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Selectividad controlada por isótopos mediante túnel cuántico: migración de hidrógeno versus expansión de anillos en
Ashim Nandi1, Dennis Gerbig2, Peter R Schreiner2
1Department of Chemistry, Ben-Gurion University of the Negev , Beer-Sheva 841051, Israel.
Journal of the American Chemical Society
|June 22, 2017
Resumen
Este estudio introduce la selectividad controlada por isótopos (ICS), un nuevo método para controlar las reacciones químicas. Al alterar los isótopos, los químicos pueden dirigir con precisión las reacciones hacia productos específicos, una primicia para los efectos cinéticos de los isótopos.
Área de la Ciencia:
- Química Cuántica
- Reactividad química
- Efectos de los isótopos
Sus antecedentes:
- La reactividad del carbeno a menudo está influenciada por el túnel mecánico cuántico.
- El control de las vías de reacción basadas en la composición isotópica sigue siendo un desafío.
Objetivo del estudio:
- Demostrar la selectividad controlada por isótopos (ICS) como un nuevo método para controlar la reactividad química.
- Investigar el potencial de las reacciones de carbeno controladas por túnel para ICS.
Principales métodos:
- Utilizó cálculos multidimensionales de túnel de pequeña curvatura (SCT).
- Se analizó la reactividad del ciclopropilmetilcarbeno y su análogo sustituido por deuterio.
Principales resultados:
- Se prevé la formación exclusiva de 1-metoxi-1-vinilciclopropano a partir del 1-metoxiciclopropilmetilcarbeno mediante la migración H.
- Se prevé la formación exclusiva de 1-d3-metilciclobuteno a partir del carbeno sustituido por deuterio mediante la expansión del anillo.
- ICS demostrado mostrando un cambio en la formación del producto basado únicamente en la composición isotópica.
Conclusiones:
- La selectividad controlada por isótopos (ICS) es una estrategia viable para dirigir las reacciones químicas.
- Este trabajo presenta el primer efecto de isótopos cinéticos que diferencia entre dos canales de productos distintos.
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