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Una nueva y poderosa construcción de complejos policiclos quirales por una cascada catiónica catalizada por indio

Karavadhi Surendra¹, Wenwei Qiu, E J Corey

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

Journal of the American Chemical Society

|June 8, 2011

Resumen

Los catalizadores de indio (III) transforman eficazmente los compuestos quirales propargílicos en moléculas policíclicas complejas. Este método logra altos rendimientos y estereoselectividad, lo que permite la síntesis de intrincados sistemas de anillos fundidos.

Área de la Ciencia:

Química orgánica es la química orgánica.
La catálisis por catálisis.
Química sintética de la química sintética.

Sus antecedentes:

Los alcoholes propargílicos quirales y los éteres silílicos son valiosos intermediarios sintéticos.
Se demandan métodos eficientes para la construcción de sistemas policíclicos complejos con alto estereocontrol.

Objetivo del estudio:

Desarrollar un nuevo método catalítico para la síntesis de productos policíclicos.
Para utilizar haluros de indio (III) como catalizadores para la activación π de los alquinos.
Para lograr altos rendimientos y estereoselectividad en la formación de estructuras quirales complejas.

Principales métodos:

Utilizando el ioduro de indio (InI) y el bromuro de indio (InBr) como catalizadores.
Utilizando la activación π de los enlaces triples carbono-carbono (CC) en sustratos quirales propargílicos.
Investigando la conversión de los alcoholes propargílicos y éteres silílicos en compuestos policíclicos.

Principales resultados:

Se lograron excelentes rendimientos y una alta estereoselectividad en la síntesis de productos policíclicos.
El sistema catalítico sintetizó con éxito sistemas de anillos quirales hexacíclicos fusionados.
Se crearon múltiples estereocentros nuevos con un control preciso.

Conclusiones:

Los catalizadores de indio (III) son muy eficaces para la activación π de los alquinos.
Esta metodología proporciona una ruta poderosa a moléculas policíclicas quirales complejas.
El alcance y la eficiencia del método se demuestran a través de varios ejemplos.

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