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Quiralidad inducida por ruffling: síntesis, metalización y resolución óptica de ligandos altamente no planos,

Tomasz Fekner¹, Judith Gallucci, Michael K Chan

¹Department of Chemistry, The Ohio State University, Columbus, Ohio 43210, USA.

Journal of the American Chemical Society

|January 8, 2004

Resumen

Se desarrollaron síntesis de amidas quirales cíclicas basadas en bis (benzimidazol) y sus complejos Ni (II). El obstáculo estérico y la metalización reducen significativamente las tasas de racemización, ofreciendo compuestos quirales estables.

Área de la Ciencia:

Química orgánica es la química orgánica.
Coordinación Química de la Coordinación
Química supramolecular de las moléculas.

Sus antecedentes:

Los compuestos macrocíclicos quirales son de interés por sus propiedades únicas.
La comprensión de los mecanismos de racemización es crucial para el desarrollo de moléculas quirales estables.

Objetivo del estudio:

Desarrollar rutas sintéticas eficientes para nuevas amidas quirales cíclicas basadas en bis (benzimidazol).
Investigar el impacto del obstáculo estérico, la metalización y las modificaciones estructurales (strapping) en las tasas de racemización de estos compuestos quirales.
Explorar la formación y las propiedades de sus correspondientes complejos Ni (II).

Principales métodos:

Expediente de síntesis en cinco pasos de amidas cíclicas basadas en bis (benzimidazol).
Cromatografía líquida de alto rendimiento (HPLC) de fase estacionaria quiral dinámica para estudios de racemización.
Formación y caracterización de los complejos de Ni (II).
Análisis de la estructura de un solo cristal de rayos X. Análisis de la estructura de un solo cristal de rayos X.
Técnicas de separación quiral.

Principales resultados:

Desarrolló síntesis en cinco pasos para amidas progenitoras y análogos estérilmente obstaculizados.
Se demostró que el obstáculo estérico y la metalización de Ni (II) reducen significativamente las tasas de racemicidad.
Se demostró que la incorporación de una correa ralentiza aún más la racemicidad, con tasas dependientes de la longitud de la correa.
Confirmó la geometría enrollada del núcleo bis (benzimidazol) en los complejos Ni (II) mediante análisis de rayos X.
Fácil separación quiral de ligandos y complejos lograda por HPLC quiral.

Conclusiones:

Se sintetizaron con éxito nuevas amidas quirales cíclicas basadas en bis (benzimidazol) y sus complejos Ni (II).
Las tasas de racemicidad pueden ser controladas eficazmente por el bulto estérico, la metalización y la incorporación de correas.
Estos hallazgos proporcionan una vía para diseñar moléculas quirales robustas con aplicaciones potenciales.

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