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Un nuevo diseño de ligandos basado en la dispersión de Londres potencia los catalizadores de rueda de remolque de

Santanu Singha¹, Michael Buchsteiner¹, Giovanni Bistoni¹

¹Max-Planck-Institut für Kohlenforschung, 45470 Mülheim/Ruhr, Germany.

Journal of the American Chemical Society

|April 8, 2021

Resumen

Los nuevos catalizadores de bismuto y rodio con ligandos modificados por sililo muestran una selectividad superior y tasas de reacción más rápidas en las reacciones de carbenos. Las fuerzas de dispersión de Londres estabilizan la esfera del ligando quiral, mejorando el rendimiento del catalizador.

Área de la Ciencia:

Química organometálica
Catálisis
Química supramolecular

Sus antecedentes:

Los catalizadores quirales son cruciales para la síntesis asimétrica.
Las generaciones anteriores de catalizadores tenían limitaciones en la selectividad, las tasas de reacción y el alcance del sustrato.

Objetivo del estudio:

Desarrollar nuevos complejos heterobimetálicos de bismuto y rodio.
Investigar el impacto de los ligandos de fenilglicina sustituidos por sililo en la actividad catalítica y la selectividad.
Para aclarar las interacciones estabilizadoras dentro de la esfera del ligando quiral.

Principales métodos:

Síntesis de complejos heterobimetálicos de bismuto y rodio en ruedas de remo.
Caracterización experimental que incluye la cristalografía de rayos X.
Estudios computacionales (por ejemplo, DFT) para analizar la estabilización de ligandos e interacciones.

Principales resultados:

Los nuevos catalizadores muestran una selectividad sobresaliente en las reacciones donante/acceptora y donante/donante de carbenos.
Velocidades de reacción significativamente mejoradas y un alcance de sustrato más amplio en comparación con los catalizadores anteriores.
Los datos cristalográficos y computacionales revelan la estabilización de la esfera del ligando quiral por las interacciones de dispersión de Londres (LD) de los grupos silílicos periféricos.

Conclusiones:

Los catalizadores heterobimetálicos de bismuto y rodio funcionalizados con grupos TIPS ofrecen un rendimiento superior en la química de carbenos.
Las interacciones de dispersión de Londres juegan un papel clave en la estabilización del entorno quiral, lo que conduce a mejores resultados catalíticos.
Estos hallazgos allanan el camino para procesos catalíticos asimétricos más eficientes y versátiles.

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