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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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Cationic Complexes with Au→Ge Bonds – Synthesis and Carbophilic Reactivity
Abstract As part of our efforts to interface late transition metals with Lewis acidic main group fragments, we have decided to investigate gold complexes bearing halogermanes as Z‐type ligands. Toward this end, we have synthesized complexes of general formula [(o‐(Ph2P)C6H4)2(Ph)(X)GeAuCl] (X = F, Cl). Experimental and computational analyses indicate the presence of an Au→Ge interaction in both cases. Chloride abstraction reactions have also been investigated. In the case of X = Cl, double chloride abstraction with AgSbF6affords a putative dication that gradually abstracts fluoride from its counterion. This putative dication is also significantly more active as a catalyst than its monocationic analog in alkyne hydroamination reactions.
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- Award ID(s):
- 2154972
- PAR ID:
- 10371478
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Israel Journal of Chemistry
- Volume:
- 63
- Issue:
- 9
- ISSN:
- 0021-2148
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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