Asymmetric Direct Vinylogous Michael Addition to 2‑Enoylpyridine N‑Oxides Catalyzed by Bifunctional Thio-Urea
2014-11-07T00:00:00Z (GMT) by
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.
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