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La oxidación intramolecular de los hidroxamatos O-alquilo insaturados: una entrada notablemente versátil para los
Duncan J Wardrop1, Edward G Bowen, Raymond E Forslund
1University of Illinois at Chicago, Department of Chemistry, 845 West Taylor Street, Room 4500, Chicago, Illinois 60607-7061, USA. wardropd@uic.edu
Journal of the American Chemical Society
|October 1, 2009
Resumen
Un nuevo método versátil prepara hidroxilactamas de cinco a ocho miembros mediante oxamidación mediada por yodo (III). Esta transformación estereospecífica y regioselectiva ofrece una nueva ruta sintética para la síntesis compleja de amida cíclica.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Metodología sintética de la metodología sintética.
- Química Medicinal La Química Medicinal es el campo de la Química Medicinal.
Sus antecedentes:
- Los lactamos son compuestos heterocíclicos cruciales que se encuentran en numerosos productos farmacéuticos.
- La síntesis eficiente de lactamas de tamaño medio (anillos de cinco a ocho miembros) sigue siendo un desafío sintético.
- El desarrollo de nuevas estrategias de ciclización es esencial para acceder a diversos andamios de lactam.
Objetivo del estudio:
- Desarrollar un método versátil y eficiente para sintetizar hidroxilactamas de cinco a ocho miembros.
- Explorar una nueva reacción de oxamidación mediada por yodo (III) para la formación de lactamo.
- Investigar los resultados estereoquímicos y regioquímicos de esta nueva transformación sintética.
Principales métodos:
- Se utilizó la oxamidación mediada por yodo (III) de hidroxamatos O-alquilo insaturados.
- Investigó el mecanismo de reacción, proponiendo intermediarios de iones de nitrenio singlet y N-acil-N-alkoxyaziridinium bicíclicos.
- Examinó la estereospecificidad y la regioselectividad de la reacción en 22 sustratos diferentes.
Principales resultados:
- Preparó con éxito una gama de hidroxilactamas de cinco a ocho miembros.
- Demostró la versatilidad del enfoque de oxamidación mediada por yodo (III).
- Se observó una alta estereospecificidad y regioselectividad en la mayoría de los casos probados, lo que indica resultados de reacción predecibles.
- Proporcionó conocimientos mecanicistas sobre los intermediarios propuestos.
Conclusiones:
- La oxamidación mediada por yodo desarrollada es un método poderoso y versátil para la síntesis de hidroxi lactamo.
- Este método ofrece una ruta estereospecífica y altamente regioselectiva a las valiosas estructuras lactamicas de cinco a ocho miembros.
- Los hallazgos contribuyen a una nueva estrategia sintética para acceder a compuestos heterocíclicos complejos relevantes para el descubrimiento de fármacos.
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