Low-energy photoredox catalysis

Nature Reviews Chemistry, Год журнала: 2024, Номер unknown

Опубликована: Ноя. 11, 2024

Язык: 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, Год журнала: 2025, Номер unknown

Опубликована: Фев. 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.

Язык: Английский

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Red-Light-Active N,C,N-Pincer Bismuthinidene: Excited State Dynamics and Mechanism of Oxidative Addition into Aryl Iodides

Journal of the American Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Фев. 10, 2025

Despite the progress made in field of synthetic organic photocatalysis over past decade, use higher wavelengths, especially those deep-red portion electromagnetic spectrum, remains comparatively rare. We have previously disclosed that a well-defined N,C,N-pincer bismuthinidene (1a) can undergo formal oxidative addition into wide range aryl electrophiles upon absorption low-energy red light. In this study, we map out photophysical dynamics 1a and glean insights nature excited state responsible for activation electrophiles. Transient emission techniques reveal that, irradiation with light, complex undergoes direct S0 → S1 metal-to-ligand charge transfer (MLCT) transition, followed by rapid intersystem crossing (ISC) to highly reducing emissive triplet (−2.61 V vs Fc+/0 MeCN). The low dissipative losses incurred during ISC (∼6% incident light energy) help rationalize ability convert useful chemical energy. Spectroelectrochemical computational data support charge-separated excited-state structure radical-anion character on ligand radical-cation bismuth. Kinetic studies competition experiments afford mechanism iodides; concerted inner-sphere processes from are ruled out, strongly supporting pathway proceeds via outer-sphere dissociative electron transfer.

Язык: Английский

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Red-light-mediated copper-catalyzed photoredox catalysis promotes regioselectivity switch in the difunctionalization of alkenes

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Июнь 18, 2024

Abstract Controlling regioselectivity during difunctionalization of alkenes remains a significant challenge, particularly when the installation both functional groups involves radical processes. In this aspect, methodologies to install trifluoromethane (−CF 3 ) via have been explored, due importance moiety in pharmaceutical sectors; however, these existing reports are limited, most which affording only corresponding β-trifluoromethylated products. The main reason for limitation arises from fact that −CF group served as an initiator those reactions and predominantly preferred be installed at terminal (β) position alkene. On contrary, functionalization internal (α) would provide valuable products, but meticulous approach is necessary win switch. Intrigued by we here develop efficient regioselective strategy where α-position Molecular complexity achieved simultaneous insertion sulfonyl fragment (−SO 2 R) β-position. A precisely regulated sequence generation using red light-mediated photocatalysis facilitates switch position. Furthermore, demonstrates broad substrate scope industrial potential synthesis pharmaceuticals under mild reaction conditions.

Язык: Английский

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Bimetallic Porphyrin Metal–Organic Framework as Photocatalyst for Red-Light-Driven Selective Reduction of Nitroarenes to Aromatic Amines

ACS Sustainable Chemistry & Engineering, Год журнала: 2024, Номер unknown

Опубликована: Ноя. 28, 2024

It is a great challenge to construct green catalytic system for the reduction of nitro compounds corresponding amines under mild conditions. Due low energy red light, it challenging develop photocatalytic selective nitroaromatics aromatic driven by light. A bimetallic porphyrin metal–organic framework (Bi-P(Co)MOF) was characterized Fourier transform infrared spectroscopy, X-ray diffraction, transmission electron microscopy, scanning and energy-dispersive techniques. The constructed photocatalyst Bi-PMOF-Co shows excellent activity conversion in high yields with NaBH4 as reducing agent at room temperature light irradiation. Moreover, protocol showed functional group compatibility, recyclability demonstrated five-cycle tests.

Язык: Английский

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Red-Light Mediated Formylation of Indoles Using Helical Carbenium Ion as Photoredox Catalyst

Chemical Communications, Год журнала: 2025, Номер unknown

Опубликована: Янв. 1, 2025

A red-light ( λ = 640 nm)-mediated C-3 formylation of indoles utilizing a helical carbenium ion as photocatalyst and 2,2-dimethoxy- N , -dimethylethanamine formylating source is presented.

Язык: Английский

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Red-shifted photoredox generation and trapping of alkyl radicals towards bioorthogonality

Organic & Biomolecular Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Янв. 1, 2025

We report two potentially biocompatible photoredox systems for the activation and coupling of redox-active esters using low-energy light BnNAH as reductant.

Язык: Английский

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Triaryl Carbenium Ion Pair Mediated Electrocatalytic Benzylic C−H Oxygenation in Air

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(28)

Опубликована: Апрель 26, 2024

Abstract The selective oxidation of benzylic C−H bonds is a pivotal transformation in organic synthesis. Undoubtedly, achieving efficient and highly aerobic methylarenes to benzaldehydes has been challenging due the propensity benzaldehyde undergo overoxidation under typical conditions. Herein, we propose an innovative approach address this issue by leveraging electrocatalytic processes, facilitated ion‐pair mediators [Ph 3 C] + [B(C 6 F 5 ) 4 ] − . By harnessing power electrochemistry, successfully demonstrated effectiveness our strategy, which enables molecules toluene derivatives. Notably, exhibited high efficiency, excellent selectivity, compatibility with various functional groups, underscoring broad applicability methodology.

Язык: Английский

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Ultrafast Dynamics of a Red-Light-Activated Organic Photocatalyst in the Oxidative Hydroxylation of Phenylboronic Acid

Опубликована: Май 17, 2024

Over the past few years, photoredox catalysis has led to significant transformations in modern synthetic chemistry. It allowed development of new pathways for assembly complex molecular scaffolds using light as a driving force. However, investigations ultrafast light-initiated mechanisms required these reactions are relatively scarce. Here we follow dynamics red-light organic photocatalyst, N,N′-di-n-propyl-1,13-dimethoxyquinacridinium (nPr-DMQA+), aerobic oxidative hydroxylation phenylboronic acid transient absorption and time correlated single photon counting spectroscopy. Global target analysis supports reaction mechanism that proceeds through excited triplet state nPr-DMQA+, leading generation superoxide anion subsequent hydroxylation. The pathway proposed here wide application photocatalytic including those methylene blue other dyes catalysts. Observation nPr-DMQA+ it acts catalyst can provide insights improve efficiency more broadly.

Язык: Английский

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Reductive Electrophotocatalytic α‐C−H Arylation of Cyclic Ketones with Aryl Chlorides

ChemCatChem, Год журнала: 2024, Номер unknown

Опубликована: Май 18, 2024

Abstract α‐Aryl cyclocarbonyls are important building blocks in organic synthesis. While many methods have been developed for their synthesis, the use of readily available and inexpensive aryl chlorides as arylating reagent remains rare. Herein, we report an α‐arylation cyclic ketones with under reductive electrophotocatalytic conditions. 2,6‐Diisopropylphenyl‐containing naphthalenemonoimide was identified optimal electrophotocatalyst, allowing electron‐deficient well electron‐rich mild

Язык: Английский

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