-
IUCrData Mar 2023The title salt, CHNOS ·Cl [systematic name: 2-(4-hy-droxy-2-methyl-1,1-dioxo-1,2-benzo-thia-zine-3-amido)-5-methyl-1,3-thia-zol-3-ium chloride] is the hydro-chloride...
The title salt, CHNOS ·Cl [systematic name: 2-(4-hy-droxy-2-methyl-1,1-dioxo-1,2-benzo-thia-zine-3-amido)-5-methyl-1,3-thia-zol-3-ium chloride] is the hydro-chloride derivative of meloxicam, a drug used to treat pain and inflammation in rheumatic disorders and osteoarthritis. Although its mol-ecular structure is similar to that previously reported for the hydro-bromide analogue, both salts are not isomorphous. Different crystal structures originate from a conformational modification, arising from a degree of rotational freedom for the thia-zolium ring in the cations. By taking as a reference the conformation of meloxicam, the thia-zolium ring is twisted by 10.96 and -16.70° in the hydro-chloride and hydro-bromide salts, while the 1,2-benzo-thia-zine core is a rigid scaffold. This behaviour could explain why meloxicam is a polymorphous compound.
PubMed: 37180348
DOI: 10.1107/S241431462300202X -
IUCrData Sep 2022The title salt, CHNO ·Cl, exhibits multiple hydrogen-bonding inter-actions involving the nitro-imidazolium cation and the chloride anion. Strong hydrogen bonds between...
The title salt, CHNO ·Cl, exhibits multiple hydrogen-bonding inter-actions involving the nitro-imidazolium cation and the chloride anion. Strong hydrogen bonds between the amine hydrogen atom and the chloride anion link the ionic moieties. Of note, with respect to H⋯Cl inter-actions, the central aromatic hydrogen atom displays a shorter inter-action than the other aromatic hydrogen atom. Finally, inter-actions are observed between the nitro moiety and methyl H atoms. While no π-π stacking is observed, anion-π inter-actions are present. The crystal was refined as a two-component twin.
PubMed: 36337461
DOI: 10.1107/S2414314622008781 -
IUCrData Mar 2024The structure of the title compound, [RuCl(CHN)(CHOS)], has monoclinic (2/) symmetry. The Ru-N distances of the coordination compound are influenced by the chloride or...
The structure of the title compound, [RuCl(CHN)(CHOS)], has monoclinic (2/) symmetry. The Ru-N distances of the coordination compound are influenced by the chloride or di-methyl-sulfoxide-κ ligands. The mol-ecular structure exhibits disorder for two of the terminal methyl groups of a dimethyl sulfoxide ligand.
PubMed: 38586520
DOI: 10.1107/S2414314624001913 -
IUCrData Jan 2023The organic cation in the title mol-ecular salt, CHNCl·Cl, exhibits the effect with a C-H bond of the C atom β to the chloro group donating electrons to the...
The organic cation in the title mol-ecular salt, CHNCl·Cl, exhibits the effect with a C-H bond of the C atom β to the chloro group donating electrons to the anti-bonding orbital of the C-Cl bond to stabilize the conformation [Cl-C-C-C = -68.6 (6)°], as confirmed by DFT geometry optimizations that show a lengthening of the C-Cl bond relative to that of the conformation. Of further inter-est is the higher point group symmetry of the crystal (), compared that of the that of the mol-ecular cation, which arises from a supra-molecular head-to-tail square arrangement of four mol-ecular cations that circulate in a counterclockwise direction when viewed down the tetra-gonal axis.
PubMed: 36794055
DOI: 10.1107/S2414314623000159 -
IUCrData Sep 2020In the title salt, [Ni(CHN)(HO)]Cl, the asymmetric unit is comprised of half of the complex cation and a chloride ion with the Ni atom of the cation situated about a...
In the title salt, [Ni(CHN)(HO)]Cl, the asymmetric unit is comprised of half of the complex cation and a chloride ion with the Ni atom of the cation situated about a twofold rotation axis. The six-coordinate Ni atom of the cation is connected to four N atoms from two methyl-substituted ethyelenedi-amine ligands and two water mol-ecules in a slightly distorted octa-hedral environment. The five-membered chelate ring is in a slight envelope conformation. The crystal packing features O-H⋯Cl and N-H⋯Cl inter-molecular inter-actions with the Cl ion forming weak bifurcated hydrogen bonds with nearby water mol-ecules and N-H inter-actions, leading to a three-dimensional supra-molecular network structure.
PubMed: 36338915
DOI: 10.1107/S2414314620011827 -
Acta Crystallographica. Section E,... Aug 2020A tetra-nuclear Zn complex, [Zn(CHNO)Cl(HO)] or {[Zn(HL)(HO)(Cl)](μCl)[Zn(HL)(HO)(Cl)]}, was synthesized by mixing an equimolar amount of a methanol solution containing...
