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Síntesis, estructura y reacción de los 1-alquinil ((arila) -lambda3-bromanos

Masahito Ochiai¹, Yoshio Nishi, Satoru Goto

¹Faculty of Pharmaceutical Sciences, University of Tokushima, 1-78 Shomachi, Tokushima 770-8505, Japan. mochiai@ph.tokushima-u.ac.jp

Journal of the American Chemical Society

|December 11, 2003

Resumen

Se sintetizaron y caracterizaron nuevos 1-alquinil ((arila) -lambda3-bromanos hipervalentes. Estos compuestos actúan como aceptores de Michael con deficiencia de electrones, sometidos a reorganizaciones en tándem de Michael-carbeno para producir sulfonatos de alquinyl.

Área de la Ciencia:

Química de las organobrominas.
Compuestos hipervalentes de yodo y bromo.
Química orgánica sintética y orgánica.

Sus antecedentes:

Los compuestos de bromo hipervalentes son versátiles intermediarios sintéticos.
Los sustituyentes de alquinilo introducen propiedades electrónicas únicas.
La comprensión de la unión hipervalente es crucial para la nueva reactividad.

Objetivo del estudio:

Informar sobre la primera síntesis y caracterización de los hipervalentes 1-alquinil (arilo) -lambda3-bromanos.
Para investigar la reactividad de estos nuevos compuestos de bromo hipervalentes.
Para explorar su potencial como aceptores de Michael con déficit de electrones.

Principales métodos:

Reacciones de intercambio de ligando catalizadas por el trifluoruro de boro (BF3).
Síntesis mediante el uso de estananos de alquinyl ((trimethyl).
Caracterización por espectroscopia de RMN 13C y difracción de rayos X de un solo cristal.

Principales resultados:

Síntesis exitosa de 1-alquinil ((arila) -lambda3-bromanos en buenos rendimientos.
Síntesis selectiva de silylethynyl-lambda3-bromano. también conocido como silylethynyl-lambda3-bromane.
Elucidación estructural del tert-butiletininilbromano a través de la cristalografía de rayos X.
Demostración del comportamiento del aceptador de Michael y el reordenamiento en tándem de Michael-carbeno.

Conclusiones:

Los hipervalentes 1-alquinil (arilo) -lambda3-bromano son compuestos accesibles y estables.
Estos compuestos exhiben una reactividad única como aceptores de Michael con déficit de electrones.
Las reacciones en tándem proporcionan una vía para nuevos derivados del sulfonato de alquinyl.

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