CONSPECTUS

No abstract

No abstract

After a brief reflection on the important discoveries in main group chemistry during the past century, this article provides some suggestions concerning areas in which studies of s-and p-block element compounds are likely to have a major impact on the discipline of chemistry and upon society in general in the context of significant advances that have been made in the last decade. These areas range from fundamental to applied aspects of the subject. In the former category, novel aspects of chemical bonding and new reagents for synthetic applications are considered. From a more practical perspective alternative energy sources (especially hydrogen storage), new materials (notably nanomaterials and chemical sensors), catalysis (in the context of green chemistry), and medicinal chemistry (both diagnostic and therapeutic applications) are discussed.

No abstract

Two-electron oxidation of the [C(PPh(2)S)(2)](2-) dianion with iodine afforded an unexpected mixture of a dimeric Li-I carbenoid [(Et(2)O)(mu-Li)][(mu(4)-Li){IC(PPh(2)S)(2)}(2)] and a novel, unsaturated six-membered C(2)P(2)S(2) ring in [(SPh(2)P)(2)C(2)(PPh(2))(2)S(2)].

Metathetical reactions between TMEDA.Li[(H)C(PPh(2)Se)(2)] and MCl(2) (M = Hg, Sn, Te) in a 2 : 1 molar ratio afforded the homoleptic complexes, {M[(H)C(PPh(2)Se)(2)](2)}, as intermediates which undergo a surprising selenium/hydrogen exchange at the carbon centre to yield the dianionic triseleno ligand in {M(n)[(Se)C(PPh(2)Se)(2)](2)} (n = 1, M = Sn, Te; n = 2, M = Hg).

The reactions of triethylphosphine telluride with SO2Cl2 or I2 produced the first structurally characterized tellurium-containing tertiary phosphine chalcogen dihalides, Et3PTeCl2 and Et3PTeI2, respectively, in good yields. The corresponding dibromide, Et3PTeBr2, was obtained by an in situ reaction between Et3PTeCl2 and two equivalents of Me3SiBr. This series of compounds has been characterized in the solid state by X-ray structural analyses and in solution by multinuclear NMR spectra. The structures of Et3PTeX2(X = Cl, Br, I) all show a T-shaped geometry around tellurium with weak Te...halogen interactions giving rise to centrosymmetric dimers. NMR data indicate that Et3PTeI2 exhibits the weakest P-Te bond in solution. The ionic complexes, [(Et3PO)2H]2[Te2I6] and [(Et3PO)2H]2[TeI4], were isolated from THF solutions of Et3PTeI2 and characterized by X-ray structural determinations.