Intramolecular Carboamination of Aminodienes to N-Heterocycles via C-N Bond Activation

Angew Chem Int Ed Engl. 2024 Feb 19;63(8):e202316563. doi: 10.1002/anie.202316563. Epub 2024 Jan 18.

Abstract

The catalytic transformation of ubiquitous but inert C-N bonds is highly appealing in synthetic chemistry, but the efficient cleaving inert C-N bond and simultaneous incorporation of both the cleaved C-moiety and N-moiety into the desired products has been a long-standing formidable challenge so far. Here, we developed a radical-addition triggered cyclization and C-N bond cleavage process enabled by the unique I2 /Ni or benzyl halide/Ni-catalytic system, allowing the formal insertion of diene into the inert C-N bond. This reaction features high atom economy and enables an expedient annulative carboamination of aminodienes to diverse pyrrolidines, piperidines, and tetrahydroisoquinolines. Mechanistic studies have revealed that the reaction is initiated via the generation of a benzyl radical and the formation of quaternary ammonium salt is key for the C-N bond cleavage.

Keywords: Aminodiene; Carboamination; C−N Bond Activation; N-Heterocycle.