Ten-Vertex Polyhedral Rhodadicarbaborane Chemistry. Molecular Structure, NMR Properties, and Cluster Dynamic Behaviour of [2,2,2-(PPh3)2H-closo-2,1,6-RhC2B7H9]

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Title:Ten-Vertex Polyhedral Rhodadicarbaborane Chemistry. Molecular Structure, NMR Properties, and Cluster Dynamic Behaviour of [2,2,2-(PPh3)2H-closo-2,1,6-RhC2B7H9]
Creators:
Nestor, Karl
Murphy, Michael
Štíbr, Bohumil
Spalding, Trevor R.
Fontaine, Xavier L. R.
Thornton-Pett, Mark
Kennedy, John D.
Journal or Publication Title:
Collection of Czechoslovak Chemical Communications, 58, 7, pp. 1555-1568

Abstract

The compound previously described as [6,6,6-(PPh<sub>3</sub>)<sub>2</sub>H-<i>closo</i>-6,3,3-RhC<sub>2</sub>B<sub>7</sub>H<sub>9</sub>] is shown by detailed multielement NMR studies and single-crystal X-ray diffraction analysis to be its isomer [2,2,2-(PPh<sub>3</sub>)<sub>2</sub>H-<i>closo</i>-2,1,6-RhC<sub>2</sub>B<sub>7</sub>H<sub>9</sub>] Crystals (from pentane-diethyl ether) were monoclinic, space group <i>P2</i><sub>1</sub>/<i>n</i>, with <i>Z</i> = 4, and with <i>a</i> = 1 222.2(1) pm, <i>b</i> = 1 598.7(2) pm, <i>c</i> = 1 836.7(1) pm, and β = 91.86(1)°. The structure was refined to <i>R</i>(<i>R</i><sub>w</sub>) 0.0295(0.0414)using 6 819 observed data [<i>I</i> &gt; 2.0 σ(<i>I</i>)] out of 8 541 collected at 200 K. The {RhC<sub>2</sub>B<sub>7</sub>} cluster structure is to a first approximation classically <i>closo</i>, with the metal and two carbon atoms in adjacent 2, 1, and 6 positions, respectively. Both enantiomers exist in the unit cell, and variable temperature NMR studies show that the molecule is fluxional (∆<i>G</i><sub>355</sub> ≈ 60 kJ mol<sup>-1</sup>) between enantiomers via a diamond-square diamond cluster rearrangement.

Title:Ten-Vertex Polyhedral Rhodadicarbaborane Chemistry. Molecular Structure, NMR Properties, and Cluster Dynamic Behaviour of [2,2,2-(PPh3)2H-closo-2,1,6-RhC2B7H9]
Creators:
Nestor, Karl
Murphy, Michael
Štíbr, Bohumil
Spalding, Trevor R.
Fontaine, Xavier L. R.
Thornton-Pett, Mark
Kennedy, John D.
Divisions:Life and Chemical Sciences > Institute of Organic Chemistry and Biochemistry > Collection of Czechoslovak Chemical Communications
Journal or Publication Title:Collection of Czechoslovak Chemical Communications
Volume:58
Number:7
Page Range:pp. 1555-1568
ISSN:0010-0765
E-ISSN:1212-6950
Publisher:Institute of Organic Chemistry and Biochemistry
Related URLs:
URLURL Type
http://dx.doi.org/10.1135/cccc19931555UNSPECIFIED
ID Code:275
Item Type:Article
Deposited On:06 Feb 2009 16:59
Last Modified:06 Feb 2009 15:59

Citation

Nestor, Karl; Murphy, Michael; Štíbr, Bohumil; Spalding, Trevor R.; Fontaine, Xavier L. R.; Thornton-Pett, Mark; Kennedy, John D. (1993) Ten-Vertex Polyhedral Rhodadicarbaborane Chemistry. Molecular Structure, NMR Properties, and Cluster Dynamic Behaviour of [2,2,2-(PPh3)2H-closo-2,1,6-RhC2B7H9]. Collection of Czechoslovak Chemical Communications, 58 (7). pp. 1555-1568. ISSN 0010-0765

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