scholarly journals Polymorphism, Hydrogen Bond Properties, and Vibrational Structure of 1H-Pyrrolo[3,2-h]Quinoline Dimers

2012 ◽  
Vol 2012 ◽  
pp. 1-11 ◽  
Author(s):  
Alexandr Gorski ◽  
Sylwester Gawinkowski ◽  
Roman Luboradzki ◽  
Marek Tkacz ◽  
Randolph P. Thummel ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Raman Spectra ◽  
Bond Formation ◽  
Vibrational Structure ◽  
Hydrogen Bond Donor ◽  
Intermolecular Hydrogen Bonds ◽  
Hydrogen Bond Formation ◽  
Bifunctional Molecule ◽  
Donor And Acceptor ◽  
Ir And Raman

Two forms of cyclic, doubly hydrogen-bonded dimers are discovered for crystalline 1H-pyrrolo[3,2-h]quinoline, a bifunctional molecule possessing both hydrogen bond donor and acceptor groups. One of the forms is planar, the other is twisted. Analysis of IR and Raman spectra, combined with DFT calculations, allows one to assign the observed vibrations and to single out vibrational transitions which can serve as markers of hydrogen bond formation and dimer structure. Raman spectra measured for samples submitted to high pressure indicate a transition from the planar towards the twisted structure. Formation of intermolecular hydrogen bonds leads to a large increase of the Raman intensity of the NH stretching band: it can be readily observed for the dimer, but is absent in the monomer spectrum.

A 2′-deoxycytidine long-linker click adduct forming two conformers in the asymmetric unit

2012 ◽  
Vol 68 (4) ◽  
pp. o174-o178 ◽  
Author(s):  
Frank Seela ◽  
Hai Xiong ◽  
Simone Budow ◽  
Henning Eickmeier ◽  
Hans Reuter
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Title Compound ◽  
Crystalline State ◽  
Bond Formation ◽  
Three Dimensional ◽  
Sugar Residue ◽  
Asymmetric Unit ◽  
Intermolecular Hydrogen Bonds ◽  
Hydrogen Bond Formation

The title compound {systematic name: 4-amino-1-(2-deoxy-β-D-erythro-pentofuranosyl)-5-[6-(1-benzyl-1H-1,2,3-triazol-4-yl)hex-1-ynyl]pyrimidin-2(1H)-one}, C24H28N6O4, shows two conformations in the crystalline state,viz.(I-1) and (I-2). The pyrimidine groups and side chains of the two conformers are almost superimposable, while the greatest differences between them are observed for the sugar groups. The N-glycosylic bonds of both conformers adopt similaranticonformations, with χ = −168.02 (12)° for conformer (I-1) and χ = −159.08 (12)° for conformer (I-2). The sugar residue of (I-1) shows anN-type (C3′-endo) conformation, withP= 33.1 (2)° and τm= 29.5 (1)°, while the conformation of the 2′-deoxyribofuranosyl group of (I-2) isS-type (C3′-exo), withP = 204.5 (2)° and τm= 33.8 (1)°. Both conformers participate in hydrogen-bond formation and exhibit identical patterns resulting in three-dimensional networks. Intermolecular hydrogen bonds are formed with neighbouring molecules of different and identical conformations (N—H...N, N—H... O, O—H...N and O—H...O).

scholarly journals Crystallographic study of self-organization in the solid state including quasi-aromatic pseudo-ring stacking interactions in 1-benzoyl-3-(3,4-dimethoxyphenyl)thiourea and 1-benzoyl-3-(2-hydroxypropyl)thiourea

2017 ◽  
Vol 73 (1) ◽  
pp. 52-56 ◽  
Author(s):  
Andrzej Okuniewski ◽  
Damian Rosiak ◽  
Jarosław Chojnacki ◽  
Barbara Becker
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Strong Hydrogen Bond ◽  
Compound I ◽  
Hydrogen Bond Donor ◽  
Hydrogen Bond Formation ◽  
Oh Groups ◽  
Space Group ◽  
Donor And Acceptor ◽  
Phenyl Rings

1-Benzoylthioureas contain both carbonyl and thiocarbonyl functional groups and are of interest for their biological activity, metal coordination ability and involvement in hydrogen-bond formation. Two novel 1-benzoylthiourea derivatives, namely 1-benzoyl-3-(3,4-dimethoxyphenyl)thiourea, C16H16N2O3S, (I), and 1-benzoyl-3-(2-hydroxypropyl)thiourea, C11H14N2O2S, (II), have been synthesized and characterized. Compound (I) crystallizes in the space group P\overline{1}, while (II) crystallizes in the space group P21/c. In both structures, intramolecular N—H...O hydrogen bonding is present. The resulting six-membered pseudo-rings are quasi-aromatic and, in each case, interact with phenyl rings via stacking-type interactions. C—H...O, C—H...S and C—H...π interactions are also present. In (I), there is one molecule in the asymmetric unit. Pairs of molecules are connected via two intermolecular N—H...S hydrogen bonds, forming centrosymmetric dimers. In (II), there are two symmetry-independent molecules that differ mainly in the relative orientations of the phenyl rings with respect to the thiourea cores. Additional strong hydrogen-bond donor and acceptor –OH groups participate in the formation of intermolecular N—H...O and O—H...S hydrogen bonds that join molecules into chains extending in the [001] direction.

