Activación remota de C-H enantioselectiva dirigida por un catión quiral
Georgi R Genov1, James L Douthwaite1, Antti S K Lahdenperä1
1Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK.
Science (New York, N.Y.)
|March 14, 2020
Resumen
Los investigadores desarrollaron un nuevo método para la borilación enantioselectiva de C-H utilizando complejos de iridio con ligandos de bipiridina aniónica y cationes quirales. Esta estrategia permite la inducción asimétrica en las reacciones de desimetrización, ofreciendo un nuevo enfoque para la catálisis quiral.
Área de la Ciencia:
- Química organometálica
- Catálisis asimétrica
- Química orgánica sintética
Sus antecedentes:
- Los cationes quirales son organocatalizadores establecidos.
- La catálisis enantioselectiva de metales de transición utilizando cationes quirales está poco explorada.
- Las estrategias invertidas de carga con aniones quirales son exitosas.
Objetivo del estudio:
- Desarrollar una nueva estrategia para la catálisis enantioselectiva de metales de transición.
- Para utilizar ligandos aniónicos emparejados con cationes quirales.
- Para lograr una inducción asimétrica en las reacciones de borilación C-H.
Principales métodos:
- Modificación aniónica de un ligando de la bipiridina.
- Formación de complejos de iridio con el ligando aniónico.
- Combinación de complejos de iridio con un catión derivado de quinina quiral.
- Aplicación en la borilación C-H enantioselectiva para la desimetrización.
Principales resultados:
- Aplicación exitosa de complejos de iridio emparejados con iones para la inducción asimétrica.
- Desimetrización demostrada de los motivos de diarilo geminados en los centros de carbono y fósforo.
- Se ha logrado una borilación enantioselectiva de C-H con un control asimétrico de largo alcance.
Conclusiones:
- La estrategia presentada ofrece una nueva vía para la catálisis enantioselectiva utilizando ligandos aniónicos y cationes quirales.
- Este enfoque es potencialmente aplicable a una amplia gama de ligandos.
- Destaca el potencial de la inversión de carga en la catálisis asimétrica.
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