Molecular structure, magnetic properties, cyclic voltammetry of the low-spin iron(III) Bis(4-ethylaniline) complex with the para-chloro substituted meso-tetraphenylporphyrin

Abstract In this study, the preparation of a new iron(III) hexacoordinated metalloporphyrin namely the bis(4-ethylaniline){ meso -tetra( para -chlorophenyl)porphyrinato}iron(III) triflate hemi-4-ethylaniline monohydrate with the formula [Fe III (TClPP)(PhEtNH 2 ) 2 ]SO 3 CF 3 • 1/2PhEtNH 2 • H 2 O (I) was reported. This is the first example of an iron(III) metalloporphyrin bis(primary amine) with an aryl group adjacent to the amino group. This species was characterized by elemental, spectroscopic analysis including UV–visible and IR data, cyclic voltammetry, SQUID measurements and X-ray molecular structure. The mean equatorial distance between the iron(III) and the nitrogens of the porphyrin is appropriate for a low-spin (S = 1/2) iron(III) porphyrin complex. The magnetic data confirm the low-spin state of our ferric derivative while the cyclic voltammetry indicates a shift of the half potential E 1/2 [Fe(III)/Fe(II)] of complex ( I ) toward more negative value. In the crystal of ( I) , the [Fe III (TClPP)(PhEtNH 2 ) 2 ] + ions, the triflate counterions and the water molecules are involved in a number of O __ H⋯O, N __ H⋯O, C–H⋯O and C __ H⋯π intermolecular interactions forming a three-dimension network.