A Radical-Initiated Fragmentary Rearrangement Cascade of Ene-Ynamides to [1,2]-Annulated Indoles via Site-Selective Cyclization
نویسندگان
چکیده
Straightforward access to [1,2]-annulated indoles, key substructures in natural products, is highly desirable yet challenging. Herein, a radical triggered fragmentary cyclization cascade reaction of ene-ynamides presented, providing rapid into indoles by an intermolecular addition, intramolecular cyclization, desulfonylative aryl migration, and site-selective C(sp2)-N sequence. DFT calculations support oxidation N-centered species cations prior the C–N bond formation, followed unusual aza-Nazarov cyclization.
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ژورنال
عنوان ژورنال: Organic Letters
سال: 2021
ISSN: ['1523-7060', '1523-7052']
DOI: https://doi.org/10.1021/acs.orglett.1c02519