Asymmetric Direct Vinylogous Michael Addition to 2‑Enoylpyridine N‑Oxides Catalyzed by Bifunctional Thio-Urea
datasetposted on 07.11.2014, 00:00 authored by Subhrajit Rout, Sumit K. Ray, Rajshekhar A. Unhale, Vinod K. Singh
Catalytic enantioselective direct vinylogous Michael addition of α,α-dicyanoalkenes to 2-enoylpyridine N-oxides with a bifunctional organocatalyst is described. The methodology offers an efficient way to install an asymmetric carbon–carbon bond at the γ-position of α,α-dicyanoalkenes in excellent regio-, diastereo-, and enantioselectivity. Further, application in desymmetrization of achiral α,α-dicyanoalkene to access highly functionalized enantioenriched cyclohexylidenemalononitrile derivatives has been demonstrated.