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One chiral heterotrimetallic compound, [Cu(H2O){(R,R)‐valcy}Tb(CH3OH)2(H2O)(μ‐CN)Fe(CN)5]·[Cu(H2O){(R,R)‐valcy}Tb(CH3OH)1.5(H2O)1.5(μ‐CN)Fe(CN)5]·7.85H2O·2CH3OH (1) (H2(R,R)‐valcy = N,N′‐bis(3‐methoxysalicylidene)‐1R,2R‐1,2‐diaminocyclohexane), has been prepared and structurally characterized by X‐ray single‐crystal diffraction. In 1, the asymmetric trinuclear {CuIITbIIIFeIII} units are assembled into 1‐D supramolecular single chain by hydrogen‐bonds and the supramolecular chains are further connected into 2D sheets. Magnetic studies show overall weak ferromagnetic interaction and magnetic anisotropy. The enantiomer of 1, denoted as complex 2, derived from N,N′‐bis(3‐methoxysalicylidene)‐1S,2S‐1,2‐diaminocyclohexane was also synthesized and characterized by PXRD, Infrared spectra, CD spectra, and fluorescence spectra. The results indicated that complexes 1 and 2 are isomorphous exhibiting similar fluorescence properties.

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Metastable‐state merocyanine photoacids (MCHs) have been widely applied to various chemical, material and biomedical areas to drive or control chemical processes with light. In this work, stoichiometry and association constants have been determined for inclusion complexes of a photoacid MCH1 with β‐cyclodextrin (β‐CD), 2‐hydroxypropyl‐β‐CD (HP‐β‐CD), γ‐CD and HP‐γ‐CD by means of UV‐Vis absorption titrations. The inclusion complexes were studied to enhance its acidity and chemical stability. Kinetic study showed that CDs stabilized the acidic metastable‐state and slowed its thermal relaxation. The acidity of the ground and metastable‐state (pKaGS and pKaMS) increased upon addition of CDs. The pKaMS of [MCH1·(γ‐CD)2] is as low as 0.92 in comparison with 2.25 for MCH1, which is close to the lowest pKaMS values (1.20 and 1.03) reported previously, in which case the MCH1 was structurally modified with alkylammonium side chains. Addition of CDs also significantly enhanced the chemical stability of MCH1 against hydrolysis, which is one of the major concerns for the application of MCHs. In particular, the addition of HP‐β‐CD increased the half‐life of MCH1 in aqueous solution by more than four times. Moreover, the quantum chemical calculations confirmed the stoichiometry and analyzed the binding sites and hydrogen bonds of the inclusion complexes.

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