Stereospecific Synthesis of 2‑Iminothiazolidines via Domino Ring-Opening Cyclization of Activated Aziridines with Aryl- and Alkyl Isothiocyanates

Lewis acid catalyzed domino ring-opening cyclization of activated aziridines with aryl and alkyl isothiocyanates has been accomplished leading to the formation of a wide variety of highly substituted and functionalized 2-iminothiazolidines with excellent diastereo- and enantiospecificity (de, ee up to >99%). The reaction proceeds via a Lewis acid catalyzed SN2-type ring-opening of the activated aziridine followed by a concomitant 5-exo-dig cyclization in a domino fashion to furnish the 2-iminothiazolidine derivative in excellent yields (up to 99%).

路易斯酸（Lewis acid）催化的活化氮丙啶（aziridine）与芳基、烷基异硫氰酸酯的多米诺开环环化反应已成功实现，可制备一系列高度取代且官能化的2-亚氨基噻唑烷（2-iminothiazolidine），产物具备优异的非对映异构特异性与对映异构特异性，其非对映体过量值（diastereomeric excess，de）、对映体过量值（enantiomeric excess，ee）均可达到>99%。该反应经由路易斯酸催化活化氮丙啶发生SN2型开环，随后以多米诺方式伴随5-exo-dig环化，最终以优异产率（最高可达99%）得到2-亚氨基噻唑烷衍生物。