The interaction of D-penicillamine with aldehydes and ketones: 2-phenyl-5,5-dimethylthiazolidine-4-carboxylic acid

1994 ◽  
Vol 72 (7) ◽  
pp. 1621-1624 ◽  
Author(s):  
R.A. Bell ◽  
J.F. Britten ◽  
H.E. Howard-Lock ◽  
C.J.L. Lock ◽  
M. Schmidt
Keyword(s):  
Hydrogen Bonding ◽  
Carboxylic Acid ◽  
Nmr Spectra ◽  
Room Temperature ◽  
Intermolecular Hydrogen Bonding ◽  
X Ray Diffraction ◽  
X Ray ◽  
Aldehydes And Ketones ◽  
Thiazolidine Ring ◽  
C Nmr

The reaction of D-penicillamine and benzaldehyde yielded 2-phenyl-5,5-dimethylthiazolidine-4-carboxylic acid. The structure was determined by single crystal X-ray diffraction. Crystals were monoclinic, P21, a = 9.785(2), b = 6.941(1), c = 10.399(2) Å, β = 114.06(3)°, Z = 2. Intensities were measured on a Rigaku AFC6R diffractometer with Cu Kα radiation and 1881 reflections were used to determine the structure. R = 0.076, wR = 0.048. The compound exists as an amino acid in the 2S,4S configuration. The conformation of the thiazolidine ring is determined by intermolecular hydrogen bonding. Bond lengths and angles are normal. 1H and 13C NMR spectra showed that epimerization takes place in d4-CH3OH solution, and the ratio of 2S,4S diastereomer to 2R,4S diastereomer at room temperature is 65:35.

scholarly journals Exploring the Structural Chemistry of Pyrophosphoramides: N,N′,N″,N‴-Tetraisopropylpyrophosphoramide

Chemistry ◽  
2021 ◽  
Vol 3 (1) ◽  
pp. 149-163
Author(s):  
Duncan Micallef ◽  
Liana Vella-Zarb ◽  
Ulrich Baisch
Keyword(s):  
Crystal Structure ◽  
Mass Spectrometry ◽  
Nuclear Magnetic Resonance ◽  
Hydrogen Bonding ◽  
Nmr Spectroscopy ◽  
Ir Spectroscopy ◽  
Room Temperature ◽  
Intermolecular Hydrogen Bonding ◽  
X Ray Diffraction ◽  
X Ray

N,N′,N″,N‴-Tetraisopropylpyrophosphoramide 1 is a pyrophosphoramide with documented butyrylcholinesterase inhibition, a property shared with the more widely studied octamethylphosphoramide (Schradan). Unlike Schradan, 1 is a solid at room temperature making it one of a few known pyrophosphoramide solids. The crystal structure of 1 was determined by single-crystal X-ray diffraction and compared with that of other previously described solid pyrophosphoramides. The pyrophosphoramide discussed in this study was synthesised by reacting iso-propyl amine with pyrophosphoryl tetrachloride under anhydrous conditions. A unique supramolecular motif was observed when compared with previously published pyrophosphoramide structures having two different intermolecular hydrogen bonding synthons. Furthermore, the potential of a wider variety of supramolecular structures in which similar pyrophosphoramides can crystallise was recognised. Proton (1H) and Phosphorus 31 (31P) Nuclear Magnetic Resonance (NMR) spectroscopy, infrared (IR) spectroscopy, mass spectrometry (MS) were carried out to complete the analysis of the compound.

Inhibitors of the geotropic response in plants. The crystal structures of 2-[(Naphthalen-2-yl)carbamoyl]benzoic acid (β-Naptalam), 2-(Phenylcarbamoyl)-benzoic acid and 2-(5-Phenyl-1,3,4-oxadiazol-2-yl)benzoic acid

1983 ◽  
Vol 36 (12) ◽  
pp. 2455 ◽  
Author(s):  
G Smith ◽  
CHL Kennard ◽  
GF Katekar
Keyword(s):  
Hydrogen Bonding ◽  
Carboxylic Acid ◽  
Benzoic Acid ◽  
Crystal Structures ◽  
Carboxylic Acids ◽  
Intermolecular Hydrogen Bonding ◽  
X Ray Diffraction ◽  
X Ray ◽  
Carboxylic Acid Groups ◽  
Phthalamic Acid

The crystal structures of three geotropically active phthalamic acid derivatives have been determined by means of X-ray diffraction and the structural systematics for the series compared. The three acids are conformationally similar and, in contrast to the tendency among carboxylic acids to form hydrogen-bonded dimers, they exist as monomers with intermolecular hydrogen bonding between the carboxylic acid groups and the nitrogen or oxygen of the amide side chains.

