New Poly-Iron(II) Complexes of N4O Dinucleating Schiff Bases and Pseudohalides: Syntheses, Structures, and Magnetic and Mössbauer Properties
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- 作者：Athanassios K. Boudalis ; Juan-Modesto Clemente-Juan ; Franç ; oise Dahan ; and Jean-Pierre Tuchagues
- 刊名：Inorganic Chemistry
- 出版年：2004
- 出版时间：February 23, 2004
- 年：2004
- 卷：43
- 期：4
- 页码：1574 - 1586
- 全文大小：258K
- 年卷期：v.43,no.4(February 23, 2004)
- ISSN：1520-510X
文摘
Six dinuclear ferrous complexes including [Fe2(acpypentO)(O2CMe)(NCS)2] (1), [Fe2(acpypentO)(O2CMe)(NCSe)2](2), [Fe2(acpypentO)(NCO)3] (3), ([Fe2(acpybutO)(O2CMe)(NCS)2] (5), [Fe2(acpybutO)(O2CMe)(NCO)2] (6), and[Fe2(acpybutO)(O2CMe)(N3)2] (7), one tetranuclear (bis-dinuclear) ferrous compound, [Fe4(acpypentO)2(N3)6] (4),and one mononuclear ferrous compound, [Fe(acpybutOH)(NCS)2] (8), have been prepared, and their structuresand magnetic and Mössbauer properties have been studied (acpybutOH = 1,4-bis{[2-pyridyl(1-ethyl]imino)}butane-2-ol and acpypentOH = 1,5-bis{[2-pyridyl(1-ethyl]imino)}pentane-3-ol). The X-ray diffraction analyses yielded thefollowing results: 1 (C23H26Fe2N6O3S2, monoclinic, P21/n, a = 8.0380(7) Å, b = 12.4495(8) Å, c = 27.358(2) Å,
= 92.180(10)
, V = 2735.7(4) Å3, Z = 4) is a dinuclear species in which the unequivalent high-spin (HS) FeIIsites are bridged by the alkoxo oxygen atom of the symmetrical acpypentO- Schiff base and one syn-syn acetatoanion; 3 (C22H23Fe2N7O4, triclinic, P
, a = 8.4152(10) Å, b = 9.1350(10) Å, c = 17.666(2) Å, 
= 97.486(14), = 100.026(14), 
= 113.510(13), V = 1195.9(2) Å3, Z = 2) is a dinuclear species in which the unequivalentHS FeII sites are bridged by the alkoxo oxygen atom of the symmetrical acpypentO- Schiff base and one end-onNCO anion; 4-MeOH (C39H50Fe4N26O3, triclinic, P, a = 9.1246(11) Å, b = 10.2466(11) Å, c = 14.928(2) Å, =91.529(15), = 101.078(16), = 106.341(14), V = 1309.6(3) Å3, Z = 1) is a bis-dinuclear species in whichthe unequivalent HS FeII sites are bridged by the alkoxo oxygen atom of the symmetrical acpypentO- Schiff baseand one end-on N3- anion, and the symmetry related FeII sites are bridged by two end-on N3- anions; 8-MeOH(C21H26FeN6O2S2, triclinic, P, a = 8.7674(9) Å, b = 12.0938(13) Å, c = 12.2634(14) Å, = 106.685(14), =93.689(14), = 108.508(13), V = 1163.7(2) Å3, Z = 2) is a mononuclear species in which the octahedrallow-spin (LS) FeII site is in an N6 environment provided by the four N atoms of the protonated asymmetricalacpybutOH Schiff base and two thiocyanato anions. The Mössbauer spectra of all dinuclear species (1-3 and5-7), and of the bis-dinuclear compound 4, evidence two distinct HS FeII sites while the Mössbauer spectra of themononuclear compound 8 evidence a LS FeII site over the 80-300 K temperature range. The temperature dependenceof the magnetic susceptibility was fitted with J = -13.7 cm-1, D = -1.8 cm-1, and g = 2.096 for 1; J = 3.0 cm-1,D1 = 1.6 cm-1, E1 = -0.35 cm-1 (
1 = 0.22), D2 = - 12.2 cm-1, E2 = 1.1 cm-1 (2 = 0.09), and g = 2.136for 3; and J1 = - 0.09 cm-1, J2 = 15.9 cm-1, D1 = 5.7 cm-1, D2 = 12.1 cm-1, and g = 1.915 for 4. The natureof the ground state in 3 and 4 was confirmed by simulation of the magnetization curves at 2 and 5 K. The intradinuclearinteraction through the central Oalkoxo of the acpypentO- ligand and one pseudohalide bridges is ferromagnetic in3 (end-on cyanato) while it is very weakly antiferromagnetic in 4 (end-on azido). The interdinuclear interactionthrough two end-on azido bridges (4) is ferromagnetic as expected. In agreement with the symmetry of the two ironsites of complexes 3 and 4, the fits show that D2 (tetragonal pyramid) is larger than D1 (distorted trigonal bipyramid(3) or distorted octahedron (4)).
