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Halis Olmez

Publications and source records attributed to Halis Olmez.

6 recordsLinked to original sources
PubMed2004

mer-Diaquabis(1H-imidazole-kappaN3)(orotato-kappa2N3,O4nickel(II).

The title mononuclear complex, [Ni(C(5)H(2)N(2)O(4))(C(3)H(4)N(2))(2)(H(2)O)(2)] or [Ni(HOr)(im)(2)(H(2)O)(2)] (im is imidazole and H(3)Or is orotic acid, or 2,6-dioxo-1,2,3,6-tetrahydropyrimidine-4-carboxylic acid), has been synthesized and the crystal structure determination is reported. The Ni(II) ion in the complex has a distorted octahedral coordination geometry comprised of one deprotonated pyrimidine N atom and the adjacent carboxylate O atom of the orotate ligand, two tertiary imidazole N atoms and two aqua ligands. An extensive three-dimensional network of OW-H...O and N-H...O hydrogen bonds, and pi-pi and pi-ring interactions are responsible for crystal stabilization.

Journal Article↗
PubMed2004

Diaquabis(pyridine-2-carboxamide-kappa2N1,O2)nickel(II) disaccharinate tetrahydrate.

In the crystal structure of the title compound, [Ni(C6H6N2O)2(H2O)2](C7H4NO3S)2.4H2O or [Ni(pia)2(H2O)2](sac)2.4H2O (pia is picolinamide or pyridine-2-carboxamide, and sac is the saccharinate anion), the Ni2+ cation, located on a centre of symmetry, is coordinated by two symmetry-related aqua ligands together with a pair of symmetry-related bidentate pia molecules and exhibits a distorted octahedral environment. The unique unligated sac anion in the asymmetric unit resides on a general position and has a single negative charge. The coordinated water molecules link the sac ions to the metal complex via O-H...O hydrogen bonds. In addition, the sac ions are linked to the metal complex via intermolecular pi-pi interactions between the benzene ring of the sac ion and the pyridine ring of a pia ligand. Each uncoordinated water molecule is hydrogen bonded to sac moieties through O-H...O and O-H...N hydrogen bonds.

Crystallography, X-Ray↗
PubMed2003

Dinicotinamidium squarate.

The crystal structure determination of the dinicotinamidium squarate salt, 2C(6)H(7)N(2)O(+).C(4)O(4)(2-), is reported, with the squarate dianion residing on an inversion centre and the unique cation in a general position. Salt formation occurs by donation of two H atoms from squaric acid to the nicotinamide base. The crystal packing is derived from three types of hydrogen bonding. The primary hydrogen bond involves a squarate anion O atom and an H atom of the protonated pyridine group of the nicotinamide, with an N.O distance of 2.5760 (13) A. The second hydrogen bond involves a second anion O atom and an amide H atom, with an N.O distance of 2.8374 (14) A. Thirdly, an intermolecular interaction between two coplanar nicotinamide moieties occurs between an amide O atom and a symmetry-related amide H atom, with an N1.O3 distance of 2.8911 (15) A. These hydrogen bonds are also responsible for the planarity of the nicotinamide moiety in the salt.

Journal Article↗