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Cobre ((I) - Alquilación asimétrica catalizada de fosfinas secundarias no simétricas

Shuai Zhang¹, Jun-Zhao Xiao¹, Yan-Bo Li¹

¹CAS Key Laboratory of Synthetic Chemistry of Natural Substances, Centre for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China.

Journal of the American Chemical Society

|June 23, 2021

Resumen

Una nueva reacción catalizada por el cobre permite la síntesis de fosfinas quirales utilizando haluros de alquilo. Este método logra altos rendimientos y enantioselectividad, lo que demuestra un amplio alcance de sustrato y utilidad en la síntesis de nuevos ligandos quirales.

Área de la Ciencia:

Química organometálica
Catálisis asimétrica
Química orgánica sintética

Sus antecedentes:

Las fosfinas quirales son ligandos cruciales en la catálisis asimétrica.
Es muy deseable desarrollar métodos eficientes para sintetizar fosfinas enantioméricamente puras.

Objetivo del estudio:

Desarrollar una nueva alquilación asimétrica catalizada por el cobre de las diarilfosfinas.
Para sintetizar una gama de fosfinas P-esterógenas con alto rendimiento y enantioselectividad.

Principales métodos:

Alquilación asimétrica catalizada por el cobre utilizando varios haluros de alquilo (alilo, propargilo, bromuros de bencilo y yoduros de alquilo).
Se utilizaron 11 diferentes diarilfosfinas asimétricas (HPAr1Ar2) como pronucleófilos.
Se han investigado reacciones de alquilación catalítica asimétrica doble y triple.

Principales resultados:

Se ha logrado la síntesis de fosfinas P-esterógenas de alto rendimiento y enantioselectividad.
Se ha demostrado una amplia gama de sustratos para haluros de alquilo electrófilos.
Se obtiene una diastereoselectividad moderada y una enantioselectividad excelente en productos de doble y triple alquilación.
Identificó el complejo Cu (I) - (R,R) -TANIAPHOS como altamente efectivo para la inducción asimétrica.

Conclusiones:

La metodología desarrollada proporciona una ruta eficiente hacia las valiosas fosfinas P-esterógenas.
Las fosfinas sintetizadas sirven como ligandos quirales efectivos para los complejos de cobre.
Este trabajo destaca la utilidad sintética de la nueva reacción de alquilación asimétrica.

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