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Reducción de policiclos tensados: ¿cuánto esfuerzo puede soportar un anión pireno?
Ivan Aprahamian1, Graham J Bodwell, Jim J Fleming
1Department of Organic Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
Journal of the American Chemical Society
|May 27, 2004
Resumen
La tensión en [n]{2,7) pirenofanos dicta los productos de reducción. Las ataduras más cortas producen dimerización y formación de enlaces sigma, mientras que las ataduras más largas conducen a especies dianiónicas y escisión de disolventes.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Química supramolecular de las moléculas.
Sus antecedentes:
- Los pirenofanos son hidrocarburos aromáticos policíclicos con puentes atados.
- Comprender su reactividad es crucial para diseñar nuevos materiales orgánicos.
Objetivo del estudio:
- Para investigar el efecto de la longitud de la correa en el comportamiento reductor de [n]{\displaystyle [n]{\text{n}}{2,7}}) pirenofanos.
- Para dilucidar las vías de reacción y los productos formados durante la reducción de metales.
Principales métodos:
- Reducción de [n](2,7) pirenofanos (n=7-10) utilizando litio o potasio metálico.
- Análisis de productos de reducción mediante técnicas espectroscópicas.
Principales resultados:
- Las ataduras más cortas ([7]- y [2]metaciclo[2]-) dieron como resultado una dimerización reductora y la formación de enlaces sigma intramoleculares.
- [8](2,7) El pirenofano sólo se sometió a una dimerización reductora.
- Las ataduras más largas ([9]- y [10](2,7) pirenofanos) formaron especies anti-aromáticas dianiónicas, lo que condujo a la escisión del disolvente.
Conclusiones:
- La tensión de la correa es un factor clave que controla las vías de reducción de los pirenofanos.
- Se observaron nuevas vías de reacción, incluida la formación de enlaces sigma y la escisión del disolvente.
- El comportamiento de reducción de los pirenofanos atados más largos se asemeja al del propio pireno.
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