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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
Síntesis asimétrica catalítica de oxetenos estables a través de la cicloadición [2+2] promovida por el ácido de Lewis
Kohsuke Aikawa1, Yūta Hioki, Natsumi Shimizu
1Department of Applied Chemistry, Tokyo Institute of Technology, Tokyo 152-8552, Japan.
Journal of the American Chemical Society
|November 11, 2011
Resumen
Un nuevo método catalítico permite la síntesis enantioselectiva de derivados estables de oxeteno utilizando trifluoropyruvato y alquinas. Estos bloques de construcción quirales son valiosos para productos farmacéuticos y agroquímicos.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis de la catálisis.
- Metodología sintética de la metodología sintética.
Sus antecedentes:
- Los derivados del oxeteno son importantes motivos estructurales.
- La síntesis enantioselectiva de compuestos trifluorometilados sigue siendo un desafío.
Objetivo del estudio:
- Desarrollar una cicloadición [2 + 2] altamente enantioselectiva y de economía atómica para sintetizar derivados estables del oxeteno.
- Establecer un método catalítico práctico para la producción de compuestos quirales sustituidos por CF 3 .
Principales métodos:
- Se utilizó un catalizador dicationic (S) -BINAP-Pd para la reacción de cicloadición [2 + 2].
- Empleó varios alquinos y trifluoropiruvato como sustratos.
- Caracterizó los derivados de oxeteno resultantes utilizando análisis de rayos X.
Principales resultados:
- Logró la primera síntesis enantioselectiva de derivados estables del oxeteno.
- Se ha demostrado una alta estereoselectividad en la transformación de los derivados de oxeteno en compuestos sustituidos por CF.
- Mostró la practicidad del proceso catalítico con baja carga de catalizador (hasta 0,1 mol %).
Conclusiones:
- El sistema catalítico desarrollado proporciona una ruta eficiente a los derivados de oxeteno enriquecidos enantioméricamente.
- Estos derivados del oxeteno sirven como versátiles bloques de construcción quirales para productos farmacéuticos y agroquímicos.
- La metodología facilita la síntesis de valiosos compuestos sustituidos por CF3 con alto estereocontrol.
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