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1. Hysteretic Three-State Redox Interconversion among Zigzag Bisquinodimethanes with Non-fused Benzene Rings and Twisted Tetra-/Dications with [5]/[3]Acenes Exhibiting Near-Infrared Absorptions

Author:
Ishigaki, Yusuke; Harimoto, Takashi; Sugawara, Kazuma; Suzuki, Takanori
Source:
Journal of the American Chemical Society 2021 v.143 no.9 pp. 3306-3311
ISSN:
1520-5126
Subject:
X-radiation,   etc   ; anthracenes; benzene; oxidation;     Show all 4 Subjects
Abstract:
... Octaaryl-substituted bisquinodimethanes (BQDs) with a zigzag structure were designed as redox-switchable molecules that undergo four-electron oxidation to produce tetracationic pentacenes with a doubly twisted structure. In contrast to one-stage four-electron oxidation of BQDs, stepwise two-electron reduction of tetracationic pentacenes occurs to give dicationic anthracenes and then the original B ...
DOI:
10.1021/jacs.1c00189

2. Recapitulating the Binding Affinity of Nrf2 for KEAP1 in a Cyclic Heptapeptide, Guided by NMR, X-ray Crystallography, and Machine Learning

Author:
Ortet, Paula C.; Muellers, Samantha N.; Viarengo-Baker, Lauren A.; Streu, Kristina; Szymczyna, Blair R.; Beeler, Aaron B.; Allen, Karen N.; Whitty, Adrian
Source:
Journal of the American Chemical Society 2021 v.143 no.10 pp. 3779-3793
ISSN:
1520-5126
Subject:
X-radiation,   etc   ; X-ray diffraction; geometry; hydrophobicity; ligands; peptides; proline;     Show all 7 Subjects
Abstract:
... Macrocycles, including macrocyclic peptides, have shown promise for targeting challenging protein–protein interactions (PPIs). One PPI of high interest is between Kelch-like ECH-Associated Protein-1 (KEAP1) and Nuclear Factor (Erythroid-derived 2)-like 2 (Nrf2). Guided by X-ray crystallography, NMR, modeling, and machine learning, we show that the full 20 nM binding affinity of Nrf2 for KEAP1 can ...
DOI:
10.1021/jacs.0c09799

3. Probing the Influence of Defects, Hydration, and Composition on Prussian Blue Analogues with Pressure

Author:
Boström, Hanna L. B.; Collings, Ines E.; Daisenberger, Dominik; Ridley, Christopher J.; Funnell, Nicholas P.; Cairns, Andrew B.
Source:
Journal of the American Chemical Society 2021 v.143 no.9 pp. 3544-3554
ISSN:
1520-5126
Subject:
X-radiation,   etc   ; cations; compressibility; neutron diffraction; phase transition; stoichiometry;     Show all 6 Subjects
Abstract:
... The vast compositional space of Prussian blue analogues (PBAs), formula AₓM[M′(CN)₆]y·nH₂O, allows for a diverse range of functionality. Yet, the interplay between composition and physical properties—e.g., flexibility and propensity for phase transitions—is still largely unknown, despite its fundamental and industrial relevance. Here we use variable-pressure X-ray and neutron diffraction to explor ...
DOI:
10.1021/jacs.0c13181

4. Pressure Induced Assembly and Coalescence of Lead Chalcogenide Nanocrystals

Author:
Meng, Lingyao; Duwal, Sakun; Lane, J. Matthew D.; Ao, Tommy; Stoltzfus, Brian; Knudson, Marcus; Park, Changyong; Chow, Paul; Xiao, Yuming; Fan, Hongyou; Qin, Yang
Source:
Journal of the American Chemical Society 2021 v.143 no.7 pp. 2688-2693
ISSN:
1520-5126
Subject:
X-radiation,   etc   ; lead; nanocrystals; nanorods; nanosheets; semiconductors; transmission electron microscopy;     Show all 7 Subjects
Abstract:
... We report here pressure induced nanocrystal coalescence of ordered lead chalcogenide nanocrystal arrays into one-dimensional (1D) and 2D nanostructures. In particular, atomic crystal phase transitions and mesoscale coalescence of PbS and PbSe nanocrystals have been observed and monitored in situ respectively by wide- and small-angle synchrotron X-ray scattering techniques. At the atomic scale, bot ...
DOI:
10.1021/jacs.0c13350

