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Chiral allenamides are prepared with high levels of enantiomeric purity by [2,3]-sigmatropic rearrangement of propargylic sulfimides. The required branched propargylic sulfides are prepared by an enantioselective organocatalytic aldehyde alpha-sulfenylation followed by Corey-Fuchs alkynylation.

[reaction: see text] Conformationally restricted amino alcohols based on carbohydrate scaffolds provide flexible and fine-tuneable libraries that greatly expand the range of ligands available in the Zn(OTf)(2)-mediated addition of alkynes to aldehydes, in some cases with very high stereoselectivities.

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