scholarly journals Crystal structure of 3-[({2-[bis(2-hydroxybenzyl)amino]ethyl}(2-hydroxybenzyl)amino)methyl]-2-hydroxy-5-methylbenzaldehyde

2014 ◽  
Vol 70 (12) ◽  
pp. 562-565
Author(s):  
Alexandra S. Fonseca ◽  
Adailton J. Bortoluzzi
Keyword(s):  
Molecular Structure ◽  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Intramolecular Hydrogen Bond ◽  
Intermolecular Hydrogen Bond ◽  
Phenol Group ◽  
The Third ◽  
Graph Set ◽  
Title Molecule ◽  
Intramolecular Hydrogen

The non-symmetric title molecule, C32H34N2O5, is based on a tetrasubstituted ethylenediamine backbone. The molecular structure consists of three hydroxybenzyl groups and one 2-hydroxy-5-methylbenzaldehyde group bonded to the N atoms of the diamine unit. The ethylenediamine skeleton shows a regular extended conformation, while the spatial orientation of the phenol arms is governed by hydrogen bonds. In the 2-hydroxy-5-methylbenzaldehyde group, an intramolecularS(6) O—H...O hydrogen bond is observed between the alcohol and aldehyde functions, and the neighbouring phenol arm participates in an intramolecularS(6) O—H...N hydrogen bond. The third phenol group is involved in a bifurcated intramolecular hydrogen bond with graph-set notationS(6) for O—H...N and O—H...O intramolecular hydrogen bonds between neighbouring amine and phenol arms, respectively. Finally, the fourth phenol group acts as an acceptor in a bifurcated intramolecular hydrogen bond and also acts as donor in an intermolecular hydrogen bond, which connects inversion-related molecules into dimers withR44(8) ring motifs.

Ethyl 1-[5-amino-1-tert-butyl-3-(methylsulfanyl)-1H-pyrazole-4-carbonyl]-5-methyl-3-(methylsulfanyl)-1H-pyrazole-4-carboxylate

2006 ◽  
Vol 62 (5) ◽  
pp. o1679-o1681
Author(s):  
Jun-Fei Li ◽  
Hai-Bin Song ◽  
You-Quan Zhu ◽  
Hua-Zheng Yang
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Intramolecular Hydrogen Bond ◽  
Membered Ring ◽  
Intermolecular Hydrogen Bonds ◽  
Tert Butyl ◽  
The Family ◽  
Title Molecule ◽  
Intramolecular Hydrogen

The title molecule, C17H25N5O3S2, belongs to the family of bis-heterocycles. In the crystal structure, there are one intra- and two intermolecular hydrogen bonds. One of the two pyrazole rings and the six-membered ring formed by the intramolecular hydrogen bond are approximately coplanar.

scholarly journals C–H⋯F Hydrogen Bond and Integral Intensities of Vinyl C–H Vibtations in Push-Pull β-Dimethylaminotrifluoromethyl Ketone and Its Deuterated Analog

2013 ◽  
Vol 2013 ◽  
pp. 1-13 ◽  
Author(s):  
Sergei Vdovenko ◽  
Igor Gerus ◽  
Elena Fedorenko ◽  
Valery Kukhar
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Dft Calculations ◽  
Intramolecular Hydrogen Bond ◽  
Infrared Spectra ◽  
Intermolecular Hydrogen Bond ◽  
Intermolecular Hydrogen Bonds ◽  
Accurate Analysis ◽  
Deuterated Analog ◽  
Intramolecular Hydrogen

The accurate analysis of infrared spectra (both wavenumbers and intensities) of (E)-4-(dimethylamino)-1,1,1-trifluorobut-3-en-2-one (DMTBN) and (E)-4-(hexadeutero-dimethylamino)-1,1,1-trifluorobut-3-en-2-one (d6-DMTBN) revealed that besides intramolecular hydrogen bond in the (EE) conformer, these enaminoketones form cyclic dimers between the (EZ) and (EE) conformers due to intermolecular hydrogen bonds, namely, O=C and . Evaluation of constant and enthalpy of formation of these H-bonds revealed that O=C bond has greater and more negative than bond (cf. 214.4 M−1, −21.7 kJ M−1dm3, and 16.4 M−1, −6.7 kJ M−1dm3, resp.). Consequently, stronger H-bond ⋯O=C is formed in the first place, whereas weaker H-bond is formed afterward. Moreover, formation of intermolecular hydrogen bond has influence on C–F vibrations, but analysis of this influence must take into account the fact that these vibrations in some cases are coupled with . True enthalpy of the equilibrium (EZ)⇌(EE) is positive (25.3 kJ M−1dm3), thus confirming results of DFT calculations, according to which the (EZ) conformer is more stable than the (EE) one.