= 92.180(10), V = 2735.7(4) Å3, Z = 4) is a dinuclear species in which the unequivalent high-spin (HS) FeIIsites are bridged by the alkoxo oxygen atom of the symmetrical acpypentO- Schiff base and one syn-syn acetatoanion; 3 (C22H23Fe2N7O4, triclinic, P, a = 8.4152(10) Å, b = 9.1350(10) Å, c = 17.666(2) Å, = 97.486(14), = 100.026(14), = 113.510(13), V = 1195.9(2) Å3, Z = 2) is a dinuclear species in which the unequivalentHS FeII sites are bridged by the alkoxo oxygen atom of the symmetrical acpypentO- Schiff base and one end-onNCO anion; 4-MeOH (C39H50Fe4N26O3, triclinic, P, a = 9.1246(11) Å, b = 10.2466(11) Å, c = 14.928(2) Å, =91.529(15), = 101.078(16), = 106.341(14), V = 1309.6(3) Å3, Z = 1) is a bis-dinuclear species in whichthe unequivalent HS FeII sites are bridged by the alkoxo oxygen atom of the symmetrical acpypentO- Schiff baseand one end-on N3- anion, and the symmetry related FeII sites are bridged by two end-on N3- anions; 8-MeOH(C21H26FeN6O2S2, triclinic, P, a = 8.7674(9) Å, b = 12.0938(13) Å, c = 12.2634(14) Å, = 106.685(14), =93.689(14), = 108.508(13), V = 1163.7(2) Å3, Z = 2) is a mononuclear species in which the octahedrallow-spin (LS) FeII site is in an N6 environment provided by the four N atoms of the protonated asymmetricalacpybutOH Schiff base and two thiocyanato anions. The Mössbauer spectra of all dinuclear species (1-3 and5-7), and of the bis-dinuclear compound 4, evidence two distinct HS FeII sites while the Mössbauer spectra of themononuclear compound 8 evidence a LS FeII site over the 80-300 K temperature range. The temperature dependenceof the magnetic susceptibility was fitted with J = -13.7 cm-1, D = -1.8 cm-1, and g = 2.096 for 1; J = 3.0 cm-1,D1 = 1.6 cm-1, E1 = -0.35 cm-1 (1 = 0.22), D2 = - 12.2 cm-1, E2 = 1.1 cm-1 (2 = 0.09), and g = 2.136for 3; and J1 = - 0.09 cm-1, J2 = 15.9 cm-1, D1 = 5.7 cm-1, D2 = 12.1 cm-1, and g = 1.915 for 4. The natureof the ground state in 3 and 4 was confirmed by simulation of the magnetization curves at 2 and 5 K. The intradinuclearinteraction through the central Oalkoxo of the acpypentO- ligand and one pseudohalide bridges is ferromagnetic in3 (end-on cyanato) while it is very weakly antiferromagnetic in 4 (end-on azido). The interdinuclear interactionthrough two end-on azido bridges (4) is ferromagnetic as expected. In agreement with the symmetry of the two ironsites of complexes 3 and 4, the fits show that D2 (tetragonal pyramid) is larger than D1 (distorted trigonal bipyramid(3) or distorted octahedron (4)).