Chiral Materials: Progress, Applications, and Prospects

Small, Journal Year: 2023, Volume and Issue: 19(38)

Published: May 22, 2023

Abstract Chirality is a universal phenomenon in molecular and biological systems, denoting an asymmetric configurational property where object cannot be superimposed onto its mirror image by any kind of translation or rotation, which ubiquitous on the scale from neutrinos to spiral galaxies. plays very important role life system. Many molecules body show chirality, such as “codebook” earth's diversity‐DNA, nucleic acid, etc. Intriguingly, living organisms hierarchically consist homochiral building blocks, for example, l ‐amino acids d ‐sugars with unknown reason. When chirality interact these chiral factors, only one conformation favors positive development life, that is, host environment can selectively conformations. The differences interactions are often manifested recognition, mutual matching, molecules, means stereoselectivity produce changes pharmacodynamics pathology. Here, latest investigations summarized including construction applications materials based natural small source, biomacromolecules sources, material synthesized design source.

Language: Английский

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A machine-learning tool to predict substrate-adaptive conditions for Pd-catalyzed C–N couplings

Science, Journal Year: 2023, Volume and Issue: 381(6661), P. 965 - 972

Published: Aug. 31, 2023

Machine-learning methods have great potential to accelerate the identification of reaction conditions for chemical transformations. A tool that gives substrate-adaptive palladium (Pd)-catalyzed carbon-nitrogen (C-N) couplings is presented. The design and construction this required generation an experimental dataset explores a diverse network reactant pairings across set conditions. large scope C-N was actively learned by neural models using systematic process experiments. showed good performance in validation: Ten products were isolated more than 85% yield from range with out-of-sample reactants designed challenge models. Importantly, developed workflow continually improves prediction capability as corpus data grows.

Language: Английский

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Mechanisms of Photoredox Catalysis Featuring Nickel–Bipyridine Complexes

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(11), P. 9055 - 9076

Published: May 29, 2024

Metallaphotoredox catalysis can unlock useful pathways for transforming organic reactants into desirable products, largely due to the conversion of photon energy chemical potential drive redox and bond transformation processes. Despite importance these processes cross-coupling reactions other transformations, their mechanistic details are only superficially understood. In this review, we have provided a detailed summary various photoredox mechanisms that been proposed date Ni-bipyridine (bpy) complexes, focusing separately on photosensitized direct excitation reaction By highlighting multiple key findings, depict how mechanisms, which ultimately define substrate scope, themselves defined by ground- excited-state geometric electronic structures Ni-based intermediates. We further identify knowledge gaps motivate future studies development synergistic research approaches spanning physical, organic, inorganic chemistry communities.

Language: Английский

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Ligand-Enabled “Two-in-One” Metallaphotocatalytic Cross Couplings

ACS Catalysis, Journal Year: 2025, Volume and Issue: 15(3), P. 1635 - 1654

Published: Jan. 15, 2025

Metallaphotoredox cross coupling (MCC) is ranking among the most advanced synthetic methodology as it can access chemical space that difficult to attain under conventional conditions. Earlier developed MCC mandates an independent transition metal catalyst and respective photocatalyst, thus constituting a dual catalytic manifold. Complementarily, paradigm-shifting metallaphotoredox strategy capitalizes on single photoreactive complex emerging, which brings not only operational simplification but also unexpected mechanistic insights. This perspective compiled recent advances in monocatalytic couplings categorized them based ligands confer distinct photoreactivities various mechanisms. To this end, ligand-enabled oxidative addition, transmetalation, reductive elimination other radical-involving pathways were summarized with notable examples. In way, we wish provide handy guideline for readers who are interested emerging field inspire more future endeavors MCCs beyond.

Language: Английский

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Overcoming Photochemical Limitations in Metallaphotoredox Catalysis: Red-Light-Driven C–N Cross-Coupling

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(49), P. 22409 - 22415

Published: Nov. 23, 2022

Aryl amination is an essential transformation for medicinal, process, and materials chemistry. In addition to classic Buchwald–Hartwig conditions, blue-light-driven metallaphotoredox catalysis has emerged as a valuable tool C–N cross-coupling. However, blue light suffers from low penetration through reaction media, limiting its scalability industrial purposes. addition, enhances unwanted side-product formation in catalysis, namely hydrodehalogenation. Low-energy light, such deep red (DR) or near-infrared (NIR), offers solution this problem it can provide enhanced media compared higher-energy wavelengths. Herein, we show that low-energy also enhance the desired reactivity by suppressing We hypothesize reduced side product formed direct photolysis of aryl–nickel bond high-energy leading generation aryl radicals. Using deep-red osmium photocatalyst, demonstrate scope (hetero)aryl bromides amine-based nucleophiles with minimal hydrodehalogenation byproducts.

