“<i>Syn-Effect</i>” in the Conversion of (<i>E</i>)-α,β-Unsaturated Esters into the Corresponding β,γ-Unsaturated Esters and Aldehydes into Silyl Enol Ethers
作者:Samar Kumar Guha、Atsushi Shibayama、Daisuke Abe、Maki Sakaguchi、Yutaka Ukaji、Katsuhiko Inomata
DOI:10.1246/bcsj.77.2147
日期:2004.12
The stereochemistry in the conversion of (E)-α,β-unsaturated esters into the corresponding β,γ-unsaturated esters, and that in the conversion of aldehydes into the silyl enol ethers, were investigated. The Z/E ratios of the resulting β,γ-unsaturated esters and the silyl enol ethers varied according to the γ-substituents of the (E)-α,β-unsaturated esters and the α-substituents of the aldehydes, respectively
研究了(E)-α,β-不饱和酯转化为相应的β,γ-不饱和酯以及醛转化为甲硅烷基烯醇醚的立体化学。所得β,γ-不饱和酯和甲硅烷基烯醇醚的Z/E比率分别根据(E)-α,β-不饱和酯的γ-取代基和醛的α-取代基而变化。这种现象被“syn-effect”合理化,这可能主要归因于 σ → π* 相互作用和/或 6π-电子同芳香性。