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Tartrate Anion (tartrate + anion)
Selected AbstractsVibrational spectral studies and the non-linear optical properties of a novel NLO material L -prolinium tartrateJOURNAL OF RAMAN SPECTROSCOPY, Issue 12 2006L. Padmaja Abstract Vibrational spectral analysis of the novel non-linear optical (NLO) material, L -prolinium tartrate (LPT) was carried out using NIR-FT-Raman and FT-IR spectroscopy. The density functional theoretical (DFT) computations have been performed at B3LYP/6,31G (d) level to derive equilibrium geometry, vibrational wavenumbers, intensities and first hyperpolarizability. The reasonable NLO efficiency, predicted for the first time in this novel compound, has been confirmed by Kurtz,Perry powder second-harmonic generation (SHG) experiments. The charge-transfer interaction between the pyrrolidine ring and the carbonyl group of the tartrate anion through the intramolecular ionic hydrogen bonds is confirmed by the simultaneous activation of ring modes in IR and Raman spectra. The splitting of the ring-breathing mode, pseudo-rotational ring puckering modes and the NH2 modes of the pyrrolidine ring lead to the conclusion that the pyrrolidine ring adopts a conformation intermediate between the envelope (bent) form and the half-chair (twisted) form, resulting in the lowering of symmetry from C2 to Cs. The lowering of the methylenic stretching wavenumbers and the enhancement of the stretching intensities suggest the existence of the electronic effects of back-donation in LPT. The positional disorder of the pyrrolidine ring, the presence of blue-shifting H-bonds as well as other non-bonded interactions in LPT, low frequency H-bond vibrations and the role of intramolecular charge transfer and the hydrogen bonds in making the molecule NLO active have been analysed on the basis of the vibrational spectral features. Copyright © 2006 John Wiley & Sons, Ltd. [source] Phenyl-ring rotational disorder in the two-dimensional hydrogen-bonded structure of the 1:1 proton-transfer salt of the diazo-dye precursor 4-(phenyldiazenyl)aniline (aniline yellow) with l -tartaric acidACTA CRYSTALLOGRAPHICA SECTION C, Issue 7 2010Graham Smith In the structure of the 1:1 proton-transfer compound from the reaction of l -tartaric acid with the azo-dye precursor aniline yellow [4-(phenyldiazenyl)aniline], namely 4-(phenyldiazenyl)anilinium (2R,3R)-3-carboxy-2,3-dihydroxypropanoate, C12H12N3+·C4H5O6,, the asymmetric unit contains two independent 4-(phenyldiazenyl)anilinium cations and two hydrogen l -tartrate anions. The structure is unusual in that all four phenyl rings of the two cations have identical rotational disorder with equal occupancy of the conformations. The two hydrogen l -tartrate anions form independent but similar chains through head-to-tail carboxyl,carboxylate O,H...O hydrogen bonds [graph set C(7)], which are then extended into a two-dimensional hydrogen-bonded sheet structure through hydroxy O,H...O hydrogen-bonded links. The anilinium groups of the 4-(phenyldiazenyl)anilinium cations are incorporated into the sheets and also provide internal hydrogen-bonded extensions, while their aromatic tails are layered in the structure without significant association except for weak ,,, interactions [minimum ring centroid separation = 3.844,(3),Å]. The hydrogen l -tartrate residues of both anions exhibit the common short intramolecular hydroxy,carboxylate O,H...O hydogen bonds. This work provides a solution to the unusual disorder problem inherent in the structure of this salt, as well as giving another example of the utility of the hydrogen tartrate anion in the generation of sheet substructures in molecular assembly processes. [source] Hydrogen-bonded supramolecular motifs in 2-amino-4,6-dimethoxypyrimidinium 4-hydroxybenzoate monohydrate, 2-amino-4,6-dimethoxypyrimidinium 6-carboxypyridine-2-carboxylate monohydrate