N.m.r. studies of some dimethylthallium compounds

The proton n.m.r. spectra of (Me2TlX)2(X = OEt, OBu-t, OPh, SMe, SO2Me, C5H5 and CCPh) have been observed. The methyl doublet in the dimethylthallium ethoxide spectra shows an unusual variation with temperature: tentative explanations are discussed. The variation of 2J(H…Tl) with mol ratio in mixtures of trimethylthallium and trimethylamine shows that this coupling constant has the same sign in Me3Tl and Me3Tl.NMe3.