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Symmetry-Amplified J Splittings for Quadrupolar Spin Pairs: A Solid-State NMR Probe of Homoatomic Covalent Bonds

[Image: see text] Chemically informative J couplings between pairs of quadrupolar nuclei in dimetallic and dimetalloid coordination motifs are measured using J-resolved solid-state NMR experiments. It is shown that the application of a double-quantum filter is necessary to observe the J splittings a...

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Autores principales: Perras, Frédéric A., Bryce, David L.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: American Chemical Society 2013
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3762131/
https://www.ncbi.nlm.nih.gov/pubmed/23919916
http://dx.doi.org/10.1021/ja407138b
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author Perras, Frédéric A.
Bryce, David L.
author_facet Perras, Frédéric A.
Bryce, David L.
author_sort Perras, Frédéric A.
collection PubMed
description [Image: see text] Chemically informative J couplings between pairs of quadrupolar nuclei in dimetallic and dimetalloid coordination motifs are measured using J-resolved solid-state NMR experiments. It is shown that the application of a double-quantum filter is necessary to observe the J splittings and that, under these conditions, only a simple doublet is expected. Interestingly, the splitting is amplified if the spins are magnetically equivalent, making it possible to measure highly precise J couplings and unambiguously probe the symmetry of the molecule. This is demonstrated experimentally by chemically breaking the symmetry about a pair of boron spins by reaction with an N-heterocyclic carbene to form a β-borylation reagent. The results show that the J coupling is a sensitive probe of bonding in diboron compounds and that the J values quantify the weakening of the B–B bond which occurs when forming an sp(2)–sp(3) diboron compound, which is relevant to their reactivity. Due to the prevalence of quadrupolar nuclei among transition metals, this work also provides a new approach to probe metal–metal bonding; results for Mn(2)(CO)(10) are provided as an example.
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spelling pubmed-37621312013-09-04 Symmetry-Amplified J Splittings for Quadrupolar Spin Pairs: A Solid-State NMR Probe of Homoatomic Covalent Bonds Perras, Frédéric A. Bryce, David L. J Am Chem Soc [Image: see text] Chemically informative J couplings between pairs of quadrupolar nuclei in dimetallic and dimetalloid coordination motifs are measured using J-resolved solid-state NMR experiments. It is shown that the application of a double-quantum filter is necessary to observe the J splittings and that, under these conditions, only a simple doublet is expected. Interestingly, the splitting is amplified if the spins are magnetically equivalent, making it possible to measure highly precise J couplings and unambiguously probe the symmetry of the molecule. This is demonstrated experimentally by chemically breaking the symmetry about a pair of boron spins by reaction with an N-heterocyclic carbene to form a β-borylation reagent. The results show that the J coupling is a sensitive probe of bonding in diboron compounds and that the J values quantify the weakening of the B–B bond which occurs when forming an sp(2)–sp(3) diboron compound, which is relevant to their reactivity. Due to the prevalence of quadrupolar nuclei among transition metals, this work also provides a new approach to probe metal–metal bonding; results for Mn(2)(CO)(10) are provided as an example. American Chemical Society 2013-08-07 2013-08-28 /pmc/articles/PMC3762131/ /pubmed/23919916 http://dx.doi.org/10.1021/ja407138b Text en Copyright © 2013 American Chemical Society Terms of Use (http://pubs.acs.org/page/policy/authorchoice_termsofuse.html)
spellingShingle Perras, Frédéric A.
Bryce, David L.
Symmetry-Amplified J Splittings for Quadrupolar Spin Pairs: A Solid-State NMR Probe of Homoatomic Covalent Bonds
title Symmetry-Amplified J Splittings for Quadrupolar Spin Pairs: A Solid-State NMR Probe of Homoatomic Covalent Bonds
title_full Symmetry-Amplified J Splittings for Quadrupolar Spin Pairs: A Solid-State NMR Probe of Homoatomic Covalent Bonds
title_fullStr Symmetry-Amplified J Splittings for Quadrupolar Spin Pairs: A Solid-State NMR Probe of Homoatomic Covalent Bonds
title_full_unstemmed Symmetry-Amplified J Splittings for Quadrupolar Spin Pairs: A Solid-State NMR Probe of Homoatomic Covalent Bonds
title_short Symmetry-Amplified J Splittings for Quadrupolar Spin Pairs: A Solid-State NMR Probe of Homoatomic Covalent Bonds
title_sort symmetry-amplified j splittings for quadrupolar spin pairs: a solid-state nmr probe of homoatomic covalent bonds
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3762131/
https://www.ncbi.nlm.nih.gov/pubmed/23919916
http://dx.doi.org/10.1021/ja407138b
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