The Oxidation Products of Tetracyanoferrate(II) Chelates with Optically Active 1,2-Diamines: Tetracyano(1,2-diamine)ferrate(III)s and Tetracyano(1,2-diimine)ferrate(II)s

Abstract

Abstract Optically active diamagnetic title complexes were oxidized with hydrogen peroxide under acidic and basic aqueous conditions. The corresponding low-spin tetracyano(diamine)ferrate(III) complexes with (R)-1,2-propanediamine, (1R,2R)-1,2-cyclopentanediamine, and (1R,2R)-1,2-cyclohexanediamine as diamines formed under acidic conditions and were characterized with several spectral measurements including the CD spectra. Each CD spectrum showed a moderate positive Cotton effect at ca. 24700 cm−1 and was assigned to a d-d transition. However a ligand oxidation took place, yielding tetracyano(1,2-diimine)ferrate(II) complexes under neutral and basic conditions; their electronic and 1H- and 13C-NMR spectra are also reported.