Catalase Activity of Dinuclear Mn^III Compounds with Chlorobenzoato Bridges

Abstract

Three dinuclear Mn III compounds [{Mn(H 2 O)(NN)} 2 (μ-3-ClC 6 H 4 COO) 2 (μ-O)]X 2 with NN = 2,2Ј-bipyridine (bpy; 1 and 2) or 1,10-phenanthroline (phen; 3) and X = NO 3 -(1) or ClO 4 -(2 and 3) have been synthesized. The X-ray structures of compounds 1 and 3 were solved and the magnetic properties of the three compounds analyzed. Compounds 1 and 3 show ferromagnetic coupling, the J values being 11.8 and 5.7 cm -1 , respectively. Compound 2 displays weak antiferromagnetic behavior with a J value of -0.23 cm -1 . The catalase activity of these three compounds and that of eight analogous dinuclear[a]

Influence of the Disposition of the Anisotropy Axes into the Magnetic Properties of MnIII Dinuclear Compounds with Benzoato Derivative Bridges

“…The structural parameters of these compounds are in agreement with those reported for analogous compounds with the same [Mn 2 (μ-O)­(μ-RC 6 H 5 COO) 2 ] 2+ core. ,− ,,,,− Selected bond lengths and angles are given in Table . The Mn···Mn distance is ∼3.14 Å, and the Mn–O–Mn angle is ∼123°.…”

“…For the compounds with elongated/rhombic distortion, those with the most elongated octahedra display average parameter values of Δ = 15.6% and ρ = 3.5% (Δ/ρ = 4.5) and antiferromagnetic behavior . On the other extreme, the compound with a major degree of rhombicity presents Δ = 9.0% and ρ = 5.4% (Δ/ρ = 1.7) and ferromagnetic behavior. , Compound 1 , with Δ = 10.3% and ρ = 4.8% (Δ/ρ = 2.1), shows weak antiferromagnetic behavior, as expected for this structural distortion. Moreover, the correlation | E Mn / D Mn | versus ρ reported previously (| E Mn / D Mn |= 0.06 + 0.03 ρ, where ρ is in percent) fits well for compound 1 .…”

“…Compound 1 shows a moderate Δ value, a nonrelevant ω angle, due to the substituent in a para position, and a small τ angle (83.8°). The relative disposition of the coordination octahedra (τ) for these kinds of compounds range from 73.3 to 120°. , In general, compounds with small τ angle show antiferromagnetic behavior. Therefore, the weak magnetic behavior can be explained by the competition of both factors: the significant degree of rhombicity (Δ/ρ = 2.1) that promotes the ferromagnetic behavior and the small τ angle that works in the opposite sense.…”

Biomimetic Mn-Catalases Based on Dimeric Manganese Complexes in Mesoporous Silica for Potential Antioxidant Agent

“…During the first minute the TON follows an almost linear tendency with time; for time >1 min, the reaction slows until reaching a plateau at ∼10 min (Figure ). The activity of such compounds is of the same magnitude as some other analogues reported in the literature. , …”

Indirect effect of hydrogen bonds on the magnetic coupling on Mn(iii) dinuclear compounds

“…For the perchlorate compounds, only half of them result in one-dimensional systems by hydrogen bonding, as in the preceding case, both types are found (LW⋯ClO4 −⋯LW and LW⋯LCl). 3,6,7,10,11 Nevertheless, other cases present these interactions by connecting only two dinuclear entities to make a tetranuclear unit.2,4,6 From the magnetic viewpoint, most of these compounds show a spin ground state S = 0. Only few of them with ground spin state S = 4 have hydrogen bonds between dinuclear entities to generate a one-dimensional system.…”