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In the crystal of the title compound, C 6 H 6 F 8 O 4 , O—H...O hydrogen bonds involving the hydroxy groups connect the molecules, forming a two-dimensional network parallel to (100). These hydrogen-bonding interactions appear to drive the O—C—C—O torsion angles into a gauche – trans – trans series of conformations along the backbone of the molecule. 

Ten new ruthenium compounds based on the N,N,N,N-chelate Me2bpbMe2 (bpb = 1,2-bis(pyridine-2-carboximido)benzene) have prepared and characterized by 1H NMR and IR spectroscopy. The monocarbonyl compound (Me2bpbMe2)Ru(CO)(H2O) compound was generated from the reaction of the free base Me2bpbMe2H2 with Ru3(CO)12 in refluxing DMF. Isoamyl nitrite reacts with this compound to yield the trans-addition nitrosyl alkoxide (Me2bpbMe2)Ru(NO)(O-i-C5H11). Nitrosothiols similarly add in a formal trans-addition manner to yield (Me2bpbMe2)Ru(NO)(SR/Ar) (SR/Ar = S-i-C5H11, SPh, SC6F4H, SC(Me)2CHNHC(O)Me) derivatives. The (Me2bpbMe2)Ru(NO)(O-i-C5H11) compound undergoes alkoxide exchange reactions with PhOH and HOC6F4H to generate (Me2bpbMe2)Ru(NO)(OPh) and (Me2bpbMe2)Ru(NO)(OC6F4H), respectively. The neutral alkoxide/aryloxide nitrosyl compounds exhibit higher NO bands (1809–1842 cm-1) relative to their thiolate analogues (1755–1823 cm-1). The X-ray crystal structures of (Me2bpbMe2)Ru(NO)(OPh), (Me2bpbMe2)Ru(NO)(OC6F4H), and (Me2bpbMe2)Ru(NO)(SPh), have been determined, and reveal linear axial (O)N–Ru–O/S linkages consistent with trans positioning of the NO and aryloxide and -thiolate groups, and near-linear Ru–N–O moieties (164–174°) consistent with these complexes being formulated as {RuNO}6 species. The electrooxidation behavior of (Me2bpbMe2)Ru(NO)(OC6F4H), (Me2bpbMe2)Ru(NO)(SC6F4H), and (Me2bpbMe2)Ru(NO)(SPh) were examined by cyclic voltammetry and IR spectroelectrochemistry in CH2Cl2. (Me2bpbMe2)Ru(NO)(OC6F4H) and (Me2bpbMe2)Ru(NO)(SC6F4H) display reversible first oxidations, whereas (Me2bpbMe2)Ru(NO)(SPh) displays an irreversible first oxidation with likely loss of the thiolate ligand. Chemical reactivity of (Me2bpbMe2)Ru(NO)(SPh) with H+ and Me+ results in the generation of the free thiol PhSH and thioether PhSMe, respectively. 

Abstract Some bacterial heme proteins catalyze the coupling of two NO molecules to generate N₂O. We previously reported that a heme Fe–NO model engages in this N−N bond‐forming reaction with NO. We now demonstrate that (OEP)Co^II(NO) similarly reacts with 1 equiv of NO in the presence of the Lewis acids BX₃(X=F, C₆F₅) to generate N₂O. DFT calculations support retention of the Co^IIoxidation state for the experimentally observed adduct (OEP)Co^II(NO⋅BF₃), the presumed hyponitrite intermediate (P^.+)Co^II(ONNO⋅BF₃), and the porphyrin π‐radical cation by‐product of this reaction, and that the π‐radical cation formation likely occurs at the hyponitrite stage. In contrast, the Fe analogue undergoes a ferrous‐to‐ferric oxidation state conversion during this reaction. Our work shows that cobalt hemes are chemically competent to engage in the NO‐to‐N₂O conversion reaction. 

Abstract All‐inorganic metal halides such as Cs₄PbX₆and CsPbX₃(X = Cl, Br, and I) are attracting global attention owing to their promise in optoelectronic applications. However, the presence of the toxic heavy metal lead (Pb) in these materials is a major concern. Here, a family of nontoxic high‐efficiency blue‐emitting all‐inorganic halides Rb₂CuX₃(X = Br and Cl) is reported; the compounds exhibit 1D crystal structures featuring anionic²⁻ribbons separated by Rb⁺cations. The measured record high photoluminescence quantum yield values range from 64% to 100% for Rb₂CuBr₃and Rb₂CuCl₃, respectively. Furthermore, the measured emission linewidths are quite narrow with full width at half maximum values of 54 and 52 nm for Rb₂CuBr₃and Rb₂CuCl₃, respectively. Single crystals of Rb₂CuCl₃demonstrate an anti‐Stokes photoluminescence signal, shown for the first time for Pb‐free metal halides. The discovery of highly efficient narrow blue emitters based on a nontoxic and inexpensive metal copper paves a way for the consideration of low‐cost and environmentally friendly copper halides for practical applications.