Synthesis and magnetic properties of a dinuclear manganese(II) complex with two manganese(II) ions of C2-twisted octahedral geometry

Transition Metal Complexes of Thiosemicarbazides, Thiocarbohydrazides, and Their Corresponding Carbazones with Cu(I), Cu(II), Co(II), Ni(II), Pd(II), and Ag(I)-A Review

This review focuses on some interesting and recent applications of transition metals towards the complexation of thiosemicarbazides, thiocarbohydrazides, and their corresponding carbazones. We started the review with a description of the chosen five metals, including Cu[Cu(I), Cu(II], Co(II), Ni(II), Pd(II), and Ag(I) and their electronic configurations. The stability of the assigned complexes was also discussed. We shed light on different routes describing the synthesis of these ligands. We also reported on different examples of the synthesis of Cu(I), Cu(II), Co(II), Ni(II), Ag(I), and Pd(II) of thiosemicarbazide and thiocarbohydrazide complexes (until 2022). This review also deals with a summary of the fruitful use of metal complexes of thiosemicarbazones and thiocarbazones ligands in the field of catalysis. Finally, this recent review focuses on the applications of these complexes related to their biological importance.

Structures of Dimer-of-Dimers Type Defect Cubane Tetranuclear Copper(II) Complexes with Novel Dinucleating Ligands

Only a limited number of multinucleating ligands can stably maintain multinuclear metal structures in aqueous solutions. In this study, a water-soluble dinucleating ligand, 2,6-bis{[N-(carboxylatomethyl)-N-methyl-amino]methyl}-4-methylphenolate ((sym-cmp)³⁻), was prepared and its copper(II) complexes were structurally characterized. Using the single-crystal X-ray diffraction method, their dimer-of-dimers type defect cubane tetranuclear copper(II) structures were characterized for [Cu₄(sym-cmp)₂Cl₂(H₂O)₂] and [Cu₄(sym-cmp)₂(CH₃O)₂(CH₃OH)₂]. In the complexes, each copper(II) ion has a five-coordinate square-pyramidal coordination geometry. The coordination bond character was confirmed by the density functional theory (DFT) calculation on the basis of the crystal structure, whereby we found the bonding and anti-bonding molecular orbitals. From the cryomagnetic measurement and the magnetic analysis, overall antiferromagnetic interaction was observed, and this magnetic behavior is also explained by the DFT result. Judging from the molar conductance and the electronic spectra, the bridging chlorido ligand dissociates in water, but the dinuclear copper(II) structure was found to be maintained in an aqueous solution. In conclusion, the tetranuclear copper(II) structures were crystallographically characterized, and the dinuclear copper(II) structures were found to be stabilized even in an aqueous solution.

Coordination-Induced Interlinked Covalent- and Metal-Organic-Framework Hybrids for Enhanced Lithium Storage

Covalent organic frameworks (COF) or metal-organic frameworks have attracted significant attention for various applications due to their intriguing tunable micro/mesopores and composition/functionality control. Herein, a coordination-induced interlinked hybrid of imine-based covalent organic frameworks and Mn-based metal-organic frameworks (COF/Mn-MOF) based on the MnN bond is reported. The effective molecular-level coordination-induced compositing of COF and MOF endows the hybrid with unique flower-like microsphere morphology and superior lithium-storage performances that originate from activated Mn centers and the aromatic benzene ring. In addition, hollow or core-shell MnS trapped in N and S codoped carbon (MnS@NS-C-g and MnS@NS-C-l) are also derived from the COF/Mn-MOF hybrid and they exhibit good lithium-storage properties. The design strategy of COF-MOF hybrid can shed light on the promising hybridization on porous organic framework composites with molecular-level structural adjustment, nano/microsized morphology design, and property optimization.