Preparation and molecular structures of N,N-2,2'-dipicolyland N,N-3,3'-dipicolyldithiocarbamato metal complexes

New iron(III) and cobalt(III) complexes, [Fe(2,2'-dpdtc)3], [Fe(3,3'-dpdtc)3], [Co(2,2'-dpdtc)3], and [Co(3,3'-dpdtc)3] (dpdtc = dipicolyldithiocarbamate) have been synthesized and their molecular structures and spectroscopic properties determined. The 2,2'- and 3,3'-dpdtc ligands have four donors, S, S', N, and N'. These complexes are insoluble in water, but soluble in acidic solution. Crystal structures of these metal complexes reveal that the central metal ions have MS6 (M = Fe and Co) octahedral structures and all dipicolyl groups do not coordinate.