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Las distorsiones de indolina y arina y las regioselectividades nucleófilas

Paul H-Y Cheong¹, Robert S Paton, Sarah M Bronner

¹Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, USA.

Journal of the American Chemical Society

|January 12, 2010

Resumen

La teoría funcional de la densidad explica la regioselectividad en las reacciones indolínicas. Las energías de distorsión del estado de transición, no las interacciones orbitales, dictan la formación de productos, guiando la síntesis de productos específicos sustituidos.

Área de la Ciencia:

Química orgánica es la química orgánica.
Química computacional es la química computacional.

Sus antecedentes:

Las indolinas son reactivos intermedios en la síntesis orgánica.
El control de la regioselectividad en las reacciones de indolina es crucial para la síntesis dirigida.

Objetivo del estudio:

Aclarar los factores que rigen la regioselectividad en las adiciones nucleófilas y cicloadiciones a las indolinas.
Para explicar las diferencias observadas en la regioselectividad entre 4,5- y 5,6-indolines.

Principales métodos:

Se emplearon cálculos de la teoría funcional de la densidad (DFT).
Se analizaron las energías de distorsión del estado de transición.
Se evaluaron las interacciones orbitales y electrostáticas.

Principales resultados:

DFT reprodujo con precisión las regioselectividades experimentales para 4,5- y 5,6-indolines.
Las energías de distorsión del estado de transición se identificaron como los principales impulsores de la regioselectividad.
Se predijeron elevadas regioselectividades para 6,7-indolines y se confirmaron experimentalmente.

Conclusiones:

La regioselectividad en las reacciones indolínicas está predominantemente controlada por las energías de distorsión de los estados de transición.
Las interacciones orbitales y electrostáticas juegan un papel menor.
Este modelo de distorsión proporciona un marco para comprender y predecir la regioselectividad en la química aryne.

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