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Complexes of o-phenylenediamine with iron (11) halides have been prepared and characterized by infrared, electronic, and Mossbauer spectroscopy and magnetic susceptibility measurements. Compounds having two, three, four, and six o-phenylenediamine ligands per iron have been isolated. The complexes are all high spin. The infrared data indicate that some of the complexes involve chelated ligands and others unidentate ligands. 0-PHENYLENEDIAMINE (opda) can function as a bidentate or unidentate ligand in metal complexes. Hieber et aZ.l and Barvinok and Bukhareva prepared complexes of the ligand with CuII, CdII, CoII, NiII, and ZnII.More recently, a series of Ni(I1) complexes having one, two, three, four, and six o-phenylenediamine molecules have been reported.3~4 These complexes have magnetic and spectral properties characteristic of octahedral NiII. Using the N-H and C-N stretching frequencies as indicators, the type of co-ordination for each complex was determined. The hexakis-complex was proposed to have six unidentate ligands. The tetrakis-complexes were considered to have two chelated and two unidentate o-phenylenediamine molecules in a transconfiguration. The bis-and tris-species were suggested to have only chelated ligands with the bis-complex also having two anions co-ordinated in axial positions. The conclusions have to some extent been substantiated by electronic spectral data.3-5 Duff * has also reported the preparation and spectroscopic data on some CU(II) and CO(II) complexes.Previous reports of complexes of iron with o-phenylenediamine and other aniline type ligands are very scarce. Ahuja et al. have reported 6-8 a large number of aniline and substituted aniline complexes of other firstrow transition metals but specifically note 6 the difficulty of preparing the iron analogues. Hieber has reported that reaction of o-phenylenediamine with Fe(CO), yields a complex [Fe(opda),] [Fe,(CO),,].It is the purpose of this article to report the preparation and characterization of ten complexes of o-phenylenediamine with FelI halides. EXPERIMENTALMaterials.-The anhydrous iron(I1) salts used in the preparation of the complexes were used as obtained from Alpha Inorganic. The o-phenylenediamine used was purified by dissolving in hot water, adding activated charcoal, filtering, and cooling to effect crystallization of the ligand.Preparation of Complexes.-The preparations of the complexes in most cases followed the same general procedure. The appropriate iron salt (anhydrous) was dissolved in ca. 25 ml. of ethanol and filtered to remove insoluble impurities.

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