SYNTHESIS AND STRUCTURAL CHARACTERIZATION OF AN UNSYMMETRICAL ((MU)OXO)-DI-((MU)-ACETATO) MANGANESE(III,III) COMPLEX AC)(2)(H2O)(NO3)(BPY)(2)](CLO4)CENTER-DOT-CH3COOH)

The Ce4+ oxidation of Mn2+ in acetic acid in the presence of 2,2'-bipy ridine gives the unsymmetrical complex [Mn2O(OAc)(2)(H2O)(NO3)bpy)(2)] (ClO4) . CH3COOH. The crystal structure of the complex shows the coord ination of both nitrate and water to the metal ion. Each metal centre exhibits Jahn-Teller distortion and results in two types of Mn-O-OAc b onds. The formation of different high-valent manganese complexes by Ce 4+ oxidation under different conditions is discussed in the light of p ossible disproportionation and proton-coupled electron transfer reacti ons. The mode of (pseudo) Jahn-Teller distortion seen in manganese(III ,III) complexes having the Mn2O(OAc)(2)(2+) core is reviewed. Copyrigh t (C) 1996 Elsevier Science Ltd