fromthem have potential applications in microelectronic materials. In addition, d0earlytransition metallaheterocycle amino complexes play very important roles in carbondioxide fixation and activation, C-H bond activation and catalytichydroaminoalkylation reactions as well. In this thesis, we explored the novelchemical properties of tantallaheterocycle complexes through the studies of thereactions of tantallaheterocycle complex (Me2N)3Ta[CH2Si(Me2)NSiMe3](1) withcarbon dioxide and silanes.Firstly, an unusual tantalum(V) silicon carbonate imide complex (Me2NCO2)2(Me3SiN)Ta[CH2Si(Me2)OOCNMe2](2) was obtained by the insertion reactions oftantalum(V) metallaheterocycle complex (Me2N)3Ta[CH2Si(Me2)NSiMe3](1) withcarbon dioxide. In this reaction, we find three CO2molecules insert into Ta-Namidebonds firstly, then one of the Me2NCO2-attack Si-N bond because of the large sterictension, and therefore resulted in the Si-N bond broken to generate Ta=N bond andSi-O bond, respectively. This complex has been structurally characterized by NMR,elemental analysis, and single crystal X-ray diffraction.Secondly, we find that the reaction of (Me2N)3Ta[CH2Si(Me2)NSiMe3](1) withphenylsilane will produce H-bridging complex (Me2N)2[(Me3Si)2N]Ta[-H]2(-C-2-CHSiMe2NSiMe3)Ta(NMe2)2(3). Deuterium labeling experiments indicated thatH-D exchange was found between Ta-D and all the methyl groups. Inaddition,(Me2N)2[(Me3Si)2N]Ta[-H]2(-C-2-CHSiMe2NSiMe3)Ta(NMe2)2(3) isunstable at room temperature, it will convert into a new complex [(Me2N){(Me3Si)2N}Ta(μ-H)(μ-N-η2-C,N-CH2NMe)(μ-C-η2-C,N-CHSiMe2NSiMe3)Ta(NMe2)2](5)through H2elimination in seven days. This complex has been structurallycharacterized by NMR, elemental analysis, and single crystal X-ray diffraction.