and 2-amino-4,6-dimethoxypyrimidinium hydrogen (2R,3R)-tartrate 2-amino-4,6-dimethoxypyrimidineACTA CRYSTALLOGRAPHICA SECTION C, Issue 5 2007Kaliyaperumal Thanigaimani In the crystal structures of the title compounds, C6H10N3O2+·C7H5O3,·H2O, (I), C6H10N3O2+·C7H4NO4,·H2O, (II), and C6H10N3O2+·C4H5O6,·C6H9N3O2, (III), the 2-amino-4,6-dimethoxypyrimidinium cation [abbreviated as (MeO)2 -Hampy+] interacts with the carboxylate group of the corresponding anion through a pair of nearly parallel N,H...O hydrogen bonds to form R22(8) ring motifs. In (I), the (MeO)2 -Hampy+ cation is centrosymmetrically paired through a pair of N,H...N hydrogen bonds involving the 2-amino group and a ring N atom forming an R22(8) motif. In (II), inversion-related R22(8) motifs (amino,pyrimidine,carboxylate motifs) are further bridged by N,H...O hydrogen bonds on either side forming a DDAA array of quadruple hydrogen bonds. This array is extended further on either side by Owater,H...Omethoxy hydrogen bonds, resulting in an array of six hydrogen bonds (ADDAAD). The water molecule plays a pivotal role, and five hydrogen-bonded fused rings are formed around the water molecule. In (III), the carboxy group of the tartrate anion interacts with the ring N atom and 2-amino group of the neutral (MeO)2 -ampy molecule through N,H...O and O,H...N hydrogen bonds. There is also an intramolecular O,H...O hydrogen bond in the tartrate anion. In all three crystal structures, C,H...O hydrogen bonds are observed. [source] Synthesis and Enantioselective Discrimination of Chiral Fluorescence Receptors Bearing Amino Acid UnitsCHINESE JOURNAL OF CHEMISTRY, Issue 3 2007Kuo-Xi Xu Abstract Two chiral fluorescence receptors (1, 2) were synthesized, and their structures were characterized by IR, 1H NMR, 13C NMR, mass spectra and elemental analysis. The chiral recognition of receptors was studied by 1H NMR and fluorescence spectra. The results demonstrate that receptors and dibenzoyl tartrate anion formed a 1:1 complex. The receptor 1 exhibited a good enantioselective recognition ability toward the enantiomers of dibenzoyl tartrate anion. [source] Racemic calcium tartrate tetrahydrate [form (II)] in rat urinary stonesACTA CRYSTALLOGRAPHICA SECTION B, Issue 3 2009A. Le Bail The title compound, [Ca(C4H4O6)]·4H2O, calcium tartrate tetrahydrate, is a new triclinic centrosymmetric form identified in rat kidney calculus. The crystal structure was determined from powder and single-crystal X-ray diffraction. The four water molecules belong to one square face of the Ca-atom coordination (a square antiprism), the four O atoms of the second square face coming from two tartrate anions, building infinite chains alternating Ca atom polyhedra and tartrate anions along a, with the chains cross-linked by a network of hydrogen bonds. [source] Phenyl-ring rotational disorder in the two-dimensional hydrogen-bonded structure of the 1:1 proton-transfer salt of the diazo-dye precursor 4-(phenyldiazenyl)aniline (aniline yellow) with l -tartaric acidACTA CRYSTALLOGRAPHICA SECTION C, Issue 7 2010Graham Smith In the structure of the 1:1 proton-transfer compound from the reaction of l -tartaric acid with the azo-dye precursor aniline yellow [4-(phenyldiazenyl)aniline], namely 4-(phenyldiazenyl)anilinium (2R,3R)-3-carboxy-2,3-dihydroxypropanoate, C12H12N3+·C4H5O6,, the asymmetric unit contains two independent 4-(phenyldiazenyl)anilinium cations and two hydrogen l -tartrate anions. The structure is unusual in that all four phenyl rings of the two cations have identical rotational disorder with equal occupancy of the conformations. The two hydrogen l -tartrate anions form independent but similar chains through head-to-tail carboxyl,carboxylate O,H...O hydrogen bonds [graph set C(7)], which are then extended into a two-dimensional hydrogen-bonded sheet structure through hydroxy O,H...O hydrogen-bonded links. The anilinium groups