5. Reductive C–C Coupling from Molecular Au(I) Hydrocarbyl Complexes: A Mechanistic Study

Author:
Miranda-Pizarro, Juan; Luo, Zhongwen; Moreno, Juan J.; Dickie, Diane A.; Campos, Jesús; Gunnoe, T. Brent
Source:
Journal of the American Chemical Society 2021 v.143 no.6 pp. 2509-2522
ISSN:
1520-5126
Subject:
X-radiation,   etc   ; catalysts; ethane; gold; nuclear magnetic resonance spectroscopy; phosphine;     Show all 6 Subjects
Abstract:
... Organometallic gold complexes are used in a range of catalytic reactions, and they often serve as catalyst precursors that mediate C–C bond formation. In this study, we investigate C–C coupling to form ethane from various phosphine-ligated gem-digold(I) methyl complexes including [Au₂(μ-CH₃)(PMe₂Ar′)₂][NTf₂], [Au₂(μ-CH₃)(XPhos)₂][NTf₂], and [Au₂(μ-CH₃)(ᵗBuXPhos)₂][NTf₂] {Ar′ = C₆H₃-2,6-(C₆H₃-2,6-M ...
DOI:
10.1021/jacs.0c11296

6. A Curved Graphene Nanoribbon with Multi-Edge Structure and High Intrinsic Charge Carrier Mobility

Author:
Niu, Wenhui; Ma, Ji; Soltani, Paniz; Zheng, Wenhao; Liu, Fupin; Popov, Alexey A.; Weigand, Jan J.; Komber, Hartmut; Poliani, Emanuele; Casiraghi, Cinzia; Droste, Jörn; Hansen, Michael Ryan; Osella, Silvio; Beljonne, David; Bonn, Mischa; Wang, Hai I.; Feng, Xinliang; Liu, Junzhi; Mai, Yiyong
Source:
Journal of the American Chemical Society 2020 v.142 no.43 pp. 18293-18298
ISSN:
1520-5126
Subject:
X-radiation,   etc   ; absorption; energy; graphene;     Show all 4 Subjects
Abstract:
... Structurally well-defined graphene nanoribbons (GNRs) have emerged as highly promising materials for the next-generation nanoelectronics. The electronic properties of GNRs critically depend on their edge topologies. Here, we demonstrate the efficient synthesis of a curved GNR (cGNR) with a combined cove, zigzag, and armchair edge structure, through bottom-up synthesis. The curvature of the cGNR is ...
DOI:
10.1021/jacs.0c07013

7. Boronate Ester Bullvalenes

Author:
Patel, Harshal D.; Tran, Thanh-Huyen; Sumby, Christopher J.; Pašteka, Lukáš F.; Fallon, Thomas
Source:
Journal of the American Chemical Society 2020 v.142 no.8 pp. 3680-3685
ISSN:
1520-5126
Subject:
X-radiation,   etc   ; Suzuki reaction; isomers;     Show all 3 Subjects
Abstract:
... Boronate ester bullvalenes are now accessible in two to four operationally simple steps. This unlocks late-stage diversification through Suzuki cross-coupling reactions to give mono-, di-, and trisubstituted bullvalenes. Moreover, a linchpin strategy enables preprogrammed installation of two different substituents. Analysis of solution phase isomer distributions and single-crystal X-ray structures ...
DOI:
10.1021/jacs.9b12930

8. Electrochemical Oxidation Enables Regioselective and Scalable α-C(sp³)-H Acyloxylation of Sulfides

Author:
Wang, Huamin; He, Meng; Li, Yongli; Zhang, Heng; Yang, Dali; Nagasaka, Masanari; Lv, Zongchao; Guan, Zhipeng; Cao, Yangmin; Gong, Fengping; Zhou, Zhilin; Zhu, Jingyun; Samanta, Supravat; Chowdhury, Abhishek Dutta; Lei, Aiwen
Source:
Journal of the American Chemical Society 2021 v.143 no.9 pp. 3628-3637
ISSN:
1520-5126
Subject:
X-radiation,   etc   ; Lewis bases; absorption; cross-coupling reactions; electrochemistry; oxidation; regioselectivity; synergism;     Show all 8 Subjects
Abstract:
... A highly selective, environmentally friendly, and scalable electrochemical protocol for the construction of α-acyloxy sulfides, through the synergistic effect of self-assembly-induced C(sp³)–H/O–H cross-coupling, is reported. It features exceptionally broad substrate scope, high regioselectivity, gram-scale synthesis, construction of complex molecules, and applicability to a variety of nucleophile ...
DOI:
10.1021/jacs.1c00288

