Recent Progress in Free Radical Transformations of Allenamides.

Allenamides are special allenes, and the unique reactivity, selectivity (both stereoselective and regionally selective) and stability of allenamides have been widely studied. In this review, the development of the free radical transformation of allenamides over the last few years will be summarized. This review discusses in detail in three parts: intermolecular radical addition to C- X (X = N, S, O, Se) bonds, metal salt mediated cyclization of allenamides, and photocatalytic cyclization of allenamides. In addition, reasonable details of the mechanisms are provided for the vast majority of these transformations.