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1. Characterization of Light-Induced, Short-Lived Interacting Radicals in the Active Site of Flavoprotein Ferredoxin-NADP⁺ Oxidoreductase

Author:
Zhuang, Bo; Seo, Daisuke; Aleksandrov, Alexey; Vos, Marten H.
Source:
Journal of the American Chemical Society 2021 v.143 no.7 pp. 2757-2768
ISSN:
1520-5126
Subject:
Bacillus subtilis; absorption; active sites; electron transfer; enzymes; flavin-adenine dinucleotide; flavoproteins; fluorescence; molecular dynamics; mutants; quantum mechanics; spectroscopy; tryptophan; tyrosine
Abstract:
... Radicals of flavin adenine dinucleotide (FAD), as well as tyrosine and tryptophan, are widely involved as key reactive intermediates during electron-transfer (ET) reactions in flavoproteins. Due to the high reactivity of these species and their corresponding short lifetime, characterization of these intermediates in functional processes of flavoproteins is usually challenging but can be achieved b ...
DOI:
10.1021/jacs.0c09627

2. Electroless Formation of a Fluorinated Li/Na Hybrid Interphase for Robust Lithium Anodes

Author:
Wang, Yingli; Liu, Fangming; Fan, Guilan; Qiu, Xiaoguang; Liu, Jiuding; Yan, Zhenhua; Zhang, Kai; Cheng, Fangyi; Chen, Jun
Source:
Journal of the American Chemical Society 2021 v.143 no.7 pp. 2829-2837
ISSN:
1520-5126
Subject:
anodes; cathodes; electrolytes; interphase; lithium; sodium; strength (mechanics)
Abstract:
... Engineering a stable solid electrolyte interphase (SEI) is one of the critical maneuvers in improving the performance of a lithium anode for high-energy-density rechargeable lithium batteries. Herein, we build a fluorinated lithium/sodium hybrid interphase via a facile electroless electrolyte-soaking approach to stabilize the repeated plating/stripping of lithium metal. Jointed experimental and co ...
DOI:
10.1021/jacs.0c12051

3. Electronic Relaxation Pathways in Heavy-Atom-Free Photosensitizers Absorbing Near-Infrared Radiation and Exhibiting High Yields of Singlet Oxygen Generation

Author:
Ortiz-Rodríguez, Luis A.; Hoehn, Sean J.; Loredo, Axel; Wang, Lushun; Xiao, Han; Crespo-Hernández, Carlos E.
Source:
Journal of the American Chemical Society 2021 v.143 no.7 pp. 2676-2681
ISSN:
1520-5126
Subject:
near infrared radiation; photocatalysis; photochemotherapy; photons; singlet oxygen; solar energy
Abstract:
... Heavy-atom-free photosensitizers (HAF-PSs) based on thionation of carbonyl groups of readily accessible organic compounds are rapidly emerging as a versatile class of molecules. However, their photochemical properties and electronic relaxation mechanisms are currently unknown. Investigating the excited-state dynamics is essential to understand their benefits and limitations and to develop photosen ...
DOI:
10.1021/jacs.0c13203

4. Enantioselective Total Synthesis of (+)-Stephadiamine through Bioinspired Aza-Benzilic Acid Type Rearrangement

Author:
Odagi, Minami; Matoba, Taisei; Hosoya, Keisuke; Nagasawa, Kazuo
Source:
Journal of the American Chemical Society 2021 v.143 no.7 pp. 2699-2704
ISSN:
1520-5126
Subject:
alkaloids; biochemical pathways; chemical reactions; diastereoselectivity; enantioselectivity; regioselectivity
Abstract:
... We report the first enantioselective total syntheses of the hasubanan alkaloid (−)-metaphanine and the norhasubanan alkaloid (+)-stephadiamine. Key features of these syntheses include diastereoselective oxidative phenolic coupling reaction and subsequent regioselective intramolecular aza-Michael reaction, which efficiently construct the hasubanan skeleton with the all-carbon quaternary stereogenic ...
DOI:
10.1021/jacs.1c00047

5. Transient Imine as a Directing Group for the Metal-Free o-C–H Borylation of Benzaldehydes

Author:
Rej, Supriya; Chatani, Naoto
Source:
Journal of the American Chemical Society 2021 v.143 no.7 pp. 2920-2929
ISSN:
1520-5126
Subject:
benzaldehyde; imines; moieties; organic chemistry
Abstract:
... Organoboron reagents are important synthetic intermediates and have wide applications in synthetic organic chemistry. The selective borylation strategies that are currently in use largely rely on the use of transition-metal catalysts. Hence, identifying much milder conditions for transition-metal-free borylation would be highly desirable. We herein present a unified strategy for the selective C–H ...
DOI:
10.1021/jacs.0c13013

