Video Experimental Relacionado

Updated: Mar 25, 2026

[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

Acoplamientos asimétricos C-N catalizados por cobre inducidos por la luz visible

Quirin M Kainz¹, Carson D Matier¹, Agnieszka Bartoszewicz¹

¹Division of Chemistry and Chemical Engineering, California Institute of Technology (Caltech), Pasadena, CA 91125, USA.

Science (New York, N.Y.)

|February 26, 2016

Resumen

Este estudio introduce una nueva reacción fotoinducida catalizada por cobre para crear moléculas complejas. Este método genera eficientemente estereocentros altamente enantioselectivos y completamente sustituidos a partir de precursores simples que utilizan cobre abundante en la Tierra.

Área de la Ciencia:

Química orgánica
Fotocatálisis
Síntesis asimétrica

Sus antecedentes:

La catálisis del cobre es un campo bien establecido.
El uso del cobre como fotocatalizador está poco explorado.
El desarrollo de métodos eficientes para crear estereocentros es crucial en la síntesis orgánica.

Objetivo del estudio:

Para explorar el potencial del cobre como un fotocatalizador.
Desarrollar un método fotoinducido catalizado por el cobre para acoplar cloruros de alquilo terciarios con aminas.
Para lograr una alta enantioselectividad en la síntesis de estereocentros completamente sustituidos.

Principales métodos:

Utilizó una reacción de acoplamiento fotoinducida catalizada por cobre.
Se emplean electrofiles y aminas de cloruro de alquilo racémica terciaria fácilmente disponibles.
Se llevó a cabo la reacción a -40°C bajo irradiación de diodo emisor de luz azul.
Aprovechó un solo metal de transición abundante en la Tierra para la catálisis y la inducción asimétrica.

Principales resultados:

Se generaron con éxito estereocentros completamente sustituidos con alta enantioselectividad.
Se ha demostrado un mecanismo enantioconvergente que convierte el material de partida racémico en un único enantiómero de producto.
La reacción se desarrolló eficientemente en condiciones suaves (-40°C, LED azul).

Conclusiones:

El cobre puede servir efectivamente como un fotocatalizador para la síntesis asimétrica.
Este método proporciona una nueva ruta a los estereocentros terciarios enriquecidos enantioméricamente.
El uso de cobre abundante en la Tierra ofrece un enfoque sostenible para la síntesis de moléculas complejas.

Más Videos Relacionados

Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions

Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions

Published on: July 17, 2020

Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units

Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units

Published on: September 18, 2016

Videos de Conceptos Relacionados

Cycloaddition Reactions: MO Requirements for Photochemical Activation

Cycloaddition Reactions: MO Requirements for Photochemical Activation

Some cycloaddition reactions are activated by heat, while others are initiated by light. For example, a [2 + 2] cycloaddition between two ethylene molecules occurs only in the presence of light. It is photochemically allowed but thermally forbidden.

Photochemical Electrocyclic Reactions: Stereochemistry

Photochemical Electrocyclic Reactions: Stereochemistry

The absorption of UV–visible light by conjugated systems causes the promotion of an electron from the ground state to the excited state. Consequently, photochemical electrocyclic reactions proceed via the excited-state HOMO rather than the ground-state HOMO. Since the ground- and excited-state HOMOs have different symmetries, the stereochemical outcome of electrocyclic reactions depends on the mode of activation; i.e., thermal or photochemical.
Selection Rules: Photochemical Activation

Reduction of Alkenes: Asymmetric Catalytic Hydrogenation

Reduction of Alkenes: Asymmetric Catalytic Hydrogenation

Catalytic hydrogenation of alkenes is a transition-metal catalyzed reduction of the double bond using molecular hydrogen to give alkanes. The mode of hydrogen addition follows syn stereochemistry.
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...

Cycloaddition Reactions: Overview

Cycloaddition Reactions: Overview

Cycloadditions are one of the most valuable and effective synthesis routes to form cyclic compounds. These are concerted pericyclic reactions between two unsaturated compounds resulting in a cyclic product with two new σ bonds formed at the expense of π bonds. The [4 + 2] cycloaddition, known as the Diels–Alder reaction, is the most common. The other example is a [2 + 2] cycloaddition.

Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide

Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide

Alkenes are converted to 1,2-diols or glycols through a process called dihydroxylation. It involves the addition of two hydroxyl groups across the double bond with two different stereochemical approaches, namely anti and syn. Dihydroxylation using osmium tetroxide progresses with syn stereochemistry.

Thermal and Photochemical Electrocyclic Reactions: Overview

Thermal and Photochemical Electrocyclic Reactions: Overview

Electrocyclic reactions are reversible reactions. They involve an intramolecular cyclization or ring-opening of a conjugated polyene. Shown below are two examples of electrocyclic reactions. In the first reaction, the formation of the cyclic product is favored. In contrast, in the second reaction, ring-opening is favored due to the high ring strain associated with cyclobutene formation.