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Generación directa regioselectiva y quimioselectiva de compuestos aromáticos de aluminio funcionalizados utilizando
Masanobu Uchiyama1, Hiroshi Naka, Yotaro Matsumoto
1Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan. uchiyama@mol.f.u-tokyo.ac.jp
Journal of the American Chemical Society
|August 26, 2004
Resumen
Un nuevo método de orto-iluminación directa genera compuestos de aluminio aromáticos funcionalizados. Este enfoque permite la formación eficiente de enlaces C-C para la síntesis de moléculas complejas.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Química orgánica sintética y orgánica.
Sus antecedentes:
- La orto-iluminación dirigida es una herramienta poderosa para la funcionalización de los anillos aromáticos.
- Los métodos existentes a menudo requieren condiciones duras o grupos de dirección específicos.
Objetivo del estudio:
- Desarrollar un método directo novedoso, regioselectivo y quimioselectivo para generar compuestos de aluminio aromáticos funcionalizados.
- Para explorar la utilidad de estos intermediarios en reacciones posteriores de formación de enlaces C-C.
Principales métodos:
- Preparación de triisobutil (((tetrametilpiperidino) aluminato (iBu3Al ((TMP) Li) a partir de triisobutilaluminio (iBu3Al) y tetrametilpiperiduro de litio (LTMP) en THF.
- Deprotonativo dirigido orto-iluminación de los benzenos funcionalizados y los heteroaromáticos.
- El atrapamiento electrófilo de los intermedios de aluminio generados con yodo (I2).
- Reacciones de acoplamiento cruzado catalizadas por cobre y paladio utilizando los aluminatos aromáticos funcionalizados.
Principales resultados:
- Generación exitosa de derivados de aluminio orto-funcionalizados aromáticos y heteroaromáticos, incluidos los con grupos ciano, amida y halógeno.
- Síntesis eficiente de compuestos aromáticos 1,2- y 1,2,3-multisubstituidos a través de la aluminación directa y el atrapamiento electrófilo.
- Alta eficiencia y selectividad en las reacciones de formación de enlaces C-C catalizadas por cobre y paladio utilizando los intermediarios de aluminio.
Conclusiones:
- El reactivo iBu3Al(TMP)Li desarrollado proporciona una vía versátil y efectiva para la orto-iluminación directa.
- Este método ofrece una vía conveniente para diversos compuestos de aluminio aromáticos funcionalizados.
- Los intermediarios generados son valiosos precursores para la formación de enlaces C-C en la síntesis de moléculas complejas.
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