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Reacciones de radicales derivados del boro con los nucleófilos
Lauren E Longobardi1, Pavel Zatsepin1, Roman Korol1
1Department of Chemistry, University of Toronto , 80 St. George Street, Toronto, Ontario M5S 3H6, Canada.
Journal of the American Chemical Society
|December 28, 2016
Resumen
Los radicales borocíclicos derivados de la fenantrenediona y la pirenediona reaccionan con varios nucleófilos, formando diversos zwitteriones y sales. Los cálculos de la Teoría Funcional de Densidad (DFT) aclaran los mecanismos de reacción de estos compuestos de organoboron.
Área de la Ciencia:
- Química organometálica
- Química del boro
- La Química Radical
Sus antecedentes:
- Los radicales borocíclicos son intermediarios versátiles en la síntesis orgánica.
- Comprender su reactividad con los nucleófilos es crucial para desarrollar nuevas metodologías sintéticas.
Objetivo del estudio:
- Investigar las reacciones de los radicales borocíclicos derivados de fenantrenediona y pirenediona con varios nucleófilos.
- Caracterizar los productos resultantes y dilucidar los mecanismos de reacción mediante cálculos de DFT.
Principales métodos:
- Reacción de radicales borocíclicos con fosfinas, carbenos N-heterocíclicos y otros nucleófilos.
- Caracterización completa de los productos mediante técnicas espectroscópicas y analíticas.
- Cálculos de la teoría funcional de la densidad (DFT) para estudiar las vías de reacción.
Principales resultados:
- La reacción del radical borocíclico 1 con P ((t-Bu) 3 produjo un zwitterion y una sal.
- La reacción con PPh3 produjo zwitteriones regioisoméricos y un éster borónico.
- Las reacciones con fosfinas secundarias, carbenos N-heterocíclicos, quinuclidina y DMAP proporcionaron varios productos zwitteriónicos y sales.
Conclusiones:
- El estudio demuestra la diversa reactividad de los radicales borocíclicos derivados de fenantrenediona y pirenediona con los nucleófilos.
- La formación de zwitteriones, sales y ésteres borónicos pone de relieve las vías de reacción complejas.
- Los cálculos DFT proporcionan información sobre los aspectos mecanicistas de estas transformaciones.
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