Photochemical and Electrochemical Applications of Proton-Coupled Electron Transfer in Organic Synthesis

Chemical Reviews, Год журнала: 2021, Номер 122(2), С. 2017 - 2291

Опубликована: Ноя. 23, 2021

We present here a review of the photochemical and electrochemical applications multi-site proton-coupled electron transfer (MS-PCET) in organic synthesis. MS-PCETs are redox mechanisms which both an proton exchanged together, often concerted elementary step. As such, MS-PCET can function as non-classical mechanism for homolytic bond activation, providing opportunities to generate synthetically useful free radical intermediates directly from wide variety common functional groups. introduction practitioner’s guide reaction design, with emphasis on unique energetic selectivity features that characteristic this class. then chapters oxidative N–H, O–H, S–H, C–H homolysis methods, generation corresponding neutral species. Then, reductive PCET activations involving carbonyl, imine, other X═Y π-systems, heteroarenes, where ketyl, α-amino, heteroarene-derived radicals be generated. Finally, we asymmetric catalysis materials device applications. Within each chapter, subdivide by group undergoing homolysis, thereafter type transformation being promoted. Methods published prior end December 2020 presented.

Язык: Английский

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HFIP in Organic Synthesis

Chemical Reviews, Год журнала: 2022, Номер 122(15), С. 12544 - 12747

Опубликована: Июль 17, 2022

1,1,1,3,3,3-Hexafluoroisopropanol (HFIP) is a polar, strongly hydrogen bond-donating solvent that has found numerous uses in organic synthesis due to its ability stabilize ionic species, transfer protons, and engage range of other intermolecular interactions. The use this exponentially increased the past decade become choice some areas, such as C–H functionalization chemistry. In review, following brief history HFIP an overview physical properties, literature examples reactions using or additive are presented, emphasizing effect each reaction.

Язык: Английский

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Recent developments on 1,2-difunctionalization and hydrofunctionalization of unactivated alkenes and alkynes involving C–S bond formation

Organic Chemistry Frontiers, Год журнала: 2023, Номер 10(5), С. 1322 - 1345

Опубликована: Янв. 1, 2023

Functionalization of alkenes/alkynes is a highly effective route to achieve molecular complexity. This review summarizes recent progresses on the 1,2-difunctionalization/hydrofunctionalization unactivated with C−S bond formation.

Язык: Английский

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Enantioselective Synthesis of Planar‐Chiral Sulfur‐Containing Cyclophanes by Chiral Sulfide Catalyzed Electrophilic Sulfenylation of Arenes

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(10)

Опубликована: Янв. 17, 2024

Abstract An efficient catalytic asymmetric electrophilic sulfenylation reaction for the synthesis of planar‐chiral sulfur‐containing cyclophanes has been developed first time. This was achieved by using a new Lewis base catalyst and ortho ‐trifluoromethyl‐substituted sulfenylating reagent. Using substrates with low rotational energy barrier, transformation proceeded through dynamic kinetic resolution, high barrier allowed to undergo resolution process. Meanwhile, this compatible desymmetrization process when symmetric were used. Various readily obtained in moderate excellent yields enantioselectivities (up 97 % yield 95 ee). approach used synthesize pharmaceutically relevant molecules. Density functional theory calculations showed that π‐π interactions between sulfenyl group aromatic ring substrate play crucial role enantioinduction reaction.

Язык: Английский

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Enantioselective Construction of Axially Chiral Amino Sulfide Vinyl Arenes by Chiral Sulfide‐Catalyzed Electrophilic Carbothiolation of Alkynes

Angewandte Chemie International Edition, Год журнала: 2020, Номер 59(12), С. 4959 - 4964

Опубликована: Янв. 22, 2020

The enantioselective construction of axially chiral compounds by electrophilic carbothiolation alkynes is disclosed for the first time. This transformation enabled use a Ts-protected bifunctional sulfide catalyst and Ms-protected ortho-alkynylaryl amines (Ts=tosyl; Ms=mesyl). Both arylthiolating trifluoromethylthiolating reagents are suitable this reaction. obtained products vinyl-aryl amino sulfides can be easily converted into biaryl sulfides, sulfoxides, amines, other valuable difunctionalized compounds.

