Indução assimétrica 1,5-Anti na adição de enolatos de boro de metilcetonas beta-oxigenadas a aldeídos

Química Nova

Luiz C. Dias¹  Andrea M. Aguilar² 

[1] ,Universidade Estadual de Campinas Instituto de Química Campinas SP ,Brasil

关键词: 1;    5-anti induction;    boron enolates;    aldol reactions;   

DOI  :  10.1590/S0100-40422007000800036

来源: SciELO

【 摘 要 】

High levels of substrate-based 1,5-stereoinduction are obtained in the boron-mediated aldol reactions of beta-oxygenated methyl ketones with achiral and chiral aldehydes. Remote induction from the boron enolates gives the 1,5-anti adducts, with the enolate pi-facial selectivity critically dependent upon the nature of the beta-alkoxy protecting group. This 1,5-anti aldol methodology has been strategically employed in the total synthesis of several natural products. At present, the origin of the high level of 1,5-anti induction obtained with the boron enolates is unclear, although a model based on a hydrogen bonding between the alkoxy oxygen and the formyl hydrogen has been recently proposed.

【 授权许可】

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