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Updated: Jul 17, 2026

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
An unusual stereoselectivity in the anomeric substitution with carbamates promoted by HNTf2
Changhong Ko1, Richard P Hsung
1Division of Pharmaceutical Sciences and Department of Chemistry, Rennebohm Hall, 777 Highland Avenue University of Wisconsin, Madison, WI 53705-2222, USA.
Abstract:
An unexpected stereoselective anomeric substitution with carbamates promoted by HNTf2 is described here. Our experiments suggest that the observed diastereoselectivity is a result of thermodynamic equilibration of protonated N-acyl aminals.
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