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Three photoactive Cd(II) coordination polymers (CPs), [Cd (Fsbpe)(DBBA)2]·2DMF (CP1), [Cd(Fepbpe)(DBBA)2]·2DMF (CP2) and [Cd(Fsbpeb)(DBBA)2] (CP3) (DBBA = 3,5-dibromobenzoic acid, DMF = dimethyl formamide) with similar 1D chain motifs exhibited completely different photosalient behaviors (PS) in response to UV light. Mechanical motion was triggered by [2+2] photocycloaddition and regulated by positioning of the photoactive alkene centers relative to the crystal axis. This solid-state reaction was reversed by heating and photomechanical behaviour was repeated over several cycles. A simple photoactuating device was prepared using a CP3–PVA composite. [ABSTRACT FROM AUTHOR]

Reaction of a P/N/S hybrid ligand dpppyatc (N,N‐bis((diphenylphosphaneyl)methyl)‐N‐(pyridin‐2‐yl)‐amino‐thiocarbamide) with Au(tht)Cl (tht=tetrahydrothiophene) and [Cu(MeCN)4]BF4 afforded cluster complex [Au2Cu(dpppyatc)2](BF4)2Cl (1). Upon excitation at 480 nm, 1 emitted orange phosphorescence at 646 nm, which was red‐shifted to ~698 nm selectively in the presence of ammonia or amine vapor. This chromic photoluminescent response toward ammonia was sensitive and reversible. Complex1 could detect ammonia in aqueous solution down to concentrations of 2 ppm (w/w). [ABSTRACT FROM AUTHOR]

It is well known that diazonium salts (ArN2+) react with phenols (Ar′OH) to give aryl diazoethers or diazo compounds, but their cross-coupling to exclusively access diaryl ethers is challenging. Herein we disclose the Cu-catalyzed etherification of phenols with aryl diazonium salts at room temperature, yielding diaryl ethers in moderate to excellent yields. The advantages of this protocol are mild reaction conditions, availability of reactants, operational simplicity, high tolerance of other functional groups and easy work-up. Its application to the synthesis of complex biological molecules is demonstrated. The reaction proceeds through single-electron transfer, extrusion of nitrogen, oxidative addition, and reductive elimination to give diaryl ether products. [ABSTRACT FROM AUTHOR]

Earth-abundant copper(I) coordination complexes of an imine-phosphine and a diimine have been developed as visible-light photocatalysts. Reaction of [Cu(MeCN)4]BF4 with hetero-bidentate phosphinopyrazole (phpz) ligand R1R2C3HN2PPh3 (R1 = R2 = H (1a); R1 = H, R2 = Me (1b); R1 = H, R2 = Ph (1c); R1 = R2 = Me (1d)) and 2,9-dimethyl-1,10-phenanthroline (dmp) gave four heteroleptic bis-chelate Cu(I) complexes [Cu(dmp)(R1R2C3HN2PPh3)]BF4 (R1 = R2 = H (2a); R1 = H, R2 = Me (2b); R1 = H, R2 = Ph (2c); R1 = R2 = Me (2d)) with distorted tetrahedral geometries. Complexes 2a–2d exhibited broad absorption in the visible spectrum and could facilitate photochemical intermolecular atom-transfer radical addition reactions of CBr4, or CCl3Br, CHI3 to styrenes in yields up to 91% and with a broad substrate scope. The absorption, emission, redox potential and photocatalytic activity were dependent on the substituents on the phpz ligand. Mechanistic studies supported an atom-transfer radical addition (ATRA) mechanism. [ABSTRACT FROM AUTHOR]

Coordination polymers of transition metal ions are fascinating and important to coordination chemistry. One of the ligands known to form particularly interesting coordination polymers is 3,3′,5,5′-tetramethyl-4,4′-bipyrazole (Me4bpzH2). Group 11 metal(I) ion coordination polymers, other than those of copper(I), are relatively easy to handle because of their low reactivity towards dioxygen and moisture. However, the known silver(I) coordination polymers often have poor solubility in common solvents and so cannot be easily analyzed in solution. By using a tetramethyl substituted bipyrazole ligand, we have synthesized more soluble silver(I) complexes that contain the trifluoromethyl group in the coordinated ions CF3CO2− and CF3SO3− in [Ag(CF3CO2)(Me4bpzH2)] and [Ag(CF3SO3)(Me4bpzH2)]. We determined both structures by single-crystal X-ray analysis at low temperatures and compared them in detail. Moreover, we investigated the solution behavior of these coordination polymers by 1H-NMR, IR, Raman, UV–Vis spectroscopies, and their low-temperature, solid-state photoluminescence. The high-energy band at ~330 nm corresponded to ligand-centered (bipyrazole) fluorescence, and the low-energy band at ~400 nm to ligand-centered phosphorescence resulting from the heavy atom effect. [ABSTRACT FROM AUTHOR]

The delivery of biocompatible reagents into cancer cells can elicit an anticancer effect by taking advantage of the unique characteristics of the tumor microenvironment (TME). In this work, we report that nanoscale two-dimensional FeII- and CoII-based metal–organic frameworks (NMOFs) of porphyrin ligand meso-tetrakis (6-(hydroxymethyl) pyridin-3-yl) porphyrin (THPP) can catalyze the generation of hydroxyl radicals (•OH) and O2 in the presence of H2O2 that is overexpressed in the TME. Photodynamic therapy consumes the generated O2 to produce a singlet oxygen (1O2). Both •OH and 1O2 are reactive oxygen species (ROS) that inhibit cancer cell proliferation. The FeII- and CoII-based NMOFs were non-toxic in the dark but cytotoxic when irradiated with 660 nm light. This preliminary work points to the potential of porphyrin-based ligands of transition metals as anticancer drugs by synergizing different therapeutic modalities. [ABSTRACT FROM AUTHOR]