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Hidrogenación radical biocatalítica y asimétrica de alquenos no activados

Jaicy Vallapurackal¹, Rajib Mandal¹, Justin Bossenbroek¹

¹Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, CA, USA.

Science (New York, N.Y.)

|October 16, 2025

Resumen

Los investigadores desarrollaron nuevas enzimas hemo para la hidrogenación asimétrica de alceno, reduciendo las olefinas no activadas desafiantes utilizando un nuevo mecanismo de radicales promovido por silano. Este avance ofrece un enfoque biocatalítico sostenible para la síntesis química.

Área de la Ciencia:

Biocatálisis
Química orgánica
Enzimología

Sus antecedentes:

La hidrogenación enzimática de alquenos es crucial, pero se limita a los sustratos con deficiencia de electrones a través de la transferencia de hidruro.
El desarrollo de métodos biocatalíticos para las olefinas no activadas es un desafío sintético importante.

Objetivo del estudio:

Diseñar enzimas hemo para la reducción asimétrica de alquenos no activados.
Establecer una nueva vía enzimática para la hidrogenación de las olefinas mediante la transferencia de átomos de hidrógeno.

Principales métodos:

Ingeniería de enzimas hemo con un ciclo redox hemo-cisteína promovido por silano.
Utilizando la transferencia secuencial de átomos de hidrógeno para la reducción de alquenos.
Realizar estudios mecanicistas y computacionales para dilucidar el proceso radical.

Principales resultados:

Se han desarrollado enzimas hemo promiscuas y tolerantes al oxígeno capaces de reducir alquenos 1,1-disubstituidos, tri- y tetrasubstituidos.
Se logra la hidrogenación asimétrica en una escala de gramos en condiciones ambientales utilizando hierro abundante en la Tierra.
Habilitado el etiquetado asimétrico de isótopos divergentes de sitio utilizando fuentes de átomos de hidrógeno ortogonales.

Conclusiones:

Se introdujo un nuevo enfoque bioquímico para la reducción estereoselectiva de las olefinas.
Demostró una plataforma versátil para la hidrogenación biocatalítica de próxima generación.
Se estableció un mecanismo radical escalonado para la hidrogenación catalizada por hemo promovida por silano.

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