Gilles Lagrange

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].