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1. Selective, cofactor-mediated catalytic oxidation of alkanethiols in a self-assembled cage host

   https://doi.org/10.1039/d0cc05765g  

   da Camara, Bryce; Dietz, Philip C.; Chalek, Kevin R.; Mueller, Leonard J.; Hooley, Richard J. (November 2020, Chemical Communications)

   null (Ed.)

   A spacious Fe( ii )-iminopyridine self-assembled cage complex can catalyze the oxidative dimerization of alkanethiols, with air as stoichiometric oxidant. The reaction is aided by selective molecular recognition of the reactants, and the active catalyst is derived from the Fe( ii ) centers that provide the structural vertices of the host. The host is even capable of size-selective oxidation and can discriminate between alkanethiols of identical reactivity, based solely on size. 

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2. No, Not That Way, the Other Way: Creating Active Sites in Self-Assembled Host Molecules

   https://doi.org/10.1055/s-0040-1707125  

   Hooley, Richard J. (January 2020, Synlett)

   This Account describes our efforts over the last decade to synthesize self-assembled metal–ligand cage complexes that display reactive functional groups on their interiors. This journey has taken us down a variety of research avenues, including studying the mechanism of reversible self-assembly, analyzing ligand self-sorting properties, post-assembly reactivity, molecular recognition, and binding studies, and finally reactivity and catalysis. Each of these individual topics are discussed here, as are the lessons learned along the way and the future research outlook. These self-assembled hosts are the closest mimics of enzymes to date, as they are capable of size- and shape-selective molecular recognition, substrate activation and turnover, as well as showing less common ‘biomimetic’ properties such as the ability to employ cofactors in reactivity, and alter the prevailing mechanism of the catalyzed reactions. 1 Introduction 2 Paddlewheels and Self-Sorting Behavior 3 First-Row Transition-Metal-Mediated Assembly: Sorting and Stereochemical Control 4 Post-Assembly Reactivity 5 Molecular Recognition and Catalysis 6 Conclusions and Outlook 

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3. 1,3,5–2,4,6‐Functionalized Benzene Molecular Cage: An Environmentally Responsive Scaffold that Supports Hierarchical Superstructures

   https://doi.org/10.1002/anie.202407805  

   Pang, Xin‐Yu; Zhou, Hang; Xie, Xiaojiang; Jiang, Wei; Yang, Yinhua; Sessler, Jonathan_L; Gong, Han‐Yuan (July 2024, Angewandte Chemie International Edition)

   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. 

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4. Glycosyl Sulfonates Beyond Triflates

   https://doi.org/10.1002/tcr.202100141  

   Bennett, Clay S. (June 2021, The Chemical Record)

   Abstract While glycosyl triflates are frequently invoked as intermediates in many chemical glycosylation reactions, the chemistry of other glycosyl sulfonates remains comparatively underexplored. Given the reactivity of sulfonates can span several orders of magnitude, this represents an untapped resource for the development of stereoselective glycosylation reactions. This personal account describes our laboratories efforts to take advantage of this reactivity to develop β‐specific glycosylation reactions. Initial investigations led to the development of 2‐deoxy‐sugar tosylates as highly selective donors for β‐glycoside synthesis, an approach which has been used to great success by our group and others for the construction of deoxy‐sugar oligosaccharides and natural products. Subsequent studies demonstrate that “matching” the reactivity of the sulfonate to that of the sugar donor leads to highly selective S_N2‐glycosylations with a range of substrates. 

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5. The origin of charged domains on the surface of ferroelastic BiVO ₄ co‐doped with sodium and molybdenum

   https://doi.org/10.1111/jace.20482  

   Pisat, Ajay_S; Adler, Jackson_C; Salvador, Paul_A; Rohrer, Gregory_S (March 2025, Journal of the American Ceramic Society)

   Abstract Ferroelastic BiVO₄has charged surface domains, even though its crystal structure is non‐polar. These charged domains can be detected by piezo‐force microscopy and lead to spatially selective photochemical reactions. The photochemical reactivity of (Bi_0.96Na_0.04)(V_0.92Mo_0.08)O₄is studied above and below the ferroelastic transition temperature to better understand the origin of charged ferroelastic domains. The results demonstrate that spatially selective reactivity occurs above the ferroelastic transition temperature, similar to what is observed below the transition temperature. Furthermore, when the sample is cooled after brief excursions above the transition temperature, the domains reform with a microstructure that is indistinguishable from what is observed before the transition. The results are consistent with the idea that inhomogeneous distributions of charged point defects, created by stress in the ferroelastic domains, lead to charged domains that promote spatially selective photochemical reactions. If these inhomogeneous defect distributions are not homogenized above the transition temperature, they can template the re‐creation of the original domain microstructure after the transformation back to the ferroelastic phase. 

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