Stereochemistry-dependent hydrogen bonds stabilise stacked conformations in jet-cooled cyclic dipeptides: (LD) vs. (LL) cyclo tyrosine–tyrosine

2018 ◽  
Vol 212 ◽  
pp. 399-419 ◽  
Author(s):  
Feriel BenNasr ◽  
Ariel Pérez-Mellor ◽  
Ivan Alata ◽  
Valeria Lepere ◽  
Nejm-Eddine Jaïdane ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Intramolecular Hydrogen Bond ◽  
Cyclic Dipeptides ◽  
Intramolecular Hydrogen

Changing the chirality of one residue prevents the formation of an OH⋯O intramolecular hydrogen bond in cyclo di-tyrosine.

Intramolecular hydrogen bond-induced high chemical stability of metal–organic frameworks

2020 ◽  
Vol 7 (19) ◽  
pp. 3548-3554
Author(s):  
Keke Wang ◽  
Qunmin Wang ◽  
Xiong Wang ◽  
Mei Wang ◽  
Qin Wang ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Intramolecular Hydrogen Bond ◽  
Chemical Stability ◽  
Metal Organic Frameworks ◽  
Carboxyl Groups ◽  
High Chemical ◽  
Metal Organic ◽  
Intramolecular Hydrogen ◽  
High Chemical Stability

Intramolecular hydrogen bonds in ligands restrict the rotation of carboxyl groups and consequently enhance the chemical stability of MOFs.

Electronic absorption spectra of nitroanilines

1979 ◽  
Vol 44 (5) ◽  
pp. 1613-1618 ◽  
Author(s):  
Viktor Řehák ◽  
Vladimír Kadeřábek
Keyword(s):  
Molecular Structure ◽  
Hydrogen Bond ◽  
Absorption Spectra ◽  
Intramolecular Hydrogen Bond ◽  
Electronic Absorption ◽  
Electronic Absorption Spectra ◽  
Electronic System ◽  
Intramolecular Hydrogen ◽  
Absorption Transitions

Electronic absorption spectra of N-alkyl and N-arylsubstituted 2,4-dinitro- and 2,6-dinitroanilines are discussed in the terms of energy and intensity of the energetically lowest absorption transitions and molecular structure (intramolecular hydrogen bond, sterical effects, hyperconjugation and increase of the π-electronic system of the molecule.

True symmetry or pseudosymmetry: 5-amino-1-(4-methylphenylsulfonyl)-4-pyrazolin-3-one and a comparison with its 1-phenylsulfonyl analogue

2012 ◽  
Vol 69 (1) ◽  
pp. 90-92 ◽  
Author(s):  
Galal H. Elgemeie ◽  
Shahinaz H. Sayed ◽  
Peter G. Jones
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Intramolecular Hydrogen Bond ◽  
Title Compound ◽  
Acta Cryst ◽  
Interplanar Angle ◽  
Phenyl Derivative ◽  
Compound C ◽  
Independent Molecules ◽  
Intramolecular Hydrogen

The title compound, C10H11N3O3S, (I), crystallizes as the NH tautomer. The two rings subtend an interplanar angle of 72.54 (4)°. An intramolecular hydrogen bond is formed from the NH2group to a sulfonyl O atom. The molecular packing involves layers of molecules parallel to thebcplane atx≃ 0, 1etc., with two classical linear hydrogen bonds (amino–sulfonyl and pyrazoline–carbonyl N—H...O) and a further interaction (amino–sulfonyl N—H...O) completing a three-centre system with the intramolecular contact. The analogous phenyl derivative, (II) [Elgemeie, Hanfy, Hopf & Jones (1998).Acta Cryst.C54, 136–138], crystallizes with essentially the same unit cell and packing pattern, but with two independent molecules that differ significantly in the orientation of the phenyl groups. The space group isP21/cfor (I) butP21for (II), which is thus a pseudosymmetric counterpart of (I).

1-(4-Chlorophenyl)-4-(2-furoyl)-3-(2-furyl)-1H-pyrazol-5-ol

2007 ◽  
Vol 63 (3) ◽  
pp. o1289-o1290 ◽  
Author(s):  
Jin-Zhou Li ◽  
Heng-Qiang Zhang ◽  
Hong-Xin Li ◽  
Pi-Zhi Che ◽  
Tian-Chi Wang
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Title Compound ◽  
Intermolecular Hydrogen Bond ◽  
Hydroxyl Groups ◽  
Intermolecular Hydrogen Bonds ◽  
Compound C ◽  
Graph Set

The crystal structure of the title compound, C18H11ClN2O4, contains intra- and intermolecular hydrogen bonds that link the ketone and hydroxyl groups. The intermolecular hydrogen bond results in the formation of a dimer with an R 2 2(12) graph-set motif.

