Panayotis Cocolios

Pentacoordinate iron(III) porphyrin carboxylates: Synthesis, physicochemical characteristics and x-ray crystal structure of acetato(5, 10, 15, 20-tetraparatolylporphyrinato) iron(III)

Abstract Carboxylatoiron(III) porphyrins have been synthesised by the action of carboxylic acids on the [(por)Fe]2O dimers. 1H NMR and ESR data of the isolated products are in accordance with pentacoordinate high spin 5/2 ferric complexes, the iron atom being displaced out of the plane of the porphyrin ligand. IR spectra show ν(CO) and ν(CO) bands separated by 356–409 cm−1. The magnitude of this separation suggests coordination between the metal centre and the carboxylate group via one oxygen atom. Magnetic susceptibility measurements from 5 to 120 K lead to the value of μ = 5.88 B.M.. The X-ray structure of acetato (5, 10, 15, 20-tetra p-tolyporphyrinato) iron(III) confirms the above deductions. (tp MePP) Fe(CO2CH3). 0.5 CH3COOH crystallises in the I2/c space group with unit cell parameters a = 24.464(8), b = 9.332(3), c = 37.174(4) A, β = 90.49(2)°, V = 8485 A3, Dc = 1.27 g · cm−3 and Z = 8. The crystal structure was refined to a conventional R(F) = 0.0584 and Rw(F) = 0.0653 for 5132 unique reflections with F0 > 3σ(F0). The iron atom is pentacoordinated by the four nitrogen atoms and one oxygen atom of the acetate group. It lies at 0.520(1) A out of the porphinato plane and 0.485(1) A out of the four nitrogen plane. The FeO bond length is 1.898(4) A.

Synthesis and physicochemical characteristics of alkane (or arene)-thio-, -sulphinato-, and -sulphonato-indium(III) porphyrins. Crystal structure of methanesulphonato(5,10,15,20-tetraphenylporphyrinato)indium(III)

Indium(III) porphyrins containing metal–sulphur bonds [InL(SR)](L = porphyrinate, R = alkyl or aryl) are reported. The photochemical oxidation of these leads to the corresponding sulphinatoindium(III) porphyrins [InL(SO2R)]. The insertion of sulphur dioxide between the indium atom and the alkyl or aryl group of [InL(R)] also gives rise to the sulphinato-compounds. The latter can easily be oxidised to the corresponding sulphonato-complexes. The crystal structure of the title compound [In(tpp)(SO3CH3)]·2C2H4Cl2 has been determined by X-ray diffraction methods. Crystals are triclinic, space group P, with a= 13.027(2), b= 13.284(2), c= 14.029(2)A, α= 68.82(2)°, β= 85.31(2)°, γ= 88.13(2)°, and Z= 2. The structure has been solved by Patterson and Fourier methods and refined by full-matrix least-squares calculations to R= 0.063. This complex crystallises as a one-dimensional polymer, parallel to the c axis. The indium atom lies rigorously in the four-nitrogen plane and the structure may be described as the close packing of [In(tpp)]+ and [SO3CH3]– ions. A high-resolution n.m.r. study shows that this structure is destroyed in solution at low concentrations.

Alkane (or arene)-sulphinato and -sulphonato-iron(III) porphyrins: synthesis and physicochemical properties; crystal structure of benzenesulphinato(5,10,15,20-tetraphenylporphyrinato)iron(III)

Sulphinatoiron(III) porphyrins [FeL(SO2R)](L = porphyrinate, R = alkyl or aryl) have been prepared by the insertion reaction of sulphur dioxide into the Fe–C σ bond of alkyl(or aryl)iron (III) porphyrins [FeLR]. The obtained products are easily oxidised by molecular oxygen to the corresponding sulphonate derivatives, also generated by acid hydrolysis of the Fe–O bonds of the µ-oxo-dimers [(FeL)2O] by the appropriate sulphonic acid. The stereochemistry of the metal centre has been established by 1H n.m.r., e.s.r., and i.r. measurements and confirmed by the crystal structure determination of the title compound by X-ray diffraction methods. The crystals are triclinic, space group P1, with a= 11.01 (2), b= 11.09(1), c= 11.37(2)A, α= 107.2(1), β= 107.9(1), γ= 110.2(1)°, and Z= 1. The structure has been solved from diffractometer data by direct and Fourier methods and refined by full-matrix least-squares calculations to R= 0.097 for 1 901 reflections. The iron atom is five-co-ordinated by the four nitrogen atoms of the porphyrin and one oxygen atom of the sulphinato-group [Fe–O 1.92(1)A].