Greatrex, R. and Workman, C. and Johnston, B. and Rankin, D.W.H. and Robertson, H.E. (2004) The molecular structure of pentaborane(9) with halogen substituents in apical and basal positions, determined by electron diffraction and theoretical calculations. Dalton Transactions, 11. pp. 1719-1725. ISSN 1472-7773Full text not available in this repository. (Request a copy from the Strathclyde author)
The molecular structures of 1-bromo–pentaborane(9) and 2-bromo–pentaborane(9) in the gas phase have been determined by electron diffraction and ab initio and DFT computational methods. Computational methods have also been applied to the fluoro and chloro analogues, to 1,2-dibromo-pentaborane(9), and to the parent unsubstituted borane. The electronic effects of halogen substitution on the borane cage are remarkably small, particularly for chlorine and bromine substituents, and steric effects are also minimal, even in the compound with two bromine atoms. The largest effects are (a) lengthening of B(base)–B(apex) bonds adjacent to the halogen in the 2-isomers, with an associated shortening of the opposite base–apex bond, (b) shortening of the B(base)–B(apex) bond in the 1-fluoro compound, and (c) increase of the B(base)–B(apex)–F angle in 1-F–B5H8, but a decrease in this angle in the 2-bromo compounds.
|Keywords:||pentaborane , halogen substituents , electron diffraction, Pharmacy and materia medica|
|Subjects:||Medicine > Pharmacy and materia medica|
|Department:||Faculty of Science > Strathclyde Institute of Pharmacy and Biomedical Sciences|
|Depositing user:||Pure Administrator|
|Date Deposited:||29 Feb 2012 16:10|
|Last modified:||29 Apr 2016 09:10|