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Lewis Acidity of the SbCl 3 / o ‐chloranil System
Abstract While SbCl3is typically inert toward oxidation byortho‐quinones, we useo‐chloranil to show that the outcome of such reactions may be altered by the presence of a donor such as triphenylphosphine oxide, which readily traps the SbCl3(catCl) synthon (catCl = tetrachlorocatecholate) in the form of the corresponding adduct Ph3PO→SbCl3(catCl). The same reaction in the presence of a chloride salt affords the corresponding antimonate anion [Cl4Sb(catCl)]−. Computational studies indicate that the putative SbCl3(catCl) synthon has a higher chloride ion affinity than SbCl5, suggesting significant Lewis acidity. This property is further demonstrated by the use of the SbCl3/o‐chloranil system for both THF polymerization and a Friedel–Crafts‐type alkylation of benzene using 1‐fluorooctane. Finally, the reaction ofE‐stilbene witho‐chloranil in the presence of SbCl3affords the corresponding benzodioxene, suggesting that SbCl3may also operate as a redox‐active catalyst.
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- Award ID(s):
- 2316689
- PAR ID:
- 10644227
- Publisher / Repository:
- Angewandte Chemie International Edition
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 64
- Issue:
- 29
- ISSN:
- 1433-7851
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1002/anie.202505893