9. Structural Characterization of the [CuOR]²⁺ Core

Author:
Krishnan, V. Mahesh; Shopov, Dimitar Y.; Bouchey, Caitlin J.; Bailey, Wilson D.; Parveen, Riffat; Vlaisavljevich, Bess; Tolman, William B.
Source:
Journal of the American Chemical Society 2021 v.143 no.9 pp. 3295-3299
ISSN:
1520-5126
Subject:
X-radiation,   etc   ; X-ray diffraction; ligands; nuclear magnetic resonance spectroscopy; phenol;     Show all 5 Subjects
Abstract:
... Formal Cu(III) complexes bearing an oxygen-based auxiliary ligand ([CuOR]²⁺, R = H or CH₂CF₃) were stabilized by modulating the donor character of supporting ligand LY (LY = 4-Y, N,N′-bis(2,6-diisopropylphenyl)-2,6-pyridinedicarboxamide, Y = H or OMe) and/or the basicity of the auxiliary ligand, enabling the first characterization of these typically highly reactive cores by NMR spectroscopy and X- ...
DOI:
10.1021/jacs.0c13470

10. Nanoparticle O–H Bond Dissociation Free Energies from Equilibrium Measurements of Cerium Oxide Colloids

Author:
Agarwal, Rishi G.; Kim, Hyun-Jo; Mayer, James M.
Source:
Journal of the American Chemical Society 2021 v.143 no.7 pp. 2896-2907
ISSN:
1520-5126
Subject:
X-radiation,   etc   ; ; Gibbs free energy; absorption; catalysts; catalytic activity; ceric oxide; dissociation; electron transfer; hydrogen; nanoceria;     Show all 11 Subjects
Abstract:
... A novel equilibrium strategy for measuring the hydrogen atom affinity of colloidal metal oxide nanoparticles is presented. Reactions between oleate-capped cerium oxide nanoparticle colloids (nanoceria) and organic proton-coupled electron transfer (PCET) reagents are used as a model system. Nanoceria redox changes, or hydrogen loadings, and overall reaction stoichiometries were followed by both ¹H ...
DOI:
10.1021/jacs.0c12799

11. Demonstration of Energy-Resolved γ-Ray Detection at Room Temperature by the CsPbCl₃ Perovskite Semiconductor

Author:
He, Yihui; Stoumpos, Constantinos C.; Hadar, Ido; Luo, Zhongzhen; McCall, Kyle M.; Liu, Zhifu; Chung, Duck Young; Wessels, Bruce W.; Kanatzidis, Mercouri G.
Source:
Journal of the American Chemical Society 2021 v.143 no.4 pp. 2068-2077
ISSN:
1520-5126
Subject:
X-radiation,   etc   ; air; ambient temperature; electrical resistance; energy; semiconductors; spectroscopy; thermal conductivity;     Show all 8 Subjects
Abstract:
... The detection of γ-rays at room temperature with high-energy resolution using semiconductors is one of the most challenging applications. The presence of even the smallest amount of defects is sufficient to kill the signal generated from γ-rays which makes the availability of semiconductors detectors a rarity. Lead halide perovskite semiconductors exhibit unusually high defect tolerance leading to ...
DOI:
10.1021/jacs.0c12254

12. Guest-Binding-Induced Interhetero Hosts Charge Transfer Crystallization: Selective Coloration of Commonly Used Organic Solvents

Author:
Mi, Yan; Ma, Jingyu; Liang, Wenting; Xiao, Chao; Wu, Wanhua; Zhou, Dayang; Yao, Jiabin; Sun, Wenjia; Sun, Junliang; Gao, Guowei; Chen, Xiaochuan; Chruma, Jason J.; Yang, Cheng
Source:
Journal of the American Chemical Society 2021 v.143 no.3 pp. 1553-1561
ISSN:
1520-5126
Subject:
X-radiation,   etc   ; X-ray diffraction; absorption; aromatic hydrocarbons; benzoquinones; color; crystallization; electron microscopy; solvents;     Show all 9 Subjects
Abstract:
... Unprecedented interheteromacrocyclic hosts charge transfer (CT) crystals were generated by cooling organic solutions containing p-dimethoxybenzene-constituted pillar[5]arene (P5A) and p-benzoquinone-constituted pillar[5]quinone (P5Q). Despite the weak CT interaction known between p-dimethoxybenzene and p-benzoquinone and the lack of formation of CT complexes between P5A and P5Q in the solution pha ...
DOI:
10.1021/jacs.0c11833

