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(1,3-Dimethylimidazolidine-2-selone-,Se)bis(1,10-phenanthroline-,2N,N,)copper(II) bis(perchlorate) and bis(2,2,-bipyridyl-,2N,N,)(imidazolidine-2-thione-,S)copper(II) bis(perchlorate)

ACTA CRYSTALLOGRAPHICA SECTION C, Issue 8 2007
Alexander J. Blake
In the first title salt, [Cu(C12H8N2)2(C5H10N2Se)](ClO4)2, the CuII centre occupies a distorted trigonal,bipyramidal environment defined by four N donors from two 1,10-phenanthroline (phen) ligands and by the Se donor of a 1,3-dimethylimidazolidine-2-selone ligand, with the equatorial plane defined by the Se and by two N donors from different phen ligands and the axial sites occupied by the two remaining N donors, one from each phen ligand. The Cu,N distances span the range 1.980,(10),2.114,(11),Å and the Cu,Se distance is 2.491,(3),Å. Intermolecular ,,, contacts between imidazolidine rings and the central rings of phen ligands generate chains of cations. In the second salt, [Cu(C10H8N2)2(C3H6N2S)](ClO4)2, the CuII centre occupies a similar distorted trigonal,bipyramidal environment comprising four N donors from two 2,2,-bipyridyl (bipy) ligands and an S donor from an imidazolidine-2-thione ligand. The equatorial plane is defined by the S donor and two N donors from different bipy ligands. The Cu,N distances span the range 1.984,(6),2.069,(7),Å and the Cu,S distance is 2.366,(3),Å. Intermolecular ,,, contacts between imidazolidine and pyridyl rings form chains of cations. A major difference between the two structures is due to the presence in the second complex of two N,H...O hydrogen bonds linking the imidazolidine N,H hydrogen-bond donors to perchlorate O-atom acceptors. [source]

4-(2-Hydroxyphenyl)-2-phenyl-2,3-dihydro-1H -1,5-benzodiazepine and the 2-(2,3-dimethoxyphenyl)-, 2-(3,4-dimethoxyphenyl)- and 2-(2,5-dimethoxyphenyl)-substituted derivatives

ACTA CRYSTALLOGRAPHICA SECTION C, Issue 7 2007
Carlos A. Escobar
The 1,5-benzodiazepine ring system exhibits a puckered boat-like conformation for all four title compounds [4-(2-hydroxyphenyl)-2-phenyl-2,3-dihydro-1H -1,5-benzodiazepine, C21H18N2O, (I), 2-(2,3-dimethoxyphenyl)-4-(2-hydroxyphenyl)-2,3-dihydro-1H -1,5-benzodiazepine, C23H22N2O3, (II), 2-(3,4-dimethoxyphenyl)-4-(2-hydroxyphenyl)-2,3-dihydro-1H -1,5-benzodiazepine, C23H22N2O3, (III), and 2-(2,5-dimethoxyphenyl)-4-(2-hydroxyphenyl)-2,3-dihydro-1H -1,5-benzodiazepine, C23H22N2O3, (IV)]. The stereochemical correlation of the two C6 aromatic groups with respect to the benzodiazepine ring system is pseudo-equatorial,equatorial for compounds (I) (the phenyl group), (II) (the 2,3-dimethoxyphenyl group) and (III) (the 3,4-dimethoxyphenyl group), while for (IV) (the 2,5-dimethoxyphenyl group) the system is pseudo-axial,equatorial. An intramolecular hydrogen bond between the hydroxyl OH group and a benzodiazepine N atom is present for all four compounds and defines a six-membered ring, whose geometry is constant across the series. Although the molecular structures are similar, the supramolecular packing is different; compounds (I) and (IV) form chains, while (II) forms dimeric units and (III) displays a layered structure. The packing seems to depend on at least two factors: (i) the nature of the atoms defining the hydrogen bond and (ii) the number of intermolecular interactions of the types O,H...O, N,H...O, N,H...,(arene) or C,H...,(arene). [source]

Packing of ruthenium sensitizer molecules on mostly exposed faces of nanocrystalline TiO2: crystal structure of (NBu4+)2[Ru(H2tctterpy)(NCS)3]2,·0.5,DMSO

APPLIED ORGANOMETALLIC CHEMISTRY, Issue 11 2002
V. Shklover
Abstract An X-ray crystal study of the new ,black dye' sensitizer tri(thiocyanato)(4,4,,4,-tricarboxy-2,2,:6,,2,-terpyridine)ruthenium(II) is reported. In the crystal, strong hydrogen bonds form chains of ruthenium complex dianions with the O···O distances of 2.48,2.54,Å. From the molecular geometry of the dianions, structural models of their close packing on the (101) and (001) crystal surfaces of TiO2 (anatase) have been built. The maximum possible density of molecular packing noticeably exceeds the experimental value. The hydrogen bonding between the anions in monolayers, located on the TiO2 surface, is discussed. Copyright © 2002 John Wiley & Sons, Ltd. [source]

Redetermination of the iron,zinc phase FeZn13

ACTA CRYSTALLOGRAPHICA SECTION C, Issue 3 2000
Renaud Belin
In iron tridecazinc, the FeZn13 unit cell contains two Zn12 icosahedra which are Fe-centred and two Zn2 dumb-bells coordinated by eight icosahedra. Zn12 icosahedra form chains along the c axis by vertex-sharing, and are further interlinked through octahedra-sharing and vertex-to-vertex bonds. [source]