6. Anthracene–Triphenylamine-Based Platinum(II) Metallacages as Synthetic Light-Harvesting Assembly

Author:
Li, Yanrong; Rajasree, Sreehari Surendran; Lee, Ga Young; Yu, Jierui; Tang, Jian-Hong; Ni, Ruidong; Li, Guigen; Houk, Kendall. N.; Deria, Pravas; Stang, Peter J.
Source:
Journal of the American Chemical Society 2021 v.143 no.7 pp. 2908-2919
ISSN:
1520-5126
Subject:
absorptivity; anthracenes; dicarboxylic acids; dimethyl sulfoxide; energy transfer; fluorescent dyes; ligands; platinum; solvents; temperature
Abstract:
... Two trigonal prismatic metallacages 1 and 2 bearing triphenylamine and anthracene moieties are designed and synthesized to fabricate artificial light-harvesting systems (LHSs). These two cages are prepared via the coordination-driven self-assembly of two anthracene–triphenylamine-based tripyridyl ligand 3, three dicarboxylates, and six 90° Pt(II) acceptors. The design of the anthracene–triphenylam ...
DOI:
10.1021/jacs.0c12853

7. Copper Catalyzed C(sp³)–H Bond Alkylation via Photoinduced Ligand-to-Metal Charge Transfer

Author:
Treacy, Sean M.; Rovis, Tomislav
Source:
Journal of the American Chemical Society 2021 v.143 no.7 pp. 2729-2735
ISSN:
1520-5126
Subject:
alkenes; alkylation; catalysts; chlorine; diastereoselectivity; hydrogen; oxidants
Abstract:
... Utilizing catalytic CuCl₂ we report the functionalization of numerous feedstock chemicals via the coupling of unactivated C(sp³)–H bonds with electron-deficient olefins. The active cuprate catalyst undergoes Ligand-to-Metal Charge Transfer (LMCT) to enable the generation of a chlorine radical which acts as a powerful hydrogen atom transfer reagent capable of abstracting strong electron-rich C(sp³) ...
DOI:
10.1021/jacs.1c00687

8. Helicene-Based Ligands Enable Strong Magneto-Chiral Dichroism in a Chiral Ytterbium Complex

Author:
Atzori, Matteo; Dhbaibi, Kais; Douib, Haiet; Grasser, Maxime; Dorcet, Vincent; Breslavetz, Ivan; Paillot, Kévin; Cador, Olivier; Rikken, Geert L. J. A.; Le Guennic, Boris; Crassous, Jeanne; Pointillart, Fabrice; Train, Cyrille
Source:
Journal of the American Chemical Society 2021 v.143 no.7 pp. 2671-2675
ISSN:
1520-5126
Subject:
absorption; enantiomers; ligands; magnetic fields; optical isomerism; temperature; ytterbium
Abstract:
... Here we report the first experimental observation of magneto-chiral dichroism (MChD) detected through light absorption in an enantiopure lanthanide complex. The P and M enantiomers of [Ybᴵᴵᴵ((X)-L)(hfac)₃] (X = P, M; L = 3-(2-pyridyl)-4-aza[6]-helicene; hfac = 1,1,1,5,5,5-hexafluoroacetylacetonate), where the chirality is held by the helicene-based ligand, were studied in the near-infrared spectra ...
DOI:
10.1021/jacs.0c13180

9. 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; lead; nanocrystals; nanorods; nanosheets; semiconductors; transmission electron microscopy
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

10. Probing N-Glycan Functions in Human Interleukin-17A Based on Chemically Synthesized Homogeneous Glycoforms

Author:
Li, Hongxing; Zhang, Jun; An, Chuanjing; Dong, Suwei
Source:
Journal of the American Chemical Society 2021 v.143 no.7 pp. 2846-2856
ISSN:
1520-5126
Subject:
deuterium; dose response; fibroblasts; glycoproteins; glycosylation; humans; interleukin-17; polysaccharides; spectroscopy; structure-activity relationships; surface plasmon resonance; viability
Abstract:
... N-Glycosylation represents an essential type of posttranslational modification for proteins. However, deciphering the functions of N-glycosylation remains a challenge due to the lack of analytical and biochemical methods to accurately differentiate the protein glycoforms with various intact glycans. Here we report our synthesis and evaluation of homogeneously glycosylated interleukin-17A (IL-17A), ...
DOI:
10.1021/jacs.0c12448

11. Reconstitution of a Highly Reducing Type II PKS System Reveals 6π-Electrocyclization Is Required for o-Dialkylbenzene Biosynthesis

