Scalable Photoelectrochemical Dehydrogenative Cross‐Coupling of Heteroarenes with Aliphatic C−H Bonds

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 59(34), P. 14275 - 14280

Published: June 3, 2020

Heteroarenes are structural motifs found in many bioactive compounds and functional materials. Dehydrogenative cross-coupling of heteroarenes with aliphatic C-H bonds provides straightforward access to functionalized from readily available Established methods employ stoichiometric chemical oxidants under conditions heating or light irradiation. By merging electrochemistry photochemistry, we have achieved efficient photoelectrochemical dehydrogenative C(sp3 )-H donors through H2 evolution, without the addition metal catalysts oxidants. Mechanistically, donor is converted a nucleophilic carbon radical H-atom transfer chlorine atom, which produced by irradiation anodically generated Cl2 Cl- . The then undergoes substitution heteroarene afford alkylated products.

Language: Английский

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Photoelectrochemical C−H Alkylation of Heteroarenes with Organotrifluoroborates

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 58(14), P. 4592 - 4595

Published: Jan. 16, 2019

A photoelectrochemical method for the C-H alkylation of heteroarenes with organotrifluoroborates has been developed. The merger electrocatalysis and photoredox catalysis provides a chemical oxidant-free approach generation functionalization alkyl radicals from organotrifluoroborates. variety were functionalized using primary, secondary, tertiary alkyltrifluoroborates excellent regio- chemoselectivity.

Language: Английский

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Enantioselective Pallada‐Electrocatalyzed C−H Activation by Transient Directing Groups: Expedient Access to Helicenes

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 59(32), P. 13451 - 13457

Published: April 3, 2020

Abstract Asymmetric pallada‐electrocatalyzed C−H olefinations were achieved through the synergistic cooperation with transient directing groups. The electrochemical, atroposelective activations realized high position‐, diastereo‐, and enantio‐control under mild reaction conditions to obtain highly enantiomerically‐enriched biaryls fluorinated N−C axially chiral scaffolds. Our strategy provided expedient access to, among others, novel BINOLs, dicarboxylic acids helicenes of value asymmetric catalysis. Mechanistic studies by experiments computation key insights into catalyst's mode action.

Language: Английский

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En Route to Intermolecular Cross-Dehydrogenative Coupling Reactions

The Journal of Organic Chemistry, Journal Year: 2019, Volume and Issue: 84(20), P. 12705 - 12721

Published: Aug. 23, 2019

Cross-coupling reaction between two C-H bonds has become a fundamental strategy in synthetic organic chemistry. With its increasing importance green chemistry, atom economy, and step development sky-rocketed within the last 20 years, with term "cross-dehydrogenative coupling (CDC)" popularized progressed by group of Li others to describe direct Y-Z bond formations from Y-H Z-H under oxidative conditions. Among all types CDC reactions, C-C are prime building up molecular complexity but their categorization currently remains disarray due wide diversity, resulting frequent display separate topics. In this Perspective, contemporary via activation strategies is presented herein, which could be vital for future designs. mechanism-based discussion, we wish that minireview will help more chemists gain insight into design reactions inspires ideas on topic.

Language: Английский

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Electrophotocatalytic Decarboxylative C−H Functionalization of Heteroarenes

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 59(26), P. 10626 - 10632

Published: March 30, 2020

Abstract Decarboxylative C−H functionalization reactions are highly attractive methods for forging carbon–carbon bonds considering their inherent step‐ and atom‐economical features the pervasiveness of carboxylic acids bonds. An ideal approach to achieve these dehydrogenative transformations is through hydrogen evolution without using any chemical oxidants. However, effective couplings by decarboxylative bond formation with proton reduction remain an unsolved challenge. Herein, we report electrophotocatalytic that merges organic electrochemistry photocatalysis efficient direct alkylation carbamoylation heteroaromatic compounds evolution. This method, which combines high efficiency selectivity in promoting decarboxylation superiority effecting reduction, enables coupling a wide range bases variety oxamic acids. Advantageously, this method scalable decagram amounts, applicable late‐stage drug molecules.

Language: Английский

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