title: Synthesis, Reactivity, and Structural Characterization of the Nonclassical [MTe(7)](n)()(-) Anions (M = Ag, Au, n = 3; M = Hg, n = 2).
abstract: Several tellurometalates of the general formula [MTe(7)](n)()(-) (n = 2, 3) have been isolated as salts of organic cations by reaction of suitable metal sources with polytelluride solutions in DMF. The [HgTe(7)](2)(-) anion has the same structure in both the NEt(4)(+) and the PPh(4)(+) salts except for a minor change in the ligand conformation. The [AgTe(7)](3)(-) and [HgTe(7)](2)(-) anions contain metal atoms coordinated in trigonal-planar fashion to eta(3)-Te(7)(4)(-) ligands. The central Te atom of an eta(3)-Te(7)(4)(-) ligand is coordinated to the metal atom and to two Te atoms in a "T"-shaped geometry consistent with a hypervalent 10 e(-) center. The planar [AuTe(7)](3)(-) anion may best be described as possessing a square-planar Au(III) atom coordinated to an eta(3)-Te(5)(4)(-) ligand and to an eta(1)-Te(2)(2)(-) ligand. The reaction of [NEt(4)](n)()[MTe(7)] (M = Hg, n = 2; M = Au, n = 3) with the activated acetylene dimethyl acetylenedicarboxylate (DMAD) has yielded the products [NEt(4)](n)()[M(Te(2)C(2)(COOCH(3))(2))(2)] (M = Hg, n = 2; M = Au, n = 1). The metal atoms are coordinated to two Te(COOCH(3))C=C(COOCH(3))Te(2)(-) ligands, for M = Hg in a distorted tetrahedral fashion and for M = Au in a square-planar fashion.
authors.affiliation: Department of Chemistry, Northwestern University, Evanston, Illinois 60208-3113.
authors.forename: Donna M.
authors.initials: DM
authors.lastname: Smith
authors.forename: Lisa C.
authors.initials: LC
authors.lastname: Roof
authors.forename: Mohammad A.
authors.initials: MA
authors.lastname: Ansari
authors.forename: Jonathan M.
authors.initials: JM
authors.lastname: McConnachie
authors.forename: John C.
authors.initials: JC
authors.lastname: Bollinger
authors.forename: Michael A.
authors.initials: MA
authors.lastname: Pell
authors.forename: Robert J.
authors.initials: RJ
authors.lastname: Salm
authors.forename: James A.
authors.initials: JA
authors.lastname: Ibers