Synthesis of γ-Butyrolactams by Photoinduced PhSe Group Transfer Radical Cyclization and Formal Synthesis of (±)-Isocynometrine with Diphenyldiselenide as Promoter
作者:Dan Yang、Gao-Yan Lian、Hai-Feng Yang、Jin-Di Yu、Dan-Wei Zhang、Xiang Gao
DOI:10.1021/jo9017099
日期:2009.11.20
with high regioselectivity and stereoselectivity from N-alkenyl α-PhSe β-keto amides. Reaction outcomes were modulated by the steric effect of the substituents on the nitrogen atom of the cyclization precursors and the stereoelectronic effect of the substrates. Diphenyldiselenide, as an additive, was found to promote ring closure. The advantage of this strategy in natural product synthesis is demonstrated
我们已经开发出了一种通过光诱导PhSe基团转移自由基环化反应来构建氮杂环的策略。从N-烯基α-PhSeβ-酮酰胺制备的反式-α,β-二取代γ-丁内酰胺(2-吡咯烷酮)具有良好的选择性和立体选择性,产率高(38-73%)。反应结果受环化前体氮原子上取代基的空间效应和底物的立体电子效应的调节。发现二苯基二硒化物作为添加剂可促进闭环。该策略在天然产物合成中的优势通过(±)-异氰尿素的正式合成得到证明。