Trinuclear nickel and cobalt complexes containing unsymmetrical tripodal tetradentate ligands: syntheses, structural, magnetic, and catalytic properties

A dinuclear Co(iii)/Co(ii) complex based on the H2pmide ligand showing field-induced SMM behaviour

We report a combined computational and experimental study of the field-induced SMM behaviour of a Co(ii)/Co(iii) dinuclear complex with a pair-like H-bond intermolecular interaction.

Air oxidation-induced single-crystal-to-single-crystal transformation of mixed-valence tetranuclear Fe(II)-Fe(III) complexes

A mixed valence tetranuclear iron complex [(Hpmide)Fe^II(NCSe)₂Fe^III(pmide)]₂·5CH₃OH (1) underwent oxidation and ligand exchange in the solid state (H₂pmide = N-(2-pyridylmethyl)iminodiethanol). Upon air oxidation, 1 was converted into [(pmide)Fe^III(NCSe)Fe^III(pmide)]₂(NCSe)₂·2H₂O (2), which was accompanied by deprotonation and ligand exchange through a single crystal-to-single-crystal transformation.

Activity-Based Sensing of Ascorbate by Using Copper-Mediated Oxidative Bond Cleavage

Ascorbate is an important biological reductant and enzyme cofactor. Although direct detection through ascorbate-mediated reduction is possible, this approach suffers from poor selectivity due to the wide range of cellular reducing agents. To overcome this limitation, we leverage reduction potential of ascorbate to mediate a copper-mediated oxidative bond cleavage of ether-caged fluorophores. The copper(II) complexes supported by a {bis(2-pyridylmethyl)}benzylamine or a {bis(2-pyridylmethyl)}(2-methoxybenzyl)amine ligand were identified as an ascorbate responsive unit and their reaction with ascorbate yields a copper-based oxidant that enables rapid benzylic oxidation and the release of an ether-caged dye (coumarin or fluorescein). The copper-mediated bond cleavage is specific to ascorbate and the trigger can be readily derivatized for tuning photophysical properties of the probes. The probes were successfully applied for the fluorometric detection of ascorbate in commercial food samples, human plasma, and serum, and within live cells by using confocal microscopy and flow cytometry.

Structural diversity, magnetic properties, and luminescence sensing based Ni(ii)/Zn(ii) coordination polymers of the semirigid 3,3′-((5-carboxy-1,3-phenylene)bis(oxy))dibenzate ligand

Four novel CPs were synthesized and two Zn(ii)-CPs can be used as fluorescent probes for the detection of CrO₄²⁻/Cr₂O₇²⁻.

Dinuclear cobalt complexes supported by biphenol and binaphthol-derived bis(salicylaldimine) ligands: synthesis, characterization and catalytic application in β-enaminone synthesis from 1,3-dicarbonyl compounds and aliphatic amines

Biaryl scaffolding ligands form dicobalt clusters, which serve as efficient catalysts in enaminone synthesis under ambient conditions.

Crystal structure of {2-methyl-2-[(pyridin-2-yl-meth-yl)amino]-propan-1-ol-κ3 N,N',O}bis-(nitrato-κO)copper(II) from synchrotron data

The title compound, [Cu(NO3)2(C10H16N2O)], has been synthesized and characterized by synchrotron single-crystal diffraction at 100 K. The CuII ion has a distorted square-pyramidal coordination geometry with two N and one O atoms of the C10H16N2O ligand and one nitrate anion in the equatorial plane and another nitrate anion at the axial position. The equatorial Cu-N and Cu-O bond lengths are in the range 1.9608 (14)-2.0861 (15) Å, which are shorter than the axial Cu-Onitrate bond length [2.1259 (16) Å]. In the crystal, mol-ecules are linked via inter-molecular N-H⋯O and O-H⋯O hydrogen bonds, forming a sheet structure parallel to the bc plane. The sheets are further linked through a face-to-face π-π inter-action [centroid-centroid distance = 3.994 (1) Å]. Weak inter-molecular C-H⋯O inter-actions are also observed in the sheet and between adjacent sheets.

ZnII doped and immobilized on functionalized magnetic hydrotalcite (Fe3O4/HT-SMTU-ZnII): a novel, green and magnetically recyclable bifunctional nanocatalyst for the one-pot multi-component synthesis of acridinediones under solvent-free conditions

Herein, the catalytic activity of a novel synthesized Fe₃O₄/HT-SMTU-Zn^II nanocatalyst, in the green and efficient synthesis of acridinediones, is described.