Synthesis, Structure and Catalytic Performance of N4-Macrocycles of Fe III and Co II for Oxidation of Hydroquinone

Macrocycles and p-benzoquinones (p-BQ) have been generally connected as potential co-synergist redox models in aerobic oxidation. To get insight for the synergist oxidation of hydroquinones (H2Q), thus, we synthesized and characterized dibenzotetraaza [14]annulene type macrocycles of FeIII and CoII metal ions and described by utilizing different examinations including molar conductance, IR, UV-Vis, mass and cyclic voltammetric measurements. The spectroscopic and computational studies proposed that the macrocycles have saddle shape distorted octahedral structure. These macrocycles demonstrated the reversible and quasi-reversible redox process pursued by Randles-Sevcik equation, demonstrating the adjustment of unusual oxidation conditions of metal ions. Further, the experimental consequences presented herein enlighten the catalytic activity of these macrocycles towards the oxidation of H2Q. The results indicated that in the absence of macrocycles, the molecular oxygen is inactive with H2Q but in presence of synthesized macrocycles H2Q initiates prompt oxidation with the production of H2O2. Moreover, CoII macrocycle was found to be an efficient catalyst for the oxidation of H2Q into corresponding benzoquinones.