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Una bromolactonización enantiodivergente controlada por catalizador

Yuk-Cheung Chan¹, Xinyan Wang¹, Ying-Pong Lam¹

¹Department of Chemistry and State Key Laboratory of Synthetic Chemistry, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, China.

Journal of the American Chemical Society

|August 5, 2021

Resumen

Este estudio introduce un nuevo método controlado por catalizador para la bromolactonización asimétrica de ácidos olefínicos. Un simple cambio en la estructura del catalizador invierte completamente el resultado estereocímico, produciendo lactonas enantioméricamente puras.

Área de la Ciencia:

Química orgánica
Catálisis asimétrica
Metodología sintética

Sus antecedentes:

La síntesis enantioselectiva es crucial para los productos farmacéuticos y agroquímicos.
Desarrollar catalizadores que controlen la estereoquímica es un desafío clave.
La bromolactonización ofrece una vía para obtener valiosos productos de lactona.

Objetivo del estudio:

Desarrollar una bromolactonización enantidivergente controlada por catalizador de ácidos olefínicos.
Investigar el efecto de la estructura del catalizador en el resultado estereoquímico.
Para aclarar el mecanismo de reacción.

Principales métodos:

Se han utilizado catalizadores de aminoamidas derivados de la quinina.
Se ha realizado la bromolactonización enantiodivergente de ácidos olefínicos.
Estudios mecanicistas realizados, incluidos experimentos químicos y cálculos de DFT.

Principales resultados:

Se ha logrado una síntesis enantidivergente de lactonas controlada por catalizadores.
Demostró un cambio completo en la inducción asimétrica mediante la alteración de los sustituyentes del catalizador.
Se obtienen las lactonas deseadas con buena enantioselectividad y rendimiento.

Conclusiones:

Los efectos estéricos y electrónicos de los sustituyentes del catalizador influyen significativamente en el mecanismo de reacción.
Este trabajo proporciona un método versátil para acceder a las lactonas enantioméricamente enriquecidas.
El diseño del catalizador es crítico para controlar la estereoquímica en la síntesis orgánica.

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