Diselenolate- and ditellurolate-carborane gold complexes

Abstract

Gold complexes with selenolate and tellurolate carborane ligands [E₂C₂B₁₀H₁₀]²⁻ (E = Se, Te) have been synthesized by reaction of a freshly prepared solution of [1,2-(LiE)₂C₂B₁₀H₁₀] (E = Se, Te) with [AuClL] (L = PPh₃, PPh₂Me, PPh₂py) in a 1 : 2 molar ratio or [Au₂Cl₂(P∼P)] [P∼P = dppf, 1,1′-bis(diphenylphosphano)ferrocene; dppe, 1,2-bis(diphenylphosphano)ethane; dppc, 1,2-bis(diphenylphosphano)-o-carborane] in a 1 : 1 molar ratio affording complexes [Au₂(μ-1,2-E₂C₂B₁₀H₁₀)L₂] or [Au₂(μ-1,2-E₂C₂B₁₀H₁₀)(P∼P)], respectively. The gold(III) species PPN[Au(E₂C₂B₁₀H₁₀)₂] (PPN = bis(triphenylphosphano)iminium) have been afforded by reaction of PPN[AuCl₄] with [1,2-(LiE)₂C₂B₁₀H₁₀]. Complex [Au₄(μ-1,2-Se₂C₂B₁₀H₁₀)₂(μ-dppc)₂] displays a tetranuclear structure, different from the dinuclear cyclic arrangement proposed for other complexes with diphosphanes of [Au₂(μ-1,2-Se₂C₂B₁₀H₁₀)(P∼P)] stoichiometry.