Ag-Catalyzed Asymmetric Interrupted Barton-Zard Reaction Enabling the Enantioselective Dearomatization of 2- and 3-Nitroindoles.

Org Lett

Innovation Research Center of Chiral Drugs, Institute for Advanced Study, School of Pharmacy, Chengdu University, Chengdu 610106, China.

Published: January 2022

We disclose a Ag-catalyzed asymmetric interrupted Barton-Zard reaction of α-aryl-substituted isocyanoacetates with 2- and 3-nitroindoles, which enables the dearomatization of nitroindoles and hence offers rapid access to an array of optically active tetrahydropyrrolo[3,4-]indole derivatives bearing three contiguous stereogenic centers, including two tetrasubstituted chiral carbon atoms with pretty outcomes (up to 99% yield, 91:9 dr, and 96% ee). The synthetic potential of the protocol was showcased by the gram-scale reaction and versatile transformations of the product.

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http://dx.doi.org/10.1021/acs.orglett.1c04036DOI Listing

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