Video Experimental Relacionado

Updated: Aug 20, 2025

Synthesis of Antiviral Tetrahydrocarbazole Derivatives by Photochemical and Acid-catalyzed C-H Functionalization via Intermediate Peroxides CHIPS

Synthesis of Antiviral Tetrahydrocarbazole Derivatives by Photochemical and Acid-catalyzed C-H Functionalization via Intermediate Peroxides CHIPS

Published on: June 20, 2014

Funcionalización radical y iónica de las piridinas, quinolinas e isoquinolinas

Hui Cao¹, Qiang Cheng¹, Armido Studer¹

¹Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Münster, Germany.

Science (New York, N.Y.)

|November 17, 2022

Resumen

Este estudio introduce un nuevo método para la funcionalización meta-CH selectiva de las piridinas. Este proceso libre de catalizadores permite diversas modificaciones químicas, útiles para el desarrollo de fármacos.

Área de la Ciencia:

Química orgánica
Química medicinal
Ciencias de los materiales

Sus antecedentes:

La funcionalización carbono-hidrógeno (C-H) de las piridinas es crucial para sintetizar agroquímicos, productos farmacéuticos y materiales.
Lograr la funcionalización selectiva de meta-C-H en las piridinas es sintéticamente desafiante debido a sus propiedades electrónicas.

Objetivo del estudio:

Desarrollar un protocolo altamente regioselectivo para la funcionalización meta-CH de las piridinas.
Establecer una plataforma versátil para la funcionalización en etapa tardía de compuestos que contienen piridina.

Principales métodos:

Se empleó un proceso de dearomatización-rearomatización neutro-redóxido.
El método facilita varias transformaciones, incluida la trifluorometilación, la perfluoroalquilación, la halogenación, la nitratación, la sulfanilación y la selenilación.

Principales resultados:

El protocolo logra una alta regioselectividad para la funcionalización meta-CH de las piridinas.
Las reacciones proceden a través de vías radicales e iónicas, lo que demuestra un amplio alcance y aplicabilidad.
La naturaleza libre de catalizadores de las reacciones mejora su utilidad práctica.

Conclusiones:

Esta nueva estrategia de activación dearomativa proporciona una poderosa plataforma de diversificación para la funcionalización meta-selectiva de la piridina.
Los métodos desarrollados son adecuados para la funcionalización de las moléculas de fármacos en etapa tardía, acelerando el descubrimiento y desarrollo de fármacos.

Más Videos Relacionados

Facile Preparation of 4-Substituted Quinazoline Derivatives

Facile Preparation of 4-Substituted Quinazoline Derivatives

Published on: February 15, 2016

Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts

Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts

Published on: February 24, 2015

Videos de Conceptos Relacionados

ortho–para-Directing Activators: –CH3, –OH, –&NoBreak;NH2, –OCH3

ortho–para-Directing Activators: –CH₃, –OH, –⁠NH₂, –OCH₃

All ortho–para directors, excluding halogens, are activating groups. These groups donate electrons to the ring, making the ring carbons electron-rich. Consequently, the reactivity of the aromatic ring towards electrophilic substitution increases. For instance, the nitration of anisole is about 10,000 times faster than the nitration of benzene. The electron-donating effect of the methoxy group in anisole activates the ortho and para positions on the ring and stabilizes the corresponding...

Radicals: Electronic Structure and Geometry

Radicals: Electronic Structure and Geometry

This lesson delves into the geometry of a radical, which is influenced by the electronic structure of the molecule. The principle is similar to that of a lone pair, where the unpaired electron influences the geometry at the radical center.
Accordingly, the structure of a trivalent radical lies between the geometries of carbocations and carbanions. An sp2-hybridized carbocation is trigonal planar, while an sp3-hybridized carbanion is trigonal pyramidal. Here, the difference in geometry is...

Radical Reactivity: Overview

Radical Reactivity: Overview

Radicals, the highly reactive species, gain stability by undergoing three different reactions. The first reaction involves a radical-radical coupling, in which a radical combines with another radical, forming a spin‐paired molecule. The second reaction is between a radical and a spin‐paired molecule, generating a new radical and a new spin‐paired molecule. The third reaction is radical decomposition in a unimolecular reaction, forming a new radical and a spin‐paired...

Radical Formation: Overview

Radical Formation: Overview

A bond can be broken either by heterolytic bond cleavage to form ions or homolytic bond cleavage to yield radicals. A fishhook arrow is used to represent the motion of a single electron in homolytic bond cleavage. There are two main sources from which radicals can be formed:
Radicals from spin-paired molecules:
Radicals can be obtained from spin-paired molecules either by homolysis or electron transfer. While two radicals are formed in the former, an electron is added in the...

Radical Formation: Homolysis

Radical Formation: Homolysis

A bond is formed between two atoms by sharing two electrons. When this bond is broken by supplying sufficient energy, either two electrons can be taken up by one atom forming ions by the cleavage called heterolysis, or the two electrons are shared by two atoms, with one each creating radicals by the cleavage called homolysis.

Radical Formation: Addition

Radical Formation: Addition

Radicals can be formed by adding a radical to a spin-paired molecule. This is typically observed with unsaturated species, where the addition of a radical across the π bond leads to the production of a new radical by dissolving the π bond. For example, the addition of a Br radical to an alkene yields a carbon-centered radical.
Similar to charge conservation in chemical reactions, spin conservation is implicit for radical reactions. Accordingly, the product formed must possess an...