The Crystal and Molecular Structure of the 1:1 Adduct Hydrate of Pyrazine-2,3-dicarboxylic Acid with 1,1-Diethylurea

2000 ◽  
Vol 53 (12) ◽  
pp. 999 ◽  
Author(s):  
Graham Smith ◽  
Colin H. L. Kennard
Keyword(s):  
Hydrogen Bonding ◽  
Carboxylic Acid ◽  
Dicarboxylic Acid ◽  
Lattice Water Molecule ◽  
Crystal And Molecular Structure ◽  
Acid Group ◽  
X Ray Diffraction ◽  
Carboxylic Acid Group ◽  
X Ray ◽  
Bonding Interaction

The adduct hydrate of 1,1-diethylurea with pyrazine-2,3-dicarboxylic acid, [(C6H4N2O4)(C5H12N2O)].H2O has been prepared and characterized using low-temperature single-crystal X-ray diffraction methods. A primary asymmetric cyclic hydrogen-bonding interaction, similar to those found in other adducts of 1,1-diethylurea with the nitro-substituted aromatic acids, was found between the amide group of the substituted urea and one carboxylic acid group of the acid. Further peripheral hydrogen-bonding associations involving both the f irst and the second carboxylic acid groups, urea and the lattice water molecule result in a ribbon polymer structure.

A heterotrimetallic Ni(II)–Dy(III) bis(salamo)-based complex: synthesis, structure and fluorescent property

2018 ◽  
Vol 73 (5) ◽  
pp. 281-288
Author(s):  
Qing Zhao ◽  
Ying-Qi Pan ◽  
Xiao-Yan Li ◽  
Han Zhang ◽  
Wen-Kui Dong
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonding ◽  
Supramolecular Structure ◽  
Fluorescence Spectra ◽  
Intermolecular Hydrogen Bonding ◽  
X Ray Diffraction ◽  
X Ray ◽  
Distorted Octahedral ◽  
Tricapped Trigonal Prism ◽  
Elemental Analyses

AbstractA discrete heterotrinuclear complex [{Ni2LDy(OAc)3(CH3OH)}2] · 2CH3OH · 3CH2Cl2, with a naphthalenediol-based acyclic bis(salamo) ligand H4L, has been synthesized and structurally characterized using elemental analyses, IR, UV/Vis and fluorescence spectra and single crystal X-ray diffraction. The crystal structure shows two crystallographically independent but chemically identical molecules (molecules I and II). All the Ni(II) atoms are hexa-coordinated with slightly distorted octahedral geometries. The central Dy atoms are nona-coordinated with slightly distorted tricapped trigonal prism geometries. An infinite 3D supramolecular structure is formed via intermolecular hydrogen bonding and C–H…π interactions.

Article

1999 ◽  
Vol 77 (5-6) ◽  
pp. 1057-1065
Author(s):  
John T Edward ◽  
Francis L Chubb ◽  
Denis FR Gilson ◽  
Rosemary C Hynes ◽  
Françoise Sauriol ◽  
...  
Keyword(s):  
Nmr Spectra ◽  
Acidic Solution ◽  
Variable Temperature ◽  
X Ray Diffraction ◽  
Nmr Studies ◽  
Cage Compounds ◽  
Amine Nitrogen ◽  
X Ray ◽  
Bridgehead Nitrogen ◽  
C Nmr

Three new cage peroxides, 1,6-diaza-3,4,8,9-tetraoxabicyclo[4.4.2]dodecane (3a),1,6-diaza-3,4,8,9-tetraoxa-11-methylbicyclo[4.4.2]dodecane (3b), and 1,6-diaza-3,4,8,9-tetraoxatricyclo[4.4.2.411,12]hexadecane (4), have been prepared by reaction of 1,2-diaminoethane, 1,2-diaminopropane, and trans-1,2-diaminocyclohexane, respectively, with formaldehyde and hydrogen peroxide in aqueous acidic solution. Their structures have been established by X-ray diffraction, and show the bridgehead nitrogen atoms to be predominantly sp2 hybridized. The structures accord with 1H and 13C NMR spectra. Variable temperature NMR studies show that the diperoxide 3a begins to undergo rapid inversion (on the NMR time scale) at about 303 K; up to 370 K the diperoxides 3b and 4 show no conformational change.Key words: cage compounds, formaldehyde, peroxides, amine nitrogen, hybridization.

