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Azidación-cicloadición asimétrica con catalizadores basados en péptidos de cadena abierta. Una ruta enantioselectiva
David J Guerin1, Scott J Miller
1Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467-3860, USA.
Journal of the American Chemical Society
|March 7, 2002
Resumen
Los investigadores sintetizaron péptidos de histidina sustituidos por beta para mejorar la enantioselectividad del catalizador. Este enfoque mejoró las reacciones asimétricas de azidación, lo que condujo a triazoles y triazolinas ópticamente enriquecidas.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis de la catálisis.
- Síntesis asimétrica de síntesis.
Sus antecedentes:
- Los péptidos que contienen histidina son catalizadores versátiles.
- La rigidificación conformacional no covalente es una estrategia para mejorar el rendimiento del catalizador.
- La enantioselectividad es crucial para la síntesis de moléculas quirales.
Objetivo del estudio:
- Para sintetizar péptidos que contienen histidina sustituidos por beta.
- Para investigar el efecto de la rigidificación conformacional no covalente en la enantioselectividad del catalizador.
- Aplicar los catalizadores desarrollados en síntesis asimétrica.
Principales métodos:
- Síntesis de una familia de péptidos que contienen histidina sustituidos por beta.
- Evaluación de la enantioselectividad del catalizador en la adición conjugada de azida a los derivados de carboxilato alfa, beta insaturados.
- Aplicación en una reacción secuencial asimétrica de azidación/cicloadición.
Principales resultados:
- Se ha demostrado una mejora inequívoca de la enantioselectividad.
- Se ha logrado una aplicación exitosa en una secuencia asimétrica de azidación/cicloadición.
- Síntesis de triazoles y triazolinas ópticamente enriquecidos.
Conclusiones:
- Los péptidos que contienen histidina sustituidos por beta mejoran efectivamente la enantioselectividad a través de la rigidificación conformacional no covalente.
- El sistema catalítico desarrollado es aplicable para la síntesis de triazoles y triazolinas enriquecidos ópticamente.
- Este trabajo proporciona una nueva estrategia para diseñar catalizadores quirales eficientes.
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