Video Experimental Relacionado
Updated: Jun 29, 2026
08:56
Synthesis of a Borylated Ibuprofen Derivative Through Suzuki Cross-Coupling and Alkene Boracarboxylation Reactions
Published on: November 30, 2022
Síntesis en varias etapas de ácidos borónicos complejos a partir de boronatos MIDA simples
Eric P Gillis1, Martin D Burke
1Roger Adams Laboratory, Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
Journal of the American Chemical Society
|October 8, 2008
Resumen
Los boronatos MIDA estables en el aire superan las limitaciones de la química sintética. Estos compuestos estables permiten la síntesis en múltiples etapas de bloques de construcción complejos de ácido borónico, facilitando la síntesis orgánica avanzada.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Química sintética de la química sintética.
- Química Medicinal La Química Medicinal es un campo de estudio de la química medicinal.
Sus antecedentes:
- Los ácidos borónicos son cruciales en la síntesis orgánica, pero son sensibles a muchos reactivos.
- Su inestabilidad requiere una introducción tardía, lo que limita las estrategias sintéticas.
Objetivo del estudio:
- Desarrollar sustitutos estables del ácido borónico para la síntesis de moléculas complejas.
- Para permitir la síntesis en varios pasos utilizando bloques de construcción de ácido borónico.
Principales métodos:
- Síntesis y caracterización de los boronatos de ácido N-metilminodiacético (MIDA).
- Estudios de compatibilidad con reactivos sintéticos comunes.
- Cristalografía de rayos X y espectroscopia de RMN a temperatura variable.
- Síntesis total de (+) -crocacina C con el uso de boronatos de MIDA.
Principales resultados:
- Los boronatos MIDA exhiben una estabilidad excepcional al aire y a los reactivos comunes.
- La estabilidad se atribuye a la inaccesibilidad cinética del par solitario p-orbital de boro y nitrógeno.
- Utilidad demostrada en reacciones iterativas de acoplamiento cruzado.
- Se logró una síntesis total modular de (+) -crocacina C.
Conclusiones:
- Los boronatos MIDA representan un avance significativo en el manejo y la utilización de los ácidos borónicos.
- Esta metodología simplifica la síntesis de complejos derivados del ácido borónico.
- Permite la construcción eficiente de intrincadas arquitecturas moleculares, incluidos los productos naturales.
Videos de Conceptos Relacionados
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.
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.
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.
02:15Preparation of Alcohols via Addition Reactions
Overview
The acid-catalyzed addition of water to the double bond of alkenes is a large-scale industrial method used to synthesize low-molecular-weight alcohols. An acidic atmosphere is required to allow the hydrogen in the water molecule to act as an electrophile and attack the double bond in an alkene. The addition of a proton to the double bond creates a carbocation intermediate. The proton preferentially bonds to the less substituted end of the double bond to create a more stable carbocation...
The acid-catalyzed addition of water to the double bond of alkenes is a large-scale industrial method used to synthesize low-molecular-weight alcohols. An acidic atmosphere is required to allow the hydrogen in the water molecule to act as an electrophile and attack the double bond in an alkene. The addition of a proton to the double bond creates a carbocation intermediate. The proton preferentially bonds to the less substituted end of the double bond to create a more stable carbocation...
03:08Rate-Determining Steps
Relating Reaction Mechanisms
In a multistep reaction mechanism, one of the elementary steps progresses significantly slower than the others. This slowest step is called the rate-limiting step (or rate-determining step). A reaction cannot proceed faster than its slowest step, and hence, the rate-determining step limits the overall reaction rate.
The concept of rate-determining step can be understood from the analogy of a 4-lane freeway with a short-stretch of traffic-bottleneck caused due to...
In a multistep reaction mechanism, one of the elementary steps progresses significantly slower than the others. This slowest step is called the rate-limiting step (or rate-determining step). A reaction cannot proceed faster than its slowest step, and hence, the rate-determining step limits the overall reaction rate.
The concept of rate-determining step can be understood from the analogy of a 4-lane freeway with a short-stretch of traffic-bottleneck caused due to...
02:23Alcohols 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...
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...