A cleft type receptor which combines an oxyanion hole with electrostatic interactions

2017 ◽  
Vol 15 (21) ◽  
pp. 4571-4578 ◽  
Author(s):  
Omayra H. Rubio ◽  
Sara del Mazo ◽  
Laura M. Monleón ◽  
Luis Simón ◽  
Álvaro G. Temprano ◽  
...  
Keyword(s):  
Carboxylic Acids ◽  
Electrostatic Interactions ◽  
X Ray Diffraction ◽  
Electrostatic Forces ◽  
Oxyanion Hole ◽  
X Ray ◽  
Type Receptor ◽  
Hole Structure

The association of carboxylic acids with a receptor which combines an oxyanion hole structure with electrostatic forces has been studied by X-ray diffraction, finding different arrangements for the H-bond pattern.

Molecular tapes in the structure of isoguaninium chloride

2017 ◽  
Vol 74 (1) ◽  
pp. 108-112 ◽  
Author(s):  
Urszula Anna Budniak ◽  
Paulina Maria Dominiak
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Charge Density ◽  
Interaction Energy ◽  
Electrostatic Interaction ◽  
Electrostatic Interactions ◽  
The Other ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diffraction Structure

Isoguanine, an analogue of guanine, is of intrinsic interest as a noncanonical nucleobase. The crystal structure of isoguaninium chloride (systematic name: 6-amino-2-oxo-1H,7H-purin-3-ium chloride), C5H6N5O+·Cl−, has been determined by single-crystal X-ray diffraction. Structure analysis was supported by electrostatic interaction energy (E es) calculations based on charge density reconstructed with the UBDB databank. In the structure, two kinds of molecular tapes are observed, one parallel to (010) and the other parallel to (50\overline{4}). The tapes are formed by dimers of isoguaninium cations interacting with chloride anions. E es analysis indicates that cations in one kind of tape are oriented so as to minimize repulsive electrostatic interactions.

Hydrogen Bonds in "Carboxyoximes": the Case of Bomane Derivatives

2000 ◽  
Vol 55 (8) ◽  
pp. 677-684 ◽  
Author(s):  
Maciej Kubicki ◽  
Teresa Borowiak ◽  
Wiesław Z. Antkowiak
Keyword(s):  
Carboxylic Acid ◽  
Hydrogen Bonds ◽  
Crystal Structures ◽  
Carboxylic Acids ◽  
Supramolecular Structures ◽  
X Ray Diffraction ◽  
X Ray ◽  
Carboxylic Groups ◽  
Acid Function

Abstract The tendency of forming mixed carboxyl-to-oxime hydrogen bonds was tested on the series of bornane derivatives: one with the acid function only (bornane-2-endo-carboxylic acid), one with the oxime function (2,2′-diethylthiobomane-3-oxime), and one with both oxime and carboxylic functions (bornane-2-oxime-3-endo-carboxylic acid). The crystal structures of these compounds were determined by means of X-ray diffraction. In bornane-2-endo-carboxylic acid and 2,2′-diethylthiobornane-3-oxime 'homogenic' hydrogen bonds were found, and these hydrogen bonds close eight-and six-membered rings, respectively. By contrast, in bornane-2-oxime-3-endo-carboxylic acid 'heterogenic' hydrogen bonds between carboxylic and oxime bonds were found. This carboxylic-oxime, or 'carboxyoxime' system is almost always present in compounds which have both oxime and carboxylic groups; therefore it can be regarded as an element of supramolecular structures (synthon). The presence of such synthons can break the tendency of carboxylic acids and oximes towards crystallizing in centrosymmetric structures.

scholarly journals Synthesis, characterization and structure of the Bis(methyl-cyclopentadienyl)vanadium(IV) carboxylates

2005 ◽  
Vol 3 (1) ◽  
pp. 157-168 ◽  
Author(s):  
Jaromír Vinklarek ◽  
Jan Honzíĉek ◽  
Ivana Císařová ◽  
Martin Pavliŝta ◽  
Jana Holubová
Keyword(s):  
Aqueous Solution ◽  
Single Crystal ◽  
Diffraction Analysis ◽  
Carboxylic Acids ◽  
X Ray Diffraction ◽  
Monocarboxylic Acids ◽  
X Ray ◽  
Different Types ◽  
Chelate Compounds ◽  
Parameter Values

AbstractThe 1,1’-dimethylvanadocene dichloride ((C5H4CH3)2VCl2) reacts in aqueous solution with various carboxylic acids giving two different types of complexes. The 1,1’-dimethylvanadocene complexes of monocarboxylic acids (C5H4CH3)2V(OOCR)2 (R=H,CCl3, CF3, C6H5) contain two monodentate carboxylic ligands, whereas oxalic and malonic acids act as chelate compounds of the formula (C5H4CH3)2V(OOC-A-COO) (A=−, CH2). The structure of the (C5H4CH3)2 V(OOCCF3)2 complex was determined by single crystal X-ray diffraction analysis. The isotropic and anisotropic EPR spectra of all the complexes prepared were recorded. The obtained EPR parameter values were found to be in agreement with proposed structures.

