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Tandem 6pi-electrociclado y cicloadición de nitrodienos para obtener acetalos nitroso multicíclicos
1Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, USA.
Journal of the American Chemical Society
|June 19, 2010
Resumen
Los nitrodienos se someten a una reacción de dominó para crear acetales nitroso funcionalizados. Estos compuestos pueden ser convertidos en hidroxiamidas y aminoácidos valiosos.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Química sintética de la química sintética.
Sus antecedentes:
- Los nitrodienos son compuestos orgánicos versátiles.
- Las reacciones de electrociclado son transformaciones clave en la síntesis orgánica.
Objetivo del estudio:
- Desarrollar un nuevo proceso de dominó de una sola olla y dos pasos para sintetizar acetalos nitroso altamente funcionales.
- Explorar el alcance y la selectividad de la [3 + 2] cicloadición dipolar con nitronatos generados in situ.
- Demostrar la utilidad de los acetalos de nitroso sintetizados a través de la hidrogenólisis selectiva.
Principales métodos:
- Reorganización térmica de los nitrodienos a través de la electrociclado 6π.
- En tándem [3 + 2] cicloadición dipolar con varios dipolarófilos.
- Hidrogenización selectiva de los productos de acetal de nitroso.
Principales resultados:
- El proceso de dominó produce eficientemente acetalos nitroso altamente funcionalizados con buena selectividad facial y exo.
- Una amplia gama de dipolarófilos ricos en electrones, neutrales y deficientes son compatibles con la cicloadición.
- La hidrogenólisis selectiva proporciona acceso a las amidas hidroxi hidrociclicas espirocíclicas densamente funcionalizadas y a los ácidos hidroxi gamma-amino.
Conclusiones:
- La reacción de dominó desarrollada ofrece una ruta potente y eficiente a los complejos nitrosoacetales.
- Los acetalos de nitroso sintetizados sirven como valiosos precursores para diversas moléculas funcionalizadas, incluidas las amidas hidroxi-espirocíclicas y los ácidos gamma-amino.
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