English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
  Unusual Bonding and Properties in Main Group Element Chemistry: Rational Synthesis, Characterization, and Experimental Electron Density Determination of Mixed-Valent Tetraphosphetes

Breuers, V., Lehmann, C. W., & Frank, W. (2015). Unusual Bonding and Properties in Main Group Element Chemistry: Rational Synthesis, Characterization, and Experimental Electron Density Determination of Mixed-Valent Tetraphosphetes. Chemistry – A European Journal, 21(12), 4596-4606. doi:10.1002/chem.201406131.

Item is

Files

show Files

Locators

show

Creators

show
hide
 Creators:
Breuers, Verena1, Author
Lehmann, Christian W.2, Author              
Frank, Walter1, Author
Affiliations:
1Institut für Anorganische Chemie und Strukturchemie, Lehrstuhl II: Material- und Strukturforschung, Heinrich-Heine-Universität Düsseldorf , Universitätsstraße 1, 40225 Düsseldorf (Germany), ou_persistent22              
2Service Department Lehmann (EMR), Max-Planck-Institut für Kohlenforschung, Max Planck Society, ou_1445625              

Content

show
hide
Free keywords: circular dichroism; experimental electron density; phosphetes; phosphorus heterocycles; silicon
 Abstract: Five dispirocyclic λ35-tetraphosphetes [{R2Si(NR1)(NR2)P2}2] (R1 = R2 and R1 ≠ R2) are easily prepared in almost quantitative yields via photolysis of the respective bis(trimethylsilyl)phosphanyldiazaphosphasiletidines with intense visible light. These deep-yellow low-coordinate phosphorus compounds can be considered as the first higher congeners of the well-known cyclodiphosphazenes. The tetraphosphetes are remarkably stable in air and show unexpected molecular properties related to the unique bonding situation of the central four-π-electron four-membered phosphorus ring. The extent of rhombic distortion of the central P4 ring is remarkable due to an unusually acute angle at the σ2-phosphorus atoms. All of the PP bonds are approximately equal in length. The distances are in the middle of the range given by phosphorus single and double bonds. The anisotropic absorption of visible light that can easily be observed in the case of the yellow/colorless dichroic crystals of [{Me2Si(NtBu)(NtBu)P2}2}] and the exceptional 31P NMR chemical shift of the σ2-phosphorus atoms are the most remarkable features of the λ35-tetraphosphetes. In the case of [{Me2Si(NtBu)(NtBu)P2}2], the Hansen–Coppens multipole model is applied to extract the electron density from high-resolution X-ray diffraction data obtained at 100 K. Static deformation density and topological analysis reveal a unique bonding situation in the central unsaturated P4 fragment characterized by polar σ-bonding, pronounced out-of-ring non-bonding lone pair density on the σ2-phosphorus atoms, and an additional non-classical three-center back-bonding contribution.

Details

show
hide
Language(s): eng - English
 Dates: 2014-11-182015-02-202015-03-16
 Publication Status: Published in print
 Pages: 11
 Publishing info: -
 Table of Contents: -
 Rev. Type: Peer
 Identifiers: DOI: 10.1002/chem.201406131
 Degree: -

Event

show

Legal Case

show

Project information

show

Source 1

show
hide
Title: Chemistry – A European Journal
  Other : Chem. – Eur. J.
  Other : Chem. Eur. J.
Source Genre: Journal
 Creator(s):
Affiliations:
Publ. Info: Weinheim, Germany : VCH Verlagsgesellschaft
Pages: - Volume / Issue: 21 (12) Sequence Number: - Start / End Page: 4596 - 4606 Identifier: ISSN: 0947-6539
CoNE: https://pure.mpg.de/cone/journals/resource/954926979058