Synthesis and characterization of N,N ',C-bound organotellurium(IV) and organomercury(II) derivatives

We report the synthesis and characterization of the first examples of organotellurium (IV)/organomercury(II) derivatives of N,N',C-chelating aryldiamine ligand, 2-{Me2NCH2CH2N(Me)CH2}C6H4Br (20). The dichalcogenides, [2-{Me2NCH2CH2N(Me)CH2}C6H4Se](2) (24) and [2-{Me2NCH2CH2N(Me)CH2}C6H4Te](2) (25), were prepared by treatment of the corresponding Grignard reagent (21)/organolithium reagent (22) in THF with selenium or tellurium, respectively. Compounds [2-{Me2NCH2CH2N(Me)CH2}C6H4](2)Se (26) and [2-{Me2NCH2CH2N(Me)CH2}C6H4]Te(S2CN(CH2CH3)(2) (27) were synthesized by the reaction of 21/22 with Se(dtc)(2) in 2:1 or Te(dtc)(2) (dtc = diethyldithiacarbamate) in 1:1 ratio at room temperature. In contrast, the reaction of 21 with TeI2 afforded an unexpected protonated derivative, [2-{(Me2NCH2CH2N(Me)CH2}C6H4TeI](+)(I)(-) (28a). Similarly, the halogenation reactions of 25 with chlorine gas or a solution of bromine in THF afforded protonated derivatives, [2-{(Me2NCH2CH2N(Me)CH2}C6H4TeCl3](+) (Cl)(-) (29a) and [2-{(Me2NCH2CH2N(Me)CH2}C6H4TeBr3](+) (Br) (-) (30a), respectively. The organomercury precursors; 2-{Me2NCH2CH2N(Me)CH2}C6H4HgCl0.54/Br-0.46 (31) and 2-{Me2NCH2CH2N(Me)CH2}C6H4HgBr (32), were obtained by the reaction of 21 with HgCl2 and HgBr2 in dry THF, respectively. The metathetical reaction of 3lwith silver azide afforded air- and moisture-stable organomercury azide, 2-{Me2NCH2CH2N(Me)CH2}C6H4HgN3 (33) in 87% yield. The transmetallation reaction of 31 with TeBr4 led to isolation of known o-formylphenyltellurenyl bromide. All the derivatives were characterized by various spectroscopic techniques such as H-1, C-13, Se-77, Te-125, Hg-199 NMR spectroscopy, elemental analysis, ES-MS and HAMS studies.