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A Simple and Efficient Protocol for the Catalytic Insertion Polymerization of Functional Norbornenes
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Alquilación y arilación Meta-C-H habilitadas por ligandos utilizando un norborneno modificado
Peng-Xiang Shen1, Xiao-Chen Wang1, Peng Wang1
1Department of Chemistry, The Scripps Research Institute , 10550 North Torrey Pines Road, La Jolla, California 92037, United States.
Journal of the American Chemical Society
|August 28, 2015
Resumen
Un nuevo mediador transitorio, 2-carbomethoxynorbornene, mejora la alquilación C-H catalizada por paladio y la arilación de amidas. Un ligando de quinolina personalizado también es clave para esta eficiente transformación sintética.
Área de la Ciencia:
- Química orgánica
- Catálisis
Sus antecedentes:
- La funcionalización C-H catalizada por el paladio es una herramienta poderosa en la síntesis orgánica.
- El desarrollo de métodos eficientes para la funcionalización meta-C ((sp2) -H de las amidas sigue siendo un desafío.
Objetivo del estudio:
- Identificar mediadores transitorios efectivos para la alquilación y arilación de las amidas por meta-C ((sp2) -H catalizadas por el paladio.
- Desarrollar un sistema catalítico robusto para socios de acoplamiento previamente incompatibles.
Principales métodos:
- Utilizando el 2-carbomethoxynorbornene como mediador transitorio.
- El uso de un ligando de quinolina hecho a medida en reacciones catalizadas por Pd (II).
- Selección de varios yoduros de alquilo y arilo para su acoplamiento con amidas.
Principales resultados:
- El 2-Carbomethoxynorbornene demostró un rendimiento superior como mediador transitorio.
- El sistema catalítico promovió con éxito la alquilación de meta-C ((sp2) -H con diversos yoduros de alquilo.
- La reacción permitió la arilación utilizando yoduros de arilo que antes eran incompatibles con dichas transformaciones.
- El ligando de quinolina personalizado fue esencial para lograr una alta eficiencia y selectividad.
Conclusiones:
- El 2-carbomethoxynorbornene es un mediador transitorio muy eficaz para la funcionalización Pd- catalizada de meta-C(sp2)-H de las amidas.
- La metodología desarrollada amplía el alcance de la alquilación y arilación de C-H, incluyendo sustratos difíciles.
- La combinación del mediador y el ligando especializado ofrece un valioso avance en la química orgánica sintética.
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