Synthesis and Structures of FeIII Complexes Bridged by Cyanorhenium Clusters

Abstract

The reaction of FeCl(L1) and FeCl(L2) [L1 = bis(3-salicylideneaminopropyl)amine, L2 = bis(3-salicylideneaminopropyl)methylamine] with the Re6 clusters [Re6Q8(CN)6]4- (Q = Se, Te) led to the formation of the nanomolecular (≈2.5 nm) compounds [(CN) 2Re6Se8{(CN)Fe(L1)}4]·7H 2O (1) and [(CN)2Re6Te 8{(CN)Fe(L2)}4]·4CH3CN·4H 2O (2). Both compounds were characterized by single-crystal X-ray diffraction analysis. Compound 1 crystallizes in the triclinic space group P1 with a = 12.2822(10), b = 14.2524(10), c = 15.8474(10) Å, α = 106.093(10)°, β = 101.992(10)°, γ = 92.438(10)°, and Z = 1. Compound 2 crystallizes in the orthorhombic space group Pbca with a = 19.3024(2), b = 16.8134(3), c = 35.9842(6) Å, and Z = 4. In these two compounds, only four pentadentate compartments are bonded to the Re6 cluster for charge balancing. The magnetic-susceptibility data show that there is no evidence for interactions between FeIII ions via the central Re6 cluster in either compound. The observed effective magnetic moments suggest that there are low-spin FeIII ions and high-spin FeIII ions mixed in each compound. © Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.