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Abstract To augment the fluoride binding ability of Lewis acidic stiboranes, we have synthesized and characterized a SbVderivative (PhSbF2((o‐(NH(2,6‐C6H3F2)C6H4)2,3) featuring diarylamine groups installed in proximity to the antimony center and poised to engage Sb‐bound fluoride anions in hydrogen bonding interactions. A competition experiment between3and Ph3SbF2(4) along with calculations show that the fluoride ion affinity of3is superior to that of4.
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Fluoride Binding by a Neutral Organoantimony(V) Lewis Acid Embedded within a Dibenzodithiophene Chromophore
Organoantimony Lewis acids have been coveted for their ability to bind hard anions like fluoride in competing media. Herein, we describe the synthesis of a phenyl dithienostibole (1) in which the antimony(III) center is embedded within a planar dibenzodithiophene chromophore. Compound1reacts witho‐chloranil to form the corresponding catecholatostiborane (2); it also reacts withtert‐butyl peroxide in the presence of perfluoropinacol to form the corresponding pinacolatostiborane (3). Compound2was investigated as a platform for anion binding. UV–vis titrations in CH2Cl2afforded an association constant greater than 107 M−1pointing to the high fluoridophilicity of this new system. Density functional theory calculations highlight the role played by theσ*(Sb‐Cphenyl) orbital in imparting Lewis acidity to the antimony center of2.
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- Award ID(s):
- 2108728
- PAR ID:
- 10571481
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Zeitschrift für anorganische und allgemeine Chemie
- Volume:
- 651
- Issue:
- 2
- ISSN:
- 0044-2313
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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