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Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones

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Bispalladaciclo catalizado por el ácido y la base de Brønsted promovió la formación de azlactona en tándem asimétrico

Manuel Weber¹, Sascha Jautze, Wolfgang Frey

¹Institut für Organische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany.

Journal of the American Chemical Society

|August 19, 2010

Resumen

Un nuevo sistema catalítico permite la síntesis de derivados de aminoácidos complejos con estereocentros cuaternarios y terciarios adyacentes. Este método produce de manera eficiente compuestos enantioenriquecidos y diastereoméricamente puros a partir de materiales de partida racémicos.

Área de la Ciencia:

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

Sus antecedentes:

Síntesis desafiante de ácidos alfa-amino con estereocentros cuaternarios y terciarios adyacentes.
Necesidad de métodos eficientes para controlar la estereoquímica en la síntesis de moléculas complejas.

Objetivo del estudio:

Desarrollar un sistema catalítico cooperativo para la síntesis enantioselectiva de ácidos alfa-amino enmascarados.
Para crear estereocentros cuaternarios y terciarios adyacentes en una sola reacción.

Principales métodos:

Utilizó una combinación de un catalizador bimetálico blando, un ácido Brønsted duro y una base Brønsted dura.
Empleado racemic N-benzoylated aminoácidos como materiales de partida.

Principales resultados:

Se logró la formación de ácidos alfa-aminoácidos enmascarados altamente enriquecidos con enantio y diastereoméricamente puros.
Generó con éxito estereocentros cuaternarios y terciarios adyacentes en un solo paso.

Conclusiones:

El sistema catalítico cooperativo es eficaz para la síntesis estereoselectiva de derivados de aminoácidos complejos.
Los productos sintetizados sirven como valiosos precursores para los dipeptídeos bicíclicos.

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