Mechanism of the reaction of iron(III) dithiocarbamates with iodine

Abstract

The reaction between [Fe(S₂CNR₂)₃](R = CH₂Ph or Et, NR₂= morpholino) and iodine in methylene chloride has been studied by means of spectrophotometric methods. Intermediate and product spectroscopic analyses have led to the following reaction scheme: [Fe(S₂CNR₂)₃]+ I₂ [graphic omitted] [Fe(S₂CNR₂)₃]·I₂ [graphic omitted] [Fe(S₂CNR₂)₃]⁺+ I₃^– [graphic omitted] [Fe(S₂CNR₂)₂I]+½(S₂CNR₂)₂+ I₂ A fast equilibrium reaction to give a 1 : 1 adduct [Fe(S₂CNR₂)₃]·l₂ precedes oxidation of iron(III) to iron(IV) to give [Fe(S₂CNR₂)₃]l_3′ which is in equilibrium with the five-co-ordinated [Fe(S₂CNR₂)₂l], tetra-alkylthiuram disulphide, and iodine.