High-Valent Copper(III) Cyanide Tetramer Stabilized by Trifluoromethyl Ligands and its Multifaceted Reactivity
Year: 2026
Type: preprint
Abstract: High-valent neutral copper(III) complexes are highly elusive species with strong Lewis acidic properties and high effective nuclear charge. Herein, an unprecedented copper(III) cyanide [Cu(CF3)2(CN)]4 stabilized in a tetrameric square-like scaffold with bridging cyanide ligands was isolated and fully characterized in the form of tetrahydrate [Cu(CF3)2(CN)(H2O)]4, including X-ray crystallography. This tetrameric scaffold is stable to Lewis bases, while the apical ligands easily undergo substitution to acetonitrile and cis-trans isomerization in the presence of acetone. Lewis acidity of copper(III) cyanides – hypothetical Cu(CF3)2(CN) and a tetrameric scaffold [Cu(CF3)2(CN)]4 – was evaluated by experimental and computational methods. Relevance of the [Cu(CF3)2(CN)(solv)]4 scaffold for carbon-carbon bond formation was demonstrated by spontaneous reductive elimination of CF3CN at room temperature in high yield, and trifluoromethylation of a boronic acid.
Source: ChemRxiv
Institution: Freie Universität Berlin
Language: English
Subfield: Organic Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: green
Funder: Freie Universität Berlin
OpenAlex ID: W7223176401