Te-X bonds

Recent progress on the use of hypervalent iodine reagents for the construction of carbon-het-eroatom (N, O, P, S, Se, Te, X) bonds is reviewed. Reactions of aryl-A3-iodanes with organic substrates are considered first and are loosely organized by functional group, separate sections being devoted to carbon-azide and carbon-fluorine bond formation. Arylations and alkenyla-tions of nucleophilic species with diaryliodonium and alkenyl(aryl)iodonium salts, and a variety of transformations of alkynyl(aryl)iodonium salts with heteroatom nucleophiles are then detailed. Finally, the use of sulfonyliminoiodanes as aziridination and amidation reagents, and reactions of iodonium enolates formally derived from monoketones are summarized. [Pg.137]

It is interesting to note that the coordination environment in the halidotellurate anions is an almost regular octahedron in apparent violation of the VSEPR rules for a 14 electron AXgE system. It has been suggested that the lone electron pair of tellurium resides in the stereochemically inactive 6s orbital and the six Te-X bonds form three pairs of 3c-4e bonds involving the three 6p orbitals (for a more detailed discussion, see Ref 81). [Pg.4792]

In the case of the complexes Et3P-TeX2, X = halogen, dimeric units units are formed which are held together by weak Te-X bonds (9.688a). Associated units of this kind are not uncommon, and occur with both Se and Te derivatives, for example, Ph3PSe(Ph)Br (9.688b) [11,35-42]. [Pg.816]

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