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Trans-hidroboración selectiva y estereoselectiva de 1,3-Enynes catalizada por el complejo de fosfina-Pd basado en
Senmiao Xu1, Yuanzhe Zhang1, Bo Li1
1Department of Chemistry, Boston College , Chestnut Hill, Massachusetts 02467-3860, United States.
Journal of the American Chemical Society
|November 2, 2016
Resumen
Los nuevos ligandos Senphos permiten una eficiente transhidroboración catalizada por el paladio de las eninas. Esta reacción produce dienilboronatos con alta estereoselectividad, mostrando la utilidad del isosterismo BN/CC en la catálisis.
Área de la Ciencia:
- Química organometálica
- Catálisis
- Química orgánica sintética
Sus antecedentes:
- Las reacciones catalizadas por el paladio son cruciales en la síntesis orgánica.
- El desarrollo de nuevos ligandos es clave para mejorar la eficiencia y la selectividad catalítica.
- Las reacciones de hidroboración ofrecen rutas versátiles para las moléculas orgánicas funcionalizadas.
Objetivo del estudio:
- Para sintetizar nuevos monobenzofused ligandos de 1,4-azaborina de la fosfina (Senphos).
- Para investigar la utilidad de los ligandos Senphos en las transformaciones catalizadas por el paladio.
- Para explorar la síntesis estereoselectiva de los dienilboronatos de las eninas.
Principales métodos:
- Síntesis de ligandos de Senphos.
- Hidroboración trans selectiva catalizada por el paladio de las eninas terminales y internas 1,3.
- Análisis estructural de rayos X del complejo Senphos-Pd.
- Pruebas catalíticas del complejo aislado.
Principales resultados:
- Los ligandos de Senphos fueron sintetizados concisamente.
- Se logró una alta eficiencia y diastereoselectividad en la transhidroboración de eninas.
- Se observó un modo de coordinación κ2-P-η2-BC único en el complejo Senphos-Pd0).
- El complejo aislado demostró actividad catalítica para la transhidroboración.
Conclusiones:
- Los ligandos de Senphos son efectivos en la hidroboración trans selectiva catalizada por Pd.
- El enfoque de isosterismo BN/CC expande el espacio químico para la catálisis estereoselectiva.
- Este trabajo proporciona un nuevo sistema catalítico para sintetizar valiosos dienilboronatos.
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