A tetra-nuclear Zn complex, [Zn(CHNO)Cl(HO)] or {[Zn(HL)(HO)(Cl)](μCl)[Zn(HL)(HO)(Cl)]}, was synthesized by mixing an equimolar amount of a methanol solution containing ZnCl and a methanol solution containing the ligand H [1,5-bis-(pyridin-2-yl-methyl-ene)carbono-hydrazide]. In the tetra-nuclear complex, each of the two ligand mol-ecules forms a dinuclear unit that is connected to another dinuclear unit by two bridging chloride anions. In each dinuclear unit, one Zn cation is penta-coordinated in a NOCl in a distorted square-pyramidal geometry, while the other Zn cation is hexa-coordinated in a NOCl environment with a distorted octa-hedral geometry. The basal plane around the penta-coordinated Zn cation is formed by one chloride anion, one oxygen atom, one imino nitro-gen atom and one pyridine nitro-gen atom with the apical position occupied by a chloride anion. The basal plane of the hexa-coordinated Zn cation is formed by one chloride anion, one hydrazinyl nitro-gen atom, one imino nitro-gen atom and one pyridine nitro-gen atom with the apical positions occupied by a water oxygen atom and a bridged chloro anion from another dinuclear unit, leading to a tetra-nuclear complex. A series of intra-molecular C-H⋯Cl hydrogen bonds is observed in each tetra-nuclear unit. In the crystal, the tetra-nuclear units are connected by inter-molecular C-H⋯Cl, C-H⋯O and N-H⋯O hydrogen bonds, forming a planar two-dimensional structure in the plane.
PubMed: 32844027
DOI: 10.1107/S2056989020009834 -
IUCrData Oct 2022The title salt, CHNO·Cl, contains two cations and two anions in the asymmetric unit. The components are linked by O-H⋯Cl and C-H⋯Cl hydrogen bonds, leading to...
The title salt, CHNO·Cl, contains two cations and two anions in the asymmetric unit. The components are linked by O-H⋯Cl and C-H⋯Cl hydrogen bonds, leading to tetra- (square-planar) or penta-coordinated (square-pyramidal) chloride ions. The title salt is isostructural with its bromide analogue.
PubMed: 36405849
DOI: 10.1107/S2414314622010239 -
IUCrData Jun 2021The title compound, CHNO, likely generated through hydrolysis and esterification of 3'-carb-oxy-3-methyl-(1,4'-bipyridin)-1-ium chloride by ethanol, which contained...
The title compound, CHNO, likely generated through hydrolysis and esterification of 3'-carb-oxy-3-methyl-(1,4'-bipyridin)-1-ium chloride by ethanol, which contained water, has a nearly planar conformation. The crystal structure is sustained by one-dimensional chains along the -axis direction based on bifurcated N-H⋯(O,O) hydrogen bonds between the NH group of the 4-oxo-1,4-di-hydro-pyridine ring and the two carbonyl O atoms.
PubMed: 36337321
DOI: 10.1107/S2414314621005551 -
Environmental Science and Pollution... Feb 2021Chlorine (Cl) in the terrestrial environment is of interest from multiple perspectives, including the use of chloride as a tracer for water flow and contaminant... (Review)
Review
Chlorine (Cl) in the terrestrial environment is of interest from multiple perspectives, including the use of chloride as a tracer for water flow and contaminant transport, organochlorine pollutants, Cl cycling, radioactive waste (radioecology; Cl is of large concern) and plant science (Cl as essential element for living plants). During the past decades, there has been a rapid development towards improved understanding of the terrestrial Cl cycle. There is a ubiquitous and extensive natural chlorination of organic matter in terrestrial ecosystems where naturally formed chlorinated organic compounds (Cl) in soil frequently exceed the abundance of chloride. Chloride dominates import and export from terrestrial ecosystems while soil Cl and biomass Cl can dominate the standing stock Cl. This has important implications for Cl transport, as chloride will enter the Cl pools resulting in prolonged residence times. Clearly, these pools must be considered separately in future monitoring programs addressing Cl cycling. Moreover, there are indications that (1) large amounts of Cl can accumulate in biomass, in some cases representing the main Cl pool; (2) emissions of volatile organic chlorines could be a significant export pathway of Cl and (3) that there is a production of Cl in tissues of, e.g. plants and animals and that Cl can accumulate as, e.g. chlorinated fatty acids in organisms. Yet, data focusing on ecosystem perspectives and combined spatiotemporal variability regarding various Cl pools are still scarce, and the processes and ecological roles of the extensive biological Cl cycling are still poorly understood.
Topics: Chlorides; Chlorine; Ecosystem; Halogenation; Soil
PubMed: 33400105
DOI: 10.1007/s11356-020-12144-6