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Formación de heterociclos medianos y grandes a través de la hidroaminación de Allene con un catalizador de Rh

Kelton G Forson¹, Benjamin O Bohman¹, Coriantumr Z Wayment¹

¹Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, United States.

Journal of the American Chemical Society

|December 29, 2021

Resumen

Un nuevo complejo bimetálico de rodio facilita la hidroaminación alénica intramolecular, sintetizando eficientemente los heterociclos N. Este descubrimiento ofrece una nueva vía para crear diversos compuestos macrocíclicos.

Área de la Ciencia:

Química organometálica
Catálisis
Química orgánica sintética

Sus antecedentes:

La hidroaminación intramolecular es una reacción clave para sintetizar heterociclos que contienen nitrógeno.
El desarrollo de catalizadores eficientes para la macrociclización sigue siendo un desafío importante en la síntesis orgánica.

Objetivo del estudio:

Síntesis y caracterización de un nuevo complejo bimetálico de rodio derivado del 2-fosfinoimidazol.
Investigar la actividad catalítica de este complejo en las reacciones de hidroaminación alénica intramolecular.
Explorar la formación de varios heterociclos N, incluidos los macrociclos.

Principales métodos:

Síntesis de un complejo bimetálico de rodio con un ligando de 2-fosfinoimidazol.
Aplicación del complejo bimetálico como catalizador en la hidroaminación alénica intramolecular.
El alcance del sustrato varía para demostrar la formación de diversos heterociclos y macrociclos N.
Estudios mecánicos en los que se incluyen los intermediarios Rh-hidruro y la formación de enlaces C-N.

Principales resultados:

El complejo bimetálico Rh (II) cataliza efectivamente la hidroaminación alénica intramolecular, produciendo heterociclos de 7 a 10 miembros en altos rendimientos.
Los complejos monometálicos de rodio no mostraron formación de productos en condiciones similares.
Se demostró un amplio alcance de sustrato, lo que permite la síntesis de varios heterociclos N.
Se lograron con éxito macrociclaciones formando N-heterociclos de 11 a 15 miembros.

Conclusiones:

El complejo bimetálico derivado del 2-fosfinoimidazol es un catalizador altamente eficaz para la hidroaminación intramolecular de alenos.
La naturaleza bimetálica única del catalizador es crucial para su mayor reactividad en comparación con las contrapartes monometálicas.
Esta metodología proporciona una nueva ruta poderosa para la síntesis de diversos heterociclos y macrociclos N.

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