Diethyl 2-Benzimidazol-1-ylsuccinate–Picric Acid (1/1) – An Inclusion Molecular Complex

1997 ◽  
Vol 53 (6) ◽  
pp. 961-967 ◽  
Author(s):  
P. Zaderenko ◽  
M. S. Gil ◽  
P. López ◽  
P. Ballesteros ◽  
I. Fonseca ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Molecular Complex ◽  
Picric Acid ◽  
X Ray Diffraction ◽  
Nmr Studies ◽  
X Ray ◽  
H Nmr ◽  
Intramolecular Hydrogen ◽  
C Nmr

The crystal structure of the diethyl 2-benzimidazol-1-ylsuccinate–picric acid (1/1) molecular complex has been determined by X-ray diffraction analysis. Diethyl 2-benzimidazol-l-ylsuccinate molecules form channels along the a axis, in which the picric acid molecules are located. The benzimidazole moiety and the phenol group are held together by hydrogen bonding between the hydrogen of the phenol and the N3 atom of benzimidazole. Additionally, this hydrogen forms an intramolecular hydrogen bond with one O atom of the ortho-nitro group, thus producing a bifurcated hydrogen bond. 1H NMR spectra in DMSO-d 6 solution and CP/MAS solid 13 C NMR studies of this 2-benzimidazol-1-ylsuccinate–picric acid (1/1) molecular complex, as well as those of dimethyl, diethyl, di-n-butyl and 1-n-butyl-4-ethyl 2-imidazol-1-ylsuccinates, diethyl 2-pyrazol-1-ylsuccinate, ethyl imidazol-1-ylacetate, ethyl pyrazol-1-ylacetate and ethyl pyrazol-l-ylsuccinate, suggest that the picric acid linkage depends on the nature of the azole. Actual proton transfer is deduced for the imidazole derivatives, but only weak hydrogen bonding could be inferred for pyrazole derivatives.

Intramolecular hydrogen bonding in N-salicylideneanilines. X-ray diffraction and solid-state NMR studies

1995 ◽  
Vol 91 (1) ◽  
pp. 77 ◽  
Author(s):  
Krzysztof Wozniak ◽  
Heyong He ◽  
Jacek Klinowski ◽  
William Jones ◽  
Teresa Dziembowska ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Solid State ◽  
Solid State Nmr ◽  
Intramolecular Hydrogen Bonding ◽  
X Ray Diffraction ◽  
Nmr Studies ◽  
X Ray ◽  
Intramolecular Hydrogen

scholarly journals Synthesis and Complexation Properties of 2-Hydroxy-5-methoxyphenylphosphonic Acid (H3L1). Crystal Structure of the [Cu(H2L1)2(Н2О)2] Complex

2021 ◽  
Vol 91 (11) ◽  
pp. 2176-2186
Author(s):  
G. S. Tsebrikova ◽  
Yu. I. Rogacheva ◽  
I. S. Ivanova ◽  
A. B. Ilyukhin ◽  
V. P. Soloviev ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Methoxy Group ◽  
Protonation Constants ◽  
Water Molecules ◽  
X Ray Diffraction ◽  
X Ray ◽  
The Stability ◽  
Intramolecular Hydrogen ◽  
Oxygen Atoms

Abstract 2-Hydroxy-5-methoxyphenylphosphonic acid (H3L1) and the complex [Cu(H2L1)2(H2O)2] were synthesized and characterized by IR spectroscopy, thermogravimetry, and X-ray diffraction analysis. The polyhedron of the copper atom is an axially elongated square bipyramid with oxygen atoms of phenolic and of monodeprotonated phosphonic groups at the base and oxygen atoms of water molecules at the vertices. The protonation constants of the H3L1 acid and the stability constants of its Cu2+ complexes in water were determined by potentiometric titration. The protonation constants of the acid in water are significantly influenced by the intramolecular hydrogen bond and the methoxy group. The H3L1 acid forms complexes CuL‒ and CuL24‒ with Cu2+ in water.

