Preparation of N-bridged diiron phthalocyanines bearing bulky or small electron-withdrawing substituents

The synthesis of novel μ-nitrido diiron phthalocyanine with electron-withdrawing substituents is reported: μ-nitrido tetra-methylsulfonylphthalocyanine (13), μ-nitrido tetra-ethylsulfonylphthalocyanine (14), μ-nitrido tetra-adamantylsulfonylphthalocyanine (15), μ-nitrido tetra-cyclohexylsulfonylphthalocyanine (16). These complexes were characterized by ESI-MS, UV-vis, FT-IR and EPR techniques. The state of these complexes depends on the size of the substituents. Complexes 13 and 14 bearing small methylsulfonyl and ethylsulfonyl substituents are cationic ( PcFe IV NFe IV Pc ) + N 3 - complexes while complexes 15 and 16 with bulkier adamantylsulfonyl and cyclohexylsulfonyl substituents are formally neutral PcFe III NFe IV Pc complexes which can be represented as PcFe (+3.5) NFe (+3.5) Pc .