Author:
Zhang, Jie; Yuzawa, Satoshi; Thong, Wei Li; Shinada, Tetsuro; Nishiyama, Makoto; Kuzuyama, Tomohisa
Source:
Journal of the American Chemical Society 2021 v.143 no.7 pp. 2962-2969
ISSN:
1520-5126
Subject:
Streptomyces; acyl carrier protein; biochemical pathways; bioinformatics; biosynthesis; dehydrogenation; isomerases; isomerization; moieties; multigene family; polyketide synthases
Abstract:
... Natural products containing an o-dialkylbenzene moiety exhibit a wide variety of bioactivities, including antibacterial, antifungal, antitumor, and antiangiogenic activities. However, the biosynthetic scheme of the o-dialkylbenzene moiety remains unclear. In this study, we identified the biosynthetic gene cluster (BGC) of compounds 1 and 2 in Streptomyces sp. SANK 60404, which contains a rare o-di ...
DOI:
10.1021/jacs.0c13378

12. Screening of DNA-Encoded Small Molecule Libraries inside a Living Cell

Author:
Petersen, Lars K.; Christensen, Allan B.; Andersen, Jacob; Folkesson, Charlotta G.; Kristensen, Ole; Andersen, Charlotte; Alzu, Amaya; Sløk, Frank A.; Blakskjær, Peter; Madsen, Daniel; Azevedo, Carlos; Micco, Iolanda; Hansen, Nils J. V.
Source:
Journal of the American Chemical Society 2021 v.143 no.7 pp. 2751-2756
ISSN:
1520-5126
Subject:
DNA; Xenopus laevis; oocytes; somatic cells; therapeutics
Abstract:
... DNA-encoded small molecule libraries (DELs) have facilitated the discovery of novel modulators of many different therapeutic protein targets. We report the first successful screening of a multimillion membered DEL inside a living cell. We demonstrate a novel method using oocytes from the South African clawed frog Xenopus laevis. The large size of the oocytes of 1 μL, or 100 000 times bigger than a ...
DOI:
10.1021/jacs.0c09213

13. Total Synthesis of the Cephalotaxus Norditerpenoids (±)-Cephanolides A–D

Author:
Haider, Maximilian; Sennari, Goh; Eggert, Alina; Sarpong, Richmond
Source:
Journal of the American Chemical Society 2021 v.143 no.7 pp. 2710-2715
ISSN:
1520-5126
Subject:
Cephalotaxus; carbon; cross-coupling reactions; cycloaddition reactions; diterpenoids
Abstract:
... Concise syntheses of the Cephalotaxus norditerpenoids cephanolides A–D (8–14 steps from commercial material) using a common late-stage synthetic intermediate are described. The success of our approach rested on an early decision to apply chemical network analysis to identify the strategic bonds that needed to be forged, as well as the efficient construction of the carbon framework through iterativ ...
DOI:
10.1021/jacs.1c00293

14. Biosynthetic Functionalization of Nonribosomal Peptides

Author:
Niquille, David L.; Folger, Ines B.; Basler, Sophie; Hilvert, Donald
Source:
Journal of the American Chemical Society 2021 v.143 no.7 pp. 2736-2740
ISSN:
1520-5126
Subject:
alkynes; biosynthesis; cycloaddition reactions; fluorescence; halogens; ligases; nonribosomal peptides; point mutation; synthetic biology; therapeutics; tyrocidine
Abstract:
... Nonribosomal peptides (NRPs) are a therapeutically important class of secondary metabolites that are produced by modular synthetases in assembly-line fashion. We previously showed that a single Trp-to-Ser mutation in the initial Phe-loading adenylation domain of tyrocidine synthetase completely switches the specificity toward clickable analogues. Here we report that this minimally invasive strateg ...
DOI:
10.1021/jacs.1c00925

15. Evolution of a Synthetic Strategy for Complex Polypyrrole Alkaloids: Total Syntheses of Curvulamine and Curindolizine

Author:
Xuan, Jun; Haelsig, Karl T.; Sheremet, Michael; Machicao, Paulo A.; Maimone, Thomas J.
Source:
Journal of the American Chemical Society 2021 v.143 no.7 pp. 2970-2983
ISSN:
1520-5126
Subject:
Bipolaris maydis; Curvularia; Lewis bases; alkaloids; biomimetics; biosynthesis; decarboxylation; evolution; metabolites; pyrroles
Abstract:
... Structurally unprecedented antibacterial alkaloids containing multiple electron-rich pyrrole units have recently been isolated from Curvularia sp. and Bipolaris maydis fungi. This article documents the evolution of a synthetic program aimed at accessing the flagship metabolites curvulamine and curindolizine which are presumably a dimer and trimer of a C₁₀N biosynthetic building block, respectively ...
DOI:
10.1021/jacs.0c13465

