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Transamidación eficiente de las carboxamidas primarias por activación in situ con N,N-dialquilformamida

Thomas A Dineen¹, Matthew A Zajac, Andrew G Myers

¹Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA.

Journal of the American Chemical Society

|December 15, 2006

Resumen

Los nuevos métodos para la síntesis de amidas permiten una transamidación eficiente de las amidas primarias. Estos protocolos utilizan N,N-dialquilformamida dimetilacetales y aditivos de ácido de Lewis para reacciones de intercambio de amidas de alto rendimiento.

Área de la Ciencia:

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

Sus antecedentes:

La formación de enlaces amídicos es crucial en la síntesis orgánica.
La transamidación ofrece una ruta alternativa a las amidas.
Los métodos existentes para la transamidación de amida tienen limitaciones.

Objetivo del estudio:

Desarrollar nuevos protocolos para la transamidación eficiente de las amidas primarias.
Explorar el uso de aditivos de ácido de Lewis para facilitar las reacciones de intercambio de amidas.

Principales métodos:

Activación de amidas primarias mediante el uso de N,N-dialquilformamida dimetilacetales para formar N'-acil-N,N-dialquilformamidina intermedios.
Dos protocolos distintos: uno que implica la purificación de los productos intermedios, el otro la generación in situ.
Utilizando ácidos de Lewis como el triflato de escandio o el cloruro de zirconio para promover la transferencia de acilo.

Principales resultados:

Los altos rendimientos de amidas secundarias y terciarias se obtienen a través de la transamidation.
Demostró la eficacia de los aditivos de ácido de Lewis para superar la transferencia irreversible de amidinilo.
Aplicación exitosa a una variedad de amidas y aminas primarias.

Conclusiones:

Desarrolló dos protocolos eficientes y versátiles para la transamidación de amida.
Estos métodos proporcionan nuevas herramientas valiosas para la síntesis de amidas.
El uso de ácidos de Lewis es clave para el éxito de estas reacciones de transamidation.

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