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Abstract Practical applications of lithium metal batteries are often limited by low cycling efficiencies and uncontrolled lithium dendrite growth caused by unstable and heterogeneous lithium‐electrolyte interfaces. To address this issue, a calix[4]pyrrole‐based wavy covalent organic framework (WCOF) is developed that acts as a protective layer to suppress Li dendrite growth and reduce side reactions on the Li anode. The presentWCOFis porous and contains calix[4]pyrrole units acting as “molecular traps” that allow efficient PF₆⁻anion capture while allowing for uniform Li⁺diffusion. This provides structurally stable artificial protective layers that permit high Li⁺transference numbers. The resulting solid electrolyte interphases permit ultralong‐term stable cycling at a current density of 1 mA cm⁻²and reversible lithium plating/stripping (over 2500 h) at an areal capacity of 2 mAh cm⁻². The protected anodes of this study also demonstrated excellent cell stability through 260 cycles when paired with high‐voltage cathodes (NCM811 with high mass loading: 20 mg cm⁻²). 

Abstract Carbaporphyrin dimers, investigated for their distinctive electronic structures and exceptional properties, have predominantly consisted of systems containing identical subunits. This study addresses the associated knowledge gap by focusing on asymmetric carbaporphyrin dimers with Janus-like characteristics. The synthesis of a Janus-type carbaporphyrin pseudo-dimer5is presented. It displays antiaromatic characteristics on the fused side and nonaromatic behavior on the unfused side. A newly synthesized tetraphenylene (TPE) linked bis-dibenzihomoporphyrin8and a previously reported dibenzo[g,p]chrysene (DBC) linked bis-dicarbacorrole9were prepared as controls. Comprehensive analyses, including¹H NMR spectral studies, single crystal X-ray diffraction analyses, and DFT calculations, validate the mixed character of5. A further feature of the Janus pseudo-dimer5is that it may be transformed into a heterometallic complex, with one side coordinating a Cu(III) center and the other stabilizing a BODIPY complex. This disparate regiochemical reactivity underscores the potential of carbaporphyrin dimers as versatile frameworks, with electronic features and site-specific coordination chemistry controlled through asymmetry. These findings position carbaporphyrin dimers as promising candidates for advances in electronic structure studies, coordination chemistry, materials science, and beyond. 

Abstract New stimulus‐responsive scaffolds are of interest as constituents of hierarchical supramolecular ensembles. 1,3,5–2,4,6‐Functionalized, facially segregated benzene moieties have a time‐honored role as building blocks for host molecules. However, their user as switchable motifs in the construction of multi‐component supramolecular structures remains poorly explored. Here, we report a molecular cage 1, which consists of a bent anthracene dimer3paired with 1,3,5‐tris(aminomethyl)‐2,4,6‐triethylbenzene2. As the result of the pH‐inducedababab↔bababaisomerization of the constituent‐functionalized benzene units derived from2, this cage can reversibly convert between an open state and a closed form, both in solution and in the solid state. Cage 1was used to create stimuli‐responsive hierarchical superstructures, namely Russian doll‐like complexes with [K⊂18‐crown‐6⊂1]⁺and [K⊂cryptand‐222⊂1]⁺. The reversible assembly and disassembly of these superstructures could be induced by switching cage 1from its open to closed form. The present study thus provides an unusual example where pH‐triggered conformation motion within a cage‐like scaffold is used to control the formation and disassociation of hierarchical ensembles. 

A covalently bridged macrocycle exhibits multifunctional properties, including dual-state emission, intramolecular energy transfer, Cu²⁺sensing, and mechanochromism, while permitting latent finger print imaging.