Substituenteneinflüsse auf Synthese und Eigenschaften von Hexakis[phosphanaurio(I)]methanium(2+)bis(tetrafluoroboraten) / Substituent Effects in Synthesis and Properties of Hexakis[phosphineaurio(I)]methanium(2 +) Bis(tetrafluoroborates)

1992 ◽  
Vol 47 (12) ◽  
pp. 1725-1735 ◽  
Author(s):  
Hubert Schmidbaur ◽  
Benno Brachthäuser ◽  
Siegfried Gamper ◽  
Annette Schier ◽  
Oliver Steigelmann
Keyword(s):  
Nmr Spectra ◽  
Room Temperature ◽  
Substituent Effects ◽  
Reaction Times ◽  
Phosphine Ligands ◽  
Electronic Effects ◽  
X Ray ◽  
Magnetic Resonance Parameters ◽  
Interstitial Carbon Atom ◽  
C Nmr

Polyaurated carbon complexes of the type [(L–Au)6C]2+ with functionalized phosphine ligands have been prepared by the reaction of the phosphinegold(I) chlorides R(Ph)2PAuCl (R = p-C6H4-Cl 2a,p-C6H4-Br 2b,p-C6H4-CH3 2c,p-C6H4-OCH3 2d,p-C6H4-COOH 2e, p-C6H4–N(CH3)2 2f), R2(Ph)PAuCl (R = p-C6H4-N(CH3)2 2g) and R3PAuCl (R = p-C6H4-N(CH3)2 2h) with tetrakis(dimethoxyboryl)methane in HMPT at room temperature. Clearly depending on the different inductive and mesomeric effects, the preparation of the clusters with substituents like –CH3 3c, –OCH3 3d and –N(CH3)2 3f needs shorter reaction times and the products show better solubility in organic solvents than those with functional groups like –Cl 3a, –Br 3b and –COOH 3e. The 31P magnetic resonance parameters are correlated with electronic effects of the substituents, but the chemical shift of the interstitial carbon atom in the 13C-NMR spectra is largely independent of the coordinating ligands. For the phosphinegold(I) chlorides 2f–h X-ray structure analyses have been performed.

Interactions de l'ion Ag+ avec la glutarimide

1984 ◽  
Vol 62 (7) ◽  
pp. 1287-1291 ◽  
Author(s):  
Johanne Perron ◽  
André L. Beauchamp
Keyword(s):  
Infrared Spectroscopy ◽  
Infrared Spectrum ◽  
Nmr Spectra ◽  
The Other ◽  
Mirror Plane ◽  
Bond Orders ◽  
X Ray Diffraction ◽  
Complex Species ◽  
X Ray ◽  
C Nmr

The 1:1 complex formed between Ag+ ions and glutarimide was investigated by X-ray diffraction, infrared spectroscopy, and 1H and 13C nmr. The crystals are monoclinic, C2/c, a = 13.497(3) Å, b = 9.503(2) Å, c = 9.600(4) Å, β = 92.30(3)°, Z = 4 molecules per cell. The structure was refined on 1086 nonzero [Formula: see text] reflections to R = 0.027. One half of the Ag atoms are linearly coordinated to the N atoms of two deprotonated glutarimide ligands, whereas the other half are surrounded by an approximate tetrahedron of four carbonyl oxygens belonging to two adjacent [Glu–Ag–Glu]− units. The [Glu–Ag–Glu]− groups are joined by tetrahedrally coordinated Ag atoms into infinite chains along the c axis. Complexation introduces a number of changes in the infrared spectrum of glutarimide. They can be related to the disappearance of the N—H vibrator and the change of bond orders in the —C(O)—N—C(O)— portion of the ligand. The nmr spectra show that coordinated glutarimide retains a mirror plane when the Ag complex is dissolved in DMSO. This suggests that the O-bonded Ag atoms dissociate to a large extent in solution, leaving the linear [Glu–Ag–Glu]− ions as the major glutarimide complex species.

Polymorphism of naphthazarin and its relation to solid-state proton transfer. Neutron and X-ray diffraction studies on naphthazarin C

1985 ◽  
Vol 399 (1817) ◽  
pp. 295-319 ◽  
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonding ◽  
Solid State ◽  
Neutron Diffraction ◽  
Room Temperature ◽  
Model Comparison ◽  
Molecular Model ◽  
Molecular Formula ◽  
X Ray Diffraction ◽  
X Ray

