The objective of this paper is the study of the electrochemical oxidation of p-tert-butyl anisole in acetonitrile solution and its subsequent electrodeposition on platinum anode. In dry medium, potentiostatic deposition at potential more anodic than these of the two first overlapped waves. which requires relatively high initial substrate concentration, provided an electroactive film. It is shown that whilst the formation of coated electrode at relatively low concentration is difficult in dry medium, it became possible in the presence of an excess amount of water. In the voltammetric study, we observe that the addition of water to the monomer, in the same concentrations leads to the appearance of several new consecutive redox systems, at potential region more anodic than the two overlapped waves. The number of these processes, which are attributed to oxidation of the products of the two first steps, is found to be increased with the water concentration. Combining cyclic voltammetry along with high performance liquid chromatography (HPLC), the effect of the analytical concentration of the monomer and this of the addition of water, on macroscale electrolyses is discussed. Possible reaction mechanisms as well as probable structures for oligomeric products are proposed. (C) 2010 Elsevier Ltd. All rights reserved.