The mechanism of saccharide osotriazole formation

The first step in the proposed mechanism is the formation of an osazone–Cu(II) complex that undergoes a one-electron shift from the nitrogen of the ligand to the metal in the complex which is reduced to Cu(I). This complex decomposes with the liberation of Cu(I)+, a ligand radical which undergoes a set of one-electron shifts to form a phenylimine radical (Ph–NH)radical dot and the triazole. The Cu(I)+ produced is converted to Cu(II)2+ and Cu0 by disproportionation.