Synthesis, properties, and structure of the complexes of divalent metals with 1-hydroxyethane-1,1-diphosphonic acid (H4L), [(HOCH2CH2)(3)NH][M-II(H2.5L)(2)(H2O)(2)]center dot 5H(2)O. Crystal structure of triethanolammonium Bis(1-hydroxyethane-1,1-diphosphonato)diaquacuprate(II) pentahydrate

The synthesis of a series of the [(HOCH2CH2)(3)NH] [M-II(H2.5L)(2)(H2O)(2)] . 5H(2)O (M-II = Cu, Zn, Mg, Mn, Co, and Ni) compounds is reported. All cr ystals are isostructural. X-ray structural analysis is carried out for the copper(II) complex. The complexed anion has the cis structure. The coordina tion polyhedron of the metal atom is a prolate tetragonal bipyramid (4 + 2) , with one of the four O(L) atoms and one of the two O(w) atoms of the H2O molecules occupying axial positions. The bond lengths are Cu-O(eq) 1.982-1. 996 Angstrom (L) and 1.986 Angstrom (H2O) and Cu-O(ax) 2.428 Angstrom (L) a nd 2.311 Angstrom (H2O). The anionic complexes, the triethanolammonium cati ons, and H2O molecules of crystallization are joined together by the branch ed network of hydrogen bonds. The influence of cation nature and compositio n of hydrate shell on the "choice" of geometrical isomer (trans or cis) is discussed for the 3d complexes [M-II(H4-nL)(2)(H2O)(2)](-2n+2).