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Abstract The synthesis of tris(ortho‐carboranyl)borane (BoCb3), a single site neutral Lewis superacid, in one pot from commercially available materials is achieved. The high fluoride ion affinity (FIA) confirms its classification as a Lewis superacid and the Gutmann‐Beckett method as well as adducts with Lewis bases indicate stronger Lewis acidity over the widely used fluorinated aryl boranes. The electron withdrawing effect ofortho‐carborane and lack of pi‐delocalization of the LUMO rationalize the unusually high Lewis acidity. Catalytic studies indicate that BoCb3is a superior catalyst for promoting C−F bond functionalization reactions than tris(pentafluorophenyl)borane [B(C6F5)3].
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Developing benign syntheses using ion pairs via solvent-free mechanochemistry
Solvent-free mechanochemical conditions have been developed to investigate the significance of ion pairing and the use of weak bases for driving forward nucleophilic substitution reactions. This approach takes advantage of the lack of solvent shells to incorporate weaker and safer bases to drive reactions to completion through specific ion pairing pathways. The most efficient reactions contained larger and more polarizable cation and anion pairs.
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- Award ID(s):
- 1900097
- PAR ID:
- 10192359
- Date Published:
- Journal Name:
- Green Chemistry
- Volume:
- 22
- Issue:
- 11
- ISSN:
- 1463-9262
- Page Range / eLocation ID:
- 3638 to 3642
- 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/D0GC01116A
