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Characterizing Lewis Pairs Using Titration Coupled with In Situ Infrared Spectroscopy
Published on: February 20, 2020
Unlocking Lewis acidity via the redox non-innocence of a phenothiazine-substituted borane
Taylor P L Cosby1, Avik Bhattacharjee1, Samantha K Henneberry1
1Department of Chemistry, York University, 4700 Keele Street, Toronto, ON, M3J 1P3, Canada. caputo@yorku.ca.
Abstract:
We describe a new approach to enhancing Lewis acidity, through the single electron oxidation of a borane with a pendant phenothiazine. This results in the formation of a persistent radical cation with increased electrophilicity. Computational and experimental studies indicate this radical cation significantly enhances the Lewis acidity and catalytic activity compared to its neutral analog. These results illustrate the viability of this approach in turning on the Lewis acidity of relatively inert boranes.
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