Catalytic Asymmetric Synthesis of Piperidine Derivatives through the [4 + 2] Annulation of Imines with Allenes
作者:Ryan P. Wurz、Gregory C. Fu
DOI:10.1021/ja053277d
日期:2005.9.1
there has been only very limited progress in achieving asymmetric catalysis with chiral phosphines. In this report, the first highly enantioselective variant of the Kwon annulation of imines with allenes is described. Thus, C2-symmetric chiral phosphepine 1 serves as an effective catalyst for this powerful process, furnishing an array of functionalized piperidine derivatives with very good stereoselectivity
Try bifunctional aminophosphines! An asymmetric organocatalytic [4+2] cycloaddition between α‐substituted allenoates and tosylaldimines using bifunctional N‐acyl aminophosphine catalysts was described (see scheme). This operationally simple catalytic system could provide valuable complementary results to those of the monodentate phosphine system.