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Reacción asimétrica carbonyl-ene catalizada por el complejo quiral N,N'-dióxido-níquel (II): una notable amplia gama
Ke Zheng1, Jian Shi, Xiaohua Liu
1Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, PR China.
Journal of the American Chemical Society
|November 5, 2008
Resumen
Un nuevo complejo de níquel ((II) -N, N'-dióxido permite reacciones altamente enantioselectivas de carbonila-eno. Esto facilita la síntesis asimétrica de valiosos compuestos alfa-hidroxi-carbonilo con excelente selectividad y rendimiento.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Síntesis asimétrica de síntesis.
- La catálisis de la catálisis.
Sus antecedentes:
- La síntesis asimétrica de los compuestos alfa-hidroxi-carbonilo es crucial para las moléculas biológicamente activas.
- El desarrollo de sistemas catalíticos eficientes para las reacciones enantioselectivas de carbonileno sigue siendo un desafío.
Objetivo del estudio:
- Desarrollar un nuevo sistema catalítico para la reacción altamente enantioselectiva de carbonileno.
- Para sintetizar compuestos alfa-hidroxi-carbonilo biológicamente relevantes.
Principales métodos:
- Utilizó un nuevo complejo de níquel ((II) -N,N extprime-dióxido como catalizador.
- Realizó reacciones de carbonileno entre derivados de glioxal/glioxilato y varios alquenos en condiciones suaves.
Principales resultados:
- Se lograron reacciones altamente enantioselectivas de carbonileno con enantioselectividades excelentes (97-99% ee).
- Tolera una amplia gama de derivados aromáticos, alifáticos y heteroaromáticos de glyoxal y glyoxilato.
- Productos obtenidos en altos rendimientos.
- Mantuvo una alta enantioselectividad incluso con una carga de catalizador reducida de 1 mol%.
Conclusiones:
- El nuevo complejo de níquel ((II) -N,N extprime-dióxido es un catalizador eficaz para las reacciones asimétricas de carbonilo-eno.
- Este método proporciona una ruta eficiente a los compuestos alfa-hidroxi-carbonilo enriquecidos enantioméricamente.
- El sistema catalítico demuestra robustez y eficiencia bajo condiciones suaves y baja carga de catalizador.
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