The first example of a highly regio- and stereoselective catalytic method for the three-component one-pot synthesis of highly functionalized α-vinylated γ-oxo-β-amino esters is disclosed. In this catalytic triad, the CuI-catalyst selectively catalyzes the cycloaddition of the 1-alkyne and sulfonyl azide first resulting in the corresponding 1-sulfonyl-1,2,3-triazole. An α-imino RhII-carbene is generated from an open-chain α-imino diazo of the triazole, and this species reacts with γ-hydroxy α,β-unsaturated esters to form allylic (Z)-amino vinyl ethers. Rapid deconjugative [3,3]-sigmatropic rearrangement affords the α-vinyl γ-oxo-β-amino esters in high yields with high levels of diastereoselectivity.
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© 2015 American Chemical Society.