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Sustitución nucleófila formal altamente diastereo-selectiva de los bromociclopropanetos por la sustitución nucleófila
Bassam K Alnasleh1, William M Sherrill, Marina Rubina
1Department of Chemistry, The University of Kansas, 1251 Wescoe Hall Drive, Lawrence, Kansas 66045-75832, USA.
Journal of the American Chemical Society
|May 6, 2009
Resumen
Este estudio demuestra un nuevo método para sintetizar moléculas complejas utilizando bromociclopropanos. La reacción ofrece un alto control sobre la estereoquímica, lo que permite la creación de valiosos compuestos quirales.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Química sintética de la química sintética.
- Síntesis estereoselectiva de síntesis.
Sus antecedentes:
- Los ciclopropanos son sistemas de anillos tensados con una reactividad única.
- Las reacciones de sustitución nucleófila son fundamentales en la síntesis orgánica.
- El control de la estereoquímica en la funcionalización del ciclopropano sigue siendo un desafío.
Objetivo del estudio:
- Desarrollar una sustitución nucleofílica formal altamente diastereoselectiva de los bromociclopropanos.
- Para investigar el mecanismo que involucra a los intermediarios del ciclopropeno.
- Explorar métodos para controlar la selectividad facial en el paso de adición.
Principales métodos:
- Deshidrohalogenación asistida por base de los bromociclopropanos.
- Adición de nucleófilos basados en oxígeno y nitrógeno a los intermediarios de ciclopropeno.
- Utilizando estéricos y grupos de dirección para controlar la selectividad facial.
- Empleando aminoalcoholes ópticamente activos atados como pronucleófilos.
Principales resultados:
- Se logró una sustitución nucleofílica formal altamente diastereoselectiva.
- Se ha demostrado una alta quimioselectividad para alcóxidos primarios/secundarios y N-nucleófilos.
- Identificó estrategias de grupo estérico y de dirección efectivas para el control de la selectividad facial.
- Sintetizó con éxito compuestos homoquirales bicíclicos utilizando aminoalcoholes quirales.
Conclusiones:
- El método desarrollado proporciona un acceso eficiente a los ciclopropanos funcionalizados con estereoquímica controlada.
- El mecanismo de reacción implica un intermediario de ciclopropeno, que ofrece una plataforma sintética versátil.
- Este enfoque es valioso para la construcción de moléculas quirales complejas, incluidos los sistemas bicíclicos.
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