Syntheses, structures, and magnetic properties of cyano- and phenoxide-bridged Fe(III)-Mn(III) tetrameric assemblies formed by blocked fac-Fe tricyanide with aliphatic rings.

Three tetranuclear clusters [(Tp(Me,mt3))Fe(CN)3Mn(L)]2 (1, L = 5-Clacphmen; 2, L = 5-Clsalen; 3, L = 5-MeOsalen; Tp(Me,mt3) = hydrotris(3-methyl-4,5-propylene-5-methylpyrazol-1-yl)borate) were prepared by assembling the fac-Fe tricyanide with the corresponding Mn Schiff bases. The assembled molecules are linked by cyanide and phenoxide bridges. Weak π-π contacts between molecules are evident in these clusters. Compounds 1-3 exhibit slow relaxation of the magnetization. The phenoxide linkers mediate ferromagnetic coupling between the Mn centers, which is ascribed to the long axial Mn-O* length. The overall magnetic exchange coupling nature of the Fe-C≡N-Mn route is accounted for by the important structural parameters of bridging pathways such as Mn-N(cyano) length, Mn-N(cyano)-C(cyano) angle, and C(eq)-Fe···Mn-N(eq) (eq = equatorial) torsion angle.