Language: Английский

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Photochemical Synthesis of Anilines via Ni-Catalyzed Coupling of Aryl Halides with Ammonium Salts

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(24), P. 15590 - 15599

Published: Dec. 5, 2022

Easy, efficient, and economic synthesis of anilines remains an important challenge in synthetic chemistry. In this study, a Ni(OAc)2-bipyridine complex is shown to readily catalyze the amination aryl halides with ammonium salts under direct excitation light, allowing broad array chlorides bromides be converted into corresponding primary (hetero)arylamines absence external photosensitizer. Late-stage modification drug molecules 15N-labeling amines are also demonstrated number examples. Photoinduced generation Ni(I)-bipyridine species believed key step reaction, enabling Ni(I)/Ni(III) cycle for catalytic turnover.

Language: Английский

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Poly(heptazine imide) ligand exchange enables remarkable low catalyst loadings in heterogeneous metallaphotocatalysis

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: March 17, 2023

Abstract The development of heterogeneous metallaphotocatalysis is great interest for sustainable organic synthesis. rational design and controllable preparation well-defined (site-isolated) metal/photo bifunctional solid catalysts to meet such goal remains a critical challenge. Herein, we demonstrate the incorporation privileged homogeneous bipyridyl-based Ni-catalysts into highly ordered crystalline potassium poly(heptazine imide) (K-PHI). A variety PHI-supported cationic (L n Ni-PHI) have been prepared fully characterized by various techniques including NMR, ICP-OES, XPS, HAADF-STEM XAS. L Ni-PHI exhibit exceptional chemical stability recyclability in diverse C−P, C−S, C−O C−N cross-coupling reactions. proximity cooperativity effects significantly enhances photo/Ni dual catalytic activity, thus resulting low catalyst loadings high turnover numbers.

Language: Английский

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Ni‐Catalyzed Photochemical C−N Coupling of Amides with (Hetero)aryl Chlorides

Chemistry - A European Journal, Journal Year: 2023, Volume and Issue: 29(37)

Published: April 17, 2023

This paper reports a photochemical C-N coupling of abundant, but less reactive aryl chlorides, with structurally diverse primary and secondary amides by Ni-mediated without an external photocatalyst. Under the irradiation light (390-395 nm) soluble organic amine as base, reaction allows for successful transformation (hetero)aryl chlorides to wide range N-aryl amides. More than 60 examples are shown, demonstrating feasibility applicability this protocol in synthesis. Mechanic studies indicate that amidation proceeds via Ni(I)-Ni(III) catalytic cycle.

Language: Английский

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Recent advances in C(sp³)–N bond formation via metallaphoto-redox catalysis

Chemical Communications, Journal Year: 2024, Volume and Issue: 60(50), P. 6340 - 6361

Published: Jan. 1, 2024

In this review, the state-of-the-art advances in radical-involved C(sp 3 )–N bond formation via metallaphotoredox catalysis have been highlighted, which are organized according to different catalytic modes, reaction types, and substrate classes.

Language: Английский

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Synthesis, Characterization, and Catalytic Activity of Ni(0) (DQ)dtbbpy, an Air-Stable, Bifunctional Red-Light-Sensitive Precatalyst

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 5, 2025

Despite a well-established and growing body of work on nickel(0) precatalysts, the potential complexes as bifunctional precatalysts remains underexplored. In this study, we synthesized, characterized, evaluated catalytic activity (Ni(0)(DQ)dtbbpy), bifunctional, red-light-sensitive, air-stable complex. Owing to its unique photophysical properties, it effectively catalyzed etherification amination aryl bromides under 620–630 nm light irradiation, functioning both photocatalyst an active metal catalyst. Mechanistic studies density functional theory (DFT) calculations further confirmed exceptional absorption properties Ni(0)(DQ)dtbbpy in red-light region, well electron transfer process triggered by irradiation.

Language: Английский

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