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Metal-ligand cooperation is an important aspect in earth-abundant metal catalysis. Utilizing ligands as electron reservoirs to supplement the redox chemistry of the metal has resulted in many new exciting discoveries. Here, we demonstrate that iron bipyridine-diimine (BDI) complexes exhibit an extensive electron-transfer series that spans a total of five oxidation states, ranging from the trication [Fe(BDI)]3+ to the monoanion [Fe(BDI]-1. Structural characterization by X-ray crystallography revealed the multifaceted redox noninnocence of the BDI ligand, while spectroscopic (e.g., 57Fe Mössbauer and EPR spectroscopy) and computational studies were employed to elucidate the electronic structure of the isolated complexes, which are further discussed in this report.

Considering the potential advantages of minimally sized corroles for diverse applications, this study reports a facile access to cyano‐substituted derivatives via a rare CF3/CN conversion. Investigation of the fully characterized gallium, phosphorus, and cobalt complexes discloses multiple effects of the meso‐nitrile groups attached to the macrocycle. This corrole appears to be the most electron poor derivative which comes into play in the redox potentials of the corresponding complexes. Compared to its precursor, both the absorption and emission are strongly red shifted and the fluorescence lifetime and quantum yield are much larger. The coordination chemistry is affected as well, by virtue of axial ligands being perpendicular rather than parallel relative to each other. [ABSTRACT FROM AUTHOR]

In cold methanol, energetic ionic liquid 1-n-propyl-3-vinyl-imidazol-1-ium perchlorate, 1, crystallizes in the presence of excess Ba(ClO4)2, 2, into tetrakis 1-propyl-3-vinyl-imidazol-1-ium·barium hexa-perchlorate, 3. Crystals of 3, with molecular formula (C8H13N2)4·BaCl6O24, are colorless and monoclinic, with space group P21/c. The crystal structure is characterized by a dodecahedral coordination around the barium atom, with each perchlorate chelating Ba2+ in a κ2O,O' fashion, and the Ba(ClO4)64− anion is surrounded by four imidazolium cations. [ABSTRACT FROM AUTHOR]

Boron subphthalocyanines with chloride and fluoride axial ligands and three antimony complexes chelated by corroles that differ in size and electron‐richness were examined as electrocatalysts for reduction of protons to hydrogen. Experiment‐ and computation‐based investigations revealed that all redox events are ligand‐centered and that the meso‐C of the corroles and the peripheral N atoms of the subphthalocyanines are the largely preferred proton‐binding sites. [ABSTRACT FROM AUTHOR]

Construction of functional synthetic systems that can reversibly bind and transport the most biologically important gaseous molecules, oxygen and nitric oxide (NO), remains a contemporary challenge. Myoglobin and nitrophorin perform these respective tasks employing a protein‐embedded heme center where one axial iron site is occupied by a histidine residue and the other is available for small molecule ligation, structural features that are extremely difficult to mimic in protein‐free environments. Indeed, the hitherto reported designs rely on sophisticated multistep syntheses for limiting access to one of the two axial coordination sites in small molecules. We have shown previously that binuclear Ga(III) and Al(III) corroles have available axial sites, and now report a redox‐active binuclear Fe(III) corrole, (1‐Fe)2, in which each (corrolato)Fe(III) center is 5‐coordinate, with one axial site occupied by an imidazole from the other corrole. The binuclear structure is further stabilized by attractive forces between the corrole π systems. Reaction of NO with (1‐Fe)2 affords mononuclear iron nitrosyls, and of functional relevance, the reaction is reversible: nitric oxide is released upon purging the nitrosyls with inert gases, thereby restoring (1‐Fe)2 in solutions or films. [ABSTRACT FROM AUTHOR]

'Prevention is better than cure, especially when something has no cure.' Cancer, in most patients is detected at the stage beyond which it becomes noncurative. Therefore, the early detection of cancer cells can play a crucial role in enhancing the chances of a patient's survival. In this light, we present a nonfluorescent receptor used for the detection of Zn2+ ion in MDA‐MB‐231 carcinoma cells that exhibits fluorescence turn‐on behaviour upon binding with the metal ion. In this work, the synthesis of 11,16‐bis(2,6‐difluorobenzene)‐6,6,21,21‐tetramethyl‐meta‐benziporpho‐6,21‐dimethene and its Zn2+ chloride complex have been reported. The compounds were fully characterized using UV–visible, nuclear magnetic resonance (NMR), infrared (IR) and mass spectrometry. Furthermore, the X‐ray polymorphs of a meta‐benziporphodimethene analogue were added. The study of its bioimaging applications in MDA‐MB‐231 breast cancer cells for the detection of Zn2+ ions is reported. [ABSTRACT FROM AUTHOR]