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La bromolactonización enantioselectiva y desimetrizante de las alquinas

Michael Wilking¹, Christian Mück-Lichtenfeld, Constantin G Daniliuc

¹Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster , Corrensstrasse 40, 48149 Münster, Germany.

Journal of the American Chemical Society

|May 18, 2013

Resumen

Este estudio demuestra la bromolactonización asimétrica de las alquinas utilizando una estrategia de desimetrización. Un catalizador fácilmente disponible y la N-bromosuccinimida (NBS) producen eficientemente bloques de construcción valiosos de bromoenol lactona con una alta enantioselectividad.

Área de la Ciencia:

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

Sus antecedentes:

La funcionalización de las alquinas es crucial en la síntesis orgánica.
El desarrollo de métodos enantioselectivos para crear moléculas complejas es un desafío clave.
Las lactonas de bromoenol son versátiles intermediarios sintéticos.

Objetivo del estudio:

Para desarrollar una bromolactonización asimétrica de las alquinas.
Para utilizar un enfoque de desimetrización para la ciclización enantioselectiva.
Para generar bloques de construcción valiosos de bromoenol lactona.

Principales métodos:

Empleando una estrategia de desimetrización para la ciclización de alquinos.
Utilizando el catalizador comercialmente disponible (DHQD) 2PHAL.
El uso de N-bromosuccinimida (NBS) como una fuente de bromo barata.

Principales resultados:

Se obtienen altos rendimientos de lactonas de bromoenol.
Se obtiene una alta enantioselectividad en los productos de ciclización.
Productos sintetizados que contienen un alqueno tetrasubstituido y un estereocentro cuaternario.

Conclusiones:

La bromolactonización asimétrica de los alquinos es factible a través de la desimetrización.
El catalizador (DHQD) 2PHAL y el NBS proporcionan un método eficiente.
Las bromoenol lactonas resultantes son valiosos precursores para futuras transformaciones sintéticas.

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