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Isomerización-hidroboración de alqueno catalizado por cobalto de bis ((imino) piridina: una estrategia para la

Jennifer V Obligacion¹, Paul J Chirik

¹Department of Chemistry, Princeton University , Princeton, New Jersey 08544, United States.

Journal of the American Chemical Society

|December 17, 2013

Resumen

Los catalizadores de cobalto de bis(imino) piridina realizan eficientemente la hidroboración de alquenos utilizando el pinacolborano (HBPin). Un catalizador modificado muestra una alta actividad para sustratos obstaculizados, ofreciendo una nueva ruta para la funcionalización de enlaces C-H.

Área de la Ciencia:

Química organometálica Química orgánica de los metales.
La catálisis es la catálisis.
Síntesis orgánica La síntesis orgánica.

Sus antecedentes:

La hidroboración de alquenos es una transformación orgánica clave.
El desarrollo de catalizadores eficientes y selectivos es crucial para la química sintética.

Objetivo del estudio:

Para investigar los complejos metilo de cobalto bis(imino) piridina como catalizadores para la hidroboración de alqueno.
Para optimizar la estructura del catalizador para mejorar la actividad y la selectividad, especialmente con sustratos estéricamente obstaculizados.

Principales métodos:

Síntesis y caracterización de los complejos metílicos de cobalto bis ((imino) piridina.
Reacciones de hidroboración catalítica utilizando pinacolborano (HBPin) con varios alquenos.
Evaluación de los sustituyentes catalizadores para identificar las estructuras óptimas.

Principales resultados:

Los complejos metílicos de cobalto de bis ((imino) piridina catalizan efectivamente la hidroboración de diversos alquenos.
Un catalizador sustituido por pirrolidinilo demostró una actividad superior para sustratos estéricamente exigentes.
Las reacciones continuaron con una alta selectividad anti-Markovnikov en condiciones suaves (23 °C) en sustratos limpios.
Las olefinas internas se sometieron a adición exclusiva de boro terminal, lo que permitió la funcionalización remota C-H.

Conclusiones:

Los complejos de cobalto bis(imino) piridina modificados son catalizadores muy efectivos para la hidroboración de alquenos.
El sistema catalítico desarrollado ofrece un método versátil y selectivo para la hidroboración y la funcionalización C-H.

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