Polymorphism of Trimeric Perfluoro-ortho-phenylene Mercury, [Hg(o-C6F4)]3

2004 ◽  
Vol 59 (11-12) ◽  
pp. 1483-1487 ◽  
Author(s):  
Mason R. Haneline ◽  
François P. Gabbaï
Keyword(s):  
Single Crystal ◽  
Electrostatic Interactions ◽  
Van Der Waals ◽  
Relativistic Effects ◽  
Van Der Waals Interactions ◽  
X Ray Diffraction ◽  
X Ray ◽  
Π Interactions

Three new modifications of trimeric perfluoro-ortho-phenylene mercury (2) have been investigated by single crystal X-ray diffraction. In each of these modifications, the molecules of 2 form extended stacks. Within each stack, the successive molecules are parallel and separated by approximately 3.3 - 3.4 Å. The packing observed in the different structures is rationalized on the basis of secondary mercury-π interactions, mercuriophilic interactions and electrostatic interactions. Altogether, little preference is given for one particular type of interaction. The packing appears to be dominated by non-directional van der Waals interactions between molecules of 2 which are largely aromatic and whose overall polarizability is magnified by relativistic effects at the mercury(II) centers.

Molecular Cocrystals of Carboxylic Acids. XV. Preparation and Characterization of Heterocyclic Base Adducts With a Series of Carboxylic Acids, and the Crystal Structures of the Adducts of 2-Aminopyrimidine With 2,6-Dihydroxybenzoic Acid, 4-Aminobenzoic Acid, Phenoxyacetic Acid, (2,4-Dichlorophenoxy)acetic Acid, (3,4-Dichlorophenoxy)-acetic Acid and Salicylic Acid, and 2-Aminopyridine With 2,6-Dihydroxybenzoic Acid

1994 ◽  
Vol 47 (6) ◽  
pp. 1097 ◽  
Author(s):  
DE Lynch ◽  
G Smith ◽  
D Freney ◽  
KA Byriel ◽  
CHL Kennard
Keyword(s):  
Acetic Acid ◽  
Salicylic Acid ◽  
Carboxylic Acids ◽  
Phenoxyacetic Acid ◽  
Aminobenzoic Acid ◽  
X Ray Diffraction ◽  
Dihydroxybenzoic Acid ◽  
Heterocyclic Base ◽  
X Ray ◽  
Dichlorophenoxy Acetic Acid

The molecular adducts of the heterocyclic base 2-aminopyrimidine with the aromatic and aromatic aliphatic carboxylic acids salicylic acid, 2,6-dihydroxybenzoic acid and 4-aminobenzoic acid, phenoxyacetic acid, (2,4-dichlorophenoxy)acetic acid, and (3,4-dichlorophenoxy)acetic acid have been prepared, and their interactive modes characterized by single-crystal X-ray diffraction methods. In addition, the complexes with (4-chlorophenoxy)acetic acid, (2,3-dichlorophenoxy)acetic acid, (4-chloro-2-methylphenoxy)acetic acid and (2,4,5- trichlorophenoxy)acetic acid have been characterized by analytical methods, including infrared spectroscopy. Except for the phenoxyacetic acid adduct (2:1), all form 1:1 molecular associations in which the carboxylic acid shows a variable tendency to protonate the hetero nitrogen of the base. The 1:1 complex of 2-aminopyridine with 2,6-dihydroxybenzoic acid has also been characterized by single-crystal X-ray diffraction.

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.

scholarly journals Gold(I) Complexes with Ferrocenylphosphino Sulfonate Ligands: Synthesis and Application in the Catalytic Addition of Carboxylic Acids to Internal Alkynes in Water

Catalysts ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 955 ◽  
Author(s):  
Javier Francos ◽  
María Esther Moreno-Narváez ◽  
Victorio Cadierno ◽  
Diego Sierra ◽  
Katherine Ariz ◽  
...  
Keyword(s):  
Diffraction Study ◽  
Carboxylic Acids ◽  
Reaction Medium ◽  
Synthesis And Characterization ◽  
X Ray Diffraction ◽  
X Ray ◽  
Internal Alkynes ◽  
Unsaturated Carboxylic Acids ◽  
Catalytic Addition

The synthesis and characterization of novel gold(I) complexes containing hydrophilic ferrocenylphosphino sulfonate ligands, i.e., compounds [AuCl{(η5-C5H3PR2(SO3iPr))Fe(η5-C5H5)}] (R = Ph (2a), p-Tol (2b), Cy (2c)), are presented, including a single-crystal X-ray diffraction study on 2a. Complexes 2a–c were checked as catalysts for the intermolecular addition of carboxylic acids to nonactivated internal alkynes using water as a green reaction medium. The best results in terms of activity were obtained with 2a in combination with AgOAc, which was able to promote the selective anti addition of a variety of aromatic, aliphatic, and α,β-unsaturated carboxylic acids to both symmetrical and unsymmetrical internal alkynes at 60 °C, employing metal loadings of only 2 mol %.

scholarly journals Structure of [60]fullerene with a mobile lithium cation inside

