Monosubstituierte Derivate des Halbsandwich-Komplexes Cp*Ta(CO)4 - Vergleich mit den analogen Vanadiumverbindungen Cp*V(CO)3L und Röntgenstrukturanalyse des γ-Picolin-Komplexes Cp*V(CO)3(NC5H4-Me(4)) / Monosubstituted Derivatives of the Halfsandwich Complex Cp*Ta(CO)4 - Comparison with the Analogous Vanadium Compounds Cp*V(CO)3L and X-Ray Structural Analysis of the γ-Picoline Complex Cp*V(CO)3(NC5H4-Me(4))

Abstract

The photo-induced substitution of a CO ligand in Cp*Ta(CO)4 (1) has been used to prepare a series of Cp*Ta(CO)3L (2) complexes, in which the two-electron ligand L includes, e.g., isonitriles, sulfanes, cyclic ethers, phosphanes and pyridines. The complexes (2a-y) were characterized by their v(CO) frequencies and their 1H and 13C NMR spectra, and were compared - if possible - with the corresponding vanadium complex, Cp*V(CO)4 (3) and its derivatives, Cp*V(CO)3L (4). The molecular structure of the 4-picoline complex Cp*V(CO)3(NC5H4-Me(4)) (4r) has been determined by X-ray crystal structure analysis.