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A Protocol for Safe Lithiation Reactions Using Organolithium Reagents
Published on: November 12, 2016
Un modelo derivado de DFT predice la estabilidad de configuración dependiente de la disolución de los compuestos de
Peter Brandt1, Fredrik Haeffner
1Department of Structural Chemistry, Biovitrum AB, 112 76 Stockholm, Sweden.
Journal of the American Chemical Society
|January 8, 2003
Resumen
La disolución afecta la estabilidad del organolitio: la disolución de THF dificulta la racemicidad en monómeros pero la acelera en dímeros, alineándose con los hallazgos experimentales para los compuestos quirales de alfa-tioallilitio.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Química computacional es la química computacional.
Sus antecedentes:
- Los compuestos de organolitio son cruciales en la síntesis orgánica.
- Su estabilidad de configuración está influenciada por la agregación y la solvación.
- Los modelos anteriores sugieren que estos factores son críticos.
Objetivo del estudio:
- Para evaluar un modelo que relaciona la agregación/solución con la estabilidad de la configuración del organolitio.
- Investigar el papel de la solución de THF en la racemización de los monómeros y dímeros quirales de alfa-tioallilitio.
Principales métodos:
- Cálculos de la teoría funcional de la densidad (DFT) utilizando el conjunto base B3LYP/6-31+G*.
- Modelado teórico del alfa-tioallitio quiral monomérico y dimérico en THF.
Principales resultados:
- La solución de THF impide la racemización para el monómero quiral alfa-tioallilitio.
- La dimerización del compuesto acelera el proceso de inversión.
- Los resultados son consistentes con los datos experimentales.
Conclusiones:
- La agregación y la solución afectan significativamente la estabilidad de la configuración del organolitio.
- El desarrollo futuro de organolitio debe tener como objetivo minimizar la agregación y optimizar la solución en estado de transición.
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