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Empujar la poliborilación C-H catalizada por Ir de los compuestos aromáticos a su máxima capacidad mediante la
Maria N Eliseeva1, Lawrence T Scott
1Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467-3860, USA.
Journal of the American Chemical Society
|September 6, 2012
Resumen
Pequeñas cantidades de base facilitan la poliborilación C-H catalizada por iridio de los compuestos aromáticos. Esto permite la síntesis de moléculas altamente boriladas como el pentakis (Bpin) corannuleno a través de un reposicionamiento controlado del sustituyente.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- La catálisis es la catálisis.
- Química orgánica sintética y orgánica.
Sus antecedentes:
- La borilación C-H catalizada por iridio es una herramienta poderosa para la funcionalización de compuestos aromáticos.
- El control de la regioselectividad y el grado de borilación sigue siendo un desafío.
Objetivo del estudio:
- Investigar el papel de las bases en la poliborilación C-H catalizada por Ir.
- Desarrollar un método para sintetizar compuestos aromáticos altamente borilados.
Principales métodos:
- Utilizando pequeñas cantidades de base (t-butóxido de potasio o metóxido de sodio) en reacciones catalizadas por Ir.
- Utilizando el exceso de agente borilador, bis (((pinacolato) diborano (B ((2) pin ((2)).
- Analizando el equilibrio de productos favorecidos cinéticamente.
Principales resultados:
- Las bases promueven el equilibrio de los productos de borilación favorecidos cinéticamente.
- La desborilación/reborilación repetitiva lleva al reposicionamiento de los sustituyentes de Bpin.
- Se logró una síntesis de alto rendimiento en un solo paso de 1,3,5,7,9-pentakis ((Bpin) corannulene.
Conclusiones:
- Las bases son cruciales para lograr el control termodinámico en la poliborilación C-H catalizada por Ir.
- Esta estrategia permite la síntesis de sistemas aromáticos complejos y altamente sustituidos.
- Amplia la utilidad de la borilación catalizada por Ir para crear moléculas poliboriladas.
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