The crystal structure of naphthazarin C has been determined by neutron diffraction at 60 and 300 K (λ ═ 0.895 Å; 1 Å ═ 10 -10 m ═ 10 -1 nm) and X-ray diffraction at 300 K. The space group is Pc at 60 K, but P 2 1 /c at 300 K. There are small but significant differences in cell dimensions at the two temperatures: a ═ 7.664 (7.915), b ═ 7.304 (7.262), c ═ 15.16 (15.284) Å; β ═ 114.60 (114.20)°; Z ═ 4; U ═ 771.6 (801.3) Å 3 (values at 300 K in parentheses). Neutron diffraction shows that the Pc and P 2 1 /c structures are related by an order-disorder transition at 110±1 K. Structure analysis (1771 reflections; R F ═ 0.035; R W ═ 0.036) showed that the hydroxyl hydrogens are largely ordered at 60 K, the appropriate molecular formula being 5, 8-dihydroxy-1, 4-naphthadione. Neutron diffraction measurements at 300 K (1769 reflections; R F ═ 0.052) indicated a disordered molecular model with one-half of an hydrogen atom attached to each oxygen. X -ray diffraction measurements on naphthazarin C at 300 K (two independent sets of intensity measurements, one with CuKα and the other with MoKα) support this disordered model. The molecular dimensions for naphthazarin A and B also fit this model. Comparison of the crystal structure of naphthazarin C with those of the A and B polymorphs shows that only the former has intermolecular O─H • • • O hydrogen bonding. The diffraction results combined with the available solid-state n. m. r. data show that there is at room temperature a rapid intramolecular exchange of hydroxylic protons between each pair of oxygen atoms in all three naphthazarin polymorphs. Many 1, 3-diketones exist in an enol form in the solid. These enol forms have been reported to be disordered for about twenty molecules at room temperature (this total includes one molecule studied at 108 K, and four amino-imino systems) and ordered systems have been reported for about fifteen molecules. Intermolecular hydrogen bonding occurs only in a few of these crystals.

scholarly journals Supramolecular frameworks based on [60]fullerene hexakisadducts

2017 ◽  
Vol 13 ◽  
pp. 1-9 ◽  
Author(s):  
Andreas Kraft ◽  
Johannes Stangl ◽  
Ana-Maria Krause ◽  
Klaus Müller-Buschbaum ◽  
Florian Beuerle
Keyword(s):  
Hydrogen Bonding ◽  
Solid State ◽  
Carboxylic Acid ◽  
Structural Integrity ◽  
Structure Stability ◽  
Side Chains ◽  
X Ray Diffraction ◽  
X Ray

[60]Fullerene hexakisadducts possessing 12 carboxylic acid side chains form crystalline hydrogen-bonding frameworks in the solid state. Depending on the length of the linker between the reactive sites and the malonate units, the distance of the [60]fullerene nodes and thereby the spacing of the frameworks can be controlled and for the most elongated derivative, continuous channels are obtained within the structure. Stability, structural integrity and porosity of the material were investigated by powder X-ray diffraction, thermogravimetry and sorption measurements.

Energetic Materials: The Preparation and Structural Characterization of Three Biguanidinium Dinitramides

1997 ◽  
Vol 53 (3) ◽  
pp. 504-512 ◽  
Author(s):  
A. Martin ◽  
A. A. Pinkerton ◽  
R. D. Gilardi ◽  
J. C. Bottaro
Keyword(s):  
Hydrogen Bonding ◽  
Structural Characterization ◽  
Diffraction Data ◽  
Energetic Materials ◽  
Room Temperature ◽  
Asymmetric Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Bond Lengths

Three biguanidinium salts of the energetic dinitramide anion have been prepared and structurally characterized from room-temperature X-ray diffraction data. Biguanidinium mono-dinitramide, (BIGH)(DN), triclinic, P\overline 1, a = 4.3686 (4), b = 9.404 (2), c = 10.742 (1) Å, \alpha = 83.54 (1), \beta = 80.386 (9), \gamma = 79.93 (1)°, V = 426.8 (1) Å3, Z = 2, D x = 1.62 g cm−3. Biguanidinium bis-dinitramide, (BIGH2)(DN)2, monoclinic, C2/c, a = 11.892 (2), b = 8.131 (1), c = 13.038 (2) Å, \beta = 115.79 (1)°, V = 1135.1 (3) Å3, Z = 4, D x = 1.84 g cm−3. Biguanidinium bis-dinitramide monohydrate, (BIGH2)(DN)2.H2O, orthorhombic, P212121, a = 6.4201 (6), b = 13.408 (1), c = 14.584 (2) Å, V = 1255.4 (4) Å3, Z = 4, D x = 1.76 g cm−3. All three structures are characterized by extensive hydrogen bonding. Both the mono- and diprotontated cations consist of two planar halves twisted with respect to each other. The dinitramide anion has a surprisingly variable and asymmetric structure. The two halves of the anion are twisted with respect to each other; however, the twist varies from 5.1 to 28.9°. In addition, the two ends of the anion have significantly different geometries, e.g. the `equivalent' N—N bond lengths differ by up to 0.045 Å.

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