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Chemistry
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(2,3,5,6-Tetrafluorophenolato)[5,10,15,20-tetrakis(4-methoxyphenyl)porphyrinato]iron(III) cyclohexane monosolvate

The title compound, [Fe(C6HF4O)(C48H36N4O4)]·C6H12, represents a five-coordinate iron(III) porphyrin complex in a square-pyramidal geometry with a tetrafluorophenolate anion as the axial ligand. The FeIII atom is displaced by 0.364 (2) Å from the 24-atom mean plane of the porphyrinate ring towards the tetrafluoro phenolate anion. The average Fe—N distance is 2.053 (2) Å and the Fe—O distance is 1.883 (2) Å. A porphyrin aryl H atom points in the general direction of the phenoxide ring. The mean plane separation between the 24-atom porphyrin planes of two adjacent porphyrin rings is ∼3.7 Å, and the lateral shift is ∼3.5 Å resu, ting in an Fe⋯Fe separation of 5.6167 (14) Å.

The title compound, [Fe(C 6 HF 4 O)(C 48 H 36 N 4 O 4 )]ÁC 6 H 12 , represents a five-coordinate iron(III) porphyrin complex in a square-pyramidal geometry with a tetrafluorophenolate anion as the axial ligand. The Fe III atom is displaced by 0.364 (2) Å from the 24-atom mean plane of the porphyrinate ring towards the tetrafluoro phenolate anion. The average Fe-N distance is 2.053 (2) Å and the Fe-O distance is 1.883 (2) Å . A porphyrin aryl H atom points in the general direction of the phenoxide ring. The mean plane separation between the 24-atom porphyrin planes of two adjacent porphyrin rings is $3.7 Å , and the lateral shift is $3.5 Å resu, ting in an FeÁ Á ÁFe separation of 5.6167 (14) Å .
The authors wish to thank the National Science Foundation (grant CHE-1213674) and the University of Oklahoma for funds to support this research and to acquire the diffractometer and computers used in this work.

Comment
Synthetic metalloporphyrins have been studied intensively due to their potential to act as models for heme enzymes in biological systems. Catalase is a heme enzyme that catalyzes the decomposition of hydrogen peroxide to water and oxygen (Nicholls et al., 2001). Heme catalase contains an active-site tyrosine, a phenolato type ligand, that binds to the heme iron center (Nicholls et al., 2001). A number of iron phenolate porphyrin complexes has been prepared and structurally characterized (Chaudhary et al., 2010, Ueyama et al., 1998, Kanamori et al., 2005. In this paper, we report the structure of (5,10,15,20-tetrakis(4-methoxyphenyl)porphyrinato)(tetrafluorophenolato)iron(III) with a cyclohexane monosolvate.
After stirring for 1 h, the color of the solution changed from green to red. The solution was reduced to 2 ml under reduced pressure, and 10 ml hexane was added. The resulting black precipitation was collected by filtration and dried under vacuum. A suitable prism-shaped crystal was grown by slow evaporation of a CH 2 Cl 2 -cyclohexane (1:1) solution of the complex at room temperature under N 2 .

Refinement
The positions of H atoms bonded to carbons were initially determined by geometry and were refined using a riding model. H atoms bonded to N atoms and O atoms were located on a difference map, and their positions were refined independently. Non-hydrogen atoms were refined with anisotropic displacement parameters. Hydrogen atom displacement parameters were set to 1.2 (1.5 for methyl) times the isotropic equivalent displacement parameters of the bonded atoms. Carbon-bound H atoms were placed in calculated positions (aromatic 0.95, ethyl 0.99, and methyl 0.95 Angstroms) and were refined using a riding model. The C-C bond distances in the cyclohexane were restrained to 1.52 Angstroms and the 1-3 C···C distances were restrained to be equal. Rigid-bond restraints were also applied to the anisotropic displacement parameters of the solvent carbons.

Figure 1
The molecular structure of (T(p-OMe)PP)Fe(OC 6 HF 4 ) . (C 6 H 12 ) with displacement ellipsoids drawn at the 35% probability level. H atoms are omitted for clarity.