Structural characterization of the head-to-head isomers of the [Pd 2(Ph 2Ppy) 2Cl 2] and [PtPd(Ph 2Ppy) 2I 2] complexes (Ph 2Ppy = 2-(diphenylphosphino)pyridine)
The HH-[Pd 2(Ph 2Ppy) 2Cl 2] and HH-[PtPd(Ph 2Ppy) 2I 2] complexes have been characterized by X-ray crystallography. 31P MAS NMR spectroscopy has proved to be a viable method for recognizing head-to-head and head-to-tail isomers. The molecular structures of the thermodynamically unstable head-to-hea...
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Published in | Inorganica Chimica Acta Vol. 359; no. 9; pp. 2933 - 2941 |
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Main Authors | , , |
Format | Journal Article |
Language | English |
Published |
Elsevier B.V
01.06.2006
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Subjects | |
Online Access | Get full text |
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Summary: | The
HH-[Pd
2(Ph
2Ppy)
2Cl
2] and
HH-[PtPd(Ph
2Ppy)
2I
2] complexes have been characterized by X-ray crystallography.
31P MAS NMR spectroscopy has proved to be a viable method for recognizing head-to-head and head-to-tail isomers.
The molecular structures of the thermodynamically unstable head-to-head isomers,
HH-[Pd
2(Ph
2Ppy)
2Cl
2] and
HH-[PtPd(Ph
2Ppy)
2I
2], have been determined by single crystal X-ray diffraction. The two complexes have proved to be isostructural. The severe distortions of the bond angles from the ideal square planar geometry around the metal centers ligating the
trans phosphorus donor atoms are indicative of a more pronounced internal strain in the
HH isomers as compared to the
HT counterparts. The enhanced internal strain is thought to be the major driving force responsible for the spontaneous conversion of the head-to-head isomers to their head-to-tail congeners.
13C NMR spectra in solution phase as well as solid-state
31P MAS NMR spectra have proved to be informative regarding the orientation of the asymmetric Ph
2Ppy ligands. |
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ISSN: | 0020-1693 1873-3255 |
DOI: | 10.1016/j.ica.2005.12.021 |