Light‐Mediated Radical Addition to Azomethine Compounds: Novel Reactivity and Activation Modes DOI Open Access

Zakhar M. Rubanov,

Vitalij V. Levin, Alexander D. Dilman

et al.

The Chemical Record, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 17, 2024

Abstract Azomethines is a class of compounds, which have traditionally served as electrophilic substrates, but their reactions with radicals long been limited. Photocatalysis provided ample opportunities for promoting these reactions, wide variety reagents serving precursors radicals. Besides regular addition mode at the azomethine fragment, oxidative pathway, in C=N bond remains product, has become possible by proper selection redox catalyst. This review summarizes new developments this rapidly developing field over past five years. New concepts on activation towards radical attack are discussed.

Language: Английский

Unveiling Heavier Dihydropyridine Chalcogenol Esters in Metallaphotoredox Catalyst-Enabled Regioselective Hydrothio(seleno)carbonylation DOI
Amit Pal, Sandip Bag,

Sariga Mangalamundackal Vijayan

et al.

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 23, 2025

Herein, aromaticity-driven thio(seleno)ester group transfer from novel 1,4-dihydropyridine thio(seleno)esters to alkene feedstocks is disclosed by merging palladium and photoredox catalysis. In this process, photoactivation of dihydropyridine integrated with regioselective hydrometalation alkenes, avoiding photoinduced Pd-C bond homolysis organopalladium intermediates. Additionally, a hydroselenocarbonylation an accomplished for the first time using bench-stable selenoester reagent. The activation mode thioesters has been illustrated detailed mechanistic studies, spectroscopic analysis, intermediate trapping, isotope labeling experiments.

Language: Английский

Citations

0
Photocatalytic Pyridyl-carbamoylation of Alkenes for Accessing β-Pyridyl Amides DOI
Jian Cui, Zhikai Li, Yun Mao

et al.

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: March 7, 2025

The β-pyridyl amide is a critical scaffold in medical discovery yet lacks efficient synthetic methods. Here, we describe, for the first time, visible-light-induced, redox-neutral radical cross-coupling reaction involving alkenes, oxamic acids, and cyanopyridines that offers versatile assembly of β-pyridylamides. This approach features mild conditions, high step efficiency, substrate breadth, providing green strategy alkene pyridyl-carbamoylation. Achieving this transformation relies on catalytic system, which adeptly avoids competing nucleophilic carbamoyl with electrophilic pyridyl radical, enabling three-component tandem process chemoselectivity.

Language: Английский

Citations

0
Light‐Mediated Radical Addition to Azomethine Compounds: Novel Reactivity and Activation Modes DOI Open Access

Zakhar M. Rubanov,

Vitalij V. Levin, Alexander D. Dilman

et al.

The Chemical Record, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 17, 2024

Abstract Azomethines is a class of compounds, which have traditionally served as electrophilic substrates, but their reactions with radicals long been limited. Photocatalysis provided ample opportunities for promoting these reactions, wide variety reagents serving precursors radicals. Besides regular addition mode at the azomethine fragment, oxidative pathway, in C=N bond remains product, has become possible by proper selection redox catalyst. This review summarizes new developments this rapidly developing field over past five years. New concepts on activation towards radical attack are discussed.

Language: Английский

Citations

2