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Two heteropolynuclear complexes, namely [Cu2(L)Ce(NO3)3] and [{Cu2(L)Y(NO3)2(μ-AcO)}{Cu2(L)Y(NO3)2(μ-NO3)(CH3OH)}]·4CH3OH, were synthesized through the reaction of a newly synthesized bis(salamo)-based ligand (H4L), Cu(OAc)2·H2O and Ln(NO3)3·6H2O (Ln = Ce and Y), respectively. Single crystal structure analyses showed that the [CuII2CeIII] and [CuII4YIII2] complexes contained similar trinuclear [CuII2LnIII] structures. The difference was that the [CuII4YIII2] complex consisted of two crystallographically independent and chemically different trinuclear complexes with coordination and free solvent molecules. Among the two heteropolynuclear metal complexes, only the [CuII2CeIII] complex showed catecholase activity and benzoxazinone synthase activity under normal temperature and aerobic conditions. For catecholase activity, the calculated Kcat of the [CuII2CeIII] complex was 346.5 h−1, and the Kcat of p-benzoxazinone synthase activity was 9.73 h−1. Compared with the [CuII4YIII2] complex, we speculated that the main reason for the high catalytic function of the [CuII2CeIII] complex is the presence of three nitrate groups coordinated with the central CeIII atom. Evidence from mass spectrometry and cyclic voltammetry curves indicated that there may be heterometallic cooperation, in which CeIII binds to the substrate, while the metallic copper transformed between CuII and CuI through redox reactions. In addition, the catalytic mechanism was inferred through electrospray mass spectrometry and cyclic voltammetry, and fluorescence properties were studied and Hirshfeld surface analyses were also conducted. [ABSTRACT FROM AUTHOR]

One homo-trinuclear 3d and five novel windmill-type hetero-pentanuclear 3d-4f complexes [Zn3(L)(OAc)2(H2O)]·CH2Cl2 (1), [Zn4(L)2Sm(NO3)2(EtOH)2]NO3·H2O·2CHCl3 (2), [Zn4(L)2Eu(NO3)2(EtOH)2]NO3·C2H5OH·2CHCl3 (3), [Zn4(L)2Gd(NO3)2(EtOH)2]NO3·C2H5OH·2CHCl3 (4), [Zn4(L)2Tb(NO3)2(EtOH)2]NO3·C2H5OH (5) and [Zn4(L)2Dy(NO3)2(EtOH)2]NO3·C2H5OH·2CHCl3 (6) were synthesized by the reactions of a new bis(Salamo)-based tetraoxime ligand (H4L) with Zn(OAc)2·2H2O and Ln(NO3)3·6H2O (Ln = Sm, Eu, Gd, Tb and Dy), respectively. The structures of complexes 1–6 were characterized via elemental analyses, FT-IR spectroscopy, UV-Vis spectroscopy and single crystal X-ray crystallography, and their fluorescence properties, catalytic activities and Hirshfeld surface analyses were studied. [ABSTRACT FROM AUTHOR]