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Amidación enantioselectiva catalizada por metalloenzimas por medio de la inserción de nitreno en enlaces C3H no
Kun Yu1, Zhi Zou1, Nico V Igareta1
1Department of Chemistry, University of Basel, Mattenstrasse 24a, BPR 1096, Basel CH-4058, Switzerland.
Journal of the American Chemical Society
|July 20, 2023
Resumen
Una metaloenzima artificial (ArM) permite la amidación C-H enantioselectiva de los enlaces C ((sp3) -H no activados. Este avance logró una alta actividad y selectividad, allanando el camino para la síntesis de moléculas nuevas que contienen nitrógeno.
Área de la Ciencia:
- Catálisis
- La bioquímica
- Química orgánica
Sus antecedentes:
- La amidación C-H enantioselectiva es crucial para sintetizar compuestos valiosos que contienen nitrógeno.
- Se han desarrollado métodos catalíticos tanto enzimáticos como homogéneos para la amidación C-H.
Objetivo del estudio:
- Desarrollar una nueva metalloenzima artificial (ARM) para la amidación C-H enantioselectiva.
- Optimizar el ARM para una mayor actividad y selectividad.
Principales métodos:
- Se ancló un complejo de iridio dentro de la estreptavidina para crear el ARM.
- Se realizó una optimización quimiogenética del cofactor de iridio y de la streptavidina.
- Se emplearon cálculos de cristalografía de rayos X y mecánica cuántica-molecular (QM-MM).
Principales resultados:
- El ARM catalizó con éxito la amidación enantioselectiva de enlaces C ((sp3) -H no activados.
- A través de la optimización se lograron mejoras significativas en la actividad y en la enantioselectividad.
- Se obtuvieron cifras de facturación (TON) superiores a 700 y un exceso enantiomérico (ee) del 92%.
Conclusiones:
- El ARM desarrollado, una insertasa de nitreno artificial (ANIasa), es un catalizador altamente eficaz para la amidación de C-H.
- Las interacciones de la segunda esfera de coordinación dentro del ARM son críticas para su mejor rendimiento catalítico.
- Este trabajo proporciona información sobre el diseño de enzimas metálicas avanzadas para transformaciones químicas complejas.
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