An enantioselective catalytic approach to syn deoxypropionate units combining asymmetric Cu-catalyzed 1,6- and 1,4-conjugate addition
作者:Tim den Hartog、Derk Jan van Dijken、Adriaan J. Minnaard、Ben L. Feringa
DOI:10.1016/j.tetasy.2010.04.057
日期:2010.6
approach to the synthesis of the naturally ubiquitous syn deoxypropionate motif is reported. The route comprises a new Horner–Wadsworth–Emmons reagent to prepare α,β,γ,δ-bisunsaturated thioesters. Next, two Me-substituents are introduced in high yield, regio- and enantioselectivity using sequential asymmetric Cu-catalyzed 1,6-conjugate addition, base-catalyzed olefin isomerization and Cu-catalyzed enantioselective
报道了一种合成天然无处不在的顺式脱氧丙酸酯基序的新颖的迭代方法。该路线包括用于制备α,β,γ,δ-双不饱和硫代酯的新型Horner-Wadsworth-Emmons试剂。接下来,使用连续的不对称Cu催化的1,6-共轭加成,碱催化的烯烃异构化和Cu催化的对映选择性1,4-共轭加成,以高收率,区域选择性和对映选择性引入两种Me取代基。还原为醛后,可以重复这些转化,以安装三个或多个具有1,3-顺式关系的Me基。