On the Use of the Bis(diiodine) Adduct of 1,4-Dimethylperhydro-1,4-diazepine-2,3-dithione (Me2dazdt) to Recover Liquid Mercury Producing [Hg(Me2dazdt)I2] in a One-Step Reaction

Diiodine adducts with cyclic dithio-oxamides, where complexing and oxidising properties coexist in the same molecule, have been shown to be powerful oxidising reagents towards selected metals. Here we describe the reaction of Me2dazdt-2I2 [Me2dazdt = 1,4-dimethyrperhydro-1,4-diazepine-2,3-dithione (1)] with highly toxic liquid mercury which gives the complex [Hg(Me2dazdt)I2] (2) in a one-step reaction. X-rays analysis of 2 shows that the HgII centre is coordinated by two sulfur atoms of the chelating ligand and by two iodine atoms in a distorted tetrahedral geometry. The molecule is asymmetric and crystallizes in the chiral space group P212121. In the unit cell only the M enantiomer is present [τ (S1-C1-C2-S2) = -61.1(5)°]