Anion exchange coupled with the reduction and dimerisation of a copper(ii) nitrate complex of tripyridyl dithioether via a single-crystal-to-single-crystal transformation

Solvent-Effected Coordination Variation of Flexible Ligands to Cu(II) for the Formation of 1D and 2D Secondary Building Units for Metal-Organic Frameworks

Producing more than one structure from the same set of metal and ligand precursors will grant structural diversity in metal-organic framework (MOF) systems. One of the biggest obstacles of getting structural diversity for the late transition metals is that the coordination mode is pretty much fixed by nature. Herein, we show that two different coordination modes to Cu(II) are possible for flexible ligands containing hydrophilic terminal groups through solvent guidance. It is demonstrated that trans,trans-muconic acid (H₂muco) ligands coordinate to Cu(II) to form Cu(II) muconate MOFs having a 1D chain structure and a 2D plane structure in water-rich and DMF-rich water-DMF mixed solvent systems, respectively. It is suggested that the interaction between ligands and solvent is responsible for the selective coordination. A similar result was observed from the attempts using the fumaric acid ligand. Our results provide a new direction to obtain diverse secondary building units for the construction of diverse MOFs.

Thermally induced transformation of a Cu4I4-based cluster to a Cu2I2-based cluster under mild conditions

A reaction of 6,6'-bis((benzylthio)methyl)-2,2'-bipyridine (L) with CuI at room temperature led to one Cu4I4-based cluster, which could be thermally transformed to a Cu2I2-based one under mild conditions due to the formation of a Cu-S bond. Along with the structural transformation, remarkable changes in the color and luminescence have been triggered.

Copper(i)–iodide cluster structures as functional and processable platform materials

This review provides a complete overview of the progress towards implementation of CuI-nanoclusters in functional materials and devices.

Cu(i) Iodide coordination polymers with aromatic thioamides

The reaction of 4-pyridinethiobenzamide (PyTBA) with CuI and KI aqueous solution in acetone or THF under slow diffusion gives rise to the formation of single crystals of two coordination polymers [CuIPyTBA]_n·nS (S = acetone; 1/3THF).

Four 3D coordination polymers based on layers with single syn-anti carboxylate bridges: synthesis, structures, and magnetic properties

Four novel coordination polymers (CPs) based on a new 4-(3,5-dicarboxylphenyl) picolinic acid ligands (H₃L), [M₃(L)₂(H₂O)₆]·4H₂O (M₃ = Mn₃, 1; Co₃, 2; Ni₃, 3, Co_1.01Ni_1.99, 4), have been hydrothermally synthesized, and structurally and magnetically characterized. In these isomorphous CPs, octahedrally coordinated metal ions are linked by the single syn–anti carboxylate bridge (μ-COO) to give linear trinuclear motifs. The motifs are connected through the other single syn–anti carboxylate bridge (μ-COO) to give a 2D (4,4) layer, and the layers are interlinked by the L ligands into 3D frameworks. Magnetic measurement indicates that antiferromagnetic interactions between metal ions are mediated through the single syn–anti carboxylate bridges in 1 and 2, while the same carboxylate bridges in 3 transmit ferromagnetic couplings. The bimetallic CP 4 shows interesting complicated magnetic behaviors due to the competition effect of Co(ii) and Ni(ii) ions.

Four 3D carboxylate-bridged metal(II) compounds were prepared. Mn(II) and Co(II) compounds show AFM interactions, while FM coupling is found in Ni(II) compound. The bimetallic shows interesting competition effect of FM and AFM interactions.

Transition-Metal-Triggered High-Efficiency Lithium Ion Storage via Coordination Interactions with Redox-Active Croconate in One-Dimensional Metal-Organic Anode Materials

Coordination polymers (CPs) have powerful competence as anode materials for lithium-ion batteries (LIBs) owing to their structural diversity, tunable functionality, and facile and mild synthetic conditions. Here, we show that two isostructural one-dimensional croconate-based CPs, namely, [M(C₅O₅)(H₂O)₃]_n (M = Mn for 1 and Co for 2; C₅O₅^2- = croconate dianion), can work as high-performance electrode materials for rechargeable LIBs. By means of the coordination between the redox-active transition metal ion and the ligand, the anode materials were stable in the electrolyte and showed high capacities, impressive rate capabilities, and excellent cycling performance during the discharging/charging processes. The chain-based supramolecular structures of the CPs also make them stand out from a crowd of porous three-dimensional molecular materials due to their free channels between the chains for lithium ion diffusion. When tested in a voltage window of 0.01-2.4 V at 100 mA g^-1, CPs 1 and 2 demonstrated high discharge specific capacities of 729 and 741 mA h g^-1, respectively. The synergistical redox reactions on both metal centers and the organic moieties play a crucial role in the high electrochemical performance of CPs 1 and 2. After undergoing elevated discharging/charging rates to 2 A g^-1, the electrodes could finally recover their capabilities as those in the initial stage when the current rate was back to 100 mA g^-1, indicating excellent rate performance and outstanding cycling stabilities of the materials.

Snapshot and crystallographic observations of kinetic and thermodynamic products for NO2S2 macrocyclic complexes

Direct observation and structural characterization of a kinetic product and a thermodynamic product for complexes with an NO₂S₂ macrocycle (L) are reported. L reacts with copper(I) iodide to give a mononuclear complex [Cu(L)]₂(Cu₂I₄)·2CH₂Cl₂ (1), featuring three separate units. When cadmium(II) iodide was reacted with L, an anion-coordinated complex [Cd(L)I]₂(Cd₂I₆)·4CH₃CN (2) with a needle-type crystal shape was formed as the kinetic product. Interestingly, when the needle-type kinetic product was left undisturbed in the mother solution it gradually transformed to the pseudo-dimer complex [Cd₂(L)₂I₂](Cd₂I₆) (3) with a brick-type crystal shape as the thermodynamic product. The dissolution-recrystallization process resulted in the elimination of the lattice solvent molecules (aceto-nitrile) in 2 and the contraction of two neighboring macrocyclic complex units [Cd(L)I]⁺, forming the pseudo-dimer 3via an intermolecular Cd⋯I interaction between two monomers. For the entire process from kinetic to thermodynamic products, it was possible to obtain sequential photographic snapshots, single-crystal X-ray structures and powder X-ray diffraction patterns. For the copper(I) and cadmium(II) complexes, competitive NMR results agree with the solid-state data that show copper(I) has a higher affinity for L than does cadmium(II).

Coordination preference of hexa(2-pyridyl)benzene with copper(ii) directed by hydrogen bonding

Coordination modes of hexa(2-pyridyl)benzene ligand with copper(ii) ions were controlled by different solvents mainly due to hydrogen bonding.

Solvent-mediated single-crystal-to-single-crystal transformation from a dimeric to tetrameric copper(i) complex based on a substituted pyridine derived from a Diels–Alder adduct

A solution of [Cu₂I₂L₂(MeCN)₂] (1) in dichloromethane (DCM) assisted the removal of MeCN and N-(4-pyridinyl)-9,10-dihydroethanoanthracene-11,12-dicarboximide (L) from the crystal of 1, leading to an unprecedented SCSC transformation.