Synthesis and Structural Characterization of Tantalum(IV) Amido Compounds

Tantalum(IV) amido complexes have been synthesized from Ta(V) precursors. Ta(N(SiMe(3))(2))(2)Cl(3) reacts with Na/Hg to give Ta(N(SiMe(3))(2))(2)Cl(2), and Ta(NEt(2))(2)Cl(3) reacts with LiNPh(2) and Na/Hg to yield Ta(NPh(2))(2)(NEt(2))(2). Ta(N(SiMe(3))(2))(2)Ph(2) is prepared by reacting Ta(N(SiMe(3))(2))(2)Cl(2) with LiPh. Attempts to prepare other organometallic derivatives failed to yield clean products. X-ray crystallographic studies show that Ta(N(SiMe(3))(2))(2)Cl(2), Ta(N(SiMe(3))(2))(2)Ph(2), and Ta(NPh(2))(2)(NEt(2))(2) have distorted tetrahedral geometries.