Visible-Light-Driven Catalytic Reductive Carboxylation with CO₂

ACS Catalysis, Год журнала: 2020, Номер 10(19), С. 10871 - 10885

Опубликована: Авг. 28, 2020

Carbon dioxide (CO2) is an important C1 source for the generation of carboxylic acids and derivatives. Stoichiometric catalytic carboxylation nucleophiles, including organometallic reagents, with CO2 has been widely investigated. Since many kinds reagents are prepared from electrophiles, transition-metal-catalyzed direct diverse electrophiles attracted much attention high step economy user-friendly protocols. Although significant progress achieved, use stoichiometric metallic or pyrophoric reductants common. The renaissance photochemistry seen numerous efforts devoted to light-driven CO2, which become one most active directions in this field. In Perspective, we summarize recent advances visible-light-driven reductive substrates, such as unsaturated hydrocarbons, organic (pseudo)halides, imines, presence mild electron donors, amines, Hantzsch esters, formates. We highlight mechanisms reactions, can proceed absence a photoredox catalyst dual visible light photoredox/transition metal system. also discuss future field offer some insight into challenges that remain.

Язык: Английский

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Visible Light-Induced Excited-State Transition-Metal Catalysis

Trends in Chemistry, Год журнала: 2019, Номер 1(5), С. 510 - 523

Опубликована: Июнь 1, 2019

Язык: Английский

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Three-Component, Interrupted Radical Heck/Allylic Substitution Cascade Involving Unactivated Alkyl Bromides

Journal of the American Chemical Society, Год журнала: 2020, Номер 142(22), С. 10173 - 10183

Опубликована: Май 7, 2020

Developing efficient and selective strategies to approach complex architectures containing (multi)stereogenic centers has been a long-standing synthetic challenge in both academia industry. Catalytic cascade reactions represent powerful means of rapidly leveraging molecular complexity from simple feedstocks. Unfortunately, carrying out Heck-type involving unactivated (tertiary) alkyl halides remains an unmet owing unavoidable β-hydride elimination. Herein, we show that modular, practical, general palladium-catalyzed, radical three-component coupling can indeed overcome the aforementioned limitations through interrupted Heck/allylic substitution sequence mediated by visible light. Selective 1,4-difunctionalization 1,3-dienes, such as butadiene, achieved employing different commercially available nitrogen-, oxygen-, sulfur-, or carbon-based nucleophiles bromides (>130 examples, mostly >95:5 E/Z, >20:1 rr). Sequential C(sp3)–C(sp3) C–X (N, O, S) bonds have constructed efficiently with broad scope high functional group tolerance. The flexibility versatility strategy illustrated gram-scale reaction streamlined syntheses ether, sulfone, tertiary amine products, some which would be difficult access via currently established methods.

Язык: Английский

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Photocarboxylation with CO₂: an appealing and sustainable strategy for CO₂ fixation

Green Chemistry, Год журнала: 2020, Номер 22(21), С. 7301 - 7320

Опубликована: Янв. 1, 2020

This review discusses recent advances in the photocatalytic carboxylation of C(sp³)–X (X = H, N) bonds, C(sp²)–X N, (pseudo)halide) bonds and C(sp)–H with CO₂.

Язык: Английский

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Excited-State Palladium-Catalyzed Radical Migratory Mizoroki–Heck Reaction Enables C2-Alkenylation of Carbohydrates

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(8), С. 3353 - 3359

Опубликована: Фев. 21, 2022

Excited-state palladium catalysis has emerged as a promising strategy for developing novel and valuable reactions. Herein, we report the first excited-state Pd-catalyzed 1,2-radical migratory Mizoroki–Heck reaction that enables C2-alkenylation of carbohydrates using readily available 1-bromosugars alkenes. The tolerates wide variety functional groups complex molecular architectures, including derivatives natural products marketed drugs. Preliminary mechanistic studies DFT calculations suggest involvement visible-light-induced photoexcitation Pd species, 1,2-spin-centered-shift (SCS) process, Heck-type cross-coupling reaction. expands reactivity profile provides streamlined protocol preparation C2-alkenylated carbohydrate mimetics to aid discovery development new therapeutics, agrochemicals, materials.

