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Spatial Separation of Molecular Conformers and Clusters
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Reacciones de Pummerer asimétricas altamente estereoselectivas que incorporan interacciones S...O no unidas
Yoshimitsu Nagao1, Satoshi Miyamoto, Motoyuki Miyamoto
1Contribution from the Graduate School of Pharmaceutical Sciences, The University of Tokushima, Sho-machi, Tokushima 770-8505, Japan.
Journal of the American Chemical Society
|July 27, 2006
Resumen
Se sintetizaron y caracterizaron nuevos sulfóxidos quirales. Estos compuestos permitieron reacciones de Pummerer altamente estereoselectivas, lo que demuestra la importancia de las interacciones S...O no unidas para la transferencia quiral en la síntesis orgánica.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La estereoquímica es la estereoquímica.
- La cristalografía es una técnica de cristalografía.
Sus antecedentes:
- Los sulfóxidos quirales son importantes intermediarios sintéticos.
- La comprensión de las interacciones no vinculadas es crucial para las reacciones estereoselectivas.
Objetivo del estudio:
- Sintetice y caracterice nuevos sulfóxidos quirales.
- Investigar el papel de las interacciones S...O sin enlaces en las reacciones de Pummerer.
- Desarrollar reacciones de Pummerer altamente diastereoselectivas y enantioselectivas.
Principales métodos:
- Síntesis de sulfóxidos quirales.
- Análisis cristalográfico de rayos X. Análisis cristalográfico de rayos X.
- Espectrometría de masas de ionización por pulverización en frío. espectrometría de masas de ionización por pulverización en frío.
- Reacciones de Pummerer con varias amidas y triflados de sililo.
Principales resultados:
- Se sintetizaron nuevos sulfóxidos quirales (3 y 4) y su estereoquímica confirmada por cristalografía de rayos X.
- Se identificaron interacciones S...O no unidas intramoleculares e intermoleculares en las estructuras y soluciones de sulfóxido.
- Se lograron reacciones de Pummerer altamente diastereoselectivas y enantioselectivas.
- Se encontró que los complejos amida/TMSOTf son esenciales para la activación eficiente y la transferencia quiral estereoselectiva.
Conclusiones:
- Las interacciones S...O sin enlaces juegan un papel clave en el control de la estereoquímica durante las reacciones de Pummerer.
- El método desarrollado ofrece una ruta fácil a compuestos estereodefinidos.
- Las amidas como DMAC y NMP influyen positivamente en la estereoselectividad de la transferencia quiral.
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