2018 ◽  
Vol 5 (7) ◽  
pp. 180337 ◽  
Author(s):  
Shinobu Aoyagi ◽  
Kazuhira Miwa ◽  
Hiroshi Ueno ◽  
Hiroshi Okada ◽  
Yutaka Matsuo ◽  
...  
Keyword(s):  
Thermal Properties ◽  
Synchrotron Radiation ◽  
Electrostatic Interactions ◽  
Lithium Cation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Charge Densities ◽  
Orientation Disorder ◽  
Cubic Structure ◽  
Orientation Ordering

The structure of crystalline [60]fullerene with a lithium cation inside (Li + @C 60 ) was determined by synchrotron radiation X-ray diffraction measurements to understand the electrostatic and thermal properties of the encapsulated Li + cation. Although the C 60 cages show severe orientation disorder in [Li + @C 60 ](TFPB − )·C 4 H 10 O and [Li + @C 60 ](TFSI − )·CH 2 Cl 2 , the Li + cations are rather ordered at specific positions by electrostatic interactions with coordinated anions outside the C 60 cage. The Li + @C 60 molecules in [Li + @C 60 ](ClO 4 − ) with a rock-salt-type cubic structure are fully disordered with almost uniform spherical shell charge densities even at 100 K by octahedral coordination of ClO 4 − tetrahedra and show no orientation ordering, unlike [Li + @C 60 ](PF 6 − ) and pristine C 60 . Single-bonded (Li + @C 60 − ) 2 dimers in [Li + @C 60 − ](NiOEP)⋅CH 2 Cl 2 are thermally stable even at 400 K and form Li + –C bonds which are shorter than Li + –C bonds in [Li + @C 60 ](PF 6 − ) and suppress the rotational motion of the Li + cations.

Synthesis, characterization and electrochemistry of bismuth porphyrins: X-ray crystal structure of (OEP)Bi(SO3CF3)

2000 ◽  
Vol 04 (03) ◽  
pp. 261-270 ◽  
Author(s):  
LYDIE MICHAUDET ◽  
DOMINIQUE FASSEUR ◽  
ROGER GUILARD ◽  
ZHONGPING OU ◽  
KARL M. KADISH ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Electrostatic Interactions ◽  
Free Base ◽  
X Ray Diffraction ◽  
X Ray ◽  
H Nmr ◽  
Vis Spectroscopy ◽  
Bismuth Salts ◽  
Porphyrin Macrocycles

The metalation of several free base porphyrins by the bismuth salts Bi(NO3)3 and Bi(SO3CF3)3 in DMF or pyridine is described. The resulting stable Bi(III) porphyrin complexes are characterized by electrochemistry, 1H NMR and UV-vis spectroscopy. The structure of ( OEP ) Bi ( SO 3 CF 3) was also determined by single-crystal X-ray diffraction and shows that ( OEP ) Bi ( SO 3 CF 3) exists as a dimer which is stabilized by electrostatic interactions in which the two [(OEP)Bi]+ cations are linked via oxygen atoms of two symmetrically related [Formula: see text] anions, leading to a heptacoordinated bismuth center. Electrochemical oxidation of ( OEP ) Bi ( SO 3 CF 3) and ( T p TP ) Bi ( SO3CF3 ) shows that only the porphyrin macrocycles are oxidized.

scholarly journals Understanding the interactions between the bis(trifluoromethylsulfonyl)imide anion and absorbed CO2 using X-ray diffraction analysis of a soft crystal surrogate

2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Xin Zheng ◽  
Katsuo Fukuhara ◽  
Yuh Hijikata ◽  
Jenny Pirillo ◽  
Hiroyasu Sato ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Diffraction Analysis ◽  
Electrostatic Interactions ◽  
Deep Understanding ◽  
Crystalline Material ◽  
X Ray Diffraction ◽  
Absorption Properties ◽  
X Ray ◽  
Soft Crystal ◽  
Insight Into

Abstract The selective carbon dioxide (CO2) absorption properties of ionic liquids (ILs) are highly pertinent to the development of methods to capture CO2. Although it has been reported that fluorinated components give ILs enhanced CO2 solubilities, it has been challenging to gain a deep understanding of the interactions occurring between ILs and CO2. In this investigation, we have utilized the soft crystalline material [Cu(NTf2)2(bpp)2] (NTf2‒ = bis(trifluoromethylsulfonyl)imide, bpp = 1,3-bis-(4-pyridyl)propane) as a surrogate for single-crystal X-ray diffraction analysis to visualize interactions occurring between CO2 and NTf2‒, the fluorinated IL component that is responsible for high CO2 solubility. Analysis of the structure of a CO2-loaded crystal reveals that CO2 interacts with both fluorine and oxygen atoms of NTf2‒ anions in a trans rather than cis conformation about the S–N bond. Theoretical analysis of the structure of the CO2-loaded crystal indicates that dispersion and electrostatic interactions exist between CO2 and the framework. The overall results provide important insight into understanding and improving the CO2 absorption properties of ILs.

Sign in / Sign up

Export Citation Format

Share Document