A rhodium(I)-xylyl-BINAP catalyzed asymmetric [2 + 2 + 2] cycloaddition of achiral conjugated aryl ynamides with various diynes is described here. This asymmetric cycloaddition provides a series of structurally interesting chiral N,O-biaryls with excellent enantioselectivity along with a modest diastereoselectivity with respect to both C-C and C-N axial chirality.
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| http://dx.doi.org/10.1016/j.tet.2009.03.078 | DOI Listing |
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