Cyano-Bridged Mn<sup>III</sup><sub>3</sub>M<sup>III</sup> (M<sup>III</sup> = Fe, Cr) Complexes:  Synthesis, Structure, and Magnetic Properties

Two cyano-bridged tetranuclear complexes composed of Mn(III) salen (salen = <i>N</i>,<i>N</i><i>‘</i>-ethylene bis(salicylideneiminate)) and hexacyanometalate(III) (M = Fe, Cr) in a stoichiometry of 3:1 have been selectively synthesized using {NH<sub>2</sub>(<i>n</i>-C<sub>12</sub>H<sub>25</sub>)<sub>2</sub>}<sub>3</sub>[M<sup>III</sup>(CN)<sub>6</sub>] (M<sup>III</sup> = Fe, Cr) starting materials:  [{Mn(salen)(EtOH)}<sub>3</sub>{M(CN)<sub>6</sub>}] (M = Fe, <b>1</b>; Cr, <b>2</b>). Compounds <b>1</b> and <b>2</b> are isostructural with a T-shaped structure, in which [M(CN)<sub>6</sub>]<sup>3-</sup> assumes a <i>meridional</i>-tridentate building block to bind three [Mn(salen)(EtOH)]<sup>+</sup> units. The strong frequency dependence and observation of hysteresis on the field dependence of the magnetization indicate that <b>1</b> is a single-molecule magnet.