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Adiciones altamente diastereoselectivas controladas por quelación a las α-sililoxi cetonas

Gretchen R Stanton¹, Gamze Koz, Patrick J Walsh

¹P. Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104-6323, USA.

Journal of the American Chemical Society

|May 4, 2011

Resumen

Este estudio introduce un nuevo método para las adiciones de organozinco a las α-hidroxiketonas protegidas por sililo, logrando una alta diastereoselectividad. El método permite la síntesis controlada por quelación de valiosos productos antidiol.

Área de la Ciencia:

Química orgánica es la química orgánica.
Síntesis estereoselectiva de síntesis.

Sus antecedentes:

Los modelos tradicionales predicen los productos anti-diol de las adiciones organometálicas a las α-hidroxiketonas protegidas por sililo.
Las adiciones controladas por quelación rara vez se informan para estos sustratos.

Objetivo del estudio:

Desarrollar un método general y altamente diastereoselectivo para las adiciones de organozinco a las α-sililoxi cetonas.
Para lograr la síntesis controlada por quelación de productos diólicos específicos.

Principales métodos:

Adición de dialquilzincos y varios reactivos de vinilozinco a las α-sililoxi cetonas.
Utilizando ácidos de Lewis de haluro de zinc alquilo (RZnX) para promover el control de la quelación.

Principales resultados:

El método desarrollado proporciona una alta diastereoselectividad (dr ≥18:1) para productos de adición controlados por quelación.
Compatibilidad demostrada de los reactivos organozinc con diversos grupos funcionales.

Conclusiones:

Se ha establecido un método novedoso, general y altamente diastereoselectivo para las adiciones de organozinco controladas por quelación a las α-sililoxi cetonas.
Este método ofrece un potencial significativo para la síntesis de moléculas complejas debido a su tolerancia al grupo funcional.

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