Improvement of the synthesis of lutetium bisphthalocyanine using the Taguchi method

In this work, a Taguchi experimental design has been used to identify impor tant factors that influence the procedure of synthesis and purification of the lutetium bisphthalocyanine (LuPc2). The working conditions have been im proved using an L-8 (2(7)) experimental design. A statistical analysis of t he experimental data revealed that the most influential factor in the yield is the amount of the starting material (AR), with a 34.4% contribution, fo llowed by the way of performing two chromatographies (C), sequentially or i n parallel (26.8%), the temperature of the reaction T (17.8%), the type of chromatography TC, standard or flash (9.1%), and lastly, the volume of the sample injected in the column (5.4%). The time of the reaction (t) and the length of the column (L-C) had little effect on the yield. Noise (N) was fo und to have a negligible influence on the throughput. Maximum yield (20.0%) was obtained when the synthesis was carried out at 280 degrees C (T) durin g 1 h 30 min (t) using 0.5 g of lutetium acetate (AR) and performing a stan dard chromatography (TC) on neutral alumina, injecting 30 ml (V) of the rea ction mixture in two columns performed in parallel (C). This yield represen ts an increase of 186% in relation to the 7% obtained before the applicatio n of the Taguchi method. Under these conditions the yield is not significan tly influenced by variability of external factors, which validates the prop osed procedure.