Metal chloride compounds of chelating imidazolethioether ligands. Crystal structures of dichloro-(1,6-bis(5-methyl-4-imidazolyl)-2,5-dithiahexane)copper(II) and {chloro-(1,6-bis(5-methyl-4-imidazolyl)-2,5-dithiahexane)copper(II)} chloride dihydrate

Abstract

The synthesis and spectroscopic properties of the cobalt, nickel, copper and zinc chlorides of the ligands 1,6-bis(5-methyl-4-imidazolyl)-2,5-dithia-hexane (abbreviated bidhx) and 1,6-bis(4(5)-imidazolyl)-2,5-dithiahexane (abbreviated bdhdhx) are described. The compound Cu(bidhx)Cl 2 (A) crystallizes in the orthorhombic space group Pbca with a = 17.917(2), b = 14.502(4), c = 12.905(2) Å, V = 33536.15 Å 3, D x = 1.651 g cm 3 for Z = 8. The compound [Cu(bidhx)Cl]Cl · 2H 2O (B) crystallizes in the triclinic space group P-1 with a = 8.270(5), b = 10.890(5), c = 11.478(5) Å, α = 87.52(4)°, β = 76.93(5)°, γ = 71.52(4)°, V = 954.5 Å 3, D x = 1.576 g cm 3 for Z = 2. Both structures were solved by heavy atom techniques and refined by least-squares methods to residual R w values of 0.037 (A) and 0.034 (B). The coordination geometry of the copper ion in compound (A) is a compressed octahedron with the two imidazole nitrogens along the main axis at 1.94 and 1.95 Å, and both chloride anions and the two thioether sulfur atoms at relatively large distances in the equatorial plane (CuCl 2.39 and 2.56 Å, CuS 2.62 and 2.81 Å). The copper ion in compound (B) is in a distorted trigonal bipyramid, formed by the two imidazole nitrogen atoms in the axial position (1.94 and 1.95 Å), and the two thioether sulfurs and one chloride ion in the equatorial plane (CuS 2.53 and 2.46 Å, CuCl 2.29 Å). The nickel and cobalt bidhx chlorides and the copper and nickel bhdhx chlorides are isostructural with compound A.