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Efficient Synthesis of Polyfunctionalized Benzenes in Water via Persulfate-promoted Benzannulation of α,β-Unsaturated Compounds and Alkynes
Published on: December 16, 2019
Benzeno bajo alta presión: una historia de cristales moleculares que se transforman en redes saturadas, con una
Xiao-Dong Wen1, Roald Hoffmann, N W Ashcroft
1Baker Laboratory, Department of Chemistry and Chemical Biology, Clark Hall, Cornell University, Ithaca, New York 14853, USA.
Journal of the American Chemical Society
|April 29, 2011
Resumen
La alta presión transforma el benceno en polímeros, pero las fases moleculares persisten de manera metastable. Un estado de benceno metálico puede existir entre 180-200 GPa, con barreras de polimerización que influyen en las transiciones.
Área de la Ciencia:
- Química teórica es la química teórica.
- Ciencia de los materiales Ciencia de los materiales.
- Física de la materia condensada Física de la materia condensada
Sus antecedentes:
- El benceno exhibe diversas fases moleculares bajo diferentes presiones.
- Comprender el comportamiento de alta presión es crucial para el diseño de materiales.
Objetivo del estudio:
- Investigar las transformaciones estructurales del benceno hasta 300 GPa.
- Identificar los posibles estados metálicos y las vías de polimerización.
Principales métodos:
- Cálculos teóricos de la estabilidad de fase del benceno.
- Comparaciones de entalpia entre las fases molecular y polimérica.
- Análisis de las barreras cinéticas para el reordenamiento molecular.
Principales resultados:
- Se han observado transiciones de fase conocidas por debajo de 20 GPa.
- Se identificó un polímero unidimensional estable por encima de 50 GPa.
- Se encontró que la fase molecular III (P2(1)/c) es metastable hasta ~200 GPa.
- Predijo un potencial estado de benceno molecular metálico (180-200 GPa).
- Predijo nuevos dímeros de benceno, lo que indica los pasos de polimerización.
Conclusiones:
- El benceno se transforma en polímeros saturados a altas presiones.
- Existen fases moleculares metastables y estados metálicos potenciales.
- Las barreras cinéticas influyen en la polimerización inducida por presión.
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