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Túneles de carbono en la expansión del anillo de noradamantilclorocarbeno
Robert A Moss1, Ronald R Sauers, Robert S Sheridan
1Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, New Brunswick, NJ 08903, USA. moss@rutchem.rutgers.edu
Journal of the American Chemical Society
|August 19, 2004
Resumen
La fotólisis de una clorodiazirina genera un noradamantilclorocarbeno. Este carbeno se reorganiza en cloroadamanteno, potencialmente a través de un túnel cuántico a bajas temperaturas.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La fotoquímica es la fotoquímica.
- La espectroscopia es una técnica de espectroscopia.
Sus antecedentes:
- Los carbenos son intermediarios altamente reactivos.
- Los derivados del adamantano ofrecen propiedades estructurales únicas.
Objetivo del estudio:
- Para investigar la fotoquímica de la 3-(3-noradamantil)-3-clorodiazirina. para el estudio de la fotoquímica de la 3-(3-noradamantil)-3-clorodiazirina. para el estudio de la fotoquímica de la 3-clorodiazirina.
- Para caracterizar el noradamantilclorocarbeno generado y sus reacciones posteriores.
Principales métodos:
- Fotólisis de flash láser para la detección de soluciones.
- Espectroscopia infrarroja (IR) y UV/Vis en matrices criogénicas (N2, Ar) a 9 K.
- Experimentos de atrapamiento en solución.
Principales resultados:
- El noradamantilclorocarbeno fue detectado espectroscópicamente.
- El carbeno se reorganiza en 2-cloro-1-adamanteno a temperaturas ambientales y bajas.
- La tasa de reordenamiento a 9 K fue significativamente más rápida de lo que se predijo teóricamente, lo que sugiere un túnel cuántico.
Conclusiones:
- La fotólisis de la diazirina es una vía viable para el noradamantilclorocarbeno.
- El túnel mecánico cuántico se propone como el mecanismo para el reordenamiento del carbeno a baja temperatura al cloroadamanteno.
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