Copper thioether chemistry: The synthesis and single crystal X-ray structures of [Cu2([18]aneS6)(NCMe)2](ClO4)2 and [Cu([9]aneS3)(AsPPh3)](ClO4)

Reaction of 18]aneS₆ with two molar equivalents of Cu(NCMe)₄](ClO₄) in CH₂Cl₂-MeCN affords the binuclear copper(I) complex Cu₂(18]aneS₆)(NCMe)₂](ClO₄)₂. The single crystal X-ray structure of the complex shows a centrosymmetric cation with two tetrahedral copper(I) centres each coordinated to three thioether S-donors of 18]aneS₆,Cu---S(1) = 2.3200(15), Cu---S(4) = 2.3415(16), Cu---S(7) = 2.3250(15) Å, and to one MeCN molecule, Cu---N(1) = 1.939(5) Å, to give an overall NS₃-donation at the metal centres. Additionally, S(7′) shows a long-range interaction, Cu …S(7′) = 3.318(2) Å thus distorting the coordination geometry of the metal ion towards trigonal bipyramidal. The metal-metal separation of 4.428(2) Å suggests that there is no significant interaction between the copper centres of the dimer. Reaction of 9]aneS₃ with one molar equivalent of Cu(NCMe)₄](ClO₄) in refluxing MeCN in the presence of ligands, L, affords the adducts Cu(9]aneS₃)L]⁺ (L = PPh₃, AsPh₃). The single crystal X-ray structure of the complex Cu(9]aneS₃)(AsPh₃)](ClO₄) shows tetrahedral AsS₃ coordination at copper(I) with 9]aneS₃ bound facially to the metal centre, Cu---S = 2.303(6), Cu---As = 2.322(4) Å.