Enantioselective Mannich Reactions of 3-Fluorooxindoles with Cyclic N-Sulfamidate Aldimines.

J Org Chem

Department of Chemistry and Chemical Engineering , Shanghai University of Engineering Science, 333 Longteng Road , Shanghai 201620 , China.

Published: May 2019

Both the 3-fluorooxindole and cyclic sulfamidate frameworks are important in medicinal chemistry owing to their associated biological activities. We report an approach accessing 3-fully substituted 3-fluorooxindoles, containing a benzo-fused sulfamidate subunit through highly enantioselective Mannich-type reactions between 3-fluorooxindoles and cyclic benzo-fused N-sulfamidate aldimines. These reactions are promoted by a commercially available cinchona alkaloid catalyst, accommodate a broad substrate scope, and deliver the desired products in a yield of up to 99% with an enantiomeric excess of up to 94%. A plausible reaction pathway is also presented.

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http://dx.doi.org/10.1021/acs.joc.9b00007DOI Listing

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