Synthesis of mononuclear, binuclear and polymeric Mn(II)-benzoic acid complexes and study of their catalytic activity

In this study, three different Mn(II)-benzoic acid complexes, mononuclear complex [Mn(C6H5COO)(H2O)(phen)2](ClO4)(CH3OH) (1), dimeric complex [Mn2(µ-C6H5COO)2(2,2'-bipy)4]•2(ClO4) (2) and polymeric complex [Mn(µ-C6H5COO)2(4,4'-bipy)]n (3), were synthesized and characterized by single crystal X-ray diffraction and spectroscopic techniques (UV-Vis and FT-IR). Catalytic activities of the complexes were studied on alcohol and alkene oxidations. Alcohols used for oxidations studies were cinnamyl alcohol, cyclohexanol, 1-heptanol, 1-octanol and benzyl alcohol. Cyclohexene, ethylbenzene and styrene were also studied on oxidation reactions as alkenes. Optimal conditions were determined by changing different parameters like oxidant, solvent, temperature, subst./cat. and amount of oxidant for complex 1. Optimal conditions were determined for complex 2 and complex 3 by changing different temperature, oxidant and solvent parameters. The results obtained under similar experimental conditions show that catalytic oxidation activities of alcohol and alkene of complex 1 and complex 2 are approximately similar, while activity of polymeric complex 3 is lower than the others.