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Borilación deshidrogenativa catalítica de alquinas terminales por un complejo de pinzas SiNN de iridio

Chun-I Lee¹, Jia Zhou, Oleg V Ozerov

¹Department of Chemistry, Texas A&M University, 3255 TAMU, College Station, Texas 77842, United States.

Journal of the American Chemical Society

|February 5, 2013

Resumen

Ahora es posible la borilación deshidrogenativa catalítica quimioselectiva de las alquinas terminales. Un nuevo catalizador de iridio con un ligando de pinza SiNN único permite una síntesis eficiente de alquilboronatos a partir de enlaces C-H.

Área de la Ciencia:

Química organometálica Química orgánica de los metales.
La catálisis de la catálisis.
Química orgánica sintética y orgánica.

Sus antecedentes:

Los enlaces carbono-boro son intermediarios cruciales en la síntesis orgánica.
La borilación deshidrogenativa catalítica de enlaces C-H es un método sintético muy atractivo.
La borilación de los enlaces C(sp) -H de las alquinas terminales es un reto debido a la hidroboración competitiva.

Objetivo del estudio:

Desarrollar un catalizador quimioselectivo para la borilación C-H de las alquinas terminales.
Para sintetizar alquilboronatos de manera eficiente bajo condiciones suaves.

Principales métodos:

Desarrollo de un nuevo catalizador de iridio con un ligando de pinza SiNN.
La borilación deshidrogenativa catalítica de alquinas terminales mediante el uso de dialcoxiboranos.
Caracterización de los productos de alquilboronato resultantes.

Principales resultados:

El nuevo catalizador de iridio demuestra una estricta quimioselectividad para la borilación C-H sobre la hidroboración.
Una variedad de alquinas terminales se convirtieron en alquinilboronatos (RCC-Bpin) de alto rendimiento y pureza.
La reacción se desarrolla rápidamente a temperatura ambiente.

Conclusiones:

Un nuevo catalizador de iridio con un ligando de pinza SiNN único permite una borilación C-H eficiente y quimioselectiva de alquinas terminales.
Este método proporciona una valiosa ruta hacia los alquilboronatos, versátiles intermediarios sintéticos.
El catalizador desarrollado supera las limitaciones de los métodos anteriores para la borilación de alquinos.

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