Formation and characterisation of silylated supermesityl derivatives

Elisabeth Schwarz, Stefan Müller, Ana Torvisco Gomez, Michaela Flock

Research output: Contribution to conferencePosterResearchpeer-review

Abstract

In recent decades, it has generally been recognised that the role of carbenes and their analogues has become increasingly important in modern chemistry.[1] While the chemistry of carbenes has been well understood, the heavier congeners, such as silylenes, germylenes, stannylenes, and plumbylenes still need to be examined more closely.
Tetrylenes feature a great reactivity, which makes it very difficult to isolate them under ambient conditions. The instability can be decreased by interaction with Lewis-basic substituents in α,α’ – position. Thus the electrophilicity of the tetrylene can be lowered. With a cyclic backbone this effect can be increased, because the rotation of the substituents on the tetrylene is hindered. Since N-heterocyclic carbenes can be used in catalysis and as donor ligands, they are common in modern chemistry. Cyclic α,α’– phosphor stabilised derivatives are scarce in literature. It was noticed that the p-donor capabilities of the phosphorus could be as large, or larger than those of nitrogen.[2] Therefore P-heterocyclic carbenes, PHCs, would be excellent candidates to complement NHCs.[2]
Supermesityl phosphanes feature an accessible possibility and broaden the range of aromatic ligands suitable for diphosphatetrylene synthesis. Most of the known diphosphatetrylenes are dimers. The dimerisation is favoured with smaller and non-interacting substituents.
During this work the supermesityl silyl phosphane, Mes*P(H)SiMe3, and its lithium and potassium salt derivatives were used in the formation of diphosphenes.[3]
Using calculations at the level of DFT the influence of various substituents (H, Me, tBu, tBu3C, Ph, TMS, Hyp) and other suitable backbones, such as Ph, Mes, 1,1’-binaphthalene, were investigated. The theoretical information, such as conformations and spectroscopic properties of the tetrylenes are used to identify suitable candidates for synthesis and product identification.

[1] Y. Mizuhata; T.Sasamori; N.Tokitoh, N.Chem.Rev. 2009, 109 (8), 3279.
[2] D.Martin; A. Baceiredo; H. Gornitzka, Angew.Chem.Int.Ed. 2005, 44, 1700.
[3] E.Niecke; O. Altmeyer; M. Nieger, Angew.Chem. 1991, 103, 1158.
Translated title of the contributionSynthese und Charakterisierung von silierten Supermesityl Derivativen
Original languageEnglish
Publication statusPublished - 7 Mar 2016
Event13th European Workshop on Phosphorus Chemistry - Freie Universität Berlin, Berlin, Germany
Duration: 7 Mar 20169 Mar 2016

Workshop

Workshop13th European Workshop on Phosphorus Chemistry
CountryGermany
CityBerlin
Period7/03/169/03/16

ASJC Scopus subject areas

  • Chemistry(all)

Fields of Expertise

  • Advanced Materials Science

Cooperations

  • NAWI Graz

Cite this

Schwarz, E., Müller, S., Torvisco Gomez, A., & Flock, M. (2016). Formation and characterisation of silylated supermesityl derivatives. Poster session presented at 13th European Workshop on Phosphorus Chemistry, Berlin, Germany.