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Abstract Metalation of the polynucleating ligand^F,tbsLH₆(1,3,5‐C₆H₉(NC₆H₃−4‐F−2‐NSiMe₂^tBu)₃) with two equivalents of Zn(N(SiMe₃)₂)₂affords the dinuclear product (^F,tbsLH₂)Zn₂(1), which can be further deprotonated to yield (^F,tbsL)Zn₂Li₂(OEt₂)₄(2). Transmetalation of2with NiCl₂(py)₂yields the heterometallic, trinuclear cluster (^F,tbsL)Zn₂Ni(py) (3). Reduction of3with KC₈affords [KC₂₂₂][(^F,tbsL)Zn₂Ni] (4) which features a monovalent Ni centre. Addition of 1‐adamantyl azide to4generates the bridging μ³‐nitrenoid adduct [K(THF)₃][(^F,tbsL)Zn₂Ni(μ³‐NAd)] (5). EPR spectroscopy reveals that the anionic cluster possesses a doublet ground state (S=). Cyclic voltammetry of5reveals two fully reversible redox events. The dianionic nitrenoid [K₂(THF)₉][(^F,tbsL)Zn₂Ni(μ³‐NAd)] (6) was isolated and characterized while the neutral redox isomer was observed to undergo both intra‐ and intermolecular H‐atom abstraction processes. Ni K‐edge XAS studies suggest a divalent oxidation state for the Ni centres in both the monoanionic and dianionic [Zn₂Ni] nitrenoid complexes. However, DFT analysis suggests Ni‐borne oxidation for5. 

Metal atom lability from a well-defined bimetallic cluster was canvassed as a function of ligand substitution, redox chemistry, and group transfer processes. 

We report the design conception, chemical synthesis, and microbiological evaluation of the bridged macrobicyclic antibiotic cresomycin (CRM), which overcomes evolutionarily diverse forms of antimicrobial resistance that render modern antibiotics ineffective. CRM exhibits in vitro and in vivo efficacy against both Gram-positive and Gram-negative bacteria, including multidrug-resistant strains ofStaphylococcus aureus,Escherichia coli, andPseudomonas aeruginosa. We show that CRM is highly preorganized for ribosomal binding by determining its density functional theory–calculated, solution-state, solid-state, and (wild-type) ribosome-bound structures, which all align identically within the macrobicyclic subunits. Lastly, we report two additional x-ray crystal structures of CRM in complex with bacterial ribosomes separately modified by the ribosomal RNA methylases, chloramphenicol-florfenicol resistance (Cfr) and erythromycin-resistance ribosomal RNA methylase (Erm), revealing concessive adjustments by the target and antibiotic that permit CRM to maintain binding where other antibiotics fail. 

Molecular Ag(II) complexes are superoxidizing photoredox catalysts capable of generating radicals from redox-reticent substrates. In this work, we exploited the electrophilicity of Ag(II) centers in [Ag(bpy)₂(TFA)][OTf] and Ag(bpy)(TFA)₂(bpy, 2,2′-bipyridine; OTf, CF₃SO₃^–) complexes to activate trifluoroacetate (TFA) by visible light–induced homolysis. The resulting trifluoromethyl radicals may react with a variety of arenes to forge C(sp²)–CF₃bonds. This methodology is general and extends to other perfluoroalkyl carboxylates of higher chain length (R_FCO₂^–; R_F, CF₂CF₃or CF₂CF₂CF₃). The photoredox reaction may be rendered electrophotocatalytic by regenerating the Ag(II) complexes electrochemically during irradiation. Electrophotocatalytic perfluoroalkylation of arenes at turnover numbers exceeding 20 was accomplished by photoexciting the Ag(II)–TFA ligand-to-metal charge transfer (LMCT) state, followed by electrochemical reoxidation of the Ag(I) photoproduct back to the Ag(II) photoreactant. 

Atomically precise nanoclusters (NCs) provide useful model systems for studying fundamental aspects of the metal-catalysed CO₂reduction reaction (CO₂RR).