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Updated: Aug 6, 2026
06:46
Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Generación directa y estereospecífica de alcoholes alelicos (Z) -disubstituidos
Sang-Jin Jeon1, Ethan L Fisher, Patrick J Carroll
1P. Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104-6323, USA.
Journal of the American Chemical Society
|July 27, 2006
Resumen
Una nueva síntesis de un solo bote produce alcoholes alelicos altamente funcionalizados (Z) disubstituidos. Este método convierte eficientemente las alquinas y aldehídos en valiosos productos de alcohol quiral con alta estereoselectividad.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Química sintética de la química sintética.
- Síntesis estereoselectiva de síntesis.
Sus antecedentes:
- Los alcoholes alilicos son bloques de construcción cruciales en la síntesis orgánica.
- El desarrollo de métodos eficientes y estereoselectivos para su preparación sigue siendo un desafío clave.
- Los métodos existentes a menudo requieren múltiples pasos o carecen de un amplio alcance de sustrato.
Objetivo del estudio:
- Introducir un novedoso método de una sola olla para la síntesis de alcoholes alelicos (Z) disubstituidos.
- Para lograr altos rendimientos y estereoselectividad en la formación de estos compuestos.
- Para explorar la diastereoselectividad de la reacción con aldehídos quirales.
Principales métodos:
- Hidroboración de 1-bromo-1-acetileno con diciclohexil borano.
- Formación de un reactivo de vinilzinco (Z) disubstituido a través de la reacción con t-BuLi y transmesación.
- Reacción in situ del reactivo vinilzinco con varios aldehídos.
Principales resultados:
- Se obtuvieron altos rendimientos (81-97%) de alcoholes alelicos (Z) disubstituidos.
- La reacción demostró una excelente estereoselectividad, con diastereoselectividades que van desde 6:1 hasta 18:1.
- El producto anti-Felkin se formó predominantemente en adiciones a aldehídos quirales.
Conclusiones:
- El método de un solo bote desarrollado proporciona una ruta eficiente a los alcoholes alelicos altamente funcionalizados (Z) -disubstituidos.
- El método ofrece altos rendimientos y un excelente control estéreo, particularmente en adiciones a sustratos quirales.
- Este enfoque representa un avance significativo en la síntesis de complejos derivados del alcohol alilico.
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