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Novel tridentate N2O‐type ligands L1–L4 (((((X‐benzyl)pyridine‐2‐yl)methylamino)methyl)phenol); L1 for X=4‐CH3, L2 for X=H, L3 for X=2‐F, L4 for X=4‐CF3) and their dinuclear copper(II) complexes C1–C4 (C1 for [(L1)2Cu2(NO3)2], C2 for [(L2)2Cu2(NO3)2], C3 for [(L3)2Cu2(NO3)2] and C4 for [(L4)2Cu2(NO3)2]) was synthesized and verified by 1H NMR, IR, and ESI‐Mass. The structural forms of the copper complexes were determined by X‐ray crystallography. The dinuclear copper complexes C1–C4 showed efficient ring‐opening properties of epoxides with methanol under mild conditions. In particular, the copper complex C1 having electron‐donating group in the ligand showed the most efficient reactivity in the ring opening of epoxides. The sole attack at the benzylic carbon of styrene oxide and the less steric preference in 1,2‐epoxyhexane demonstrated that the regiochemistry of the ring opening catalyzed by dinuclear copper complexes might be dependent on the electronic feature of epoxide. [ABSTRACT FROM AUTHOR]

A novel multiple target sensor, (E)-5-((4-(diethylamino)-2-hydroxybenzyldene)amino)-1H-imidazole-4-carboxamide (DHIC), was synthesized for fluorescence detection of Zn2+ and S2− and colorimetric detection of Fe3+/2+ in aqueous media. DHIC can operate as a turn “on–off” sequential fluorescent sensor for Zn2+ and S2−. Detection limits (1.59 μM and 8.03 μM) for Zn2+ and S2− are below the WHO standards (76.0 μM and 14.7 μM). The DHIC–Zn2+ complex could be reversibly reused with ethylenediaminetetraacetic acid. Importantly, DHIC could image sequentially Zn2+ and S2− in living cells. Moreover, DHIC displayed a discriminatory color change from pale yellow to orange yellow to Fe3+/2+. The detection limit of DHIC for Fe3+/2+ (0.73 μM and 1.11 μM) is far below the EPA drinking water standard (5.37 μM). The sensor DHIC could be applied to analyze Fe3+ in real samples. [ABSTRACT FROM AUTHOR]