Chemoselective Amination of Propargylic C(sp 3 )H Bonds by Cobalt(II)‐Based Metalloradical Catalysis

Highly chemoselective intramolecular amination of propargylic C(sp 3 )H bonds has been demonstrated for N‐bishomopropargylic sulfamoyl azides through cobalt(II)‐based metalloradical catalysis. Supported by D 2h ‐symmetric amidoporphyrin ligand 3,5‐Di t Bu‐IbuPhyrin, the cobalt(II)‐catalyzed CH amination proceeds effectively under neutral and nonoxidative conditions without the need of any additives, and generates N 2 as the only byproduct. The metalloradical amination is suitable for both secondary and tertiary propargylic CH substrates with an unusually high degree of functional‐group tolerance, thus providing a direct method for high‐yielding synthesis of functionalized propargylamine derivatives.