Video Experimental Relacionado
Updated: Jun 5, 2026
08:56
Synthesis of a Borylated Ibuprofen Derivative Through Suzuki Cross-Coupling and Alkene Boracarboxylation Reactions
Published on: November 30, 2022
La arilación catalizada por el rodio (III) de Boc-iminas a través de la funcionalización del enlace C-H
Andy S Tsai1, Michael E Tauchert, Robert G Bergman
1Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States.
Journal of the American Chemical Society
|January 6, 2011
Resumen
Este estudio introduce la primera arylación catalizada por el rodio de iminas utilizando la funcionalización de enlaces C-H. El método produce eficientemente N-Boc-aminas con ramificación arilo, compatibles con diversos grupos funcionales.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis de la catálisis.
- Metodología sintética de la metodología sintética.
Sus antecedentes:
- Las iminas son versátiles intermediarios sintéticos.
- La funcionalización C-H ofrece rutas atómico-económicas para moléculas complejas.
- La arilación directa de las iminas sigue siendo un desafío sintético.
Objetivo del estudio:
- Desarrollar la primera arilación directa catalizada por el rodio de iminas a través de la funcionalización de enlaces C-H.
- Para explorar el alcance y las limitaciones de esta nueva transformación sintética.
- Para identificar los parámetros clave de reacción para una arilación eficiente.
Principales métodos:
- La catálisis del rodio.
- La activación/funcionalización de C-H.
- El uso de extractores de haluros sin coordinación.
- Estudios de optimización de la reacción.
Principales resultados:
- Arylación exitosa catalizada por el rodio de las iminas a través de la funcionalización directa C-H.
- Formación de N-Boc-aminas ramificadas en arilo como los productos primarios.
- Demostración de la tolerancia del grupo funcional amplio.
- Identificación de los abstractores de haluros no coordinadores como cruciales para la reactividad.
Conclusiones:
- Se ha establecido un método nuevo y eficiente para la arilación directa de iminas.
- Este enfoque de funcionalización C-H proporciona acceso a valiosas aminas arilo-branqueadas.
- La metodología exhibe un potencial significativo para la síntesis de moléculas complejas.
![[(DPEPhos)(bcp)Cu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F59739.jpg&w=3840&q=50)
Videos de Conceptos Relacionados
02:47Alkynes 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.
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.
02:36Regioselectivity 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 stereochemistry.
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 stereochemistry.
03:08Hydroboration-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.
01:14Nucleophilic Aromatic Substitution of Aryldiazonium Salts: Aromatic SN1
Treating arylamines with nitrous acid gives aryldiazonium salts that are effective substrates in nucleophilic aromatic substitution reactions. The diazonio group in these salts can be easily displaced by different nucleophiles, yielding a wide variety of substituted benzenes. The leaving group departs as nitrogen gas, and this easy elimination is the driving force for the substitution reaction.
In the Sandmeyer reaction, for example, the diazonio group is replaced by a chloro, bromo, or cyano...
In the Sandmeyer reaction, for example, the diazonio group is replaced by a chloro, bromo, or cyano...
01:15α-Bromination of Carboxylic Acids: Hell–Volhard–Zelinski Reaction
The method to achieve α-brominated carboxylic acids using a mixture of phosphorus tribromide and bromine is known as the Hell–Volhard–Zelinski reaction. The reaction is catalyzed by phosphorus tribromide, which can be used directly or produced in situ from red phosphorus and bromine. The mechanism comprises PBr3 catalyzed conversion of acid to acid bromide and hydrogen bromide. The acid bromide enolizes to its enol form in the presence of HBr. The nucleophilic enol attacks the bromine molecule...
02:35Electrophilic Addition to Alkynes: Hydrohalogenation
Electrophilic addition of hydrogen halides, HX (X = Cl, Br or I) to alkenes forms alkyl halides as per Markovnikov's rule, where the hydrogen gets added to the less substituted carbon of the double bond. Hydrohalogenation of alkynes takes place in a similar manner, with the first addition of HX forming a vinyl halide and the second giving a geminal dihalide.