Phenazine ethosulfate

Leow reported the use of a phenazinium salt, either phenazine ethosulfate or saffanin O, as a photocatalyst for the aerobic oxidative amidation of aromatic aldehydes with secondary amines to prepare the corresponding amides in good to high yields (Scheme 62) (140L5812).This method provides access to a more ecologically safe, mild, and inexpensive generation of benzamides. 

A second methanol anode was demonstrated with methanol dehydrogenase, which was mediated by one of two species phenazine methosulfate (PMS) or phenazine ethosulfate (PES) [116]. The redox potentials of these mediators are 0.08 and 0.05 V versus SCE (also shown in Figure 9.6). It can be seen that all three mediators have a large potential difference from the methanol oxidation potential. Eliminating this potential loss was an engineering problem waiting to be solved. 

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