Synthesis, Structure and Reactivity of Ruthenium(II) Carbonyl Complexes Containing Bis(pyrazol-1-yl)methane and Bis(N-methylimidazol-2-yl)methane

✍ Scribed by Barbara A. Messerle; Vicki-Anne Tolhurst; Peter Turner

• Publisher: John Wiley and Sons
• Year: 2003
• Tongue: English
• Weight: 174 KB
• Volume: 2003
• Category: Article
• ISSN: 1434-1948
• DOI: 10.1002/ejic.200390039

✦ Synopsis

Abstract

A series of ruthenium(II) complexes with the pyrazolylalkane ligands bis(pyrazol‐1‐yl)methane (BPM) (I) and bis(3,5‐dimethylpyrazol‐1‐yl)methane (dmBPM) (II), and the imidazolylalkane ligand bis(N‐methylimidazol‐2‐yl)methane (BIM) (III) have been synthesised and characterised. The complexes [Ru(N‐N)(CO)~2~X~2~] [N‐N = BPM, X = Cl (1a), Br (1b); N‐N = dmBPM, X = Cl (2); N‐N = BIM, X = Cl (3)] were prepared from the stoichiometric reaction of [Ru(CO)~2~X~2~]~n~ and the bidentate N‐donor ligand in refluxing methanol. The crystal structure of 2 showed the complex to have octahedral geometry about the ruthenium centre, with the carbonyl and chloride ligands being coordinated cis and trans, respectively. The complex [Ru(BPM)~2~(CO)(Cl)][BPh~4~] (4) was prepared from the reaction of RuCl~3~ and BPM in refluxing DMF, or from the decarbonylation of [Ru(BPM)(CO)~2~Cl~2~] (1a) in the presence of BPM and NaBPh~4~. The NMR spectra of 4 were fully assigned from 2D NMR experiments. The NOESY showed a cis coordination of the chloride and carbonyl ligands, and this was confirmed by single crystal X‐ray diffraction studies. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)