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Preparation of Contiguous Bisaziridines for Regioselective Ring-Opening Reactions

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Diseño racional de un catalizador de enlace de calcógeno de organotelurio para la activación de la azetidina

Fei Jiang¹, Lian-Zheng Zuo¹, Hao-Wen Zhao¹

¹Department of Chemistry and Shenzhen Grubbs Institute, Southern University of Science and Technology, Shenzhen, 518055, China.

Angewandte Chemie (International ed. in English)

|September 2, 2025

Resumen

Este estudio introduce nuevos catalizadores de bis-telluronio para el enlace de calcógeno, lo que permite la primera cicloadición [4+2] de azetidinas con alquenos/alquinas no activados. Estos catalizadores de organotelurio producen eficientemente las estructuras de piperidina y tetrahidropiridina.

Área de la Ciencia:

Química orgánica
Catálisis
Química supramolecular

Sus antecedentes:

La catálisis de enlace de calcógeno, particularmente utilizando telurio, se ha enfrentado a limitaciones debido a la escasa diversidad y actividad del catalizador.
Los catalizadores existentes a base de telurio se utilizan principalmente en reacciones de referencia, lo que restringe las aplicaciones más amplias.

Objetivo del estudio:

Desarrollar nuevos catalizadores de bis-telluronio para aplicaciones mejoradas de enlace de calcógeno.
Para lograr la primera reacción catalítica de cicloadición [4+2] utilizando donantes de enlace de calógeno con azetidinas y alquenos o alquinas cíclicos/acíclicos no activados.
Para sintetizar la piperidina y sus derivados tetrahidropiridina.

Principales métodos:

Diseño y síntesis racionales de los compuestos de bis-teluronio.
Catalización de las reacciones de cicloadición [4+2] entre las azetidinas y varios alquenos/alquinas.
Estudios mecanicistas que incluyen investigaciones experimentales y cálculos de la teoría funcional de la densidad (DFT).

Principales resultados:

Aplicación exitosa de catalizadores de bis-teluronio diseñados para promover reacciones de cicloadición [4+2].
Demostración de una excelente tolerancia del grupo funcional y rendimientos de moderados a buenos para los productos de piperidina y tetrahidropiridina.
Identificación de un nuevo mecanismo de activación de bidentato que involucra la interacción Te-O, respaldado por experimentos mecanicistas y análisis DFT.

Conclusiones:

Los catalizadores de organotelurio desarrollados exhiben una alta actividad, atribuida a los sustituyentes aromáticos con deficiencia de electrones.
Este trabajo amplía el alcance de la catálisis de enlace de calógeno para incluir reacciones de cicloadición desafiantes.
Se ha propuesto un nuevo modo de activación catalítica a través de la interacción Te-O, avanzando en la comprensión de la catálisis mediada por telurio.

Palabras clave:

Azetidina y sus derivados Catalizador de la dication del bis-telluronio Catalización de enlaces de calcógeno [4+2] Adición cíclica

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