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Copper-catalyzed propargylic C–H functionalization for allene syntheses† † Electronic supplementary information (ESI) available. CCDC 2172810. For ESI and crystallographic data in CIF or other electronic format see DOI: https://doi.org/10.1039/d3sc01501g

ABSTRACT: Allenenitriles bearing different synthetically versatile functional groups have been prepared smoothly from 5-alkynyl fluorosulfonamides in decent yields with an excellent chemo- and regio-selectivity under redox neutral conditions. The resulting allenenitriles can be readily converted to useful functionalized heterocycles. Based on mechanistic study, it is confirmed that this is the first example of radical-based non-activated propargylic C–H functionalization for allene syntheses. A copper catalysed 1,5-HAT-based propargylic C–H cyanation affording tri- or tetra-substituted allenenitriles with excellent chemo- and regio-selectivity has been developed.

SUBMITTER: Zhang D

PROVIDER: S-EPMC10466309 | biostudies-literature | 2023 Aug

REPOSITORIES: biostudies-literature

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