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Sustitución alilica catalizada por el paladio con nucleófilos basados en (η6-areno-CH2Z) Cr (((CO) ((3))

Jiadi Zhang¹, Corneliu Stanciu, Beibei Wang

¹Roy and Diana Vagelos Laboratories, Penn/Merck Laboratory for High-Throughput Experimentation, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104-6323, USA.

Journal of the American Chemical Society

|November 4, 2011

Resumen

Este estudio introduce un nuevo método catalizado por el paladio para la sustitución de aliloides utilizando nucleófilos bencílicos simples. Este enfoque proporciona un acceso eficiente a valiosos motivos de "α-2-propenil bencilo" que se encuentran en productos naturales y compuestos bioactivos.

Área de la Ciencia:

Química orgánica es la química orgánica.
La catálisis de la catálisis.
Metodología sintética de la metodología sintética.

Sus antecedentes:

La sustitución alilica Tsuji-Trost catalizada por el paladio está bien establecida.
No existen métodos generales para emplear nucleófilos bencílicos simples.
El acceso a los motivos de "α-2-propenil bencil" es importante para los compuestos bioactivos.

Objetivo del estudio:

Desarrollar un método general catalizado por el paladio para la sustitución de aliloides utilizando nucleófilos bencílicos simples.
Para permitir la síntesis eficiente de las estructuras de "α-2-propenil bencil".
Ampliar el alcance de los nucleófilos en las reacciones de sustitución alelica.

Principales métodos:

La alilación catalizada por el paladio de pronucleófilos derivados del tolueno activados por el tricarbonilcromo.
Uso de nucleófilos generados in situ (η(6)-C(6)H(5)CHLiR)Cr(CO)(3) con varios electrófilos alelicos.
Experimentación de alto rendimiento (HTE, por sus siglas en inglés) para el cribado de catalizadores, identificando Xantphos/palladio.
Utilizó derivados de benzilamina y éter como pronucleófilos.

Principales resultados:

Exitosa alilación catalizada por el paladio de pronucleófilos derivados del tolueno.
Identificación de Xantphos/palladio como un catalizador general.
Utilidad demostrada con electrófilos alelicos cíclicos y acíclicos.
Se obtuvieron excelentes rendimientos para la formación de enlaces C-C α a los heteroátomos utilizando derivados de benzilamina y éter.
Desarrolló un procedimiento de sustitución y desmetalización de alelo en tándem para productos libres de metales.

Conclusiones:

Se ha desarrollado un método novedoso y general catalizado por el paladio para la sustitución de aliloides utilizando nucleófilos bencílicos simples.
El método proporciona un acceso eficiente a valiosos motivos de "α-2-propenil bencilo".
Este enfoque amplía la utilidad sintética de las reacciones de sustitución de alelo.

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