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Hidroaminación intermolecular altamente enantioselectiva de los ésteres de allenilo catalizados por fosfinothioureas

Yuan-Qing Fang¹, Pamela M Tadross, Eric N Jacobsen

¹Department of Chemistry and Chemical Biology, Harvard University , Cambridge, Massachusetts 02138, United States.

Journal of the American Chemical Society

|December 16, 2014

Resumen

Los nuevos catalizadores bifuncionales de fosfinothiurea permiten una síntesis altamente selectiva de ésteres de aminoácidos insaturados a partir de ésteres de allenilo y propargilo. Este sistema catalítico logra una excelente regionalidad y enantioselectividad para productos químicos valiosos.

Área de la Ciencia:

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

Sus antecedentes:

El desarrollo de sistemas catalíticos eficientes para la síntesis de aminoácidos es crucial.
Los catalizadores bifuncionales ofrecen una reactividad y selectividad únicas a través de efectos cooperativos.

Objetivo del estudio:

Desarrollar nuevos catalizadores de fosfinothiurea para las reacciones de γ-hidroaminación.
Para lograr una alta regioselectividad y enantioselectividad en la síntesis de ésteres de ácido γ-amino α,β-insaturados.

Principales métodos:

Se utilizaron catalizadores bifuncionales de fosfinothiourea.
Se emplean nucleófilos de N-metoxicarbamato con ésteres de allenilo y propargilo.
Mecanismos de reacción investigados, incluida la isomerización y la adición conjugada.

Principales resultados:

Se logró una γ-hidroaminación altamente regioselectiva y enantioselectiva de los ésteres de allenilo y propargilo.
Se ha demostrado la isomerización controlada por catalizador de los ésteres de propargilo a ésteres de allenilo.
Se identificó un mecanismo de adición conjugado cooperativo responsable de una alta enantioselectividad.

Conclusiones:

Los catalizadores bifuncionales de fosfinothiurea son efectivos para la síntesis de valiosos derivados de aminoácidos.
El sistema catalítico desarrollado ofrece un método preciso para la síntesis asimétrica.
Comprender el mecanismo de reacción proporciona ideas para el diseño de futuros catalizadores.

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