Isomerisation following the platination of [7,8-Ph2-9,11-I 2-7,8-nido-C2B9H7]2-

David Ellis, Rhona M. Garrioch, Georgina M. Rosair, Alan J. Welch

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

The synthesis, by electrophilic substitution, and characterisation of two new B-substituted nido diphenylcarboranes is described. [HNMe 3][7,8-Ph2-9-I-7,8-nido-C2B9H 9] (1) and [HNMe3][7,8-Ph2-9,11-I 2-7,8-nido-C2B9H8] (2) were characterised spectroscopically with the structure of the latter additionally confirmed by a crystallographic study. [7,8-Ph2-9,11-I 2-7,8-nido-C2B9H8]2- was treated with a source of {Pt(PMe2Ph)2}2+ and three new platinacarboranes isolated. All were characterised by a combination of 1H, 11B and 31P NMR spectroscopies and by single crystal X-ray diffraction, and all were found to have undergone a 1,2 ? 1,7 cage C atom isomerisation, relative to the presumed first product of the metallation. The major product 3 is 1,8-Ph2-2,2-(PMe 2Ph)2-6,7-I2-2,1,8-closo-PtC2B 9H7 with both (iodide) substituted boron vertices in the upper part of the icosahedron. The minor products 4 and 5 are, respectively, 1,8-Ph2-2,2-(PMe2Ph)2-6,12-I 2-2,1,8-closo-PtC2B9H7 and 1,8-Ph2-2,2-(PMe2Ph)2-10,12-I 2-2,1,8-closo-PtC2B9H7, having one and two substituted boron vertices in the lower pentagonal belt. These structural results allow speculation on the mechanism of isomerisation of crowded platinacarboranes. © 2005 Elsevier Ltd. All rights reserved.

Original languageEnglish
Pages (from-to)915-922
Number of pages8
JournalPolyhedron
Volume25
Issue number4
DOIs
Publication statusPublished - 6 Mar 2006

Keywords

  • Isomerisation mechanisms
  • Metallacarborane
  • NMR spectroscopy
  • Synthesis
  • X-ray crystallography

Fingerprint Dive into the research topics of 'Isomerisation following the platination of [7,8-Ph<sub>2</sub>-9,11-I <sub>2</sub>-7,8-nido-C<sub>2</sub>B<sub>9</sub>H<sub>7</sub>]<sup>2-</sup>'. Together they form a unique fingerprint.

Cite this