TRANSITION-METAL COMPLEXES WITH THE NOVEL POLY(1,2,4-TRIAZOLYL)BORATELIGANDS [HNB(C2H2N3)(4-N)](- (N=1 AND 2) - SYNTHESIS AND CHARACTERIZATION OF METAL-COMPLEXES OF DIHYDROBIS(1,2,4-TRIAZOLYL)BORATE AS ONE-DIMENSIONAL OR 2-DIMENSIONAL COORDINATION POLYMERS WITH 6-MEMBERED RING WATER SUBSTRUCTURES AND THE STRUCTURE OF 2-DIMENSIONAL LIQUID AND SOLID WATER AS ORGANIZED IN THE INTERCALATE [NI(HB(C2H2N3)(3))(2)]CENTER-DOT-6H2O (X-RAY

The 1:2 manganese (5), nickel (6), and copper complex (7) with the nov el dihydrobis(1,2,4-triazolyl)borate ligand (2) were synthesized and s tructurally characterized. Single-crystal X-ray studies reveal the for mation of highly solvated coordination polymers of the formula ([M(H2O )(2)(mu-H2B(C2H2N3)(2)}(2)] . n H2O)infinity for M = Mn and Cu. In 5 ( M = Mn; n = 4) a two-dimensional metal-ligand framework is built by me ans of the bridging action of 2. These metal-ligand grid sheets sandwi ch water layers which comprise individual six-membered rings. Compound 7 (M = Cu; n = 6) can be described as a linear metal-ligand chain wit h two borate ligands bridging two copper centers. These one-dimensiona l coordination polymers are separated by one-dimensional arrays of wat er molecules in the form of edge-sharing six-membered rings, In both s tructures the water of crystallization is held in place both by hydrog en bonding from the aqua ligands and by hydrogen bonding to the nitrog en atoms of the berate ligand. Bis[hydrotris(1,2,4-triazolyl)borato]ni ckel, [Ni{HB(C2H2N3)3)(2)] (8), was obtained from NiCl2 and the potass ium salt of [HB(C2H2N3)(3)](-) (1). Single-crystal X-ray structures of the solvate 8 . 6 H2O were determined at 293 and 160 K. The water mol ecules are arranged in two-dimensional layers with only weak (hydrogen bonding) interactions to the adjacent layers of the complex molecules . The room temperature structure (orthorhombic, space group Cmca) show s a highly disordered water structure being indicative of a dynamic eq uilibrium between small conglomerates and free molecules. Upon cooling an ordering occurs in the water layer leading to a phase transition i n the crystal, and in the low-temperature structure at 160 K (orthorho mbic, space group Pmnb) the hydrogen atoms and bonding network of the water structure could be determined. This structure is best described as being composed of individual rings or chain segments. The material surface morphology after loss of the water of crystallization was stud ied by scanning electron microscopy and the structural pattern correla ted with the crystal packing.