16. Network-Forming Liquids from Metal–Bis(acetamide) Frameworks with Low Melting Temperatures

Author:
Liu, Mengtan; McGillicuddy, Ryan D.; Vuong, Hung; Tao, Songsheng; Slavney, Adam H.; Gonzalez, Miguel I.; Billinge, Simon J. L.; Mason, Jarad A.
Source:
Journal of the American Chemical Society 2021 v.143 no.7 pp. 2801-2811
ISSN:
1520-5126
Subject:
X-ray absorption spectroscopy; calorimetry; crystallography; enthalpy; entropy; hydrogen; ligands; liquids; temperature
Abstract:
... Molten phases of metal–organic networks offer exciting opportunities for using coordination chemistry principles to access liquids and glasses with unique and tunable structures and properties. Here, we discuss general thermodynamic strategies to provide an increased enthalpic and entropic driving force for reversible, low-temperature melting transitions in extended coordination solids and illustr ...
DOI:
10.1021/jacs.0c11718

17. Photocatalytic C–C Coupling from Carbon Dioxide Reduction on Copper Oxide with Mixed-Valence Copper(I)/Copper(II)

Author:
Wang, Wei; Deng, Chaoyuan; Xie, Shijie; Li, Yangfan; Zhang, Wanyi; Sheng, Hua; Chen, Chuncheng; Zhao, Jincai
Source:
Journal of the American Chemical Society 2021 v.143 no.7 pp. 2984-2993
ISSN:
1520-5126
Subject:
X-ray absorption spectroscopy; active sites; carbon dioxide; cupric oxide; lighting; photocatalysis; photocatalysts; triethylamine
Abstract:
... To realize the evolution of C₂₊ hydrocarbons like C₂H₄ from CO₂ reduction in photocatalytic systems remains a great challenge, owing to the gap between the relatively lower efficiency of multielectron transfer in photocatalysis and the sluggish kinetics of C–C coupling. Herein, with Cu-doped zeolitic imidazolate framework-8 (ZIF-8) as a precursor, a hybrid photocatalyst (CuOX@p-ZnO) with CuOX unif ...
DOI:
10.1021/jacs.1c00206

18. Photocatalytic Oxidative Coupling of Arylamines for the Synthesis of Azoaromatics and the Role of O₂ in the Mechanism

Author:
Sitter, James D.; Vannucci, Aaron K.
Source:
Journal of the American Chemical Society 2021 v.143 no.7 pp. 2938-2943
ISSN:
1520-5126
Subject:
air; fluorescence; oxidation; oxygen; photocatalysis; photocatalysts; pyridines
Abstract:
... The photocatalytic oxidative coupling of aryl amines to selectively synthesize azoaromatic compounds has been realized. Multiple different photocatalysts can be used to perform the general reaction; however, Ir(dF-CF₃-ppy)₂(dtbpy)⁺, where dF-CF₃-ppy is 2-(2,4-difluorophenyl)-5-(trifluoromethyl)pyridine and dtpby is 4,4′-tert-butyl-2,2′-bipyridine, showed the greatest range of reactivity with vario ...
DOI:
10.1021/jacs.0c13101

19. Scandium-Terminal Boronylphosphinidene Complex

Author:
Feng, Bin; Xiang, Li; Carpentier, Ambre; Maron, Laurent; Leng, Xuebing; Chen, Yaofeng
Source:
Journal of the American Chemical Society 2021 v.143 no.7 pp. 2705-2709
ISSN:
1520-5126
Subject:
Lewis bases; X-ray diffraction; scandium
Abstract:
... The first isolation and structural characterization of a rare-earth metal-terminal imido complex were reported in 2010, but a rare-earth metal-terminal phosphinidene complex is still absent, to date. Herein, we report the synthesis and structure of the first example of a rare-earth-terminal phosphinidene complex, namely the scandium boronylphosphinidene complex. Single-crystal X-ray diffraction sh ...
DOI:
10.1021/jacs.1c00148

20. Selective CO₂ Electrochemical Reduction Enabled by a Tricomponent Copolymer Modifier on a Copper Surface

Author:
Wang, Jianchun; Cheng, Tao; Fenwick, Aidan Q.; Baroud, Turki N.; Rosas-Hernández, Alonso; Ko, Jeong Hoon; Gan, Quan; Goddard III, William A.; Grubbs, Robert H.
Source:
Journal of the American Chemical Society 2021 v.143 no.7 pp. 2857-2865
ISSN:
1520-5126
Subject:
carbon dioxide; composite polymers; delamination; electric field; electrochemistry; electrodes; ethylene; foil; molecular dynamics; polymerization; porosity; value added
Abstract:
... Electrochemical CO₂ reduction over Cu could provide value-added multicarbon hydrocarbons and alcohols. Despite recent breakthroughs, it remains a significant challenge to design a catalytic system with high product selectivity. Here we demonstrate that a high selectivity of ethylene (55%) and C₂₊ products (77%) could be achieved by a highly modular tricomponent copolymer modified Cu electrode, riv ...
DOI:
10.1021/jacs.0c12478