91741-69-4Relevant academic research and scientific papers
Nature of iron(I) and iron(0) tetraphenylporphyrin complexes. Synthesis and molecular structure of (dibenzo-18-crown-6)bis(tetrahydrofuran)sodium (meso-tetraphenylporphinato)ferrate and bis[tris(tetrahydrofuran)sodium] (meso-tetraphenylporphinato)ferrate
Mashiko, Toshio,Reed, Christopher A.,Haller, Kenneth J.,Scheidt, W. Robert
, p. 3192 - 3196 (2008/10/08)
A synthetic and structural investigation of the so-called iron(I) and iron(0) tetraphenylporphyrin complexes, [Fe(TPP)]- and [Fe(TPP)]2-, resolves a number of the existing ambiguities about their identity. [Fe(TPP)]- has a low-spin S = 1/2 state and is devoid of axial ligation at least in the solid state where it crystallizes as the purple, air-sensitive [Na(dibenzo-18-crown-6)(THF)2]+ salt. Crystal data: C72H68O8N4FeNa, monoclinic, space group P21/m, a = 12.796 (2) ?, b = 21.861 (4) ?, c = 12.108 (2) ?, β = 103.47 (1)°, Z = 2; Fe-Np(av) = 1.980 (6) ?. Analysis of the structural data requires inclusion of substantial iron(II) π-radical anion character in the previously favored iron(I) formulation. The green dianion [Fe(TPP)]2- has been isolated for the first time. It is diamagnetic and crystallizes in a tightly ion-paired structure where two [Na(tetrahydrofuran)3]+ cations interact with a pair of porphinato nitrogen atoms (Na?N = 2.784 (4), 2.825 (4) ?) above and below the porphyrin plane. The porphinato core bond lengths reveal considerable π-radical anion character. Crystal data: C68H76O6N4FeNa2, triclinic, space group P1, a = 11.877 (3) ?, b = 13.242 (3) ?, c = 11.242 (2) ?, α = 113.69 (2)°, β = 110.01 (2)°, γ = 77.55 (2)°, Z = 1; Fe-Np(av) = 1.968 (1) ?.
