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1. Suzuki–Miyaura cross-coupling of esters by selective O–C(O) cleavage mediated by air- and moisture-stable [Pd(NHC)(μ-Cl)Cl] ₂ precatalysts: catalyst evaluation and mechanism

   https://doi.org/10.1039/D1CY00312G  

   Yang, Shiyi; Zhou, Tongliang; Poater, Albert; Cavallo, Luigi; Nolan, Steven P.; Szostak, Michal (January 2021, Catalysis Science & Technology)

   null (Ed.)

   The cross-coupling of aryl esters has emerged as a powerful platform for the functionalization of otherwise inert acyl C–O bonds in chemical synthesis and catalysis. Herein, we report a combined experimental and computational study on the acyl Suzuki–Miyaura cross-coupling of aryl esters mediated by well-defined, air- and moisture-stable Pd( ii )–NHC precatalysts [Pd(NHC)(μ-Cl)Cl] 2 . We present a comprehensive evaluation of [Pd(NHC)(μ-Cl)Cl] 2 precatalysts and compare them with the present state-of-the-art [(Pd(NHC)allyl] precatalysts bearing allyl-type throw-away ligands. Most importantly, the study reveals [Pd(NHC)(μ-Cl)Cl] 2 as the most reactive precatalysts discovered to date in this reactivity manifold. The unique synthetic utility of this unconventional O–C(O) cross-coupling is highlighted in the late-stage functionalization of pharmaceuticals and sequential chemoselective cross-coupling, providing access to valuable ketone products by a catalytic mechanism involving Pd insertion into the aryl ester bond. Furthermore, we present a comprehensive study of the catalytic cycle by DFT methods. Considering the clear advantages of [Pd(NHC)(μ-Cl)Cl] 2 precatalysts on several levels, including facile one-pot synthesis, superior atom-economic profile to all other Pd( ii )–NHC catalysts, and versatile reactivity, these should be considered as the ‘first-choice’ catalysts for all routine applications in ester O–C(O) bond activation. 

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2. Li _3.6 In ₇ S _11.8 Cl: an air- and moisture-stable superionic conductor

   https://doi.org/10.1039/d5sc01907a  

   Oyekunle, Ifeoluwa P; Truong, Erica; Poudel, Tej P; Chen, Yudan; Jin, Yongkang; Ojelade, Islamiyat A; Deck, Michael J; Ogbolu, Bright; Islam, Md Mahinur; Ojha, Pawan K; et al (January 2025, Chemical Science)

   Li_3.6In₇S_11.8Cl has a face-centered cubic arrangement of S²⁻/Cl⁻stabilized by Li⁺/In³⁺that form 3D ion conduction paths. The moisture stability and fast ion conduction make Li_3.6In₇S_11.8Cl a promising electrolyte for solid-state batteries. 

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3. Solvothermal Synthesis of [Cr ₇ S ₈ (en) ₈ Cl ₂ ]Cl ₃  ⋅ 2H ₂ O with Magnetically Frustrated [Cr ₇ S ₈ ] ⁵⁺ Double‐Cubes**

   https://doi.org/10.1002/chem.202103761  

   Gamage, Eranga_H; Clark, Judith_K; Yazback, Maher; Cheng, Hai‐Ping; Shatruk, Michael; Kovnir, Kirill (December 2021, Chemistry – A European Journal)

   Abstract A novel transition metal chalcohalide [Cr₇S₈(en)₈Cl₂]Cl₃ ⋅ 2H₂O, with [Cr₇S₈]⁵⁺dicubane cationic clusters, has been synthesized by a low temperature solvothermal method, using dimethyl sulfoxide (DMSO) and ethylenediamine (en) solvents. Ethylenediamine ligand exhibits bi‐ and monodentate coordination modes; in the latter case ethylenediamine coordinates to Cr atoms of adjacent clusters, giving rise to a 2D polymeric structure. Although magnetic susceptibility shows no magnetic ordering down to 1.8 K, a highly negative Weiss constant,θ=−224(2) K, obtained from Curie‐Weiss fit of inverse susceptibility, suggests strong antiferromagnetic (AFM) interactions betweenS=3/2 Cr(III) centers. Due to the complexity of the system with (2S+1)⁷=16384 microstates from seven Cr³⁺centers, a simplified model with only two exchange constants was used for simulations. Density‐functional theory (DFT) calculations yielded the two exchange constants to beJ₁=−21.4 cm⁻¹andJ₂=−30.2 cm⁻¹, confirming competing AFM coupling between the shared Cr³⁺center and the peripheral Cr³⁺ions of the dicubane cluster. The best simulation of the experimental data was obtained withJ₁=−20.0 cm⁻¹andJ₂=−21.0 cm⁻¹, in agreement with the slightly stronger AFM exchange within the triangles of the peripheral Cr³⁺ions as compared to the AFM exchange between the central and peripheral Cr³⁺ions. This compound is proposed as a synthon towards magnetically frustrated systems assembled by linking dicubane transition metal‐chalcogenide clusters into polymeric networks. 

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4. Photoemission from hybrid states of Cl@C ₆₀ before and after a stabilizing charge transfer

   https://doi.org/10.1088/1361-6455/ab82df  

   Shields, Dakota; De, Ruma; Madjet, Mohamed E; Manson, Steven T; Chakraborty, Himadri S (June 2020, Journal of Physics B: Atomic, Molecular and Optical Physics)
5. Anions Formed by Perchlorofluorobenzenes C ₆ Cl _n F _6–n ( n = 0–6)

   https://doi.org/10.1021/acs.jpca.4c04359  

   Sommerfeld, Thomas (September 2024, The Journal of Physical Chemistry A)

   Anions formed by the perhalobenzene series C$$_6$$Cl$$_{n}$$F$$_{6-n}$$ ($n=0-6$) are studied computationally. All members of the series form both stable valence and stable non-valence anions. At the geometry of the neutral parents, only non-valence anions are bound, and the respective vertical electron affinities show values in the $20$ to $60$meV range. Valence anions show distorted non-planar structures, and one can distinguish two types of conformers. A-type conformers show puckered-ring structures and excess electrons delocalized over several C-Cl bonds [in case of C$$_6$$F$$_6^-$$, C-F bonds], while B-type conformers possess excess electrons essentially localized in a single C-Cl bond, which is accordingly strongly stretched and bent out-of-plane. For a specific anion, all conformers are close in energy (relative energies of less than $10$kJ/mol) and are connected by low-lying transition states. Accordingly, A-type and B-type conformers possess similar adiabatic electron affinities, however, their vertical detachment energies exhibit drastically different values, which should ease conformer distinction in photoelectron spectroscopy. 

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