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Spying on the boron-boron triple bond using spin-spin coupling measured from ¹¹B solid-state NMR spectroscopy.

ABSTRACT: There is currently tremendous interest in the previously documented example of a stable species exhibiting a boron-boron triple bond (Science, 2012, 336, 1420). Notably, it has recently been stated using arguments based on force constants that this diboryne may not, in reality, feature a boron-boron triple bond. Here, we use advanced solid-state NMR and computational methodology in order to directly probe the orbitals involved in multiple boron-boron bonds experimentally via analysis of ¹¹B-¹¹B spin-spin (J) coupling constants. Computationally, the mechanism responsible for the boron-boron spin-spin coupling in these species is found to be analogous to that for the case of multiply-bonded carbon atoms. The trend in reduced J coupling constants for diborenes and a diboryne, measured experimentally, is in agreement with that known for alkenes and alkynes. This experimental probe of the electronic structure of the boron-boron multiple bond provides strong evidence supporting the originally proposed nature of the bonds in the diboryne and diborenes, and demonstrates that the orbitals involved in boron-boron bonding are equivalent to those well known to construct the multiple bonds between other second-row elements such as carbon and nitrogen.

SUBMITTER: Perras FA

PROVIDER: S-EPMC5657093 | biostudies-literature | 2015 Jun

REPOSITORIES: biostudies-literature

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Spying on the boron-boron triple bond using spin-spin coupling measured from 11B solid-state NMR spectroscopy.

Perras Frédéric A FA Ewing William C WC Dellermann Theresa T Böhnke Julian J Ullrich Stefan S Schäfer Thomas T Braunschweig Holger H Bryce David L DL

Chemical science 20150401 6

There is currently tremendous interest in the previously documented example of a stable species exhibiting a boron-boron triple bond (Science, 2012, 336, 1420). Notably, it has recently been stated using arguments based on force constants that this diboryne may not, in reality, feature a boron-boron triple bond. Here, we use advanced solid-state NMR and computational methodology in order to directly probe the orbitals involved in multiple boron-boron bonds experimentally via ...[more]

PMID: 29142694

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Dataset Information

Spying on the boron-boron triple bond using spin-spin coupling measured from ¹¹B solid-state NMR spectroscopy.

Publications

Spying on the boron-boron triple bond using spin-spin coupling measured from <sup>11</sup>B solid-state NMR spectroscopy.

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