690635-94-0Relevant academic research and scientific papers
Complexes of heteroscorpionate trispyrazolylborate ligands. Part XII. Variable hapticity of hydrobis(3-phenyl-5-isopropylpyrazolyl)(3,5- dimethylpyrazolyl)borate in its rhodium(I) complexes with COD and NBD
Ruman, Tomasz,Ciunik, Zbigniew,Wo?owiec, Stanis?aw
, p. 219 - 223 (2004)
The structure of Tp″Rh(NBD) complex was determined by X-ray crystallography (Tp″=hydrobis(3-phenyl-5-isopropylpyrazolyl)(3,5- dimethylpyrazolyl)borate, NBD=2,5-norbornadiene). The Tp″ was found to be κ3 coordinated to rhodium(I). Two independent molecules of Tp″Rh(NBD) were found in triclinic crystals with Rh-N(pz) distances in the region of 2.113(3)-2.307(3) A?. On the other hand the same Tp″ ligand was demonstrated to be coordinated in κ2 fashion in Tp″Rh(COD) (COD=1,5-cyclooctadiene) by variable temperature 1-D and 2-D 1H NMR measurements. The intramolecular exchange between coordinated and uncoordinated 3-phenyl-5-isopropylpyrazolyl residues occurs with ΔG≠=42.2 kJ/mol as it was calculated from the 1H NMR studies.
