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El descubrimiento y desarrollo de una reacción de transferencia de alquilo N→C catalizada por iridio
Erin C Boddie1, Phillippa Cooper2, L Anders Hammarback1
1Department of Chemistry, University of Liverpool, Crown Street, Liverpool, L69 7ZD, UK.
Angewandte Chemie (International ed. in English)
|August 28, 2025
Resumen
Este estudio demuestra las reacciones de transferencia de alquilo catalizadas por iridio en las amidas de arilo. Estas reacciones permiten la introducción de grupos ortoalquilo, logrando resultados enantioconvergentes con diversos sustratos.
Área de la Ciencia:
- Química orgánica
- Catálisis
- Metodología sintética
Sus antecedentes:
- Las amidas de arilo terciarias son intermediarios sintéticos versátiles.
- La introducción de sustituyentes ortoalquilo puede ser un desafío.
- La funcionalización estereoselectiva de los enlaces C-H es un área clave en la síntesis orgánica.
Objetivo del estudio:
- Desarrollar nuevos métodos catalizados por iridio para la transferencia de N-alquilo a amidas de arilo.
- Para lograr la ortoalquilación enantioconvergente de los anillos aromáticos.
- Para permitir la síntesis de valiosos compuestos aromáticos ortoalquilados.
Principales métodos:
- Funcionalización C-H catalizada por el iridio.
- Uso de un ligando homoquiral de difosfonita.
- Optimización de las condiciones de reacción para la transferencia de alquilo.
Principales resultados:
- Transferencia exitosa de N-2° y N-3° alquilo de las amidas de arilo terciarias a los enlaces C-H de orto-arilo.
- Demostración de la enantioconvergencia para los sustituyentes de 2o-alquilo no definidos estereológicamente.
- Desarrollo de la transferencia de N-2o alquilo intermolecular para la ortoalquilación.
Conclusiones:
- El sistema catalizado por Ir desarrollado proporciona una ruta eficiente para la ortoalquilación.
- El método ofrece una herramienta valiosa para introducir grupos ortoalquilo desafiantes.
- La transferencia de alquilo enantioconvergente expande las posibilidades sintéticas en química orgánica.
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