Chapter 39. Iodo Trimethylsilylmethylene Triphenylphosphorane — a Molecule of Theoretical and Synthetic Interest

  1. Prof. Norbert Auner2 and
  2. Prof. Johann Weis3
  1. K. Korth,
  2. A. Schorm,
  3. J. Sundermeyer,
  4. H. Hermann and
  5. G. Boche

Published Online: 28 APR 2008

DOI: 10.1002/9783527619917.ch39

Organosilicon Chemistry IV: From Molecules to Materials

Organosilicon Chemistry IV: From Molecules to Materials

How to Cite

Korth, K., Schorm, A., Sundermeyer, J., Hermann, H. and Boche, G. (2000) Iodo Trimethylsilylmethylene Triphenylphosphorane — a Molecule of Theoretical and Synthetic Interest, in Organosilicon Chemistry IV: From Molecules to Materials (eds N. Auner and J. Weis), Wiley-VCH Verlag GmbH, Weinheim, Germany. doi: 10.1002/9783527619917.ch39

Editor Information

  1. 2

    Inst. für Anorganische Chemie, der Universität Frankfurt, Marie-Curie-Strasse 11, D-60439 Frankfurt am Main, Germany, Phone: 0 69/7 98-29180, -29591, Fax: 069/798-29188

  2. 3

    Wacker-Chemie GmbH, Geschäftsbereich S, Werk Burghausen, Johannes-Hess-Strasse 24, D-84489 Burghausen, Germany

Author Information

  1. Fachbereich Chemie, Philipps - Universität Marburg Hans-Meenvein-Straße, D-35032 Marburg/Lahn, Germany

Publication History

  1. Published Online: 28 APR 2008
  2. Published Print: 17 JAN 2000

ISBN Information

Print ISBN: 9783527298549

Online ISBN: 9783527619917

SEARCH

Keywords:

  • carbanion stabilization;
  • phosphorus ylides;
  • structure determinations;
  • silyl group effects

Summary

In phosphorus ylides such as iodo trimethylsilylmethylene triphenylphosphorane all the carbon substituents (iodine, SiMe3, PPh3+) are involved in carbanion stabilization. The aim of this work was to elucidate the competition of the carbon ligands in stabilizing the carbanion center. For that reason we synthesized the compounds Ph3P[DOUBLE BOND]C(I)SiMe3 1, Ph3P[DOUBLE BOND]C(I)H 2 and Ph3P[DOUBLE BOND]C(H)SiMe3 3 in which the substituents (H, I, SiMe3) at the ylidic carbon are systematically interchanged. As a result of our combined solid-state and quantum-chemical studies we found that hyperconjugative stabilization between the ylidic carbon and the phosphonium group is less significant due to the effect of other electron-withdrawing ligands. In particular, the stabilization effect of iodine was found to be of greater influence than expected.