Язык: Английский

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Catalytic, Enantioselective Sulfenofunctionalization of Alkenes: Development and Recent Advances

Angewandte Chemie International Edition, Год журнала: 2020, Номер 59(45), С. 19796 - 19819

Опубликована: Май 26, 2020

The last decade has witnessed a burgeoning of new methods for the enantioselective vicinal difunctionalization alkenes initiated by electrophilic sulfenyl group transfer. addition sulfenium ions to results in generation chiral, non-racemic thiiranium ions. These highly reactive intermediates are susceptible attack myriad nucleophiles stereospecific ring-opening event afford anti 1,2-sulfenofunctionalized products. practical application ion transfer been enabled advances field Lewis base catalysis. This Review will chronicle initial discovery and characterization followed determination their configurational stability challenges developing variants. Once framework reactivity established, critical analysis pioneering studies be presented. Finally, comprehensive discussion modern synthetic applications categorized around type nucleophile employed sulfenofunctionalization.

Язык: Английский

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Selective Difunctionalization of Unactivated Aliphatic Alkenes Enabled by a Metal–Metallaaromatic Catalytic System

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(5), С. 2301 - 2310

Опубликована: Янв. 25, 2022

The design of organometallic catalysts is crucial in the development catalytic reactions. Herein, we describe a heterometallic [Os-Cu] complex with characteristics bimetallics, metallaaromatics, and pincer complexes. This serves as highly effective catalyst for selective amino- oxyselenation unactivated alkenes. More than 80 examples including challenging substrates unsymmetric aliphatic alkenes amine-based nucleophiles such reactions are provided. These produce 1,2-difunctionalized products good yields high levels chemo-, regio-, stereoselectivity. Our studies revealed following: (i) usually inert osmium center activates N- or O-centered nucleophiles. (ii) copper–osmium bonding its cooperative effects play essential roles control selectivity by bringing reaction components into close proximity. (iii) metallaaromatic moiety helps to stabilize intermediate. findings provide versatile platform based on metal–metallaaromatic that have not been attained previously bimetallic

Язык: Английский

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Chiral Selenide/Achiral Sulfonic Acid Cocatalyzed Atroposelective Sulfenylation of Biaryl Phenols via a Desymmetrization/Kinetic Resolution Sequence

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(7), С. 2943 - 2952

Опубликована: Фев. 10, 2022

Enantioselective synthesis of axially chiral sulfur-containing biaryl derivatives through the electrophilic sulfenylation phenols has been achieved for first time. This catalytic asymmetric system, which involves sequential desymmetrization and kinetic resolution, is enabled by a combination novel 3,3'-disubstituted BINOL-derived selenide catalyst an achiral sulfonic acid. Control experiments computational studies suggest that multiple noncovalent interactions between cocatalysts substrate, especially network hydrogen bond interactions, play crucial role in determining enantioselectivity reactivity.

Язык: Английский

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Chalcogen bonding catalysis

Chemical Society Reviews, Год журнала: 2023, Номер 53(2), С. 586 - 605

Опубликована: Дек. 7, 2023

Catalysts play a major role in chemical synthesis, and catalysis is considered to be green economic process. Catalysis dominated by covalent interactions between the catalyst substrate. The design of non-covalent catalysts came into limelight only recently. Hydrogen bonding (HB) are well established among catalysts, including asymmetric HB catalysts. Though halogen (XB) its version gaining admiration, chalcogen (ChB) budding stage. This tutorial review will focus on recently evolved emphasis given chiral molecules. Since successful enantioselective yet reported, this basics catalysis, chalcogenide rigidification transition states ChB, stabilization cations chalcogens, details unsuccessful enantioseparation racemic molecules using existence ChB biomolecules.

Язык: Английский

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Difunctionalization Processes Enabled by Hexafluoroisopropanol

ACS Organic & Inorganic Au, Год журнала: 2024, Номер 4(3), С. 287 - 300

Опубликована: Март 4, 2024

In the past 5 years, hexafluoroisopropanol (HFIP) has been used as a unique solvent or additive to enable challenging transformations through substrate activation and stabilization of reactive intermediates. this Review, we aim at describing difunctionalization processes which were unlocked when HFIP was involved. Specifically, focus on cyclizations additions alkenes, alkynes, epoxides, carbonyls that introduce wide range functional groups interest.

Язык: Английский

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