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The exploration of artificial metal-peptide assemblies (MPAs) is one of the most exciting fields because of their great potential for simulating the dynamics and functionality of natural proteins. However, unfavorable enthalpy changes make forming discrete complexes with large and adaptable cavities from flexible peptide ligands challenging. Here, we present a strategy integrating metal-cluster building blocks and peptides to create chiral metal-peptide assemblies and get a family of enantiopure [R-/S-Ni3L2]n (n = 2, 3, 6) MPAs, including the R-/S-Ni6L4 capsule, the S-Ni9L6 trigonal prism, and the R-/S-Ni18L12 octahedron cage. X-ray crystallography shows MPA formation reactions are highly solvent-condition-dependent, resulting in significant changes in ligand conformation and discrete cavity sizes. Moreover, we demonstrate that a structure transformation from Ni18L12 to Ni9L6 in the presence of benzopyrone molecules depends on the peptide conformational selection in crystallization. This work reveals that a metal-cluster building block approach enables facile bottom-up construction of artificial metal-peptide assemblies. The use of metal clusters to construct artificial protein-mimic structures with adaptable cavities has potential for simulating the dynamics and functionality of natural proteins. Here, the authors develop a family of chiral metal-peptide assemblies using {Ni3} clusters and flexible peptides, resulting in structures such as octahedral cages, trigonal prisms, and capsules. [ABSTRACT FROM AUTHOR]

Well-defined 3d–4f heterometallic supramolecular architectures have attracted attention because of their applications in the field of luminescence and magnetism. However, covalent metallo-supramolecular discrete complexes, decorated with hetero-metallic vertices, have never been reported because of the difficulties in design and control. Herein, we report a series of covalent metallo-supramolecular discrete complexes with 3d–4f vertices synthesized by hierarchical subcomponent self-assembly of tris(2-aminoethyl)amine, 2,6-diformyl-p-cresol, and lanthanide ions (Ln) with different amines and transition metal ions. The programmable self-assembly process results in the formation of triple-stranded hetero-metallic covalent organic discrete complexes, namely 3a–3c-(Ln, Zn) (Ln = SmIII, EuIII, DyIII, YbIII and LuIII) and 3a′-(Dy, Co), which are characterized by nuclear magnetic resonance (NMR) analysis, electrospray ionization time-of-flight mass spectrometry (ESI-TOF-MS), and single-crystal X-ray analysis. Photophysical investigations disclose that the organic skeleton of 3a-(Ln, Zn) exhibits an excellent sensitizing ability toward SmIII, EuIII, and YbIII ions, displaying characteristic luminescence emission in both the visible and near-infrared (NIR) regions. AC susceptibility measurements of 3a′-(Dy, Co) reveal the frequency-independent performance under zero dc field, suggesting the absence of slow relaxation of magnetization. This work offers a new approach for the fabrication of discrete metallic covalent architectures with 3d–4f vertices. [ABSTRACT FROM AUTHOR]

Brønsted-base active sites on a Pd4L2 cage facilitates enhanced catalytic efficiency, wide substrate scope and high turnover number (TON) for the one-pot photooxidation/Knoevenagel condensation reaction under mild conditions. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Understanding the kinetic process during the self‐assembly and chiral amplification of metal‐organic polyhedra (MOPs) is critical for the rational preparation of chiral MOPs. Herein, we report the ionic radius dependent kinetic processes for the self‐assembly and chiral amplification of Ln4L4‐type (Ln, Lanthanides; L, ligand) lanthanide tetrahedral cages. The chiral Eu4(LR)4 tetrahedral cage is structurally characterized by nuclear magnetic resonance (NMR), electrospray ionization time‐of‐flight mass spectrometry (ESI‐TOF‐MS), and single crystal X‐ray diffraction. Kinetic study on the stereo‐controlled self‐assembly of circularly polarized luminescence (CPL)‐active Ln4(LR)4 (Ln = LaIII, PrIII and EuIII) tetrahedra manifests that the larger ionic radius of Ln leads to faster assembly rates. Mixed‐ligand cage assembly experiments with chiral LR/S, achiral Lac and Ln (1 : 3 : 4 molar ratio) reveal that the self‐assembly and chiral amplification occur synchronously for the LaIII and PrIII cages, while two distinct steps, i.e., first self‐assembly and then chiral amplification, are observed for the EuIII cage. Such distinct kinetic behavior is attributed to different ligands exchange rates among the mixed‐ligand Ln4L4 cages. This work provides fundamental guidance for fabrication and property‐optimization of chiral lanthanide‐based molecular materials. [ABSTRACT FROM AUTHOR]

Organic pollutants cause severe environmental problems because of their damage to human health and ecological systems. Photocatalytic degradation of persistent organic pollutants is of great importance to address these hazards. Herein, we report a lanthanide organic polyhedra‐based hybrid material Gd8L12⊂MSN with the capability of photocatalytic dye degradation. Gd8L12⊂MSN was prepared by embedding the Gd8L12 complex into mesoporous silica nanoparticles (MSNs) using a "ship‐in‐a‐bottle" strategy. Photocurrent response tests revealed that this hybrid material is a potential semiconductor and could generate a rapid and steady photocurrent upon irradiation. Further dye degradation experiments indicated that it could photocatalyze the degradation of familiar organic dyes. Thereinto, compared with the critical Gd8L12 complex, the hybrid material exhibited an acceleration of 2.4 times and realized reusability. This not only offers a potential advanced photocatalyst for degrading persistent organic pollutants, but also provides a strategy for the application of supramolecular materials in environmental science. [ABSTRACT FROM AUTHOR]