Synthesis and characterization of tetraphenylporphyrin iron(III) complexes with substituted phenylcyanamide ligands Hossein Chiniforoshan a , Nasser Safari a, * , Jafar Mohammad Nezhad a , Hassan Hadadzadeh b , Amir H. Mahmoudkhani c a Department of Chemistry, Shahid Beheshti University, 1983963113, Evin, Tehran, Iran b Department of Chemistry, Sistan and Baluchestan University, 98135674, Zahedan, Iran c Department of Chemistry, University of Calgary, Alta., Canada T2N 1N4 Received 4 October 2005; received in revised form 1 January 2006; accepted 15 January 2006 Available online 3 March 2006 Abstract Several five coordinate complexes of [(TPP)Fe III (L)] in which TPP is the dianion of tetraphenylporphyrin and L is the monoanion of phenylcyanamide (pcyd) (1), 2,5-dichlorophenylcyanamide (2,5-Cl 2 pcyd) (2), 2,6-dichlorophenylcyanamide (2,6-Cl 2 pcyd) (3), and 2,3,4,6-tetrachlorophenylcyanamide (2,3,4,6-Cl 4 pcyd) (4) have been prepared by the reaction of [(TPP)Fe III Cl] with appropriate thallium salt of phenylcyanamide. Each of the complexes has been characterized by IR, UV–Vis and 1 H NMR spectroscopic data. Dark red- brown needles of [(TPP)Fe III (2,6-Cl 2 pcyd)] (C 51 H 31 Cl 2 FeN 6 Æ CHCl 3 ) crystallize in the triclinic system. The crystal structure of Fe(III) compound shows a slight distortion from square pyramidal coordination with the 2,6-dichlorophenylcyanamide anion in the axial posi- tion through nitrile nitrogen atom. Iron atom is 0.47(1) A ˚ out of plane of the porphyrin toward phenylcyanamide ligand. In non-coor- dinating solvents, such as benzene or chloroform, these complexes exhibit 1 H NMR spectra that are characteristic of high-spin (S = 5/2) species. The X-ray crystal structure parameters are also consistent with high-spin iron(III) complexes. The iron(III) phenylcyanamide complexes are not reactive toward molecular oxygen; however, these complexes react with HCl and produce TPPFe III Cl. Ó 2006 Elsevier B.V. All rights reserved. Keywords: Iron(III)phenylcyanamide; Tetraphenylporphyrin; X-ray; Paramagnetic 1 H NMR 1. Introduction Material engineering adopted to generate new electronic, magnetic and photonic devices is an active field [1–6]. To obtain high conductivity as well as strong effective magnetic coupling, expansion of the p-electronic molecular structure is one of the most important and promising approaches [7– 9]. For example, [TPPMn][tetracyanoethylene] Æ 2PhMe has shown to act as molecule-based magnet [10–13] and (2,5- dimethyl-N,N 0 -dicyanoquinone diimine) 2 Cu (DCNQI) has shown to exhibit extremely high conductivity of 500 000 S cm À1 at 3.5 K [14]. Crutchley [15] has investigated phenylcyanamide (ligands as analogue of DCNQI’s) in both neutral and anionic forms with metals, such as Ag I , Cu I , Cu II , Ni II , Pd II , Ru II , Co II ,W III and Mn II . Moreover, the biological and chemical importance of iron porphyrins make the nature of the metals–ligand linkage in these complexes of considerable interest [16– 19]. Numerous structural and physical characterizations of iron porphyrin with different axial groups have been reported during the last decades. One of the aims of these investigations is to couple large p-conjugated system of porphyrins into a large p-conjugate system in phenylcya- namide via bridged iron metals, which hybrid coordinate with organic p-stack systems, to produce building blocks for molecular materials. So, we here wish to report the first example of preparation and characterization of phenylcyanamide-ligated tetraphenylporphyrin iron(III) (L) complexes (1–4). It has become clear that 1 H NMR 0020-1693/$ - see front matter Ó 2006 Elsevier B.V. All rights reserved. doi:10.1016/j.ica.2006.01.015 * Corresponding author. Tel.: +98 21 2401765; fax: +98 21 2403041. E-mail address: n-safari@cc.sbu.ac.ir (N. Safari). www.elsevier.com/locate/ica Inorganica Chimica Acta 359 (2006) 2101–2106