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Alfa-alquilación catalítica enantioselectiva de aldehídos a través de una vía SN1

Adam R Brown¹, Wen-Hsin Kuo, Eric N Jacobsen

¹Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA.

Journal of the American Chemical Society

|June 24, 2010

Resumen

Los derivados primarios de aminotiourea catalizan las reacciones de alquilación enantioselectivas. Este estudio proporciona evidencia de un mecanismo escalonado, S(N) 1 impulsado por la unión de aniones al catalizador.

Área de la Ciencia:

Química orgánica es la química orgánica.
Catalización asimétrica por catálisis asimétrica.

Sus antecedentes:

La síntesis enantioselectiva es crucial para los productos farmacéuticos.
Los alfa-arilpropionaldehidratos son importantes intermediarios sintéticos. también conocidos como alfa-arilpropionaldehidratos.

Objetivo del estudio:

Para investigar la alquilación enantioselectiva del alfa-arilpropionaldehído.
Para dilucidar el mecanismo de reacción catalizado por los derivados primarios de aminotiourea.

Principales métodos:

Catálisis utilizando derivados primarios de la aminotiourea.
Estudios de las relaciones estructura-actividad.
Mediciones del efecto del isótopo cinético.
Análisis de la relación entre la energía libre y la energía lineal.
Experimentos con la competencia.

Principales resultados:

Los derivados primarios de aminotiourea catalizan efectivamente la alquilación enantioselectiva.
La evidencia apoya un mecanismo escalonado, S(N) 1.
La unión de aniones al catalizador es clave para la reacción de sustitución.

Conclusiones:

Los derivados primarios de aminotiourea son catalizadores eficientes para la alquilación enantioselectiva.
La reacción procede a través de un mecanismo S(N) 1 que incluye interacciones catalizador-anión.

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