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Alquilboración selectiva y sin metales de transición de los alquinos

Marina Nogami¹, Keiichi Hirano¹, Misae Kanai²

¹Graduate School of Pharmaceutical Sciences, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.

Journal of the American Chemical Society

|August 15, 2017

Resumen

Este estudio introduce una nueva reacción de alquilboración sin metales de transición para los alquinos. El nuevo método de carboboración produce valiosos 4-alquinyl-1,2-oxaborol-2(5H) -ols con propiedades fluorescentes.

Área de la Ciencia:

Química orgánica
Química del organoboron
Catálisis

Sus antecedentes:

Las reacciones de alquinilboración son cruciales para sintetizar moléculas orgánicas complejas.
Por lo general, se requieren catalizadores de metales de transición para una alquilboración eficiente.
El desarrollo de alternativas sin metales ofrece rutas sintéticas más ecológicas y potencialmente más rentables.

Objetivo del estudio:

Desarrollar la primera alquinilación libre de metales de transición y trans selectiva de los alquinos.
Para explorar la utilidad de los alcoholes propargílicos en la activación de los alquinilboronatos.
Sintetizar y caracterizar los nuevos 4-alquinil-1,2-oxaborol-2(5H) -ols.

Principales métodos:

La activación pseudo-intramolecular de los alquinilboronatos mediante el uso de alcoholes propargílicos.
Se han optimizado las condiciones de reacción de carboboración.
Caracterización del producto mediante métodos espectroscópicos.

Principales resultados:

Desarrollo exitoso de una reacción de alquilboración trans selectiva sin metales de transición.
Formación de 4-alquinyl-1,2-oxaborol-2(5H) -ols mediante carboboración.
Los compuestos sintetizados exhiben una fuerte fluorescencia violeta-azul.

Conclusiones:

Este trabajo presenta un avance significativo en la química del organoboron.
El método desarrollado proporciona acceso a bloques de construcción valiosos y fluorescentes.
La naturaleza libre de metales de la reacción abre nuevas vías para la síntesis sostenible.

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