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Updated: Oct 18, 2025

Chemoselective Preparation of 1-Iodoalkynes, 1,2-Diiodoalkenes, and 1,1,2-Triiodoalkenes Based on the Oxidative Iodination of Terminal Alkynes

Chemoselective Preparation of 1-Iodoalkynes, 1,2-Diiodoalkenes, and 1,1,2-Triiodoalkenes Based on the Oxidative Iodination of Terminal Alkynes

Published on: September 12, 2018

Mecanismo de la hidroalquilación selectiva de las alquinas terminales

Mitchell T Lee¹, Gojko Lalic¹

¹Department of Chemistry, University of Washington, Seattle, Washington 98195, United States.

Journal of the American Chemical Society

|September 30, 2021

Resumen

Este estudio revela un nuevo mecanismo para la hidroalquilación selectiva Z catalizada por plata de los alquinos, cambiando de una vía radical a una que involucra la formación de boronato y los desplazamientos de metalato, lo que explica la alta selectividad Z.

Área de la Ciencia:

Química orgánica
Catálisis
Mecanismos de reacción

Sus antecedentes:

Mecanismos establecidos para la hidroalquilación Z-selectiva de alquinos.
Exploración de las vías de carbometalización radical.

Objetivo del estudio:

Investigar el mecanismo de la hidroalquilación selectiva Z catalizada por plata de las alquinas terminales.
Determinar los factores responsables de la alta selectividad Z.
Identificar el paso limitador de velocidad del ciclo catalítico.

Principales métodos:

Estudio mecanicista detallado.
Los experimentos estequiométricos.
Las mediciones cinéticas, los experimentos de efecto de isótopos cinéticos (KIE) y los experimentos de competencia.

Principales resultados:

La evidencia experimental refutó el mecanismo radical propuesto.
Se propuso un nuevo mecanismo que implica la formación de boronato y un desplazamiento de 1,2-metalato.
Se identificó el papel del catalizador de plata en la protodeboración.
Se determinó el paso limitante de la rotación y el estado de reposo del catalizador.

Conclusiones:

El nuevo mecanismo racionaliza la excelente selectividad Z observada.
Los hallazgos proporcionan información para el desarrollo de transformaciones alquinos relacionadas.
La comprensión del ciclo catalítico ayuda al diseño futuro del catalizador.

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