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Los α-aminoaldehídos como aldehídos quirales fácilmente disponibles para la hidroacilación de alquinos catalizados

Joel F Hooper¹, Sangwon Seo¹, Fiona R Truscott¹

¹Department of Chemistry, Chemistry Research Laboratory, University of Oxford , Mansfield Road, Oxford, OX1 3TA, U.K.

Journal of the American Chemical Society

|January 16, 2016

Resumen

Las reacciones de hidroacilación de alquinos catalizados por Rh utilizan eficientemente los aldehídos α-amino con un grupo protector metilthiometilo (MTM). Este método ofrece condiciones suaves, un amplio alcance de sustrato y una alta estereospecificidad para sintetizar aminoenonas valiosas.

Área de la Ciencia:

Química orgánica
Catálisis
Metodología sintética

Sus antecedentes:

Los α-aminoaldehídos son bloques de construcción versátiles en la síntesis orgánica.
Las estrategias de protección del grupo son cruciales para controlar la reactividad en moléculas complejas.
Las reacciones catalizadas por el rodio ofrecen herramientas poderosas para la formación de enlaces carbono-carbono.

Objetivo del estudio:

Desarrollar una hidroacilación catalizada por Rh eficiente de los α-amino aldehídos.
Explorar el alcance y las limitaciones de este nuevo método sintético.
Demostrar la utilidad de los productos resultantes en la síntesis de productos naturales.

Principales métodos:

Utilizando aldehídos α-amino disponibles con un grupo protector metiltiometilo (MTM) unido al nitrógeno.
Utilizando hidroacilación de alquina catalizada por Rh en condiciones suaves.
Uso de un ligando de bisfosfina de ángulo de mordida pequeño para mejorar la reactividad y la selectividad.

Principales resultados:

Hidroacilación exitosa de diversos aldehídos α-amino, incluidos los derivados de varios aminoácidos y ácido feniláctico.
Se ha demostrado una buena tolerancia funcional del grupo y una alta estereospecificidad.
Productos de α-aminoenona sintetizados con potencial para otras transformaciones.

Conclusiones:

La hidroacilación catalizada por Rh desarrollada es un método eficiente para sintetizar las enonas α-amino.
El grupo protector MTM facilita la reacción en condiciones suaves y estereospecíficas.
La utilidad sintética se destaca por una breve síntesis enantioselectiva de la esfingosina.

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