DIMANGANESE(II) COMPLEXES OF A NEW PHENOL-BASED DINUCLEATING LIGAND WITH 2 AMINO CHELATING ARMS - SYNTHESIS, STRUCTURE AND CATALASE-LIKE ACTIVITY

A new phenol-based dinucleating ligand with two amino chelating arms, 2,6-bis{[N-(2-dimethylaminoethyl)-N-methyl] aminomethyl}-4-methylpheno late (L(-)), formed dinuclear manganese(ii) complexes [Mn(2)L(p-XC(6)H (4)CO(2))(2)(NCS) (MeOH)] (X = H 1, CI 2, Me 3 or NO2 4). X-Ray analys is revealed that complex 1 crystallizes in the monoclinic space group P2(1)/c. a = 12.607(3), b = 19.566(6), c = 16.743(5) Angstrom and beta = 107.56(2)degrees. The two manganese ions are bridged by the phenoli c oxygen and two benzoate groups. The NCS- ion is co-ordinated to one of the manganese ions through its nitrogen and the methanol molecule t o the other. providing distorted-octahedral geometries around each man ganese. Magnetic susceptibility measurements over the temperature ii r ange 4.2-300 K indicated a weak antiferromagnetic interaction (J = -3 to -5 cm(-1) based on (H) over cap = -2J (S) over cap(1) .(S) over cap (2)). The complexes show a catalase-like activity in disproportionatin g H2O2 in dimethylformamide. The rate of dioxygen evolution was propor tional to the concentration of H2O2 and the rate constant decreased in the order 1 (X = H) > 2(CI) > 3(Me) > 4(NO2).