N-acyl (-CHO, -COMe, -COOMe, -COPh, -COCF3) and N-sulfonyl (-SO2Me, -SO2Ph, -SO2 (p-tolyl) piperidines were synthesized and studied by cyclic voltammetry. Their anodic methoxylation was performed at various anodes (carbon rod, carbon felt, glassy carbon, Pt and PbO2), in the presence of different electrolytes (But(4)NClO(4), Et4NBF4 and Et4NOTs), applying a current density of 20 mA cm(-2). Methoxylation on graphite with Et4NOTs favored the formation of a-monomethoxy products whereas in the presence of Et4NBF4, the alpha,alpha'-dimethoxy derivatives become predominant in selected cases. (C) 2015 Elsevier Ltd. All rights reserved.