Metal-betaine interactions. XVIII. Crystal structure of tetraaqua(trimethylammonioacetato)copper(III) sulfate trihydrate, [Cu(Me3NCH2CO2)(H2O)4](SO4)•3H2O

The title complex (C 5 H 25 CuNO 13 S) has been synthesized and characterized by single crystal X-ray analysis (R = 0.059 for 5934 observed hkl; MoK α data). The complex crystallizes in the triclinic space group P1 with a = 8.491(1), b = 8.942(2), c = 12.144(2) A, α = 101.17(2), β = 96.69(1), γ = 114.04(1)°, and Z = 2. The Cu(II) atom is in a distorted square pyramidal coordination environment, being surrounded by a carboxy oxygen atom of the betaine ligand [1.944(5) A] and three aqua oxygen atoms [Cu − O = 1.921(5) A ∼ 1.968(5) A] in the basal plane, with another aqua oxygen atom occupying the apical position [2.249(2) A]. Hydrogen bonds are formed by the aqua ligands, the lattice water molecules, the uncoordinated oxygen atom of the carboxy group, and the sulfate ion to generate a three-dimensional network