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A series of [2]catenanes has been prepared from di‐NHC building blocks by utilizing solvophobic effects and/or π⋅⋅⋅π stacking interactions. The dinickel naphthobiscarbene complex syn‐[1] and the kinked biphenyl‐bridged bipyridyl ligand L2 yield the [2]catenane [2‐IL](OTf)4 by self‐assembly. Solvophobic effects are pivotal for the formation of the interlocked species. Substitution of the biphenyl‐linker in L2 for a pyromellitic diimide group gave ligand L3, which yielded in combination with syn‐[1] the [2]catenane [3‐IL](OTf)4. This assembly exhibits enhanced stability in diluted solution, aided by additional π⋅⋅⋅π stacking interactions. The π⋅⋅⋅π stacking was augmented by the introduction of a pyrene bridge between two NHC donors in ligand L4. Di‐NHC precursor H2‐L4(PF6)2 reacts with Ag2O to give the [Ag2L42]2 [2]catenane [4‐IL](PF6)4, which shows strong π⋅⋅⋅π stacking interactions between the pyrene groups. This assembly was readily converted into the [Au2L42]2 gold species [5‐IL](PF6)4, which exhibits exceptional stability based on the strong π⋅⋅⋅π stacking interactions and the enhanced stability of the Au‐CNHC bonds. [ABSTRACT FROM AUTHOR]

Tangled cubes feature the topology of typical Platonic cubes, with their "faces" traversed by edges in different ways. This study generates an "A‐type" tangled metallocube from the reaction of binuclear gold‐NHC complex and H2S. The tangled cube topology was validated by multinuclear nuclear magnetic resonance (NMR) spectroscopy, high‐resolution electrospray‐ionization (HR‐ESI) mass spectrometry, and single‐crystal X‐ray diffraction analysis. This study offers a simple and effective approach to designing and fabricating new, topologically unique molecular structures. [ABSTRACT FROM AUTHOR]

Controlling the size and surface functionalization of nanoparticles (NPs) can lead to improved properties and applicability. Herein, we demonstrate the efficiency of the metal‐carbene template approach (MCTA) to synthesize highly robust and soluble three‐dimensional polyimidazolium cages (PICs) of different sizes, each bearing numerous imidazolium groups, and use these as templates to synthesize and stabilize catalytically active, cavity‐hosted, dispersed poly‐N‐heterocyclic carbene (NHC)‐anchored gold NPs. Owing to the stabilization of the NHC ligands and the effective confinement of the cage cavities, the as‐prepared poly‐NHC‐shell‐encapsulated AuNPs displayed promising stability towards heat, pH, and chemical regents. Most notably, all the Au@PCCs (PCC=polycarbene cage) exhibited excellent catalytic activities in various chemical reactions, together with high stability and durability. [ABSTRACT FROM AUTHOR]

A series of supramolecular assemblies of types [Ag8(L)4](PF6)8 and [Ag4(L)2](PF6)4, obtained from the tetraphenylethylene (TPE) bridged tetrakis(1,2,4‐triazolium) salts H4‐L(PF6)4 and AgI ions, is described. The assembly type obtained dependends on the N‐wingtip substituents of H4‐L(PF6)4. Changes in the lengths of the N4‐wingtip substituents enables controlled formation of assemblies with either [Ag4(L)2](PF6)4 or [Ag8(L)4](PF6)8 stoichiometry. The molecular structures of selected [Ag8(L)4](PF6)8 and [Ag4(L)2](PF6)4 assemblies were determined by X‐ray diffraction analyses. While H4‐L(PF6)4 does not exhibit fluorescence in solution, their tetra‐NHC (NHC=N‐heterocyclic carbene) assemblies do upon NHC–metal coordination. Upon irradiation, all assemblies undergo a light‐induced, supramolecule‐to‐supramolecule structural transformation by an oxidative photocyclization involving phenyl groups of the TPE core, resulting in a significant change of the luminescence properties. [ABSTRACT FROM AUTHOR]

Metallosupramolecular poly‐NHC‐metal assemblies were prepared from trigonal hexakis (H6‐1 a(PF6)6 and H6‐1 b(PF6)6) or nonakis (H9‐3(BF4)9) imidazolium salts and Ag2O. Complexes [Ag6(1 a)2](PF6)6 and [Ag6(1 b)2](PF6)6 are built from six Ag+ ions sandwiched between two trigonal hexacarbene ligands with an inner and an outer NHC donor in each of the three ligand arms. The metal atoms are arranged in two triangles. The hexakis‐NHC ligands bear cinnamic ester groups at the outlying NHC donors, used in postsynthetic [2+2] cycloaddition reactions linking two hexakis‐NHC ligands by three cyclobutane units to give complexes [Ag6(2 a)](PF6)6 and [Ag6(2 b)](PF6)6 bearing a dodecacarbene ligand. From the related nonakisimidazolium salt H9‐3(BF4)9, complex [Ag9(4)](BF4)9 bearing an octadecacarbene ligand was obtained. Removal of the template metals yielded very large, stable, polyimidazolium cations with 12 or 18 internal imidazolium groups. [ABSTRACT FROM AUTHOR]