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Updated: Jan 15, 2026

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis

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Dihidroboración de alquinos mediante catálisis de clúster de níquel formado in situ: reordenamiento de la adición de

Yuyang Su¹, Kaidong Shen², Pingsen Shi³

¹State Key Laboratory of Organometallic Chemistry and Shanghai Hongkong Joint Laboratory in Chemical Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, P. R. China.

Journal of the American Chemical Society

|October 15, 2025

Resumen

Este estudio introduce un sistema catalizado por níquel para la doble hidroboración de alquinas utilizando nanocúmulos formados in situ. Sintetiza eficientemente compuestos estérilmente obstaculizados a través de un nuevo mecanismo de adición de gemas.

Área de la Ciencia:

Catálisis
Química de los nanomateriales
Síntesis orgánica

Sus antecedentes:

La comprensión de los nanocúmulos formados in situ en la catálisis es un desafío.
Los nanocúmulos multimetales exhiben mecanismos catalíticos únicos distintos de los catalizadores moleculares o heterogéneos.

Objetivo del estudio:

Desarrollar un sistema catalítico para la doble hidroboración regioselectiva de alquinas internas no simétricas.
Explorar la actividad catalítica de los nanocúmulos de níquel generados in situ.

Principales métodos:

Reacción catalizada por níquel de las alquinas internas con el pinacolborano (HBpin).
Estudios mecánicos para elucidar la vía catalítica.

Principales resultados:

Síntesis eficiente de alcanos 1,1-diborilo cuaternarios estéricamente congestionados.
Demostración de la activación simultánea de múltiples moléculas de HBpin por nanocúmulos de Ni.
Evidencia de un nuevo mecanismo de adición de gemas (adición de gemas H, H y B, B).

Conclusiones:

Los nanocúmulos de Ni generados in situ permiten una reactividad sin precedentes en la hidroboración doble.
La vía de adición de gemas descubierta difiere fundamentalmente de la hidroboración secuencial.
Las arquitecturas de nanocúmulos polinucleares ofrecen ventajas para nuevas vías catalíticas.

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