Video Experimental Relacionado

Updated: Nov 4, 2025

Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine

Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine

Published on: June 13, 2022

Síntesis total enantioselectiva de la (+) euforicanina A

Moritz J Classen¹, Markus N A Böcker¹, Remo Roth¹

¹ETH Zürich, Department of Chemistry and Applied Biosciences, Laboratory of Organic Chemistry, Vladimir Prelog Weg 3, 8093 Zürich, Switzerland.

Journal of the American Chemical Society

|May 27, 2021

Resumen

Los investigadores lograron la primera síntesis total de (+) euforicanina A, un producto natural complejo. Una reacción clave mediada por SmI2 construyó eficientemente su núcleo tetraciclico único, lo que permitió nuevos avances sintéticos.

Área de la Ciencia:

Química orgánica
Síntesis de productos naturales
Desarrollo de la metodología

Sus antecedentes:

Los productos naturales derivados del ingenano representan una clase estructuralmente diversa de compuestos de interés biológico significativo.
El intrincado esqueleto tetraciclico fundido de (+) -euforikanina A presenta un formidable desafío para la síntesis total.
El desarrollo de estrategias sintéticas eficientes y estereoselectivas es crucial para acceder a productos naturales complejos.

Objetivo del estudio:

Se informará de la primera síntesis total de (+) euforicanina A.
Para establecer una ruta sintética robusta y escalable a este complejo derivado ingenano.
Mostrar la utilidad de nuevas metodologías sintéticas en la construcción de sistemas de anillos altamente fusionados.

Principales métodos:

Se empleó una reacción de cetilenoato mediada por SmI2 para la formación de enlaces C-C clave y la construcción de anillos.
Se utilizó una estrategia de ciclización de polaridad inversa para ensamblar el marco tetraciclico central.
Se implementaron transformaciones quimioselectivas de etapa tardía, incluida la generación de litio vinílico y la ciclización intramolecular, para completar la síntesis.

Principales resultados:

Se logró con éxito la primera síntesis total de (+) - euforicanina A.
La reacción mediada por SmI2 proporcionó un acceso rápido a dos anillos en un solo paso con un excelente rendimiento y diastereoselectividad.
La eficiencia de la funcionalización tardía permitió la construcción del desafiante anillo B.

Conclusiones:

La vía sintética desarrollada proporciona una vía viable para la preparación de (+) -euforikanina A.
El estudio destaca el poder de las reacciones mediadas por radicales y las ciclizaciones de polaridad inversa en la síntesis de moléculas complejas.
Este trabajo amplía la caja de herramientas sintéticas para acceder a productos naturales a base de ingenano y sus análogos.

Más Videos Relacionados

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones

Published on: February 7, 2019

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles

Published on: August 22, 2018

Videos de Conceptos Relacionados

Synthesis of α-Substituted Carbonyl Compounds: The Stork Enamine Reaction

Synthesis of α-Substituted Carbonyl Compounds: The Stork Enamine Reaction

α-Substituted ketones or aldehydes can be synthesized from enamines by the Stork enamine reaction, named after its pioneer Gilbert Stork. Enamines are useful synthetic intermediates where the lone pair on nitrogen is in conjugation with the C=C bond. They resemble enolate ions, as the resonance forms of both species have a nucleophilic α carbon.

Preparation of 1° Amines: Gabriel Synthesis

Preparation of 1° Amines: Gabriel Synthesis

Direct alkylation is not a suitable method for synthesizing amines because it produces polyalkylated products. Gabriel synthesis is the most preferred method to exclusively make primary amines. The method uses phthalimide, which contains a protected form of nitrogen that participates in alkylation only once to predominantly give primary amines.
Strong bases like NaOH or KOH deprotonate the phthalimide to form the corresponding anion, which acts as a nucleophile. Further, the anion attacks an...

Sharpless Epoxidation

Sharpless Epoxidation

The conversion of allylic alcohols into epoxides using the chiral catalyst was discovered by K. Barry Sharpless and is known as Sharpless epoxidation. The use of a chiral catalyst enables the formation of one enantiomer of the product in excess. This chiral catalyst is mainly a chiral complex of titanium tetraisopropoxide and tartrate ester (specific stereoisomer). The stereoisomer used in the chiral catalyst dictates the formation of the enantiomer of the product. In other words, the use of...

Preparation of 1° Amines: Hofmann and Curtius Rearrangement Overview

Preparation of 1° Amines: Hofmann and Curtius Rearrangement Overview

In the presence of an aqueous base and a halogen, primary amides can lose the carbonyl (as carbon dioxide) and undergo rearrangement to form primary amines. This reaction, called the Hofmann rearrangement, can produce primary amines (aryl and alkyl) in high yields without contamination by secondary and tertiary amines.

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...

Regioselective Formation of Enolates

Regioselective Formation of Enolates

As depicted in the figure below, the unsymmetrical ketones can form two possible enolates: less substituted or more substituted enolates. Usually, the thermodynamic enolates are formed from the more substituted α-carbon atom, while the kinetic enolates are formed faster by deprotonation from the less substituted position. The thermodynamic enolates have lower energy, so they are more stable. But the energy required to form kinetic enolates is less.