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Updated: Jan 9, 2026

Retropinacol/Cross-pinacol Coupling Reactions - A Catalytic Access to 1,2-Unsymmetrical Diols

Retropinacol/Cross-pinacol Coupling Reactions - A Catalytic Access to 1,2-Unsymmetrical Diols

Published on: April 4, 2014

Acoplamiento catalítico enantioselectivo entre nucleófilos a través del tautomerismo de valencia

Zhaofei Zhang¹, Arman Khosravi¹, Jagrut A Shah²

¹James Tarpo Jr. and Margaret Tarpo Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana 47907, United States.

Journal of the American Chemical Society

|December 10, 2025

Resumen

Este estudio introduce un nuevo sistema catalítico dual para el acoplamiento cruzado nucleófilo enantioselectivo, utilizando tautomerismo de valencia de un electrón para crear moléculas complejas con estereocentros cuaternarios de manera eficiente.

Área de la Ciencia:

Química orgánica
Catálisis
Síntesis asimétrica

Sus antecedentes:

El tautomerismo de valencia está poco explorado en la catálisis asimétrica en comparación con el tautomerismo prototrópico.
Se necesitan nuevos métodos catalíticos para crear arquitecturas moleculares complejas.

Objetivo del estudio:

Para aprovechar el tautomerismo de valencia de un electrón para el acoplamiento enantioselectivo cruzado de nucleófilos (CNC).
Desarrollar un método libre de oxidantes para acoplar diversos sustratos.
Para establecer una comprensión mecanicista de la vía radical.

Principales métodos:

Catalización doble fotorredóxido y níquel.
Acoplamiento de ésteres β-ceto/amidas con éteres sililenoles/alilosilanos.
Estudios mecánicos que incluyen EPR, DFT y captura de radicales.

Principales resultados:

Síntesis enantioselectiva eficiente de productos de acoplamiento con estereocentros cuaternarios.
Amplio grupo funcional y tolerancia al sustrato.
Confirmación de un mecanismo radical que incluye tautomerismo de valencia.

Conclusiones:

El método desarrollado proporciona una herramienta poderosa para la síntesis asimétrica.
Conocimientos mecanicistas sobre el tautomerismo de valencia en la catálisis.
Potencial para inspirar nuevas transformaciones catalíticas y marcos de reacción.

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