13. Dialkyl Ether Formation at High-Valent Nickel

Author:
Le Vaillant, Franck; Reijerse, Edward J.; Leutzsch, Markus; Cornella, Josep
Source:
Journal of the American Chemical Society 2020 v.142 no.46 pp. 19540-19550
ISSN:
1520-5126
Subject:
X-radiation,   etc   ; alcohols; ethyl ether; nickel;     Show all 4 Subjects
Abstract:
... In this article, we investigated the I₂-promoted cyclic dialkyl ether formation from 6-membered oxanickelacycles originally reported by Hillhouse. A detailed mechanistic investigation based on spectroscopic and crystallographic analysis revealed that a putative reductive elimination to forge C(sp³)–OC(sp³) using I₂ might not be operative. We isolated a paramagnetic bimetallic Niᴵᴵᴵ intermediate fe ...
DOI:
10.1021/jacs.0c07381

14. Synthesis, Assembly, and Sizing of Neutral, Lanthanide Substituted Molybdenum Blue Wheels {Mo₉₀Ln₁₀}

Author:
Garrido Ribó, Eduard; Bell, Nicola L.; Xuan, Weimin; Luo, Jiancheng; Long, De-Liang; Liu, Tianbo; Cronin, Leroy
Source:
Journal of the American Chemical Society 2020 v.142 no.41 pp. 17508-17514
ISSN:
1520-5126
Subject:
X-radiation,   etc   ; lanthanides; molybdates; molybdenum; solubility; temperature;     Show all 6 Subjects
Abstract:
... Polyoxometalate molybdenum blue (MB) complexes typically exist as discrete multianionic clusters and are composed of repeating Mo building units. MB wheels such as {Mo₁₇₆} and {Mo₁₅₄} are made from pentagon-centered {Mo₈} building blocks joined by equal number of {Mo₁} units as loin, and {Mo₂} dimer units as skirt along the ring edge, with the ring sizes of the MB wheels modulated by the {Mo₂} uni ...
DOI:
10.1021/jacs.0c07146

15. Compensation of Hybridization Defects in Phosphorescent Complexes with Pnictogen-Based Ligands—A Structural, Photophysical, and Theoretical Case-Study with Predictive Character

Author:
Gangadharappa, Sathish Chatnahalli; Maisuls, Iván; Schwab, Dominik A.; Kösters, Jutta; Doltsinis, Nikos L.; Strassert, Cristian A.
Source:
Journal of the American Chemical Society 2020 v.142 no.51 pp. 21353-21367
ISSN:
1520-5126
Subject:
X-radiation,   etc   ; geometry; hybridization; ligands; phosphorescence; pyridines; spectroscopy; triazoles;     Show all 8 Subjects
Abstract:
... In this work, for the first time, the comparative use of P-, As-, and Sb-based ligands in phosphorescent coordination compounds is reported toward new coordination chemical concepts in the design and realization of tailored triplet emitters with nonconventional elements. By means of spectroscopic, X-ray diffractometric, and quantum-chemical methods, we reconstructed the nature of the chemical bond ...
DOI:
10.1021/jacs.0c09467

16. Symmetry-Breaking Charge Separation in the Solid State: Tetra(phenoxy)perylenediimide Polycrystalline Films

Author:
Ramirez, Carolyn E.; Chen, Su; Powers-Riggs, Natalia E.; Schlesinger, Itai; Young, Ryan M.; Wasielewski, Michael R.
Source:
Journal of the American Chemical Society 2020 v.142 no.42 pp. 18243-18250
ISSN:
1520-5126
Subject:
X-radiation,   etc   ; electric potential difference; hydrogen; nitrogen; solar energy; spectroscopy;     Show all 6 Subjects
Abstract:
... Generation of electron–hole pairs via symmetry-breaking charge separation (SB-CS) in photoexcited assemblies of organic chromophores is a potentially important route to enhancing the open-circuit voltage of organic photovoltaics. While most reports of SB-CS have focused on molecular dimers in solution where the environmental polarity can be manipulated, here, we investigate SB-CS in polycrystallin ...
DOI:
10.1021/jacs.0c09185

