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YSU Jan 17th 2003

YSU Jan 17th 2003. Matthias Zeller Properties and Reactivity of Triphospholyl-Metal-Complexes. What are Triphospholyl Complexes?. YSU Jan 17th 2003. Influence on: • structure • electronic properties • reactivity etc. YSU Jan 17th 2003. What can be modified?

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YSU Jan 17th 2003

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  1. YSU Jan 17th 2003 Matthias Zeller Properties and Reactivity of Triphospholyl-Metal-Complexes

  2. What are Triphospholyl Complexes? YSU Jan 17th 2003 Influence on: • structure • electronic properties • reactivity etc

  3. YSU Jan 17th 2003 What can be modified? • Structure and Bonding Types Influence of free electron pair • Electronic Properties Degeneration of Frontier Orbitals, Sequence of Orbitals, Redox Potentials • Reactivity: Known Reactions  Reaction Rate and Products Novel Reactions  Stability and Decomposition Reactions

  4. YSU Jan 17th 2003 What was known before: J. F. Nixon et al., J. Chem. Soc., Chem. Commun.1987, 373, 1146-1148; J. Organometal. Chem.1988, 365, C1-C4; J. Organometal. Chem. 1995, 490, 155-162; J. Organometal. Chem.1989, 373, C17-C20.

  5. Our Starting Materials: YSU Jan 17th 2003 A. Elvers, F. Heinemann, B. Wrackmeyer, U. Zenneck, Chem. Eur. J. 1999, 5, 3143-3153.

  6. YSU Jan 17th 2003 Some first new Compounds: A.Elvers, T. Clark, F. W. Heinemann, M. Hennemann, M. Zeller, U. Zenneck, Angew. Chem.2000, 112, 2174-2178; A. Elvers, F. W. Heinemann, B. Wrackmeyer, U. Zenneck, Chem. Eur. J. 1999, 5, 3143-3153.

  7. YSU Jan 17th 2003 Paramagnetic 16 and 17 VE Complexes: Compare to R. Bartsch, P. B. Hitchcock, J. F. Nixon, J. Organometal. Chem. 1988, 356, C1-C4.

  8. YSU Jan 17th 2003 EPR Spectra in n-Hexane: <g> = 2.007 <A(55Mn, I=5/2)> = 78.9 G rt 120 K, glassy frozen solution g = 1.996, A~ 0 G g = 2.029, A= 115.7 G

  9. YSU Jan 17th 2003 Phosphorous in the Cp Ring  Change of Orbital Sequence

  10. YSU Jan 17th 2003 Redox Potential Shifts vs Cp2Cr the shifts are 1.7 to 2.0 V !

  11. YSU Jan 17th 2003 Reduction of ´(P3C2)2Cr´ with K/Na: EPR Spectrum in Toluene: exp. sim.

  12. YSU Jan 17th 2003 Triphospholyl Halfsandwich Complexes: Smp.: ~ -10°C

  13. YSU Jan 17th 2003 Carbonyl Substitution under mild Conditions:

  14. YSU Jan 17th 2003 Carbonyl Substitution under mild Conditions: Analogous Carbon Complex: 24 h Reflux in Hexane needed

  15. YSU Jan 17th 2003 Analogous Carbon Complex: Only Monosubstitution with CN-Cy

  16. YSU Jan 17th 2003 Carbonyl Substitution with P3-Cymantrene:

  17. YSU Jan 17th 2003

  18. YSU Jan 17th 2003 31P NMR Spectrum:

  19. YSU Jan 17th 2003 Analogous Carbon Complex: > 90 Minutes Irradiation needed for Disubstitution! Analogous Carbon Complex: No Reaction!

  20. 31P-NMR-Spectra at variable Temperatures: hindered Rotation of the Triphospholyl Ring (DH = 53 kJmol–1 ) YSU Jan 17th 2003

  21. YSU Jan 17th 2003 Enhanced Reaction Rates: Why?

  22. Triphospholyl Nickel Complexes YSU Jan 17th 2003 Compare.: But: See also: R. Bartsch, D.Carmichael, P. B. Hitchcock, M. F. Meidine, J. F. Nixon, G. J. D. Sillet, J. Chem. Soc., Chem. Commun.1988, 1615-1617.

  23. A Nickel Nitrosyl Complex: YSU Jan 17th 2003 With Cyclopentadienyl:

  24. A Reversible and Temperature Dependant --Rearrangement: YSU Jan 17th 2003 31P NMR Spectra:

  25. Trapping of the Piano Stool Complex YSU Jan 17th 2003

  26. What about Copper(I) Piano Stool Complexes? YSU Jan 17th 2003 +48°C +25°C -30°C -70°C -90°C

  27. YSU Jan 17th 2003 An Equilibrium of three Isomers?

  28. YSU Jan 17th 2003 Trapping with (OC)nW: Promotionsvortrag M. Zeller

  29. YSU Jan 17th 2003

  30. YSU Jan 17th 2003 31P NMR Spectra at variable Temperatures:

  31. 1,2-Shift or 1,5-sigmatropic Rearrangement YSU Jan 17th 2003

  32. YSU Jan 17th 2003 31P NMR Spectra at variable Temperatures:

  33. YSU Jan 17th 2003 31P NMR Coupling Constants:

  34. Is a Hexaphospha Mercurocene possible ? YSU Jan 17th 2003

  35. YSU Jan 17th 2003 A Radical Elimination Reaction ? Vergl.: A. Mack, M. Regitz, Advances in Strained and Interesting Molecules, Suppl. 11999, 199.

  36. YSU Jan 17th 2003 Under Irradition further Rearrangement occurs: Vergl.: A. Mack, M. Regitz, Advances in Strained and Interesting Molecules, Suppl. 11999, 199.

  37. YSU Jan 17th 2003 31P NMR Spectrum:

  38. YSU Jan 17th 2003 31P NMR Spectrum: Exp.: Sim.: 31P NMR Coupling Constants Y` Y X` X A` A 3.56 33.33 4.46 –86.42 63.74 X 29.55 –3.80 5.99 Y –6.74

  39. YSU Jan 17th 2003 Summary: The Inclusion of Phosphorous Atoms in coordinated -Ligands influences the properties of the complexes remarkably They show, when compared to Complexes with pure carbacyclic Ligands Change of electronic properties (hexaphospha metallocenes), novel structural properties (Ni and Cu complexes), modified reactivity (CO substitution reactions), noveldecompostion reactions (hexaphospha mercurocene)

  40. YSU Jan 17th 2003 Acknowledgements and Appreciations: Prof. Ulrich Zenneck, the Zenneck Group Dr. F. W. Heinemann (X-Ray), Dr. H. Pritzkow (X-Ray, Heidelberg), Dr. M. Moll (low temp NMR), PD Dr. W. Bauer (CP-MAS Spectra), Dr. O. Waldmann (SQUID-Measurements), Dr. G. Brehm und G. Sauer (Raman-Spectra), J. Kurzawa (UV-Vis-Spectra) Graduiertenkolleg ´Phosphorchemie als Bindeglied verschiedener Disziplinen´ ´StuSti´ (Studienstiftung des deutschen Volkes)

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