Adsorption behaviour of a CdII–triazole MOF for butan-2-one in a single-crystal-to-single-crystal (SCSC) fashion: the role of hydrogen bonding and C—H...π interactions

2019 ◽  
Vol 75 (6) ◽  
pp. 806-811
Author(s):  
Jia Wang ◽  
Tianchao You ◽  
Teng Wang ◽  
Qikui Liu ◽  
Jianping Ma ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Single Crystal ◽  
Specific Binding ◽  
Supramolecular Interactions ◽  
Adsorption Behaviour ◽  
X Ray Diffraction ◽  
Guest Molecules ◽  
X Ray ◽  
Π Interactions ◽  
H Nmr

The adsorption behaviour of the CdII–MOF {[Cd(L)2(ClO4)2]·H2O (1), where L is 4-amino-3,5-bis[3-(pyridin-4-yl)phenyl]-1,2,4-triazole, for butan-2-one was investigated in a single-crystal-to-single-crystal (SCSC) fashion. A new host–guest system that encapsulated butan-2-one molecules, namely poly[[bis{μ3-4-amino-3,5-bis[3-(pyridin-4-yl)phenyl]-1,2,4-triazole}cadmium(II)] bis(perchlorate) butanone sesquisolvate], {[Cd(C24H18N6)2](ClO4)2·1.5C4H8O} n , denoted C4H8O@Cd-MOF (2), was obtained via an SCSC transformation. MOF 2 crystallizes in the tetragonal space group P43212. The specific binding sites for butan-2-one in the host were determined by single-crystal X-ray diffraction studies. N—H...O and C—H...O hydrogen-bonding interactions and C—H...π interactions between the framework, ClO4 − anions and guest molecules co-operatively bind 1.5 butan-2-one molecules within the channels. The adsorption behaviour was further evidenced by 1H NMR, IR, TGA and powder X-ray diffraction experiments, which are consistent with the single-crystal X-ray analysis. A 1H NMR experiment demonstrates that the supramolecular interactions between the framework, ClO4 − anions and guest molecules in MOF 2 lead to a high butan-2-one uptake in the channel.

scholarly journals A series of Mn(i) photo-activated carbon monoxide-releasing molecules with benzimidazole coligands: synthesis, structural characterization, CO releasing properties and biological activity evaluation

RSC Advances ◽  
2019 ◽  
Vol 9 (36) ◽  
pp. 20505-20512 ◽  
Author(s):  
Mixia Hu ◽  
YaLi Yan ◽  
Baohua Zhu ◽  
Fei Chang ◽  
Shiyong Yu ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Biological Activity ◽  
Activated Carbon ◽  
Fluorescence Spectroscopy ◽  
Single Crystal ◽  
Structural Characterization ◽  
X Ray Diffraction ◽  
X Ray ◽  
H Nmr ◽  
C Nmr

Five Mn(i) photo-activated carbon monoxide-releasing molecules were synthesized by reactions of MnBr(CO)5 with L1–L4, and characterized via single crystal X-ray diffraction, 1H-NMR, 13C-NMR, IR, UV-vis and fluorescence spectroscopy.

Microbial Transformation of Glycyrrhetinic Acid by Colletotrichum lini AS3.4486

2015 ◽  
Vol 1120-1121 ◽  
pp. 877-881
Author(s):  
Chao Jun He ◽  
Yu Min Yang ◽  
Kong Yang Wu
Keyword(s):  
Single Crystal ◽  
Microbial Transformation ◽  
Glycyrrhetinic Acid ◽  
Conversion Product ◽  
X Ray Diffraction ◽  
Orthorhombic Space Group ◽  
X Ray ◽  
H Nmr ◽  
Sole Product ◽  
C Nmr

The biotransformation of 18β-glycyrrhetinic acid by Colletotrichum lini AS3.4486 was investigated. The conversion reaction was carried out for 72h, and the sole product was isolated by column chromatography and elucidated as 7β,15α-dihydroxy-18β-glycyrrhetinic acid by HR-ESI-MS, 1H-NMR , 13C-NMR and single–crystal X-ray diffraction. The crystal of the conversion product belongs to orthorhombic, space group P212121 with 11.828(1), 13.213(2), 19.606(2) Å , V = 3064.0 Å3, Z = 4. This study povides a new method for the synthesis of 7β,15α-dihydroxy-18β-glycyrrhetinic acid.

