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1. Ionothermal Synthesis of Metal‐Organic Frameworks Using Low‐Melting Metal Salt Precursors**

   https://doi.org/10.1002/anie.202218252  

   Azbell, Tyler J.; Pitt, Tristan A.; Bollmeyer, Melissa M.; Cong, Christina; Lancaster, Kyle M.; Milner, Phillip J. (March 2023, Angewandte Chemie International Edition)

   Abstract Metal‐organic frameworks (MOFs) are porous, crystalline materials constructed from organic linkers and inorganic nodes with myriad potential applications in chemical separations, catalysis, and drug delivery. A major barrier to the application of MOFs is their poor scalability, as most frameworks are prepared under highly dilute solvothermal conditions using toxic organic solvents. Herein, we demonstrate that combining a range of linkers with low‐melting metal halide (hydrate) salts leads directly to high‐quality MOFs without added solvent. Frameworks prepared under these ionothermal conditions possess porosities comparable to those prepared under traditional solvothermal conditions. In addition, we report the ionothermal syntheses of two frameworks that cannot be prepared directly under solvothermal conditions. Overall, the user‐friendly method reported herein should be broadly applicable to the discovery and synthesis of stable metal‐organic materials. 

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2. Recent Advances in Metal‐Catalyzed Functionalization of Indoles

   https://doi.org/10.1002/adsc.202100116  

   Urbina, Kelvin; Tresp, David; Sipps, Karli; Szostak, Michal (April 2021, Advanced Synthesis & Catalysis)

   Abstract Indole is one of the most important heterocycles in organic synthesis, natural products, and drug discovery. Recently, tremendous advances in the selective functionalization of indoles have been reported. Although the most important advances have been powered by transition metal catalysis, exceedingly useful methods in the absence of transition metals have also been reported. In this review, we provide an overview of functionalization reactions of indoles that have been published in the last years with a focus on the most recent advances, aims, and future trends. The review is organized by the positional selectivity and type of methods used for functionalization. In particular, we discuss major advances in transition‐metal‐catalyzed C−H functionalization at the classical C2/C3 positions, transition‐metal‐catalyzed C−H functionalization at the remote C4/C7 positions, transition‐metal‐catalyzed cross‐coupling, and transition‐metal‐free functionalization. magnified image 

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3. Metal–Organic Frameworks with Low‐Valent Metal Nodes

   https://doi.org/10.1002/anie.202206353  

   Sikma, R. Eric; Balto, Krista P.; Figueroa, Joshua S.; Cohen, Seth M. (July 2022, Angewandte Chemie International Edition)

   Abstract Metal–organic frameworks (MOFs) are crystalline, 2‐ and 3‐dimensional coordination polymers formed by bonding interactions between metals and multitopic organic ligands. These are typically formed using hard Lewis basic organic ligands with high oxidation state metal ions. The use of low‐valent metals as structural elements in MOFs is far less common, despite the widespread use of such metals for catalysis, luminescence, and other applications. This Minireview focuses on recent advances in the field of low‐valent MOFs and offers a perspective on the future development of these materials. 

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4. Microwave Absorption of Organic Metal Halide Nanotubes

   https://doi.org/10.1002/admi.201901270  

   Lin, Haoran; Green, Michael; Xu, Liang‐Jin; Chen, Xiaobo; Ma, Biwu (December 2019, Advanced Materials Interfaces)

   Abstract Organic metal halide hybrids have attracted tremendous research interests owing to their outstanding optical and electronic properties suitable for various applications, including photovoltaics, light‐emitting diodes, and photodetectors. Recently, the multifunctionality of this class of materials has been further explored beyond their optical and electronic properties. Here, for the first time the microwave electromagnetic properties of a 1D organic metal halide hybrid, (C₆H₁₃N₄)₃Pb₂Br₇, a single crystalline bulk assembly of organic metal halide nanotubes, are reported. Good microwave absorption performance with a large reflection loss value of −18.5 dB and a threshold bandwidth of 1.0 GHz is discovered for this material, suggesting its potential as a new microwave absorber. This work reveals a new functionality of organic metal halide hybrids and provides a new material class for microwave absorption application studies. 

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5. Dynamic structural evolution of MgO-supported palladium catalysts: from metal to metal oxide nanoparticles to surface then subsurface atomically dispersed cations

   https://doi.org/10.1039/D4SC00035H  

   Chen, Yizhen; Rana, Rachita; Zhang, Yizhi; Hoffman, Adam S; Huang, Zhennan; Yang, Bo; Vila, Fernando D; Perez-Aguilar, Jorge E; Hong, Jiyun; Li, Xu; et al (May 2024, Chemical Science)

   Supported noble metal catalysts, ubiquitous in chemical technology, often undergo dynamic transformations between reduced and oxidized states—which influence the metal nuclearities, oxidation states, and catalytic properties. 

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