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El escurridizo éter imino cíclico de siete miembros Tetrahydrooxazepine
Bart Verbraeken1, Jan Hullaert2, Joachim van Guyse1
1Supramolecular Chemistry group, Centre of Macromolecular Chemistry (CMaC), Department of Organic and Macromolecular Chemistry , Ghent University , Krijgslaan 281 S4 , 9000 Ghent , Belgium.
Journal of the American Chemical Society
|December 4, 2018
Resumen
Este estudio informa de la primera síntesis de iminoéteres cíclicos de siete miembros, corrigiendo errores de identificación anteriores. La investigación también compara su reactividad de polimerización, revelando un efecto significativo en el tamaño del anillo en la polimerización de apertura de anillo catiónico (CROP).
Área de la Ciencia:
- Química orgánica
- Química de los polímeros
- Química Heterocíclica
Sus antecedentes:
- Los iminoéteres cíclicos son valiosos en catálisis, productos farmacéuticos y polimerización.
- Mientras que los anillos de cinco y seis miembros (oxazolinas, oxazinas) están bien estudiados, las contrapartes de siete miembros permanecen inexploradas.
- Los informes anteriores de iminoéteres cíclicos de siete miembros probablemente fueron identificados erróneamente como isómeros de pirrolidina N-acilada.
Objetivo del estudio:
- Síntesis y caracterización de éteres iminos cíclicos de siete miembros.
- Para corregir la asignación estructural de compuestos previamente reportados.
- Investigar el efecto del tamaño del anillo en la reactividad de la polimerización por apertura de anillo catiónico (CROP) de los éteres imino cíclicos.
Principales métodos:
- Síntesis de 2-fenil-4,5,6,7-tetrahidro-1,3-oxazepina.
- Elucidación estructural y reasignación de compuestos relacionados.
- Estudio comparativo de la reactividad de CROP para iminoéteres cíclicos homólogos con diferentes longitudes de puente de metileno.
Principales resultados:
- Síntesis exitosa de un éter imino cíclico de siete miembros, el 2-fenil-4,5,6,7-tetrahidro-1,3-oxazepina.
- Corrección de la literatura anterior, identificando los anillos de siete miembros previamente reportados como isómeros de pirrolidina N-acilados.
- Demostración de un efecto significativo del tamaño del anillo en la reactividad de CROP en una serie homóloga.
Conclusiones:
- La síntesis de iminoéteres cíclicos de siete miembros es ahora posible.
- La identificación estructural precisa es crucial para comprender su química.
- El tamaño del anillo influye profundamente en el comportamiento de polimerización de los éteres imino cíclicos en CROP.
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