The cycloaddition of aziridines with isothiocyanates, isoselenocyanates and carbon disulfide has been described using pyrrolidine as catalyst on water at moderate temperature. This protocol features the use of commercial amine as catalyst and water as solvent affording a potential route for the construction of five membered heterocycles in high yields.
An Al(salen)Cl efficiently catalyzed the enantiospecific (3+2) cycloaddition of unactivated chiral aziridines with isothiocyanates to furnish functionalized iminothiazolidines at room temperature with 94–99% ee. The use of an aluminum Lewisacid as the catalyst, high enantiomeric purities, mildreaction conditions, broad substrate scope, and the high atom economy are the significant practical features
“On Water”: Efficient Iron-Catalyzed Cycloaddition of Aziridines with Heterocumulenes
作者:Mani Sengoden、Tharmalingam Punniyamurthy
DOI:10.1002/anie.201207746
日期:2013.1.7
In suspension: The reaction of aziridines with heterocumulenes in the presence of Fe(NO3)3⋅9 H2O in aqueous suspension provides access to functionalized five‐membered heterocycles in good to high yields. This protocol has a wide substrate scope, is simple, and uses a nontoxic and cheap catalyst.
Al‐catalyzed stereospecific tandem C−N/C−Se bondformation of chiral aziridines with isoselenocyanates is described with 90–99% ee and 77–91% yields. The mechanistic investigation using the computational study suggests that the reaction involves a concerted pathway (SN2). The selectivity and substrate scope are the important practical features.
铝催化立体有择的串联C-N / C-硒键形成手性氮丙啶与isoselenocyanates与90-99%ee的和77-91%的产率进行说明。使用计算研究的机理研究表明,该反应涉及一致的途径(S N 2)。选择性和底物范围是重要的实用特征。