Iron(tetraporphyriinato) chloride is the

coordination complex A coordination complex consists of a central atom or ion, which is usually metallic and is called the ''coordination centre'', and a surrounding array of bound molecules or ions, that are in turn known as ''ligands'' or complexing agents. Many ...

with the formula Fe(TPP)Cl where TPP is the dianion ₄₄H₂₈N₄sup>2-. The compound forms blue microcrystals that dissolve in chlorinated solvent to give brown solutions. In terms of structure, the complex is five-coordinate with idealized C_4v point group symmetry. It is one of more common

transition metal porphyrin complexes 220px, A picket-fence porphyrin complex of Fe, with axial coordination sites occupied by methylimidazole (green) and dioxygen (R = amide groups). Transition metal porphyrin complexes are a family of coordination complexes of the conjugate base of ...

Synthesis and reactions

Fe(TPP)Cl is prepared by the reaction of

tetraphenylporphyrin Tetraphenylporphyrin, abbreviated TPP or H2TPP, is a synthetic heterocyclic compound that resembles naturally occurring porphyrins. Porphyrins are dyes and cofactors found in hemoglobin and cytochromes and are related to chlorophyll and vitamin ...

(H₂TPP) and ferrous chloride in the presence of air: :H₂TPP + FeCl₂ + 1/4 O₂ → Fe(TPP)Cl + HCl + 1/2 H₂O The chloride can be replaced with other halides and pseudohalides. Base gives the "mu-oxo dimer": :2 Fe(TPP)Cl + 2 NaOH → e(TPP)sub>2O + 2 NaCl + H₂O Most relevant to catalysis, the complex is easily reduced to give ferrous derivatives (L =

pyridine Pyridine is a basic heterocyclic organic compound with the chemical formula . It is structurally related to benzene, with one methine group replaced by a nitrogen atom. It is a highly flammable, weakly alkaline, water-miscible liquid with a d ...

imidazole Imidazole (ImH) is an organic compound with the formula C3N2H4. It is a white or colourless solid that is soluble in water, producing a mildly alkaline solution. In chemistry, it is an aromatic heterocycle, classified as a diazole Diazole refers ...

): :Fe(TPP)Cl + e- + 2 L → Fe(TPP)L₂ + Cl⁻ The complex is widely studied as a

catalyst Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recyc ...

.{{cite journal, doi=10.1021/jacs.9b02640, title=Mechanism of Catalytic O2 Reduction by Iron Tetraphenylporphyrin, year=2019, last1=Pegis, first1=M. L., last2=Martin, first2=D. J., last3=Wise, first3=C. F., last4=Brezny, first4=A. C., last5=Johnson, first5=S. I., last6=Johnson, first6=L. E., last7=Kumar, first7=N., last8=Raugei, first8=S., last9=Mayer, first9=J. M., journal=Journal of the American Chemical Society, volume=141, issue=20, pages=8315–8326, pmid=31042028, pmc=6684231

References

Chelating agents Tetrapyrroles Macrocycles Phenyl compounds