The synthesis and structural characterization of the first sulfur-containing derivatives of C,C-biscarborane {ortho-C2B10}2 cluster – thiol, thioether, and disulfide- is reported. The biscarboranyl dithiol (1-HS-C2B10H10)2 exhibits the exceedingly long intracluster carbon-carbon bond length of 1.858(3) Å, which is attributed to the extensive interaction between lone pairs of thiol groups and the unoccupied molecular orbital of carborane cluster. The structures of doubly deprotonated biscarboranyl dithiolate anion (1-S-C2B10H10)22– with various countercations feature even longer carbon-carbon bond of 2.062(10) Å within the cluster along with the short carbon-sulfur bond of 1.660(7) Å, both indicative of significant delocalization of electron density from sulfur atoms into the cluster.
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Free Three-Dimensional Carborane Carbanions
Carbon atom functionalization via generation of carbanions is the cornerstone of carborane chemistry. In this work, we report the synthesis and structural characterization of free ortho-carboranyl [C2B10H11]−, a three-dimensional inorganic analog of the elusive phenyl anion that features a “naked” carbanion center. The first example of a stable, discrete C(H)-deprotonated carborane anion was isolated as a completely separated ion pair with a crown ether-encapsulated potassium cation. An analogous approach led to the isolation and structural characterization of a doubly deprotonated 1,1′-bis(o-carborane) anion [C2B10H10]22−, which is the first example of a discrete molecular dicarbanion. These reactive carbanions are key intermediates in carbon vertex chemistry of carborane clusters.
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- Award ID(s):
- 1654301
- NSF-PAR ID:
- 10273291
- Date Published:
- Journal Name:
- Chemical Science
- ISSN:
- 2041-6520
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D1SC02252K
