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Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
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Adiciones cíclicas intermoleculares au catalizadas [2+2] entre cloroalquinas y alquenos no activados
Yu-Bin Bai1,2, Zaigang Luo2, Yuguang Wang2
1Shaanxi Key Laboratory of Natural Products & Chemical Biology, College of Chemistry & Pharmacy , Northwest A&F University , Yangling 712100 , China.
Journal of the American Chemical Society
|April 6, 2018
Resumen
La catálisis del oro permite cicloadiciones [2+2] eficientes de cloroalkinas con alquenos no activados, incluso desafiando a los monosubstituidos. Esta reacción catalizada por oro ofrece una regioselectividad y una estereospecificidad superiores para sintetizar productos valiosos de ciclobuteno.
Área de la Ciencia:
- Química orgánica
- Catálisis
- Metodología sintética
Sus antecedentes:
- La cicloadición [2+2] es una reacción clave para sintetizar ciclobutenos tensados.
- Los métodos existentes a menudo luchan con alquenos no activados o monosubstituidos.
Objetivo del estudio:
- Desarrollar cicloadiciones intermoleculares [2+2] eficientes catalizadas por el oro.
- Para utilizar cloroalquinas y alquenos no activados como sustratos.
- Superar las limitaciones de las estrategias sintéticas existentes para la síntesis de ciclobuteno.
Principales métodos:
- Utilizando la catálisis del oro para las reacciones de cicloadición intermolecular [2+2].
- Utilizando dos tipos distintos de cloroalquinas y varios alquenos no activados.
- Investigación de las reacciones con alquenos no activados monosubstituidos y 1,2-disubstituidos.
Principales resultados:
- Se han logrado cicloadiciones eficientes catalizadas por oro [2+2] entre cloroalquinas y alquenos no activados.
- Se ha demostrado una reactividad sin precedentes con alquenos no activados monosubstituidos.
- Obtuvo excelentes selectividades regionales, superando los precedentes de la literatura.
- Se han observado en gran medida reacciones estereospecíficas con alquenos no activados 1,2-disubstituidos.
- Productos de ciclobuteno sintetizados en una escala cercana al gramo.
Conclusiones:
- Desarrolló una versátil cicloadición catalizada por oro para la síntesis de ciclobuteno valioso.
- El método amplía los derivados accesibles del ciclobuteno a través de reacciones de acoplamiento cruzado posteriores.
- Destaca la utilidad sintética de esta reacción bimolecular para la construcción de moléculas complejas.
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