Influence of β-Substituents in Aldol Reactions of Boron Enolates of β-Alkoxy Methylketones
作者:Luiz C. Dias、Emílio C. de Lucca、Marco A. B. Ferreira、Danilo C. Garcia、Cláudio F. Tormena
DOI:10.1021/ol102303p
日期:2010.11.5
the boron-mediated aldol reactions of β-tert-butyl methylketones with achiral aldehydes, independent of the nature of the β-alkoxy protecting group (P = PMB or TBS). The analysis of the relative energies of the transition structures by theoretical calculations using the density functional B3LYP shows relative energies favoring the corresponding OUT-1,5-SYN transition structures, explaining the observed
在β-叔丁基甲基酮与非手性醛的硼介导的醛醇缩合反应中,可实现中等程度的基于底物的1,5-顺式立体控制,而与β-烷氧基保护基的性质无关(P = PMB或TBS)。通过使用密度泛函B3LYP的理论计算对过渡结构的相对能量进行分析,结果表明相对能量有利于相应的OUT-1,5- SYN过渡结构,从而解释了所观察到的1,5- syn立体感应。