Crystal structure of trans-di­aqua­(3,10-dimethyl-1,3,5,8,10,12-hexa­aza­cyclo­tetra­deca­ne)copper(II) pamoate

The asymmetric unit of the title compound, trans-di­aqua­(3,10-dimethyl-1,3,5,8,10,12-hexa­aza­cyclo­tetra­decane-κ(4) N (1),N (5),N (8),N (12))copper(II) 4,4′-methyl­ene­bis(3-hy­droxy­naphthalene-2-carboxyl­ate), [Cu(C(10)H(26)N(6))(H(2)O)(2)](C(23)H(14)O(6)) {[Cu(L)(H(2)O)(2)](pam), where L = 3,10-dimethyl-1,3,5,8,10,12-hexa­aza­cyclo­tetra­decane and pam = dianion of pamoic acid} consists of two independent halves of the [Cu(L)(H(2)O)(2)](2+) cation and one di­carboxyl­ate anion. The Cu(II) atoms, lying on inversion centres, are coordinated by the four secondary N atoms of the macrocyclic ligands and the mutually trans O atoms of the water mol­ecules in a tetra­gonally elongated octa­hedral geometry. The average equatorial Cu—N bond length is significantly shorter than the average axial Cu—O bond length [2.007 (10) and 2.486 (18) Å, respectively]. The macrocyclic ligand in the complex cations adopts the most energetically stable trans-III conformation. The complex cations and anions are connected via hydrogen-bonding inter­actions between the N—H groups of the macrocycles and the O—H groups of coordinated water mol­ecules as the proton donors and the O atoms of the carboxyl­ate as the proton acceptors into layers lying parallel to the (1[Image: see text]1) plane.