β-Hydroxydithiozimtsäurederivate als Liganden. Synthese und Charakterisierung neuartiger 1,1-Ethendithiolato- und O,S-Chelatkomplexe / Derivatives of β -Hydroxydithiocinnamic Acids as Ligands. Syntheses and Characterisation of Novel 1,1-Ethenedithiolato and O,S-Chelate Complexes

2007 ◽  
Vol 62 (3) ◽  
pp. 475-482 ◽  
Author(s):  
Karsten Schubert ◽  
Helmar Görls ◽  
Wolfgang Weigand
Keyword(s):  
Bidentate Ligand ◽  
Molecular Structures ◽  
X Ray Diffraction ◽  
Chelate Complexes ◽  
X Ray ◽  
H Nmr ◽  
Hexyl Ester ◽  
Elemental Analyses ◽  
Derivatives Of ◽  
C Nmr

Starting from 4-bromoacetophenone 1, the 4-bromo-β -hydroxydithiocinnamic acid 2 and the 4-bromo-β -hydroxydithiocinnamic acid hexyl ester 3 were prepared using carbon disulfide and potassium-tert-butylate as a base. Acting as a ligand, the acid gives 1,1-ethenedithiolato complexes with (Ph3P)2Pt(II) (4a), (Et3P)2Pt(II) (4b), dppePt(II) (4c), (Ph3P)2Pd(II) (4d), dppePd(II) (4e), and dppeNi(II) (4f). In contrast to the acid, the deprotonated ester 3 forms a monoanionic bidentate ligand. [O,S] Complexes of Pt(II) (5a), Pd(II) (5b) and Ni(II) (5c) were obtained. All complexes have been fully characterised using 1H NMR, 13C NMR and 31P NMR spectroscopy, mass spectrometry, infrared spectroscopy and elemental analyses. The molecular structures of the complexes 4b and 5a - 5c were determined by X-ray diffraction analyses.

Tautomerism in 3{5}-(dimethoxyphenyl)pyrazoles

1996 ◽  
Vol 52 (4) ◽  
pp. 746-752 ◽  
Author(s):  
M. A. Halcrow ◽  
H. R. Powell ◽  
M. J. Duer
Keyword(s):  
Hydrogen Bond ◽  
Nmr Spectroscopy ◽  
Solvate Water Molecule ◽  
X Ray ◽  
Nmr Data ◽  
Tautomeric Forms ◽  
Oxygen Donor ◽  
Intramolecular Hydrogen ◽  
Pyridinic N ◽  
C Nmr

The single-crystal X-ray structures of 3{5}-(2′,5′-dimethoxyphenyl)pyrazole (HI) and the hemihydrate of 3 {5}-(3/,4′-dimethoxyphenyl)pyrazole (IV) have been determined. Compound (HI) exists purely as the 5-substituted prototropomer in the crystal; the pyrazole pyrollic N—H proton is involved in a three-way hydrogen bond, involving an intramolecular contact with a methoxy oxygen donor and an intermolecular interaction to the pyridinic N atom of a neighbouring molecule, forming discrete hydrogen-bonded dimers. There is no evidence of degenerate proton transfer within the dimeric units from CPMAS 13C NMR spectroscopy, in contrast to other known pyrazoles that associate in this manner. In (IV).1/2H2O, however, the pyrrolic proton is disordered over both N(1) and N(2) via hydrogen bonding to the solvate water molecule. CPMAS 13C NMR spectroscopy shows that the prototropic disorder in (IV).1/2H2O is static at temperatures up to 370 K. Solution 1H and 13C NMR data in DMSO-d 6 show that for both (HI) and (IV) the 3- and 5-substituted tautomeric forms are similarly populated in this solvent, suggesting both that the intramolecular hydrogen bond in (HI) has been disrupted and that the two tautomers of (HI) and (IV) are close in energy.

