793653-30-2Relevant academic research and scientific papers
Structural characterization of a new manganese(III)-salen complex [H2salen = N,N′-bis(salicylidene)ethane-1,2-diamine] and study of its electron transfer kinetics with hydroquinone and catechol
Panja, Anangamohan,Shaikh, Nizamuddin,Ali, Mahammad,Vojtí?ek, Pavel,Banerjee, Pradyot
, p. 1191 - 1198 (2003)
The octahedral manganese(III) complex, [Mn(salen)Cl(H2O)]·H2O (H2salen = N,N′-bis(salicylidene)ethane-1,2-diamine), has been synthesized and structurally characterized by single-crystal X-ray diffraction study. The X-ray structural analysis shows that the metal center is six-coordinate with distorted octahedral geometry. In this compound, the Mn-Cl and Mn-OH2 bond lengths are 2.621(6) and 2.333(2) A?, respectively, slightly longer than the usual values. The kinetics of electron transfer reaction of the complex with catechol and hydroquinone has been followed spectrophotometrically over the pH range 5.75-8.15 at 30 °C. The nature of the kinetic trace is indicative of a biphasic reaction with each reductant. Detailed analysis of kinetic data supports the formation of a relatively stable intermediate complex between manganese(III) and the dihydroxybenzenes (H2A) at the initial stage. The decay of the intermediate is the bimolecular electron transfer process involving another molecule of reductants leading to the manganese(II) complex and benzoquinones. MnIII(salen)(H2O)(OH) generated in situ from the aquation and proton equilibrium of the parent complex has been assigned to be the reactive species during the formation of the intermediate. The corresponding species for the redox step is MnIII(L)(H2O)(HA), sufficient experimental evidence for which has been gathered from pH-rate profiles.
