Synthesis of water soluble copper(II), manganese(III) phthalocyanines and their photocatalytic performances in benzyl alcohol photoxidation

Abstract

In this study, peripherally tetra-{[4-(3,5-dichlorophenyl)-5-pyridin-4-yl-4H-1,2,4-triazol-3-yl]thio} group substituted cobalt(II), manganese(III) phthalocyanines (BS-1-Cu, BS-1-Mn) and their water soluble derivatives (BS-1-CuQ, BS-1-MnQ) were synthesized via multistep reactions. The structure of new compounds were characterized by FT-IR, 1H-NMR, 13-CNMR, Mass, and UV visible spectroscopy. Then, photocatalytic properties of water soluble phthalocyanines (BS-1-CuQ, BS-1-MnQ) were investigated in benzyl alcohol (BA) photoxidation reaction. Photocatalytic results indicate that the former has high benzaldehyde selectivity (93%) and the latter employees with high product conversion (83%) at the same reaction conditions. The same yield of benzaldehyde (59%) was calculated with both photocatalysts at room temperature in water. The photocatalytic activity of BS-1-CuQ and BS-1-MnQ was evaluated by changing substrate amount and oxidant type. Additionally, the degradation of the BA were investigated in the presence of 0.05 g catalyst, 100 ml 0.015 M BA solution, 25 °C, 15 min in water. The recycling studies indicated that BS-1-MnQ can be used after 4 cycles, BS-1-CuQ can be used even after 3 cycles.