Discovery and Elucidation of Counteranion Dependence in Photoredox Catalysis DOI
Elliot P. Farney, Steven J. Chapman, Wesley B. Swords

и другие.

Journal of the American Chemical Society, Год журнала: 2019, Номер 141(15), С. 6385 - 6391

Опубликована: Март 21, 2019

Over the past decade, there has been a renewed interest in use of transition metal polypyridyl complexes as photoredox catalysts for variety innovative synthetic applications. Many derivatives these are known, and effect ligand modifications on their efficacy subject extensive, systematic investigation. However, influence photocatalyst counteranion received little attention, despite fact that generally cationic nature. Herein, we demonstrate effects exert surprising, dramatic impact rate representative photocatalytic radical cation Diels–Alder reaction. A detailed analysis reveals identity impacts multiple aspects reaction mechanism. Most notably, photocatalysts with more noncoordinating counteranions yield powerful triplet excited state oxidant longer chain length. It is proposed this arises from Coulombic ion-pairing interactions between both catalyst intermediate, respectively. The comparatively slower coordinating can be rescued by using hydrogen-bonding anion binders attenuate deleterious interactions. These results importance variable design optimization transformations suggest novel strategy organic reactions class photocatalysts.

Язык: Английский

Photoenzymatic enantioselective intermolecular radical hydroamination DOI
Zhengyi Zhang, Jianqiang Feng, Chao Yang

и другие.

Nature Catalysis, Год журнала: 2023, Номер 6(8), С. 687 - 694

Опубликована: Июль 31, 2023

Язык: Английский

Процитировано

55
Organocatalytic Enantioselective Addition of α-Aminoalkyl Radicals to Isoquinolines DOI
Xiangyuan Liu, Yang Liu,

Guobi Chai

и другие.

Organic Letters, Год журнала: 2018, Номер 20(19), С. 6298 - 6301

Опубликована: Сен. 26, 2018

With a dual organocatalytic system involving chiral phosphoric acid and dicyanopyrazine-derived chromophore (DPZ) photosensitizer under the irradiation with visible light, an enantioselective Minisci-type addition of α-amino acid-derived redox-active esters (RAEs) to isoquinolines has been developed. A variety prochiral α-aminoalkyl radicals generated from RAEs were successfully introduced on isoquinolines, providing range valuable α-isoquinoline-substituted secondary amines in high yields good excellent enantioselectivities.

Язык: Английский

Процитировано

134
Photocatalytic Generation of Aminium Radical Cations for C–N Bond Formation DOI
Jacob M. Ganley, Philip R. D. Murray, Robert R. Knowles

и другие.

ACS Catalysis, Год журнала: 2020, Номер 10(20), С. 11712 - 11738

Опубликована: Сен. 11, 2020

Aminium radical cations have been extensively studied as electrophilic aminating species that readily participate in C–N bond forming processes with alkenes and arenes. However, their utility synthesis has limited, generation required unstable, reactive starting materials harsh reaction conditions. Visible-light photoredox catalysis emerged a platform for the mild production of aminium from either unfunctionalized or N-functionalized amines. This Perspective covers recent synthetic methods rely on photocatalytic formation, specifically context alkene hydroamination, arene C–H amination, mesolytic cleavage alkoxyamines.

Язык: Английский

Процитировано

134
Mechanistische Studien in der Photokatalyse DOI Open Access
Luca Buzzetti, Giacomo E. M. Crisenza, Paolo Melchiorre

и другие.

Angewandte Chemie, Год журнала: 2018, Номер 131(12), С. 3768 - 3786

Опубликована: Окт. 19, 2018

Abstract Die sich rasant entwickelnden Felder der Photo‐ und Photoredoxkatalyse bieten neue Gelegenheiten, das Potential synthetisch‐organischen Chemie zu erweitern. Fortschritte bei photokatalytischen Prozessen haben bisher vor allem aus empirischen Entdeckungen Suche nach neuen Reaktionen ergeben. allgemeine Wahrnehmung jedoch ist, dass die Photokatalyse in eine reifere Phase eintritt, Kombination experimenteller mechanistischer Studien Vorreiterrolle für weitere Innovationen spielt. Dieser Aufsatz beschreibt mechanistischen Schlüsselstudien, Entwicklung photochemischer Prozesse Betracht gezogen werden sollten, sowie geeignetsten verfügbaren Techniken zur Gewinnung relevanter Informationen. Diskussion verweist auf ausgewählte Fallstudien, um zeigen, wie mechanistische Untersuchungen instrumentelle Rolle Entdeckung synthetisch nützlicher, photokatalytischer Transformationen spielen können.

Процитировано

120
Discovery and Elucidation of Counteranion Dependence in Photoredox Catalysis DOI
Elliot P. Farney, Steven J. Chapman, Wesley B. Swords

и другие.

Journal of the American Chemical Society, Год журнала: 2019, Номер 141(15), С. 6385 - 6391

Опубликована: Март 21, 2019

Over the past decade, there has been a renewed interest in use of transition metal polypyridyl complexes as photoredox catalysts for variety innovative synthetic applications. Many derivatives these are known, and effect ligand modifications on their efficacy subject extensive, systematic investigation. However, influence photocatalyst counteranion received little attention, despite fact that generally cationic nature. Herein, we demonstrate effects exert surprising, dramatic impact rate representative photocatalytic radical cation Diels–Alder reaction. A detailed analysis reveals identity impacts multiple aspects reaction mechanism. Most notably, photocatalysts with more noncoordinating counteranions yield powerful triplet excited state oxidant longer chain length. It is proposed this arises from Coulombic ion-pairing interactions between both catalyst intermediate, respectively. The comparatively slower coordinating can be rescued by using hydrogen-bonding anion binders attenuate deleterious interactions. These results importance variable design optimization transformations suggest novel strategy organic reactions class photocatalysts.

Язык: Английский

Процитировано

118