Dimerization of new T-shaped hypervalent organotellurium(II) dihalides: Synthesis and structural characterization of (PyH)[mesTeIX] (Py = pyridine; mes = mesityl; X =Cl, Br, I)

Abstract

[mesTe]2 reacts with iodine in toluene and further with (C 5H6N)+X- (X = I, Br, Cl) to give (PyH)[mesTeI2] (1), (PyH)-[mesTeIBr] (2) and (PyH)[mesTeICl] (3). The anionic fragments [(mes)TeI2] and [(mes)TelBr] of 1 and 2 are assembled as dimers by reciprocal, secondary Te⋯ interactions, linked also to the pyridinium cations through μ-NH⋯X bonding. The anion [(mes)TeICl]- (3) do not interact with neighboring anionic moieties, achieving also secondary NH⋯Cl bonding toward the pyridinium cation. The dimerization ability -with attaining of additional interionic hydrogen bridges -of 1 and 2 allow them to be viewed as partially "molecular" and as hypervalent compounds of TeII, for which the observed linearity of the I-Te-X system and the similarity of the Te-X bond distances are expected. © 2006 Wiley-VCH Verlag GmbH & Co. KGaA.