Synthesis and Stereochemistry of (Diamine)(2,9-dimethyl-4,7-diazadecane-2,9-dithiolato)cobalt(III) Complexes and Their Derivatives

Abstract

Abstract Several (diamine)(2,9-dimethyl-4,7-diazadecane-2,9-dithiolato)cobalt(III) complexes, [Co(SNNS)(diamine)]+ (diamine=1,2-ethanediamine and (R,R)-1,2-cyclohexanediamine), were prepared and characterized by the visible-UV absorption, circular dichroism(CD), and 13C NMR spectra. The above SNNS quadridentate ligand gave only the cis-β geometrical isomer, which was chromatographically separated into two diastereomers owing to the configurations of chiral nitrogen atoms. All the thiolato and the corresponding sulfinato complexes exhibited two CD bands of opposite signs in the Co(σ*)←S(σ) ligand-to-metal charge transfer band region. The sign pattern was found to be in connection with the absolute configurations of these complexes.