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Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-phosphinetriyltripiperidine]}palladium Under Mild Reaction Conditions
Published on: March 20, 2014
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Homologación de Arenas Iterativas Mediadas por Fosfina mediante el uso de Allenes
Kui Zhang1, Lingchao Cai1, Xing Jiang1
1Department of Chemistry and Biochemistry, University of California , Los Angeles, California 90095-1569, United States.
Journal of the American Chemical Society
|August 22, 2015
Resumen
Los investigadores desarrollaron una nueva reacción multicomponente utilizando trifenilfosfina (PPh3) para sintetizar naftalenos funcionalizados a partir de o-ftalaldehídos y alenos. Este método ofrece una vía versátil para los hidrocarburos aromáticos policíclicos complejos.
Área de la Ciencia:
- Química orgánica
- Química sintética
- Catálisis
Sus antecedentes:
- Las reacciones multicomponentes ofrecen vías eficientes para la síntesis de moléculas complejas.
- Los O-ftalaldehídos y los alenos son componentes versátiles en la síntesis orgánica.
- El desarrollo de nuevas metodologías sintéticas para los hidrocarburos aromáticos policíclicos es crucial.
Objetivo del estudio:
- Desarrollar una nueva reacción multicomponente para sintetizar naftalenes funcionalizados.
- Explorar los mecanismos de reacción y el alcance utilizando diferentes alenos y nucleófilos.
- Ampliar la metodología para la síntesis de hidrocarburos aromáticos policíclicos más grandes como los antracenos y los tetracenos.
Principales métodos:
- Reacción mediada por trifenilfosfina (PPh3) de los o-ftalaldehídos, los nucleófilos y los alenos monosubstituidos.
- Reacción de los o-ftalaldehídos con los alenos 1,3-disubstituidos en presencia de PPh2Et.
- Estudios mecanicistas que incluyen preparación intermedia y espectrometría de masas.
- Aplicación iterativa de la reacción utilizando ácidos carboxílicos como pronucleófilos.
Principales resultados:
- Síntesis de naftalenos funcionalizados no simétricos con C2 en rendimientos sintéticamente útiles.
- Obtención de derivados de naftaleno en rendimientos cuantitativos hasta el máximo utilizando alenos 1,3-disubstituidos y PPh2Et.
- Elucidación de un mecanismo en tándem de γ-impoluación/aldol/Wittig/deshidratación para la reacción mediada por PPh3.
- Síntesis iterativa exitosa de antracenos y tetracenos.
Conclusiones:
- La reacción multicomponente desarrollada proporciona una ruta eficiente y versátil para los naftalenos sustituidos.
- El mecanismo de reacción implica un proceso complejo en tándem, elucidado a través de estudios detallados.
- La metodología es extensible para la síntesis de sistemas aromáticos policíclicos más grandes, destacando su amplia aplicabilidad.
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