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Práctica alquinilación conjugada asimétrica de los aceptores derivados del ácido de Meldrum: acceso a los ácidos

Sheng Cui¹, Shawn D Walker, Jacqueline C S Woo

¹Department of Chemical Process Research and Development, Amgen Inc., One Amgen Center Drive, Thousand Oaks, California 91320, USA. scui@amgen.com

Journal of the American Chemical Society

|December 22, 2009

Resumen

Este estudio presenta un método práctico para la alquinilación conjugada asimétrica utilizando cinchonidina como mediador quiral. El proceso produce eficientemente ácidos beta-alquinilo quirales con amplio alcance y escalabilidad.

Área de la Ciencia:

Química orgánica es la química orgánica.
Síntesis asimétrica de síntesis.
La catálisis de la catálisis.

Sus antecedentes:

La adición conjugada enantioselectiva de nucleófilos alquiniles es una transformación sintética desafiante.
El desarrollo de métodos prácticos y escalables para acceder a los bloques de construcción quirales es crucial en la síntesis orgánica.

Objetivo del estudio:

Desarrollar un método de alquilación de conjugados asimétricos altamente práctico.
Proporcionar acceso a valiosos ácidos quirales beta-alquinilo utilizando catalizadores quirales fácilmente disponibles.

Principales métodos:

La alquinilación conjugada asimétrica de los aceptores derivados del ácido de Meldrum.
Utilizando la cinchonidina como un mediador quiral rentable.
Optimización de las condiciones de reacción para un amplio alcance y tolerancia de grupo funcional.

Principales resultados:

Logró una alquinilación conjugada asimétrica muy práctica.
Demostrado amplio alcance de sustrato y excelente compatibilidad de grupo funcional.
Proporcionó un acceso escalable a los ácidos beta-alquinilo quirales.

Conclusiones:

El método desarrollado ofrece una ruta práctica y escalable a los ácidos beta-alquinilo quirales.
La cinconidina es un mediador quiral efectivo y asequible para esta transformación.
Esta metodología amplía el conjunto de herramientas para la síntesis enantioselectiva.

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