Syntheses, Crystal Structure and Properties of Co(II), Fe(II) Complexes with Aza-donating Ligand

Four mononuclear Co(II) and Fe(II) complexes([Co(Ll)2] (ClO4)2· (CH3CN) (1), [Fe(Ll)2] (ClO4)2(H2O) (2), [Co(L2)] (ClO4)2(3), [Fe(L2)] (ClO4)2· 2H2O (4)(Ll=4′ -phenyl-2,2′:6′, 2″-terpyridine and L2 = N, N, N-tris(2-(2-pyridylmethylimino)ethyl)amine) were synthesized. The structures of complexes 1 and 3 were determined. Crystals of the two complexes belong to monoclinic space group and their cell parameters are: 1 a = 1. 0855(4) nm, b = 1. 6201(5) nm, c = 2. 5236(5) nm, β = 92. 63(2)°, V = 4. 433(1) nm3; 3 a = 2. 8351(8) nm, b = 1. 0670(3) nm, c = 1. 9255(5) nm, β = 101. 03(4)°, V = 5. 717(2) nm3. The redox potentials of complexes 2 and 4 are E = 0. 78 V and 0. 63 V, respectively and the maximal of their d-d transition absorption bands are located at 565 and 521 nm, respectively.