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Aspartyl β-Turn-Based Dirhodium ((II) Metallopeptides para la Aminación Bencílica C ((sp3) -H: Enantioselectividad y
Naudin van den Heuvel1, Savannah M Mason1, Brandon Q Mercado1
1Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States.
Journal of the American Chemical Society
|May 22, 2023
Resumen
Los nuevos catalizadores de dirodio basados en péptidos permiten una aminación altamente enantioselectiva de enlaces C sp 3 H, superando las limitaciones de los sistemas existentes para la síntesis de moléculas complejas.
Área de la Ciencia:
- Química orgánica
- Catálisis
- Química supramolecular
Sus antecedentes:
- La aminación de enlaces C ((sp3) -H es crucial para la incorporación de nitrógeno en moléculas orgánicas.
- El logro del control de sitio y enantio en las reacciones de aminación sigue siendo un desafío significativo.
- Los sistemas de catalizadores existentes luchan con estructuras moleculares complejas.
Objetivo del estudio:
- Desarrollar una nueva clase de catalizadores quirales de dirodio para la aminación enantioselectiva de C sp 3 H.
- Crear una plataforma modular para generar diversas bibliotecas de catalizadores.
- Investigar las propiedades estructurales y catalíticas de estos nuevos catalizadores.
Principales métodos:
- Síntesis de complejos de dirodio a base de péptidos a partir de tetrámeros que contienen ácido aspártico.
- Generación de una biblioteca de 38 catalizadores quirales distintos.
- Cristalografía de rayos X para determinar la estructura de un complejo de dirodio (II) tetra-aspartato.
- Prueba del rendimiento del catalizador en la aminación bencílica enantioselectiva C ((sp3) -H y en la aminación de N-alquilación intermolecular.
Principales resultados:
- Se estableció un sistema modular para la generación rápida de bibliotecas de catalizadores.
- La primera estructura cristalina de un complejo de tetra-aspartato de dirodio reveló una conformación de giro β retenida y centros de rodio no equivalentes.
- Se logró una enantioselectividad de última generación (hasta 95,54,5 er) en la aminación bencílica C ((sp3) -H, incluso para sustratos difíciles.
- Los catalizadores demostraron eficacia en la aminación intermolecular de las N-alquilamidas, produciendo 1,1-diaminas.
Conclusiones:
- Los complejos de dirodio (II) basados en péptidos ofrecen una plataforma poderosa y versátil para la aminación C (sp3) -H enantioselectiva.
- Las características estructurales únicas de estos catalizadores contribuyen a su alta selectividad y reactividad.
- Este enfoque hace avanzar la síntesis de moléculas orgánicas complejas que contienen nitrógeno.
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