Silver(I)–Ferrophox Catalyzed Enantioselective Desymmetrization of Cyclopentenedione: Synthesis of Highly Substituted Bicyclic Pyrrolidines
作者:Tapas Das、Prasenjit Saha、Vinod K. Singh
DOI:10.1021/acs.orglett.5b02582
日期:2015.10.16
A highly enantioselective desymmetrization of prochiral cyclopentene-1,3-dione via [3 + 2] cycloaddition of azomethine ylide using a silver(I)–ferrophox complex has been demonstrated. The method has been utilized in the synthesis of highly functionalized enantioenriched 5,5-fused bicyclic pyrrolidine derivatives under mild reaction conditions.
General Enantioselective C−H Activation with Efficiently Tunable Cyclopentadienyl Ligands
作者:Zhi-Jun Jia、Christian Merten、Rajesh Gontla、Constantin G. Daniliuc、Andrey P. Antonchick、Herbert Waldmann
DOI:10.1002/anie.201611981
日期:2017.2.20
applicable chiral Cp ligand collection (JasCp ligands) with highly variable and adjustable structures. Their modular nature and their amenability to rapid structure variation enabled the efficientdiscovery of ligands for three enantioselective RhIII‐catalyzed C−H activation reactions, including one unprecedented transformation. This novel approach should enable the discovery of efficientchiral Cp ligands
of azomethineylides and aldehydes is explored, as hydrolysis of the resulting oxazolidine product gives facile access to valuable syn-β-aryl-β-hydroxy-α-amino esters. The use of using benzaldehyde-derived imines as the ylide precursor results in 1,3-dipolar cycloaddition with high conversions but low diastereoselectivity. In contrast, the employment of benzophenone-derived imines as the ylide precursor
An enantioselective synthesis of biologically important imidazolidines has been achieved via a tandem [3 + 2] cycloaddition/1,4-addition reaction of azomethine ylide and aza-o-quinone methides. With the use of this tool, various imidazolidinederivatives are obtained in good yields with excellent diastereoselectivities and enantioselectivities.