In:
Journal of Porphyrins and Phthalocyanines, World Scientific Pub Co Pte Ltd, Vol. 20, No. 01n04 ( 2016-01), p. 254-264
Abstract:
The reaction of [Fe(TMP)(OClO[Formula: see text]], where TMP is the dianion of tetramesitylporphyrin, with a combination of a strong [Formula: see text] -acceptor ligand and a [Formula: see text]-donating imidazole can lead to the preparation of mixed-ligand complexes [Fe(Porph)(4-CNPy)(L)] [Formula: see text] where L is imidazole itself or 1-acetylimidazole and 4-cyanopyridine is the strong [Formula: see text] acceptor ligand. The stability of the new mixed-ligand pair is the presumed result of synergic bonding between the two axial ligands. The molecular structure and other characterization of the new mixed axial ligand complex, [Fe(TMP)(4-CNPy)(HIm)]ClO 4 is described. The axial ligands have a relative perpendicular arrangement with Fe–N(imidazole) = 1.945 Å and Fe–N(pyridine) = 2.021 Å. The average equatorial Fe–N[Formula: see text] distance is 1.963 Å, which is consistent with the S 4 -ruffled TMP core. Despite the relative perpendicular arrangement of axial ligands, the EPR spectrum of the complex is a rhombic signal and not a large g max signal. The EPR g-values are [Formula: see text] 3.05, [Formula: see text] 2.07, and [Formula: see text] 1.22. A quadrupole doublet was seen in the Mössbauer spectrum with an isomer shift of 0.197 mm/s and quadrupole splitting of 1.935 mm/s. Two crystalline forms of [Fe(TMP)(4-CNPy)(HIm)] ClO 4 have been characterized; the two forms differ only in the solvent content of the lattice. Crystal data for form A: [Formula: see text] 15.432 (12) Å, [Formula: see text] 20.696 (2) Å, [Formula: see text] 19.970 (5) Å, and [Formula: see text] 99.256 (14)[Formula: see text], monoclinic, space group P2 1 /n, V [Formula: see text] 6295 (2) Å 3 , Z [Formula: see text] 4, formula FeCl 3 O 4 N 8 C[Formula: see text]H[Formula: see text] , 8397 observed data, [Formula: see text] 0.086, [Formula: see text] 0.210, refinement on [Formula: see text]. Crystal data for form B: [Formula: see text] 15.267 (3) Å, [Formula: see text]20.377 (6) Å, [Formula: see text] 19.670 (4) Å, and [Formula: see text] 98.14 (1)[Formula: see text] , monoclinic, space group P[Formula: see text]/n, V = 6058 (4) Å 3 , Z = 4, formula C[Formula: see text]H[Formula: see text] Cl[Formula: see text]FeN 8 O 4 , 5464 observed data, [Formula: see text] 0.096, [Formula: see text] 0.112, refinement on F.
Type of Medium:
Online Resource
ISSN:
1088-4246
,
1099-1409
DOI:
10.1142/S1088424616500206
Language:
English
Publisher:
World Scientific Pub Co Pte Ltd
Publication Date:
2016
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