Štíbr, Bohumil, Holub, Josef, Bakardjiev, Mario et al. (4 more authors) (2017) Unusual cage rearrangements in 10-vertex nido-5,6-dicarbaborane derivatives:An interplay between theory and experiment. Inorganic Chemistry. pp. 852-860. ISSN 0020-1669
Abstract
The reaction between selected X-nido-5,6-C2B8H11 compounds (where X = Cl, Br, I) and "Proton Sponge" [PS; 1,8-bis(dimethylamino)naphthalene], followed by acidification, results in extensive rearrangement of all cage vertices. Specifically, deprotonation of 7-X-5,6-C2B8H11 compounds with one equivalent of PS in hexane or CH2Cl2 at ambient temperature led to a 7 → 10 halogen rearrangement, forming a series of PSH+[10-X-5,6-C2B8H10]- salts. Reprotonation using concentrated H2SO4 in CH2Cl2 generates a series of neutral carbaboranes 10-X-5,6-C2B8H11, with the overall 7 → 10 conversion being 75%, 95%, and 100% for X = Cl, Br, and I, respectively. Under similar conditions, 4-Cl-5,6-C2B8H11 gave ∼66% conversion to 3- Cl-5,6-C2B8H11. Since these rearrangements could not be rationalized using the Bvertex swing mechanism, new cage rearrangement mechanisms, which are substantiated using DFT calculations, have been proposed. Experimental 11B NMR chemical shifts are well reproduced by the computations; as expected δ(11B) for B(10) atoms in derivatives with X = Br and I are heavily affected by spin-orbit coupling.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2016 American Chemical Society. This is an author-produced version of the published paper. Uploaded in accordance with the publisher’s self-archiving policy. Further copying may not be permitted; contact the publisher for details |
Dates: |
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Institution: | The University of York |
Academic Units: | The University of York > Faculty of Sciences (York) > Chemistry (York) |
Funding Information: | Funder Grant number EPSRC EP/I004122/2 |
Depositing User: | Pure (York) |
Date Deposited: | 23 Dec 2016 14:58 |
Last Modified: | 26 Jan 2025 00:10 |
Published Version: | https://doi.org/10.1021/acs.inorgchem.6b02320 |
Status: | Published |
Refereed: | Yes |
Identification Number: | 10.1021/acs.inorgchem.6b02320 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:109892 |