Complex Alkaloid-Type Polycycles via Aza-Michael/Epoxidation of Indole-7-Carbaldehydes with Vinyl Sulfonium Salts and Alkenyl Thianthrenium Salts.

J Org Chem

Key Laboratory of General Chemistry of the National Ethnic Affairs Commission, School of Chemistry and Environment, Southwest Minzu University, Chengdu 610041, China.

Published: July 2025


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Article Abstract

An efficient synthesis of pyrroloquinolines has been developed via the aza-Michael/epoxidation cascade process in a diastereospecific manner. The domino reaction occurred properly to afford the desired tetracyclic indoles in 50->99% isolated yields. This synthetic protocol displayed especially broad substrate generality with respect to both indole-7-carbaldehydes and vinylsulfonium salts. Alkenyl thianthrenium salts were also tolerated by this protocol, affording a range of structurally distinct pyrroloquinolines. Indole-2-carbaldehydes were suitable reaction partners, as well, yielding epoxide-fused pyrrolo[1,2-]indole with good isolated yields.

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http://dx.doi.org/10.1021/acs.joc.5c00763DOI Listing

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