Asymmetric, Organocatalytic, Three-Step Synthesis of α-Hydroxy-(<i>E</i>)-β,γ-unsaturated Esters
作者:Lindsey C. Hess、Gary H. Posner
DOI:10.1021/ol100615j
日期:2010.5.7
efficient and enantiocontrolled three-step synthesis of α-hydroxy-(E)-β,γ-unsaturated esters is reported. Enantioenriched α-selenyl aldehydes, prepared in one step by asymmetric, organocatalytic α-selenylation of aldehydes, were directly subjected to a Wittig reaction followed by allylic selenide to selenoxide oxidation and final spontaneous [2,3]-sigmatropic rearrangement to yield the target compounds in 43−65%
报道了 α-羟基-( E )-β,γ-不饱和酯的有效和对映控制的三步合成。对映体富集的 α-硒基醛,通过醛的不对称有机催化 α-硒基化一步制备,直接进行 Wittig 反应,然后烯丙基硒化物氧化为硒氧化物,最终自发 [2,3]-sigmatropic 重排得到目标化合物总产率为 43-65%,ee 为 94-97%。