Synthesis and crystal structure of tris(N-p-methylphenyl-3-hydroxy-2-ethyl-4-pyridinonato)iron(III)

The complex [Fe(C14H14NO2)(3)]. 2H(2)O has been prepared by reaction of N-p-methylphenyl-3-hydroxy-2-ethyl-4-pyridinone with FeCl3. 6H(2)O. A single-crystal X-ray study shows that the iron atoms lie in a trigonally distorted octahedral environment coordinated to the hydroxy and ketone oxygen atoms of three ligands in the mer configuration M-r = 773.57(C42H46N3O8Fe). The crystal is hexagonal with space group P(3) over bar 1c; a = 15.943(2), c = 17.612(4)Angstrom, V = 3877.0(12)Angstrom (3), Z = 4, D-c = 1.325 g/cm(3), mu = 0.445 mm(-1), F(000) = 1634, R = 0.0446, wR = 0.1154 for 3085 reflections with I>2 sigma (I). The bond lengths from iron to oxygens are 1.980(1)Angstrom for the ketone oxygens and 2.071(1)Angstrom for the hydroxy oxygens. The molecule exhibits the expected propeller shape, and the angle of the trigonal twist is 48.37 degrees. The dihedral angles are 0.5(2) between chelate ring plane and pyridine ring plane and 71.31(7)degrees between pyridine ring plane and benzene ring plane. The solvent H2O(O(3) and O(4)) molecules are linked with O(2) and O(1) by hydrogen bonds with bond lengths 2.900(1) and 2.999(1)Angstrom, respectively.