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Polarizar la ciclización de Nazarov: catálisis eficiente bajo condiciones suaves

Wei He¹, Xiufeng Sun, Alison J Frontier

¹Department of Chemistry, University of Rochester, Rochester, NY 14627, USA.

Journal of the American Chemical Society

|November 20, 2003

Resumen

Las cetonas de divinyl sustituidas se someten eficientemente a la ciclización de Nazarov utilizando la catálisis del triflato de cobre. Esta reacción produce un único isómero de ciclopentenona, cuya eficiencia depende de los efectos electrónicos sustituyentes.

Área de la Ciencia:

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

Sus antecedentes:

La ciclización de Nazarov es una reacción clave para sintetizar las ciclopentenonas.
La comprensión de los efectos de sustitución es crucial para controlar la regionalidad y la estereoselectividad.

Objetivo del estudio:

Para investigar la ciclización de Nazarov de las cetonas divinyl sustituidas.
Explorar el papel de la polarización electrónica en la eficiencia de reacción y la selectividad.

Principales métodos:

Utilizado triflato catalítico de cobre (2 mol %) para la ciclización de Nazarov.
Estudió las cetonas alfa-carbomethoxy divinyl como sustratos.

Principales resultados:

Se logró una eficiente ciclización de Nazarov de las cetonas alfa-carbometoxidivinilo.
Se obtiene un único regio- y estereoisómero de ciclopentenona.
Eficiencia de ciclización correlacionada con la polarización del sustituyente del sistema pi del intermedio catiónico.

Conclusiones:

El triflato de cobre catalítico es efectivo para la ciclización de Nazarov de estos sustratos.
Las propiedades electrónicas de los sustitutos influyen significativamente en el resultado de la ciclización de Nazarov.
Los hallazgos proporcionan información sobre el control de la síntesis de ciclopentenona.

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