In methanol, the reaction of Mn(ClO4)(2)-6H(2)O and 1,2-bis(biacetylmonoximeimino)ethane (H(2)bamen) in the presence of triethylamine affords a trinuclear complex having the formula [Mn-3(mu(3)-O)(mu(3)-bamen)(3)]ClO4.2H(2)O. The structure of this complex shows a symmetric planar central {Mn-3(III)(mu(3)-O)} unit coordinated to three hexadentate bridging (via oximate groups) ligands. The N4O3 coordination sphere around each metal center is very close to pentagonal-bipyramidal. A cyclic voltammogram of the complex displays two reversible and an irreversible response due to Mn-3(III) --> (Mn2MnIV)-Mn-III, (MnMnIV)-Mn-III --> (MnMn2IV)-Mn-III, and (MnMn2IV)-Mn-III --> Mn-3(IV) oxidation processes, respectively. Cryomagnetic data reveal that the complex is ferromagnetic.