Chemoselective intramolecular allylic C–H aminationversus CC aziridination through Co(ii)-based metalloradical catalysis

Abstract

Excellent chemoselectivity for intramolecular allylic C–H aminationversus CC aziridination was achieved through Co(II)-based metalloradical catalysis. Metalloradical catalyst [Co(P1)], the cobalt(II) complex of D_2h-symmetric porphyrin 3,5-Di^tBu-IbuPhyrin, was shown to be highly effective for selective intramolecular allylic C–H amination of both N-bishomoallylic and N-allylic sulfamoyl azides. The Co(II)-catalyzed intramolecular 1,6-C–H amination of these azides provides a general and efficient method to access the synthetically useful allylic 1,3-diamines under neutral and non-oxidative conditions, without complication from the competitive olefin aziridination. The origin of this remarkable chemoselectivity has direct relevance to the radical mechanism of Co(II)-based metalloradical amination.