of the 4-(phenyldiazenyl)anilinium cations are incorporated into the sheets and also provide internal hydrogen-bonded extensions, while their aromatic tails are layered in the structure without significant association except for weak ,,, interactions [minimum ring centroid separation = 3.844,(3),Å]. The hydrogen l -tartrate residues of both anions exhibit the common short intramolecular hydroxy,carboxylate O,H...O hydogen bonds. This work provides a solution to the unusual disorder problem inherent in the structure of this salt, as well as giving another example of the utility of the hydrogen tartrate anion in the generation of sheet substructures in molecular assembly processes. [source] Three-dimensional hydrogen-bonded structures in the 1:1 proton-transfer compounds of l -tartaric acid with the associative-group monosubstituted pyridines 3-aminopyridine, 3-carboxypyridine (nicotinic acid) and 2-carboxypyridine (picolinic acid)ACTA CRYSTALLOGRAPHICA SECTION C, Issue 1 2010Graham Smith The 1:1 proton-transfer compounds of l -tartaric acid with 3-aminopyridine [3-aminopyridinium hydrogen (2R,3R) -tartrate dihydrate, C5H7N2+·C4H5O6,·2H2O, (I)], pyridine-3-carboxylic acid (nicotinic acid) [anhydrous 3-carboxypyridinium hydrogen (2R,3R)-tartrate, C6H6NO2+·C4H5O6,, (II)] and pyridine-2-carboxylic acid [2-carboxypyridinium hydrogen (2R,3R)-tartrate monohydrate, C6H6NO2+·C4H5O6,·H2O, (III)] have been determined. In (I) and (II), there is a direct pyridinium,carboxyl N+,H...O hydrogen-bonding interaction, four-centred in (II), giving conjoint cyclic R12(5) associations. In contrast, the N,H...O association in (III) is with a water O-atom acceptor, which provides links to separate tartrate anions through Ohydroxy acceptors. All three compounds have the head-to-tail C(7) hydrogen-bonded chain substructures commonly associated with 1:1 proton-transfer hydrogen tartrate salts. These chains are extended into two-dimensional sheets which, in hydrates (I) and (III) additionally involve the solvent water molecules. Three-dimensional hydrogen-bonded structures are generated via crosslinking through the associative functional groups of the substituted pyridinium cations. In the sheet struture of (I), both water molecules act as donors and acceptors in interactions with separate carboxyl and hydroxy O-atom acceptors of the primary tartrate chains, closing conjoint cyclic R44(8), R34(11) and R33(12) associations. Also, in (II) and (III) there are strong cation carboxyl,carboxyl O,H...O hydrogen bonds [O...O = 2.5387,(17),Å in (II) and 2.441,(3),Å in (III)], which in (II) form part of a cyclic R22(6) inter-sheet association. This series of heteroaromatic Lewis base,hydrogen l -tartrate salts provides further examples of molecular assembly facilitated by the presence of the classical two-dimensional hydrogen-bonded hydrogen tartrate or hydrogen tartrate,water sheet substructures which are expanded into three-dimensional frameworks via peripheral cation bifunctional substituent-group crosslinking interactions. [source] Two salts of di- p -toluoyltartaric acid with aromatic aminesACTA CRYSTALLOGRAPHICA SECTION C, Issue 6 2006Luigi R Nassimbeni The structures of bis[(R)-(+)-1-phenylethylammonium] (2R,3R)-(,)-2,3-di- p -toluoyloxybutanedioate methanol disolvate monohydrate, 2C8H12N+·C20H16O82,·2CH4O·H2O, (I), and bis(benzylammonium) (2R,3R)-(,)-2,3-di- p -toluoyloxybutanedioate dihydrate, 2C7H10N+·C20H16O82,·2H2O, (II), exhibit extensive hydrogen bonding, with (N,)H,O and (O,)H,O distances in the ranges 2.716,(2),2.929,(3) and 2.687,(2),2.767,(2),Å, respectively, in (I), and 2.673,(2),2.888,(2) and 2.785,(2),2.931,(2),Å, respectively, in (II). The amine groups are protonated and the carboxylate groups of the tartrate anions are fully deprotonated. The conformation of the toluoyltartrate anion and its molecular parameters are similar in both structures. [source] | ||||||||||