Intra- and inter-molecular hydrogen bonding in diphytanylglycerol phospholipids: an infrared spectroscopic investigation

1990 ◽  
Vol 68 (1) ◽  
pp. 266-273 ◽  
Author(s):  
L. C. Stewart ◽  
M. Kates ◽  
P. W. Yang ◽  
H. H. Mantsch
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Hydrogen Bonds ◽  
Intramolecular Hydrogen Bond ◽  
Membrane Lipids ◽  
Head Group ◽  
Exact Nature ◽  
Oh Groups ◽  
Intramolecular Hydrogen ◽  
Phosphate Groups

A series of diphytanylglycerol phospholipids, i.e., diphytanylglycerol phosphate (PA), diphytanylglycerol phosphoglycerophosphate (PGP), the tri- and tetra-methyl derivatives of PGP, and the 2-deoxyglycerol analogue of PGP (dPGP) were studied by Fourier transform infrared spectroscopy. The use of the "deoxy" and methylated analogues of PGP, as well as that of PA and PGP of varying degrees of ionization, allowed the assignment of characteristic infrared bands associated with the phosphate groups. Analysis of these phosphate bands showed that at neutral pH, each of the two phosphate moieties in PGP is singly ionized, whereas in dPGP the phosphomonoester is doubly ionized. This is a consequence of the marked increase in the pK of one of the P-OH groups on the terminal phosphate of PGP (pK > 11), owing to the formation of an intramolecular hydrogen bond between the head group glycerol hydroxyl and the phosphate groups of PGP. Such an intramolecular hydrogen bond can not be formed by the dPGP analogue, and thus both negative charges in dPGP are located at the terminal phosphomonoester group. The O=P—OH groups of PGP also forms a network of intermolecular hydrogen bonds, the exact nature of which depends on concentration and degree of ionization. The possibility of a complex network of hydrogen bonds within (intramolecular) and between (intermolecular) anionic membrane lipids such as that found in PGP, is consistent with the hypothesis that these lipids function as proton-conducting pathways in membranes.Key words: phospholipids, infrared, hydrogen bonding, phosphatidylglycerophosphate, 2-deoxyphosphatidylglycerophosphate.

Temperature dependence of chemical shifts of protons in hydrogen bonds. Experimental evidence on an intramolecular hydrogen bond

1968 ◽  
Vol 46 (17) ◽  
pp. 2865-2868 ◽  
Author(s):  
T. Schaefer ◽  
G. Kotowycz
Keyword(s):  
Hydrogen Bond ◽  
Carbon Tetrachloride ◽  
Chemical Shift ◽  
Hydrogen Bonds ◽  
Temperature Dependence ◽  
Intramolecular Hydrogen Bond ◽  
Chemical Shifts ◽  
Hydroxyl Proton ◽  
Intramolecular Hydrogen ◽  
Strong Intramolecular Hydrogen Bond

A temperature dependence of the chemical shift of the hydroxyl proton in the strong intramolecular hydrogen bond in 3,5-dichlorosalicylaldehyde is observed in carbon tetrachloride and benzene-d6 solutions. Its magnitude of 0.25 to 0.30 × 10−2 p.p.m. per ° C over a range of 100 °C is in agreement with the model described by Muller and Reiter (1).

scholarly journals N-Benzyl-4-hydroxy-2-methyl-1,1-dioxo-2H-1λ6,2-benzothiazine-3-carboxamide

2012 ◽  
Vol 68 (6) ◽  
pp. o1921-o1921 ◽  
Author(s):  
Farhana Aman ◽  
Waseeq Ahmad Siddiqui ◽  
Adnan Ashraf ◽  
Hamid Latif Siddiqui ◽  
Masood Parvez
Keyword(s):  
Molecular Structure ◽  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Three Dimensional ◽  
Chair Conformation ◽  
Aromatic Rings ◽  
Dimensional Network ◽  
Thiazine Ring ◽  
The Mean ◽  
Title Molecule

In the title molecule, C17H16N2O4S, the heterocyclic thiazine ring adopts a half-chair conformation, with the S and N atoms displaced by 0.546 (4) and 0.281 (4) Å, respectively, on opposite sides of the mean plane formed by the remaining ring atoms. The molecular structure is stabilized by an intramolecular O—H...O hydrogen bond. The two aromatic rings are inclined to one another by 42.32 (11)°. In the crystal, molecules are linked by pairs of N—H...O hydrogen bonds, forming inversion dimers. The dimers are linked via a series of C—H...O interactions, leading to the formation of a three-dimensional network.

Sign in / Sign up

Export Citation Format

Share Document