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La aminación alilica catalizada por el complejo de iridio de los ésteres alilicos
1Department of Chemistry, Graduate School of Integrated Science, Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama 236-0027, Japan. rtakeuch@yokohama-cu.ac.jp
Journal of the American Chemical Society
|September 27, 2001
Resumen
La catálisis del complejo de iridio permite una eficiente aminación alilica de los carbonatos. Los disolventes polares como el etanol son cruciales para los altos rendimientos, ofreciendo una selectividad superior en comparación con los catalizadores de paladio.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- La catálisis es la catálisis.
- Síntesis orgánica La síntesis orgánica.
Sus antecedentes:
- La aminación alilica es una transformación clave en la síntesis orgánica.
- El desarrollo de métodos catalíticos eficientes y selectivos es crucial.
- Los métodos anteriores a menudo carecen de control sobre la regioselectividad y la estereoselectividad.
Objetivo del estudio:
- Para investigar la aminación alilica catalizada por el complejo de iridio de los carbonatos alilicos.
- Explorar la influencia de los disolventes y las condiciones de reacción en la actividad catalítica y la selectividad.
- Establecer una nueva ruta sintética para las aminas alilicas con alta selectividad.
Principales métodos:
- Utilizado complejo de iridio, específicamente [Ir(COD) Cl](2) con P(OPh)(3) como catalizador.
- Investigó el efecto de varios disolventes, con un enfoque en los disolventes polares como el etanol.
- Examinó la reacción con diferentes sustratos de carbonato alílico y varias aminas primarias y secundarias.
Principales resultados:
- Se lograron altos rendimientos y selectividades (hasta el 99%) para las aminas alilicas ramificadas utilizando carbonatos (E) -alilicos.
- Se observó monoalilación selectiva con aminas primarias, lo que impide la dialilación.
- Formación exclusiva de aminas alilicas alfa, alfa-disubstituidas a partir de acetatos de 1,1-disubstituido-2-propenilo.
- Alta selectividad (hasta el 100%) para las aminas alilicas (Z) lineales a partir de carbonatos (Z) alilicos, sin formación de isómero (E).
- Se ha demostrado una selectividad superior en comparación con reacciones similares catalizadas por paladio.
Conclusiones:
- La catálisis del iridio proporciona un método altamente selectivo para la aminación alílica de carbonatos alílicos.
- Los disolventes polares son esenciales para lograr una alta actividad catalítica y rendimientos.
- Este método ofrece una valiosa alternativa para sintetizar diversas aminas alilicas con una selectividad sin precedentes.
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