Complex perovskites Ln(2)Ba(2)Cu(2)Ti(2)O(11) (Ln=La, Nd, Eu, Tb) present the topology typical of high-T-c superconducting cuprates. Doping of this series has been attempted and several cationic substitutions accomplished. Under regular reaction conditions oxygen contents readjust leaving the oxides effectively undoped. This can be overcome in certain cases by using stronger oxidizing conditions like high oxygen pressure annealing. We have also performed electrochemical oxidation of these compounds in a molten salt electrolyte. The oxygenation of Ln(2)Ba(2)Cu(2+x)Ti(2-x)O(11-y) (Ln=La, Eu) and Ln(2)Ba(2)Cu(2)Ti(2)O(11) (Ln=Tb) by means of these methods is described, and a comparison of high-pressure versus electrochemical results made.