Highly stereoselective Brønsted acid catalyzed synthesis of spirooxindole pyrans
Jingqi Wang1, Erika A Crane, Karl A Scheidt
1Department of Chemistry, Center for Molecular Innovation and Drug Discovery, Chemistry of Life Processes Institute, Northwestern University, Silverman Hall, 2145 Sheridan Road, Evanston, Illinois 60208, USA.
Abstract:
A Brønsted acid-catalyzed Prins-type cyclization sequence to construct spirooxindole pyrans in high yields and excellent diastereoselectivity has been developed. The combination of a β-hydroxy dioxinone fragment and isatin dimethyl acetal generate oxa-spirooxindoles efficiently. These compounds are diversifiable scaffolds that tap into the rich chemistry of dioxinones.
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