Abstract
Constant current electrolysis of 4'-substituted 2-nitrobenzenesulfenanilides (4'-OMe (1a), 4'-Me (1b), 4'-Cl (1c), 4'-COOEt (1d)) was carried out in acetonitrile containing 0.1 M ethyltributylammonium trifluoromethanesulfonate (ETBT), 1% trifluoroacetic acid, and 1% trifluoroacetic anhydride at a reticulated vitreous carbon (RVC) electrode. The quantity of electricity to be fed into the electrolytic cell was determined from the anodic potential-time curves. The yields of 2, 7-disubstituted phenazines (di-OMe (2a), di-Me (2b), di-Cl (2c), di-COOEt (2d)) were 56%, 24%, 42%, and 33%, respectively. The RVC anode was found to be useful for preparative electrolysis of 1a-d, since the considerable yields of phenazines were obtained within several minutes without the use of an expensive potentiostat.