1H NMR studies on the solution conformation of contulakin-G and analogues

2002 ◽  
Vol 80 (8) ◽  
pp. 1022-1031 ◽  
Author(s):  
Lill Kindahl ◽  
Corine Sandström ◽  
A Grey Craig ◽  
Thomas Norberg ◽  
Lennart Kenne
Keyword(s):  
Hydrogen Bond ◽  
Chemical Shifts ◽  
Torsional Rigidity ◽  
Peptide Chain ◽  
Random Coil ◽  
Amide Proton ◽  
Solution Conformation ◽  
Nmr Studies ◽  
H Nmr ◽  
Intramolecular Hydrogen

The conformation of contulakin-G, a bioactive 16 amino acid O-linked glycopeptide (ZSEEGGSNAT*KKPYIL) with the disaccharide β-D-Gal(1[Formula: see text]3)α-D-GalNAc attached to the threonine residue in position 10, has been investigated by 1H NMR spectroscopy. The 1H NMR data for the non-glycosylated peptide and for two glycopeptide analogues, one with the monosaccharide α-D-GalNAc at Thr10 and one with the disaccharide β-D-Gal(1–>3)α-D-GalNAc at Ser7, all of lower bioactivity than contulakin-G, have also been collected. The chemical shifts, NOEs, temperature coefficients of amide protons, and 3JNH,αH-values suggest that all four compounds exist mainly in random coil conformations. Some transient populations of folded conformations are also present in the glycopeptides and turns, probably induced by the sugars, are present in the peptide chain around the site of glycosylation. In the two peptides O-glycosylated at Thr10, the rotation of α-D-GalNAc around the linkage between the sugar and the peptide is restricted. There is evidence for a hydrogen bond between the amide proton of α-D-GalNAc and the peptide chain that could contribute to this torsional rigidity. An intramolecular hydrogen bond between the carbohydrate and the peptide chain does not exist in the peptide O-glycosylated at the Ser7 residue. Key words: conformation, contulakin-G, NMR, O-linked glycopeptide.

Crystal Structure and Tautomerism of 1-[N-(4-Iodophenyl)]aminomethylidene-2(1H)naphthalenone

2001 ◽  
Vol 56 (10) ◽  
pp. 1003-1008 ◽  
Author(s):  
H. Ünver ◽  
M. Kabak ◽  
D. M. Zengin ◽  
T. N. Durlu
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Quantum Mechanical ◽  
Monoclinic Space Group ◽  
Quantum Mechanical Calculations ◽  
X Ray ◽  
H Nmr ◽  
Mechanical Methods ◽  
Intramolecular Hydrogen ◽  
Semi Empirical

1-[N-(4-Iodophenyl)]aminomethylidene-2(1H)naphthalenone (1) (C17H12NOI) has been studied by X-ray analysis, IR, 1H NMR, UV and AM1 semi-empirical quantum mechanical methods. It crystallises in the monoclinic space group P21/n with a = 4.844(3), b = 21.428(2), c = 13.726(2) Å, ß = 93.07(2)° (R1 =0.032 for 4132 reflections [I > 2σ(I)]). The title compound is not planar and an intramolecular hydrogen bond connects O1 and N1 [2.530(4) Å]. Complementary IR, 1H NMR and UV measurements out. Tautomerism and conformations of the title semi-empirical quantum mechanical calculations and the results are compared with the X-ray data.

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