Defining the hydrogen bond: An account (IUPAC Technical Report)

2011 ◽  
Vol 83 (8) ◽  
pp. 1619-1636 ◽  
Author(s):  
Elangannan Arunan ◽  
Gautam R. Desiraju ◽  
Roger A. Klein ◽  
Joanna Sadlej ◽  
Steve Scheiner ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Bond Formation ◽  
Blue Shift ◽  
Hydrogen Bond Donor ◽  
Hydrogen Bond Acceptor ◽  
Hydrogen Bond Formation ◽  
Technical Report ◽  
Definition Of ◽  
Covalent Nature

The term “hydrogen bond” has been used in the literature for nearly a century now. While its importance has been realized by physicists, chemists, biologists, and material scientists, there has been a continual debate about what this term means. This debate has intensified following some important experimental results, especially in the last decade, which questioned the basis of the traditional view on hydrogen bonding. Most important among them are the direct experimental evidence for a partial covalent nature and the observation of a blue-shift in stretching frequency following X–H···Y hydrogen bond formation (XH being the hydrogen bond donor and Y being the hydrogen bond acceptor). Considering the recent experimental and theoretical advances, we have proposed a new definition of the hydrogen bond, which emphasizes the need for evidence. A list of criteria has been provided, and these can be used as evidence for the hydrogen bond formation. This list is followed by some characteristics that are observed in typical hydrogen-bonding environments.

Vapochromism induced by intermolecular electron transfer coupled with hydrogen-bond formation in zinc dithiolene complex

2020 ◽  
Vol 8 (42) ◽  
pp. 14939-14947
Author(s):  
So Yokomori ◽  
Shun Dekura ◽  
Tomoko Fujino ◽  
Mitsuaki Kawamura ◽  
Taisuke Ozaki ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Electron Transfer ◽  
Bond Formation ◽  
Intermolecular Electron Transfer ◽  
Hydrogen Bond Formation ◽  
Complex Crystal

A novel vapochromic mechanism by intermolecular electron transfer coupled with hydrogen-bond formation was realized in a zinc dithiolene complex crystal.

Diverse mechanisms of carbon-hydrogen bond formation through binuclear reductive elimination reactions

1982 ◽  
Vol 104 (2) ◽  
pp. 619-621 ◽  
Author(s):  
Mario J. Nappa ◽  
Roberto Santi ◽  
Steven P. Diefenbach ◽  
Jack Halpern
Keyword(s):  
Hydrogen Bond ◽  
Bond Formation ◽  
Reductive Elimination ◽  
Hydrogen Bond Formation ◽  
Elimination Reactions

Theoretical analysis of the (HNO)2, (HNO···HNS), and (HNS)2 dimers — A case of red and blue shifts of N–H stretching frequency

2010 ◽  
Vol 88 (8) ◽  
pp. 849-857 ◽  
Author(s):  
Nguyen Tien Trung ◽  
Tran Thanh Hue ◽  
Minh Tho Nguyen
Keyword(s):  
Hydrogen Bond ◽  
Quantum Chemical ◽  
Bond Formation ◽  
Blue Shift ◽  
Proton Donor ◽  
Basis Sets ◽  
Coupled Cluster ◽  
Hydrogen Bond Formation ◽  
Length Contraction ◽  
Moller Plesset

The hydrogen-bonded interactions in the simple (HNZ)2 dimers, with Z = O and S, were investigated using quantum chemical calculations with the second-order Møller–Plesset perturbation (MP2), coupled-cluster with single, double (CCSD), and triple excitations (CCSD(T)) methods in conjunction with the 6-311++G(2d,2p), aug-cc-pVDZ, and aug-cc-pVTZ basis sets. Six-membered cyclic structures were found to be stable complexes for the dimers (HNO)2, (HNS)2, and (HNO–HNS). The pair (HNS)2 has the largest complexation energy (–11 kJ/mol), and (HNO)2 the smallest one (–9 kJ/mol). A bond length contraction and a frequency blue shift of the N–H bond simultaneously occur upon hydrogen bond formation of the N–H···S type, which has rarely been observed before. The stronger the intramolecular hyperconjugation and the lower the polarization of the X–H bond involved as proton donor in the hydrogen bond, the more predominant is the formation of a blue-shifting hydrogen bond.

Internal Hydrogen Bond Formation in a syn-Hydroxyepoxide

Science ◽  
1982 ◽  
Vol 215 (4533) ◽  
pp. 695-696 ◽  
Author(s):  
J. P. GLUSKER ◽  
D. E. ZACHARIAS ◽  
D. L. WHALEN ◽  
S. FRIEDMAN ◽  
T. M. POHL
Keyword(s):  
Hydrogen Bond ◽  
Bond Formation ◽  
Hydrogen Bond Formation ◽  
Internal Hydrogen ◽  
Internal Hydrogen Bond

Influence of Hydrogen Bond Formation on the Photophysics ofN-(2,6-Dimethylphenyl)-2,3-naphthalimide

2004 ◽  
Vol 108 (19) ◽  
pp. 4357-4364 ◽  
Author(s):  
Attila Demeter ◽  
László Ravasz ◽  
Tibor Bérces
Keyword(s):  
Hydrogen Bond ◽  
Bond Formation ◽  
Hydrogen Bond Formation
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