Synthesis, Structure and Characterizations in Solid State and Solution of Dinuclear Pentacoordinated Fe II and Mn II Complexes and of a Linear Tetranuclear Fe III Complex Obtained with the Ligand N , N , N ′, N ′‐Tetrakis[(6‐methyl‐2‐pyridyl)methyl]propane‐1,3‐diamine

Two neutral complexes [(L 6 3 4M)Fe 2 Cl 4 ]·2H 2 O·2CHCl 3 ( 1 ) and [(L 6 3 4M)Mn 2 Cl 4 ]·CH 3 CN ( 2 ) have been synthesized {L 6 3 4M = N , N , N′ , N′ ‐tetrakis[(6‐methyl‐2‐pyridyl)methyl]propane‐1,3‐diamine} and their molecular structures established by X‐ray crystallography. Both structures are similar, with each metal center in a trigonal‐bipyramidal environment. No magnetic coupling is observed between the metal centers. UV/Vis spectra and cyclic voltammograms were recorded in CH 2 Cl 2 and CH 3 CN solutions. Both complexes are stable in CH 2 Cl 2 , whereas only 2 is stable in CH 3 CN. On the contrary, 1 is in equilibrium with another Fe II species in CH 3 CN. When this last solution is aerated, monocrystals of the neutral linear tetranuclear complex [(L 6 3 4M)Fe 4 (μ‐O) 3 Cl 6 ]·2CH 3 CN ( 3 ) can be isolated. Its structure is unusual with two Fe III ions pentacoordinate and the two others tetracoordinate with only chloro ligands and oxo bridges. The magnetic properties reveal that two consecutive metal centers are strongly antiferromagnetically coupled. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)