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Clorinación directa catalizada por indio de alcoholes utilizando clorodimetilsilano-bencilo como un sistema selectivo
Makoto Yasuda1, Satoshi Yamasaki, Yoshiyuki Onishi
1Department of Molecular Chemistry and Handai Frontier Research Center, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
Journal of the American Chemical Society
|June 10, 2004
Resumen
Un nuevo método catalizado por InCl3 convierte eficientemente los alcoholes en cloruros orgánicos utilizando clorodimetilsilano y bencilo. Esta reacción se produce en condiciones suaves y muestra una alta selectividad para los alcoholes terciarios, incluso con grupos funcionales sensibles al ácido presentes.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis por catálisis.
- Metodología sintética de la metodología sintética.
Sus antecedentes:
- Los métodos tradicionales para la cloración de alcohol a menudo requieren condiciones duras o reactivos específicos.
- El desarrollo de protocolos de cloración suave y selectiva es crucial para la síntesis de moléculas complejas.
Objetivo del estudio:
- Desarrollar un método novedoso, suave y selectivo para convertir los alcoholes en cloruros orgánicos.
- Investigar el papel del bencilo en la influencia de la vía de reacción y la selectividad.
Principales métodos:
- Utilizando el cloruro de indio (InCl3) como catalizador.
- Con el uso de clorodimetilsilano (HSiMe2Cl) como agente clorante.
- Investigando el efecto del bencilo como aditivo en el resultado de la reacción.
Principales resultados:
- Se logró una cloración eficiente de los alcoholes secundarios y terciarios en condiciones suaves.
- Se encontró que la presencia de bencilo era crítica, previniendo la deshidroxihidratación y dirigiendo la reacción hacia la cloración.
- El método demostró una alta selectividad para los alcoholes terciarios en reacciones competitivas con los alcoholes primarios.
- Se toleraron sustratos con grupos funcionales sensibles al ácido.
Conclusiones:
- La reacción catalizada por InCl3 con HSiMe2Cl y bencilo proporciona una ruta efectiva hacia los cloruros orgánicos.
- Se propone que un intermediario de hidrosilano altamente coordinado, formado a partir de bencilo y HSiMe2Cl, sea clave para el éxito de la reacción.
- Esta metodología ofrece una herramienta valiosa para la cloración selectiva en la síntesis orgánica.
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