无金属催化炔酰胺分子内[4+2]环化反应合成四氢吲哚衍生物

Synthesis of Tetrahydroindole Derivatives via Metal-Free Intramolecular[4+2]Annulation of Ynamides

报道了无金属催化4-硅氧基-3,5-二烯炔酰胺的分子内[4+2]环化反应合成四氢吲哚衍生物的方法.在催化量三乙胺存在下,通过炔酰胺与硅氧基二烯的分子内Diels-Alder反应,可方便得到六元环环化产物.该反应条件温和、无需过渡金属催化剂、底物普适性广,为含有4-羟基氢化吲哚骨架的天然产物和活性分子的合成提供了一条简洁和高效的途径.

A metal-free reaction of 4-siloxy-3,5-diene ynamides via an intramolecular[4+2]annulation has been developed.In the presence of catalytic Et_(3)N,this protocol leads to the facile formation of six-membered cycloadducts.This reaction can proceed smoothly under mild condition without transition-metal-catalysts and its substrate scope is wide.This strategy provides a concise and practical protocol to synthesize natural product and bioactive compounds containing 4-hydroxyl hydroindole skeletons.