17. Influenza A M2 Inhibitor Binding Understood through Mechanisms of Excess Proton Stabilization and Channel Dynamics

Author:
Watkins, Laura C.; DeGrado, William F.; Voth, Gregory A.
Source:
Journal of the American Chemical Society 2020 v.142 no.41 pp. 17425-17433
ISSN:
1520-5126
Subject:
X-radiation,   etc   ; ammonium; drug design; drugs; influenza; molecular dynamics;     Show all 6 Subjects
Abstract:
... Prevalent resistance to inhibitors that target the influenza A M2 proton channel has necessitated a continued drug design effort, supported by a sustained study of the mechanism of channel function and inhibition. Recent high-resolution X-ray crystal structures present the first opportunity to see how the adamantyl amine class of inhibitors bind to M2 and disrupt and interact with the channel’s wa ...
DOI:
10.1021/jacs.0c06419

18. All-Photochemical Rotation of Molecular Motors with a Phosphorus Stereoelement

Author:
Boursalian, Gregory B.; Nijboer, Eise R.; Dorel, Ruth; Pfeifer, Lukas; Markovitch, Omer; Blokhuis, Alex; Feringa, Ben L.
Source:
Journal of the American Chemical Society 2020 v.142 no.39 pp. 16868-16876
ISSN:
1520-5126
Subject:
X-radiation,   etc   ; alkenes; kinetics; optical isomerism; phosphine; phosphorus; photochemistry;     Show all 7 Subjects
Abstract:
... Unidirectional molecular rotation based on alternating photochemical and thermal isomerizations of overcrowded alkenes is well established, but rotary cycles based purely on photochemical isomerizations are rare. Herein we report three new second-generation molecular motors featuring a phosphorus center in the lower half, which engenders a unique element of axial chirality. These motors exhibit un ...
DOI:
10.1021/jacs.0c08249

19. Three-Dimensional Polycatenation of a Uranium-Based Metal–Organic Cage: Structural Complexity and Radiation Detection

Author:
Cheng, Liwei; Liang, Chengyu; Liu, Wei; Wang, Yaxing; Chen, Bin; Zhang, Hailong; Wang, Yanlong; Chai, Zhifang; Wang, Shuao
Source:
Journal of the American Chemical Society 2020 v.142 no.38 pp. 16218-16222
ISSN:
1520-5126
Subject:
X-radiation,   etc   ; electric current; electron transfer; ligands; uranyl ions;     Show all 5 Subjects
Abstract:
... The potential applications of metal–organic cages (MOCs) are mostly achieved through specific host–guest interactions within their cavities. Electronic applications would require an effective electron transport pathway, which has been extensively studied in hybrid organic–inorganic materials with extended structures. These properties have not been considered for MOCs because cage-to-cage interacti ...
DOI:
10.1021/jacs.0c08117

20. From a (Silatrigerma)cyclobutenylium Ion to a (Silatrigerma)cyclobutenyl Radical and Back

Author:
Lee, Vladimir Ya.; Ito, Yuki; Gapurenko, Olga A.; Minyaev, Ruslan M.; Gornitzka, Heinz; Sekiguchi, Akira
Source:
Journal of the American Chemical Society 2020 v.142 no.38 pp. 16455-16460
ISSN:
1520-5126
Subject:
X-radiation,   etc   ; benzene; cations; free radicals; graphene; potassium;     Show all 6 Subjects
Abstract:
... (Silatrigerma)cyclobutenylium ion salt 2⁺·[B(C₆F₅)₄]– was readily prepared by the reaction of cyclotrigermene 1 with an equimolar amount of [Et₃Si(benzene)]⁺·[B(C₆F₅)₄]⁻ in benzene. The homoaromatic nature of 2⁺ was firmly established by its crystallographic analysis, which revealed a highly folded SiGe₃ four-membered ring (40.4°) and a remarkably short transannular Ge–Ge distance of 2.9346(3) Å. ...
DOI:
10.1021/jacs.0c08052