Intramolecular hydrogen bonding in dichlorotetrakis(pyrazole-N2)nickel(II) as studied by low-temperature neutron diffraction, X-ray diffraction and infrared spectroscopy

1987 ◽  
Vol 43 (2) ◽  
pp. 226-229 ◽  
Author(s):  
R. B. Helmholdt ◽  
W. Hinrichs ◽  
J. Reedijk
Keyword(s):  
Hydrogen Bonding ◽  
Infrared Spectroscopy ◽  
Low Temperature ◽  
Neutron Diffraction ◽  
Intramolecular Hydrogen Bonding ◽  
X Ray Diffraction ◽  
X Ray ◽  
Intramolecular Hydrogen

Photochemical isomerization of 7-aryl-substituted 1H-Azepin-2(3H)-ones. Formation and X-ray structure determination of atropisomeric ketimines

1983 ◽  
Vol 36 (10) ◽  
pp. 2073 ◽  
Author(s):  
H Becker ◽  
BW Skelton ◽  
AH White
Keyword(s):  
Hydrogen Bonding ◽  
Structure Determination ◽  
Intramolecular Hydrogen Bonding ◽  
Phenolic Hydroxyl ◽  
X Ray Diffraction ◽  
X Ray ◽  
Photochemical Isomerization ◽  
Intramolecular Hydrogen

The structures of two isomeric 3,5-di-t-butyl-2-[(3,5-di-t-butyl-2-hydroxyphenyl){(Z)-methylimino}- methyl]cyclopent-2-en-1-ones, formed upon photoexcitation of 3,5-di-t-butyl-7-(3,5-di-t-butyl-2- hydroxyphenyl)-1-methyl-1H-azepin-2(3H)-one in methanol, have been established by X-ray diffraction, and are found to be examples of atropisomeric ketimines. In both isomers, the geometry of imino substitution is characterized by intramolecular hydrogen bonding with the phenolic hydroxyl.

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 A trigonal coordination of Au(I) phosphane complexes stabilized by O–H⋯X (X = Cl–, Br–, I–) interactions

2021 ◽  
Author(s):  
Petra Gründlinger ◽  
Cezarina Cela Mardare ◽  
Thorsten Wagner ◽  
Uwe Monkowius
Keyword(s):  
Hydrogen Bonding ◽  
Carboxylic Acid ◽  
Hydrogen Bonds ◽  
Intramolecular Hydrogen Bonding ◽  
Molecular Structures ◽  
X Ray Diffraction ◽  
X Ray ◽  
Standard Linear ◽  
Intramolecular Hydrogen ◽  
Linear Coordination

AbstractIn this work, we show that intramolecular hydrogen bonding can be used to stabilize tri-coordinated phosphane-gold(I) complexes. Two molecular structures of 2-(diphenylphosphino)benzoic acid (L) coordinated to a gold(I) atom were determined by single-crystal X-ray diffraction. The linear L–Au–Br shows a standard linear coordination and dimerizes via hydrogen bonds of the carboxylic acid. Upon addition of two additional phosphane ligands the complex [L3Au]X is formed which is stabilized by three intramolecular –C(O)O–H…X hydrogen bonds as proven by the X-ray structure of the respective chlorido-complex. X-ray powder diffractograms suggest the same structure also for X– = Br– and I–. Graphic abstract

Hétérocycles à fonction quinone. V. Réaction anormale de la butanedione avec la diamino-1,2 anthraquinone; structure cristalline de la naphto [2,3-f] quinoxalinedione-7,12 obtenue

1984 ◽  
Vol 62 (3) ◽  
pp. 526-530 ◽  
Author(s):  
Michel Baron ◽  
Sylviane Giorgi-Renault ◽  
Jean Renault ◽  
Patrick Mailliet ◽  
Daniel Carré ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Direct Method ◽  
Intramolecular Hydrogen Bonding ◽  
Unit Cell ◽  
Principal Characteristic ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cell Dimensions ◽  
Intramolecular Hydrogen ◽  
Unit Cell Dimensions

Butanedione reacts on heating with 1,2-diaminoanthraquinone to give, not the expected 2,3-dimethyl-naphtho[2,3-f]quinoxaline-7,12-dione 3, but 2-(2-hydroxy-2-methyl-3-oxobutyl)-3-methylnaphtho[2,3-f]quinoxaline-7,12-dione 4a whose structure was established by X-ray diffraction. This compound crystallizes in the triclinic [Formula: see text] space group with unit cell dimensions of a = 9.091 (1), b = 16.966 (4), c = 12.375 (3) Å; α = 100.75 (2), β = 101.83 (2), γ = 100.29 (2)°, V = 1789 Å3, Z = 4. The structure was resolved by the direct method and refined to R = 0.039 for 3027 independent reflections. The overall conformation of the molecule is essentially planar. The principal characteristic is the presence of two cyclic arrangements caused by intramolecular hydrogen bonding. 2,3-Dimethylnaphtho[2,3-f]quinoxaline-7,12-dione is the intermediate in this reaction.