Язык: Английский

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Recent Advances in Visible Light Induced Palladium Catalysis

Angewandte Chemie International Edition, Год журнала: 2023, Номер 63(9)

Опубликована: Ноя. 14, 2023

Visible light-induced Pd catalysis has emerged as a promising subfield of photocatalysis. The hybrid nature radical species enabled wide array radical-based transformations otherwise challenging or unknown via conventional chemistry. In parallel to the ongoing pursuit alternative, readily available precursors, notable discoveries have demonstrated that photoexcitation can alter not only oxidative addition but also other elementary steps. This Minireview highlights recent progress in this area.

Язык: Английский

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Selective and Catalytic Hydrocarboxylation of Enamides and Imines with CO₂ to Generate α,α‐Disubstituted α‐Amino Acids

Angewandte Chemie International Edition, Год журнала: 2018, Номер 57(42), С. 13897 - 13901

Опубликована: Авг. 30, 2018

Abstract The first catalytic hydrocarboxylation of enamides and imines with CO 2 to generate valuable α,α‐disubstituted α‐amino acids is reported. Notably, excellent chemo‐ regio‐selectivity are achieved, significantly different from previous reports on β‐carboxylation enamides, homocoupling or reduction imines. Moreover, this transition‐metal‐free procedure exhibits low loading an inexpensive catalyst, easily available substrates, mild reaction conditions, high efficiency, facile scalability easy product derivatization, providing great potential for application in organic synthesis, pharmaceutical chemistry, biochemistry.

Язык: Английский

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Palladium-catalyzed reductive electrocarboxylation of allyl esters with carbon dioxide

Organic Chemistry Frontiers, Год журнала: 2018, Номер 5(14), С. 2244 - 2248

Опубликована: Янв. 1, 2018

Palladium-catalyzed regioselective electrocarboxylation of homostyrenyl acetates with CO₂ has been successfully developed, providing α-aryl carboxylic acids good selectivity and yield.

Язык: Английский

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Visible‐Light Photoredox‐Catalyzed Remote Difunctionalizing Carboxylation of Unactivated Alkenes with CO₂

Angewandte Chemie International Edition, Год журнала: 2020, Номер 59(47), С. 21121 - 21128

Опубликована: Авг. 4, 2020

Remote difunctionalization of unactivated alkenes is challenging but a highly attractive tactic to install two functional groups across long distances. Reported herein the first remote with CO2 . This visible-light photoredox catalysis strategy provides facile method synthesize series carboxylic acids bearing valuable fluorine- or phosphorus-containing groups. Moreover, this versatile protocol shows mild reaction conditions, broad substrate scope, and good functional-group tolerance. Based on DFT calculations, radical adds an alkene smoothly form new carbon radical, followed by 1,5-hydrogen atom-transfer process, rate-limiting step, generating more stable benzylic radical. The reduction radicals IrII species generates corresponding carbanions as key intermediates, which further undergo nucleophilic attack generate carboxylates.

Язык: Английский

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Palladium-Catalyzed Dual Ligand-Enabled Alkylation of Silyl Enol Ether and Enamide under Irradiation: Scope, Mechanism, and Theoretical Elucidation of Hybrid Alkyl Pd(I)-Radical Species

ACS Catalysis, Год журнала: 2019, Номер 10(2), С. 1334 - 1343

Опубликована: Дек. 19, 2019

We report herein that a palladium catalyst in combination with dual phosphine ligand system catalyzes alkylation of silyl enol ether and enamide broad scope tertiary, secondary, primary alkyl bromides under mild irradiation conditions by blue light-emitting diodes. The reactions effectively deliver α-alkylated ketones N-acyl ketimines, it is difficult to prepare the latter other methods stereoselective manner. ketimine products can be further subjected chiral phosphoric acid-catalyzed asymmetric reduction Hantzsch ester N-acyl-protected α-arylated aliphatic amines high enantioselectivity up 99% ee, thus providing method for facile synthesis amines, which are importance medicinal chemistry research. N-acetyl product also reacted smoothly various types Grignard reagents afford sterically bulky α-tertiary yields. Theoretical studies experimental investigation provide understanding reaction mechanism respect effect catalytic cycle. suggested proceed via hybrid Pd(I)-radical species generated inner-sphere electron transfer phosphine-coordinated Pd(0) bromide. This intriguing elucidated theoretical calculation triplet coordinated three atoms distorted tetrahedral geometry, spin prohibition rather than metal-to-ligand charge contributes kinetic stability impede recombination generate Pd(II) intermediate.

Язык: Английский

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