Construction and structural transformation of two coordination sphere supramolecular isomers based on Co(ii) and 4-(2-pyridyl)-NH-1,2,3-triazole via one-pot synthesis

Two coordination sphere supramolecular isomers based on Co(ii) have been obtained via one-pot synthesis. The structural transformation process has been investigated with the help of mass spectroscopy and theoretical calculations.

Chiral tetranuclear copper(ii) complexes: synthesis, optical and magnetic properties

The chiral tetranuclear Cu(ii) cubane complexes with the general molecular formula [Cu₄(R-L₁)₄] (R-1) and [Cu₄(S-L₁)₄] (S-1) exhibit ferromagnetic exchange coupling, which is in contrast to the literature reports. This is corroborated by theoretical calculations.

In Situ Metal-Assisted Ligand Modification Induces Mn4 Cluster-to-Cluster Transformation: A Crystallography, Mass Spectrometry, and DFT Study

Dehydration of (S,S)-1,2-bis(1H-benzo[d]imidazol-2-yl)ethane-1,2-diol (H₄ L) to (Z)-1,2-bis(1H-benzo[d]imidazol-2-yl)ethenol) (H₃ L') was found to be metal-assisted, occurs under solvothermal conditions (H₂ O/CH₃ OH), and leads to [Mn^II ₄ (H₃ L)₄ Cl₂ ]Cl₂ ⋅5 H₂ O⋅5 CH₃ OH (Mn₄ L₄ ) and [Mn^II ₄ (H₂ L')₆ (μ₃ -OH)]Cl⋅4 CH₃ OH⋅H₂ O (Mn₄ L'₆ ), respectively. Their structures were determined by single-crystal XRD. Extensive ESI-MS studies on solutions and solids of the reaction led to the proposal consisting of an initial stepwise assembly of Mn₄ L₄ from the reactants via [MnL] and [Mn₂ L₂ ] below 80 °C, and then disassembly to [MnL] and [MnL₂ ] followed by ligand modification before reassembly to Mn₄ L'₆ via [MnL'], [MnL'₂ ], and [Mn₂ L'₃ ] with increasing solvothermal temperature up to 140 °C. Identification of intermediates [Mn₄ L_x L'_6-x ] (x=5, 4, 3, 2, 1) in the process further suggested an assembly/disassembly/in situ reaction/reassembly transformation mechanism. These results not only reveal that multiple phase transformations are possible even though they were not realized in the crystalline state, but also help to better understand the complex transformation process between coordination clusters during "black-box" reactions.