Three-center intramolecular hydrogen bonding in oxamide derivatives. NMR and X-ray diffraction study

1998 ◽  
pp. 401-406 ◽  
Author(s):  
F. J. Martínez-Martínez ◽  
I. I. Padilla-Martínez ◽  
M. A. Brito ◽  
E. D. Geniz ◽  
R. C. Rojas ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Diffraction Study ◽  
Intramolecular Hydrogen Bonding ◽  
X Ray Diffraction ◽  
X Ray ◽  
Intramolecular Hydrogen

Molecular Cocrystals of Carboxylic Acids. XXVI Adducts of the Amino-Substituted Benzoic Acids with Nitroaromatic Lewis Bases: the Influence of Associative Polyfunctional Substituents on Self-Assembly of Molecules in Cocrystallization Processes

1997 ◽  
Vol 50 (10) ◽  
pp. 977 ◽  
Author(s):  
Daniel E. Lynch ◽  
Graham Smith ◽  
Karl A. Byriel ◽  
Colin H. L. Kennard
Keyword(s):  
Hydrogen Bonding ◽  
Infrared Spectroscopy ◽  
Self Assembly ◽  
Benzoic Acids ◽  
Aminobenzoic Acid ◽  
X Ray Diffraction ◽  
X Ray ◽  
Lewis Bases ◽  
Aminobenzoic Acids ◽  
Substituted Benzoic Acids

A series of molecular adducts of the isomeric aminobenzoic acids with the nitro-substituted Lewis bases 2-chloro-5-nitropyridine, 5-nitroquinoline and 5-nitroisoquinoline has been prepared and characterized by using infrared spectroscopy and X-ray powder diffraction, and in four cases by single-crystal X-ray diffraction methods. These four compounds are the adducts of 3-aminobenzoic acid with 5-nitroquinoline [(C7H7NO2)(C9H6N2O2)], 4-aminobenzoic acid with 5-nitroquinoline [(C7H7NO2)2(C9H6N2O2)], 2-aminobenzoic acid with 5-nitroisoquinoline [(C7H7NO2)(C9H6N2O2)] and 4-aminobenzoic acid with 5-nitroisoquinoline [(C7H7N2O2)(C9H6N2O2)]. Other compounds described are the (1 : 1) adducts of 4-aminobenzoic acid with 2-chloro-5-nitropyridine, and 2-aminobenzoic acid with 5-nitroquinoline. All adducts involve hydrogen-bonding network associations while in none of the examples is any proton transfer involved.

Structure and Conformations of Gaba-Transaminase Inhibitors. I. Multisubstrate Analogs

1986 ◽  
Vol 39 (10) ◽  
pp. 1559
Author(s):  
PR Andrews ◽  
V Cody ◽  
MN Iskander ◽  
AI Jeffrey ◽  
MF Mackay ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Transition State ◽  
Intramolecular Hydrogen Bonding ◽  
Side Chain ◽  
Gaba Transaminase ◽  
X Ray ◽  
Potential Energy Calculations ◽  
Phenolic Oxygen ◽  
Structural Differences ◽  
Intramolecular Hydrogen

Two multisubstrate analogues of the transition state in the reaction catalysed by the enzyme GABA- transaminase (E.C. 2.6.1.19), sulfonic acid pyridoxal dervative , C10H16N2O5S (1) and carboxylic acid pyridoxal derivative, C13H18N2O4 (2), have been characterized by X-ray analyses of crystals of (1). HCl , (1).H2O and (2). HCl . In each structure, the nitrogen on the side chain is the donor in intramolecular hydrogen bonding. However, it is only in (2). HCl that this interaction is with the phenolic oxygen as postulated in the proposed transition state of the reaction catalysed by GABA- transaminase . For both structures of (1), on the other hand, this interaction is with the oxygen of the ring hydroxymethyl substituent, and results in a seven- membered ring. Conformational analysis indicates that both modes of hydrogen bonding may be present in the pyridoxal derivatives, although no quantitative assessment is possible at the MINDO/3 or MNDO levels. Simple classical potential energy calculations indicate significant structural differences between the lowest energy conformations of these compounds and the calculated transition state. However, conformations which match the key features of the transition state are also relatively low in energy.

Sign in / Sign up

Export Citation Format

Share Document