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Una investigación estructural de la interacción N-B en un sistema de o-(N,N-dialquilaminometil) arilboronato

Lei Zhu¹, Shagufta H Shabbir, Mark Gray

¹Department of Chemistry and Biochemistry, The University of Texas at Austin, 78712, USA.

Journal of the American Chemical Society

|January 26, 2006

Resumen

Este estudio investigó el ácido o-pyrrolidinylmethylphenylboronic y sus complejos. Se identificaron factores que influyen en la formación de enlaces nativos N-B intramoleculares, cruciales para el diseño de nuevos quimiosensores.

Área de la Ciencia:

Química orgánica es la química orgánica.
Química supramolecular de las moléculas.
Sensores químicos de detección de sustancias químicas.

Sus antecedentes:

Las interacciones N-B en los ácidos y ésteres borónicos son clave en el reconocimiento molecular y la quimiosensorización.
La comprensión de los factores que rigen la formación de enlaces nativos N-B intramoleculares es fundamental para el diseño de sensores.

Objetivo del estudio:

Determinar los factores que influyen en la formación de un enlace dativo N-B intramolecular en el ácido o-{pyrrolidinylmethyl) fenilborónico.
Para explorar el papel del disolvente y el sustrato en la formación de enlaces nativos N-B y la solución de boronato.

Principales métodos:

Cristalografía de rayos X con rayos X.
(11) B Espectroscopia de Resonancia Magnética Nuclear (RMN) (11B) Espectroscopia de Resonancia Magnética Nuclear (RMN) es una técnica de espectroscopía de resonancia magnética nuclear (RMN) que se utiliza para la detección de rayos X.
El análisis computacional (teoría funcional de densidad)

Principales resultados:

La formación de un enlace dativo N-B y/o la inserción del disolvente (solvolisis) dependen del disolvente y del sustrato complejante.
La complejación con sustratos de retiro de electrones o bifuncionalizados en las cercanías promueve enlaces nativos N-B y la solvación de boro sp(2) a boronato sp(3).
La estructura en estado sólido del complejo catecol (7) varía con el disolvente de cristalización (cloroformo vs. metanol); los estudios computacionales predicen el enlace N-B o la solvolisis.

Conclusiones:

La identidad del disolvente y el sustrato dictan la formación de enlaces nativos N-B y la solvolización en complejos de ácido o-{pyrrolidinylmethyl) fenilborónico.
Los hallazgos sirven de guía para el diseño de nuevas tecnologías de quimiosensores que utilizan andamios de o-(N,N-dialquilaminometil) arilboronato.
Las aplicaciones potenciales incluyen la detección de moléculas fisiológicamente relevantes como los sacarídeos, los alfa-hidroxicarboxilatos y las catecolaminas.

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