Video Experimental Relacionado

Updated: Jun 16, 2025

[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst

[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst

Published on: May 21, 2019

Los radicales de boro persistentes como catalizadores fotorreductivos para borilaciones debrominativas

Jingjing Wu¹, Hui Wang¹, Huaquan Fang¹

¹School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, U.K.

Journal of the American Chemical Society

|May 30, 2025

Resumen

Los radicales orgánicos persistentes, una vez considerados altamente reactivos, pueden ser estables. Los nuevos radicales de borilo-bipiridina actúan como potentes catalizadores fotorredóxicos, permitiendo nuevas transformaciones químicas.

Área de la Ciencia:

Química orgánica
La fotoquímica
Catálisis

Sus antecedentes:

Los radicales libres orgánicos suelen ser muy reactivos con vidas cortas.
Los radicales persistentes, aunque estables en los estados básicos, pueden formar estados excitados reactivos tras la fotoexcitación.
Las aplicaciones de los radicales persistentes en las reacciones fotoquímicas son limitadas.

Objetivo del estudio:

Identificar nuevos radicales persistentes con potencial como reactivos o catalizadores fotoquímicos.
Para explorar la actividad catalítica fotorredóxica de una nueva clase de radicales persistentes.

Principales métodos:

Generación de radicales de borilo-bipiridina mediante mezcla de reactivos de bipiridina y diboron.
Caracterización de las propiedades de los radicales, incluidos los potenciales de reducción del estado excitado.
Demostración de la actividad catalítica en la promoción de las reacciones de borilación.

Principales resultados:

Identificación de los radicales de borilo-bipiridina persistentes
Estos radicales exhiben estados excitados altamente reductores, comparables a los potentes fotorreducentes.
Los radicales funcionan como catalizadores fotorredóxicos en estado doble.

Conclusiones:

Los radicales de borilo-bipiridina persistentes representan una nueva clase de catalizadores fotorredóxicos potentes.
Sus fuertes potenciales de reducción de estado excitado abren vías para nuevas transformaciones fotoquímicas.
Este descubrimiento amplía la utilidad de los radicales persistentes en la química sintética.

Más Videos Relacionados

Synthesis of a Borylated Ibuprofen Derivative Through Suzuki Cross-Coupling and Alkene Boracarboxylation Reactions

Synthesis of a Borylated Ibuprofen Derivative Through Suzuki Cross-Coupling and Alkene Boracarboxylation Reactions

Published on: November 30, 2022

Atom Transfer Radical Polymerization of Functionalized Vinyl Monomers Using Perylene as a Visible Light Photocatalyst

Atom Transfer Radical Polymerization of Functionalized Vinyl Monomers Using Perylene as a Visible Light Photocatalyst

Published on: April 22, 2016

Videos de Conceptos Relacionados

Hydroboration-Oxidation of Alkenes

Hydroboration-Oxidation of Alkenes

In addition to the oxymercuration–demercuration method, which converts the alkenes to alcohols with Markovnikov orientation, a complementary hydroboration-oxidation method yields the anti-Markovnikov product. The hydroboration reaction, discovered in 1959 by H.C. Brown, involves the addition of a B–H bond of borane to an alkene giving an organoborane intermediate. The oxidation of this intermediate with basic hydrogen peroxide forms an alcohol.

Radical Reactivity: Steric Effects

Radical Reactivity: Steric Effects

The presence of electron-donating, electron-withdrawing, or conjugating groups adjacent to a radical center, imparts electronic stabilization to the radicals. Examples of such electronically-stabilized radicals are triphenylmethyl, tetramethylpiperidine‐N‐oxide, and 2,2‐diphenyl‐1‐picrylhydrazyl. These radicals are remarkably stable and are known as persistent radicals. Some of the persistent radicals can even be isolated and purified.
Along with electronic...

Alkynes to Aldehydes and Ketones: Hydroboration-Oxidation

Alkynes to Aldehydes and Ketones: Hydroboration-Oxidation

Introduction
One of the convenient methods for the preparation of aldehydes and ketones is via hydration of alkynes. Hydroboration-oxidation of alkynes is an indirect hydration reaction in which an alkyne is treated with borane followed by oxidation with alkaline peroxide to form an enol that rapidly converts into an aldehyde or a ketone. Terminal alkynes form aldehydes, whereas internal alkynes give ketones as the final product.

Alcohols from Carbonyl Compounds: Reduction

Alcohols from Carbonyl Compounds: Reduction

Reduction is a simple strategy to convert a carbonyl group to a hydroxyl group. The three major pathways to reduce carbonyls to alcohols are catalytic hydrogenation, hydride reduction, and borane reduction.
Catalytic hydrogenation is similar to the reduction of an alkene or alkyne by adding H2 across the pi bond in the presence of transition metal catalysts like Raney Ni, Pd–C, Pt, or Ru. Aldehydes and ketones can be reduced by this method, often under mild to moderate heat (25–100°C) and...

Radical Substitution: Allylic Bromination

Radical Substitution: Allylic Bromination

In organic synthesis, the formation of products can be altered by changing the reaction conditions. For example, a dibromo addition product is formed when propene is treated with bromine at room temperature. In contrast, propene undergoes allylic substitution in non-polar solvents at high temperatures to give 3-bromopropene. In order to avoid the addition reaction, the bromine concentration must be kept as low as possible throughout the reaction. This can be achieved using N-bromosuccinimide...

Regioselectivity and Stereochemistry of Hydroboration

Regioselectivity and Stereochemistry of Hydroboration

A significant aspect of hydroboration–oxidation is the regio- and stereochemical outcome of the reaction.
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn...