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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
Construcción estereoselectiva de éteres cíclicos utilizando una éterificación en tándem de dos componentes:
P Andrew Evans1, Jian Cui, Santosh J Gharpure
1Department of Chemistry, Indiana University, Bloomington, Indiana 47405, USA. paevans@indiana.edu
Journal of the American Chemical Society
|September 18, 2003
Resumen
Este estudio introduce un nuevo método para sintetizar tetrahidropiranos, componentes cruciales en muchos productos farmacéuticos. El enfoque catalítico ofrece una ruta estereoselectiva para construir éteres cíclicos complejos, mejorando los esfuerzos de descubrimiento de fármacos.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Química Medicinal La Química Medicinal es un campo de estudio de la química medicinal.
- Química sintética de la química sintética.
Sus antecedentes:
- Los éteres cíclicos, en particular los derivados del C-glucósido, son frecuentes en compuestos naturales y sintéticos farmacológicamente significativos.
- La síntesis estereoselectiva de tetrahidropiranos sustituidos es un desafío clave en la química orgánica.
Objetivo del estudio:
- Desarrollar un método estereodivergente para la construcción de tetrahidropiranos cis- y trans-2,6-di- y trisubstituidos.
- Para dilucidar el mecanismo catalítico que involucra el tribromuro de bismuto.
Principales métodos:
- Eterificación intramolecular de los aldehídos delta-trialquilsililoxi y las cetonas.
- Utilizando el tribromuro de bismuto catalítico y los nucleófilos de trialkylsilyl.
- Investigando el papel de los productos de hidrólisis (HBr, BiOBr) en la catálisis.
Principales resultados:
- Síntesis exitosa de tetrahidropiranos cis- y trans-2,6-disubstituidos y trisubstituidos.
- Se ha demostrado una alta estereoselectividad en la construcción de éteres terciarios adyacentes.
- Desarrolló un acoplamiento cruzado secuencial y una eterificación reductiva para la síntesis de tetrahidropirano no adyacente.
Conclusiones:
- El tribromuro de bismuto actúa como catalizador, probablemente a través de sus productos de hidrólisis, para la síntesis estereoselectiva de tetrahidropirano.
- El protocolo desarrollado proporciona una ruta eficiente a valiosos andamios de éter cíclico.
- Este método facilita la síntesis de moléculas complejas con aplicaciones farmacéuticas potenciales.
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