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[(DPEPhos)(bcp)Cu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
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La oxicanización intramolecular de alquenos por catálisis cooperativa Pd/BPh3
Dennis C Koester1, Masato Kobayashi, Daniel B Werz
1Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstrasse 2, D-37077 Göttingen, Germany.
Journal of the American Chemical Society
|April 3, 2012
Resumen
Este estudio introduce una nueva reacción de oxicanización catalizada por paladio para alquenos utilizando trifenilborano. El método sintetiza eficientemente dihidrobenzofuranos sustituidos con alta selectividad.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis de la catálisis.
- Metodología sintética de la metodología sintética.
Sus antecedentes:
- La oxicanización intramolecular es una transformación sintética valiosa.
- El desarrollo de métodos catalíticos selectivos para la síntesis de moléculas complejas es crucial.
Objetivo del estudio:
- Desarrollar un nuevo sistema catalítico cooperativo para la oxicanización intramolecular de alquenos.
- Para lograr una alta quimioselectividad y regioselectividad en la síntesis de dihidrobenzofuranos.
Principales métodos:
- Catálisis cooperativa que emplea paladio y trifenilborano.
- Utilizando el 4,5-bis ((diphenylphosphino) -9,9-dimethylxanthene (Xantphos) como un ligando del paladio.
- Investigando el mecanismo que involucra la escisión de enlaces O-CN y la inserción de alquenos.
Principales resultados:
- Síntesis eficiente de varios dihidrobenzofuranos sustituidos.
- Alta quimio y regioselectividad lograda a través del uso del ligando Xantphos.
- Demostración de una nueva ruta sintética para acceder a arquitecturas moleculares complejas.
Conclusiones:
- La metodología desarrollada proporciona una nueva y poderosa herramienta para la síntesis orgánica.
- La catálisis cooperativa de paladio con trifenilborano ofrece una ruta selectiva a valiosos compuestos heterocíclicos.
- El ligando Xantphos juega un papel crítico en el control de la selectividad de la reacción.
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