Gold- and Silver-Catalyzed Tandem Amination/Ring Expansion of Cyclopropyl Methanols with Sulfonamides as an Expedient Route to Pyrrolidines
作者:Weidong Rao、Philip Wai Hong Chan
DOI:10.1002/chem.200801242
日期:2008.11.17
An efficient synthetic route to pyrrolidines that relies on AuCl/AgOTf-catalyzed tandem amination/ring expansion of substituted cyclopropyl methanols with sulfonamides is reported herein. The reactions proceed rapidly at 100 degrees C with catalyst loadings as low as 2 mol % and produce the pyrrolidine products in yields of 30-95 %. The method was shown to be applicable to a broad range of cyclopropyl
本文报道了依赖于AuCl / AgOTf催化的串联磺胺化/取代的环丙基甲醇与磺酰胺的环吡咯烷酮的有效合成途径。反应在100℃下以低至2mol%的催化剂负载快速进行,并以30-95%的产率产生吡咯烷产物。已证明该方法适用于多种环丙基甲醇,包括未活化的环丙基甲醇和含有吸电子,给电子和空间需求取代基的磺酰胺底物。提示该机理涉及通过AuCl / AgOTf催化剂活化醇底物,然后使原料电离,这引起环丙烷部分的开环并被磺酰胺亲核试剂捕获。