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Investigación del alcance y la geoquímica de las cicloadiciones de alquinilboronato con sydnones

Duncan L Browne¹, Jérôme F Vivat, Andrew Plant

¹Department of Chemistry, University of Sheffield, Sheffield S3 7HF, United Kingdom.

Journal of the American Chemical Society

|May 20, 2009

Resumen

Un nuevo método sintetiza diversos ésteres borónicos de pirazol utilizando alquilboronatos y sydnones. Los métodos de la Teoría Funcional de Densidad (DFT) exploraron la divergencia regioquímica en estas reacciones de cicloadición.

Área de la Ciencia:

Química orgánica es la química orgánica.
Química sintética de la química sintética.
Química Medicinal La Química Medicinal es un campo de estudio de la química medicinal.

Sus antecedentes:

Los ésteres borónicos del pirazol son valiosos intermediarios sintéticos.
La síntesis eficiente y regioselectiva de pirazoles sustituidos es crucial.

Objetivo del estudio:

Desarrollar un método regioselectivo para la síntesis de diversos ésteres borónicos del pirazol.
Investigar los orígenes mecanicistas de la divergencia regioquímica en las cicloadiciones de alquinylboronato-sydnona.

Principales métodos:

Reacción de cicloadición entre los alquinilboronatos y las sydnones.
Cálculos de la Teoría Funcional de Densidad (DFT) para estudiar los mecanismos de reacción.

Principales resultados:

Se sintetizó una amplia gama de di-, tri- y tetrasubstituidos ésteres borónicos de pirazol.
El análisis de DFT aclaró los factores que rigen la selectividad y la divergencia regionales.

Conclusiones:

La cicloadición alquinilboronato-sydnona es una vía versátil y regioselectiva para los ésteres borónicos del pirazol.
Comprender el mecanismo de reacción ayuda a controlar los resultados regioquímicos para la síntesis dirigida.

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