Indirect electrolysis of 5-(o-, m- and p-nitrophenyl)-1,2-dithiole-3-thiones in toluene is performed by phase transfer reaction with a titanium complex (C5H5)(2)Ti+ in aqueous sulfuric acid, Nitro groups are selectively reduced to amino groups without reduction of the dithiolethione ring and the resulting oxidized form of the complex is reduced at a porous graphite felt cathode by continuous recycling of the aqueous solution.