Struktur, Eigenschaften und NMR-spektroskopische Charakterisierung von Cp2Zr(Pyridin)(Me3SiCCSiMe3)†

Die Substitution des THF-Liganden in Cp2Zr(THF)(Me3SiCCSiMe3) (1) durch Pyridin ergibt den Komplex Cp2Zr(η1-NC5H5)(Me3SiCCSiMe3) (3). Im Gegensatz zu 1 ist Komplex 3 stabil in Kohlenwasserstoffen. In temperaturabhangigen 1H- und 13C-NMR-Spektren zeigt 3 in Losung dynamisches Verhalten durch eine Rotation des Alkin-Liganden. Zusatzlich tritt beim Losen von 3 in Pyridin ein Austausch zwischen koordinierten und freien Pyridin-Molekulen auf. Die Kristallstrukturanalyse von 3 belegt eine tetraedrische Koordinationsgeometrie am Zirkonium-Zentrum bestehend aus den Cp-, Alkin- und Pyridin-Liganden. Der Komplex 3 reagiert wie Verbindung 1 mit Wasser und Kohlendioxid zu gleichen Produkten. Structure, Properties, and NMR Spectroscopical Characterization of Cp2Zr(pyridine)(Me3SiCCSiMe3) Displacement of the THF ligand in Cp2Zr(THF)(Me3SiCCSiMe3) (1) with pyridine yields Cp2Zr(η1-NC5H5)(Me3SiCCSiMe3) (3). Unlike 1, the complex 3 is stable in hydrocarbon solvents. According to the temperature dependent 1H and 13C NMR spectra, the structure of complex 3 in solution is dynamic due to a rotation of the alkyne ligand. In addition, when 3 is dissolved in pyridine an easy exchange between coordinated and free molecules of pyridine takes place. In the solid state complex 3 displays a tetrahedral coordination sphere at the zirconium center composed of Cp ligands, alkyne and pyridine as shown by an X-ray structure analysis. The complex 3 reacts readily with water and carbon dioxide giving the same products as in the case of 1.

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