Further Studies on the Oxidation State of Iron in μ-Oxo Dimeric Phthalocyanine Complexes

Abstract

The reaction with sodium cyanide of the μ-oxo-bridged complex of tetra-4-tert-butyl-substituted iron phthalocyanine (form ‘690’) and that of the product of its treatment with organic bases such as Py, Im, etc. (form ‘627’) result in the formation of the same ferrous bis-cyanide complex Na 2 [ Pc t Fe II ( CN ) 2 ] which can be readily oxidized to the analogous ferric complex Na [ Pc t Fe III ( CN ) 2 ]. Form ‘690’ has been oxidized to the corresponding ferric μ-oxo complex (form ‘630’). Data for all μ-oxo-bridged complexes (chemical behavior; electronic, NMR, Mössbauer, X-ray photoelectron and ESR spectra; magnetic susceptibility) are discussed, and based on them, the following structures are proposed: ( HPc t Fe II ) 2 O (form ‘690’), H 2 [( LPc t Fe II ) 2 O ] (form ‘627’) and ( Pc t Fe III ) 2 O (form ‘630’).