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Transferencia intramolecular de protones en estado excitado en o-hidroxibiarilos: una nueva ruta hacia los compuestos
1Department of Chemistry, Box 3065, University of Victoria, Victoria, British Columbia, Canada V8W 3V6.
Journal of the American Chemical Society
|January 30, 2003
Resumen
La transferencia intramolecular de protones en estado excitado (ESIPT) en los naftilfenoles forma eficientemente dihidrobenzoxantenos. Esta reacción proporciona una ruta sintética limpia y de alto rendimiento a valiosos compuestos de benzoxanteno.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La fotoquímica es la fotoquímica.
- Química sintética de la química sintética.
Sus antecedentes:
- La transferencia intramolecular de protones en estado excitado (ESIPT) es un proceso fotoquímico crucial.
- Los benzoxantenos y los dihidrobenzoxantenos son importantes compuestos heterocíclicos con diversas aplicaciones.
Objetivo del estudio:
- Para investigar la reacción de ESIPT en los sistemas de o-(1-naftil) fenol y 1-(1'-naftil)-2-naftol.
- Para establecer una nueva ruta sintética para los dihidrobenzoxantenos utilizando ESIPT.
Principales métodos:
- Estudió ESIPT en derivados de naftilfenol (compuestos 3 y 4).
- Utilizado etiquetado de deuterio para identificar las vías de reacción.
- Caracterizó la formación de productos de dihidrobenzoxanteno (compuestos 5 y 7).
Principales resultados:
- ESIPT eficiente observado desde el fenol OH hasta el 7'-carbono del anillo naftílico.
- Se logró una formación eficiente (rendimiento cuántico 0.1-0.2) de dihidrobenzoxantenos a través de intermediarios de metido de quinona.
- Se ha detectado una vía ESIPT relacionada en la posición 2'-aromática.
Conclusiones:
- La reacción ESIPT descrita ofrece un método limpio, eficiente y de alto rendimiento para sintetizar benzoxantenos y dihidrobenzoxantenos.
- El etiquetado de deuterio confirmó vías alternativas de ESIPT en estos sistemas.
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