A new polymorphic form of bis(acetato-κO)bis[2-(pyridin-2-yl)ethanol-κ2N,O]nickel(II)

2012 ◽  
Vol 68 (12) ◽  
pp. m359-m362 ◽  
Author(s):  
Miha Trdin ◽  
Nina Lah
Keyword(s):  
Hydrogen Bond ◽  
Crystal Packing ◽  
Intermolecular Hydrogen Bond ◽  
Polymorphic Form ◽  
Side Chain ◽  
Hydrogen Bond Interaction ◽  
Acetate Complex ◽  
Polymorphic Forms ◽  
Packing Arrangement ◽  
Intramolecular Hydrogen

A new polymorph of a mononuclear nickel(II) acetate complex with 2-(pyridin-2-yl)ethanol ligands, [Ni(CH3COO)2(C7H9NO)2], has been prepared and structurally characterized. Its molecular structure resembles the structures of two previously reported polymorphs in that the NiIIatom is located on an inversion centre and is coordinated by pairs of acetate and 2-(pyridin-2-yl)ethanol ligands. The acetate anions are coordinated in a monodentate manner, while the 2-(pyridin-2-yl)ethanol ligands are coordinated in a bidentate chelating mode involving the endocyclic N atom and the hydroxy O atom of the ligand side chain. A strong bifurcated intramolecular hydrogen-bond interaction was observed involving the hydroxy O atom as donor and both acetate O atoms as acceptors. No classical intermolecular hydrogen-bond contacts were observed. However, the crystal packing is effected through π–π and C—H...π interactions, giving rise to a different packing arrangement. A brief comparison of the three polymorphic forms is presented.

Structure of Diastereomeric 10-Bromo-10,11-dihydroquinines

2002 ◽  
Vol 57 (5) ◽  
pp. 586-592 ◽  
Author(s):  
Teresa Borowiak ◽  
Grzegorz Dutkiewicz ◽  
Jacek Thiel
Keyword(s):  
Hydrogen Bond ◽  
Nitrogen Atom ◽  
Unusual Case ◽  
Crystal Packing ◽  
Intermolecular Hydrogen Bond ◽  
Cinchona Alkaloid ◽  
Side Chain ◽  
Hydrogen Bond Formation ◽  
The Common ◽  
Ring Open

The absolute configurations of new chiral centers in the side chains of diastereomeric 10,11-dihydroquinines, C20H25BrN2O2, have been determined. Both diastereomers with either 10R or 10S configuration adopt the conformations in which quinuclidine nitrogen atom points away from the quinoline ring (open conformations). The bulky C3-side chain in the 10R diastereomer hinders intermolecular hydrogen bond formation to the quinuclidinic, more basic nitrogen atom. Instead, the hydrogen bond to the quinolinic N atom is formed which is an unusual case for Cinchona alkaloid crystal packing. The same bulky C3-substituent in the 10S diastereomer does not hinder the common packing mode via intermolecular hydrogen bonding to the quinuclidinic N-atom.

scholarly journals Controlled usage of H/D exchange to circumvent concomitant polymorphs of ROY

IUCrJ ◽  
2018 ◽  
Vol 5 (5) ◽  
pp. 569-573 ◽  
Author(s):  
Jacqueline Falk ◽  
Detlef Hofmann ◽  
Klaus Merz
Keyword(s):  
Hydrogen Bond ◽  
Solid State ◽  
Intermolecular Hydrogen Bond ◽  
Simultaneous Formation ◽  
Structural Formation ◽  
Hydrogen Bond Strength ◽  
Polymorphic Forms ◽  
Amine Function ◽  
Intramolecular Hydrogen ◽  
Selective Formation

The hypothesis that H/D exchange affects the structural formation of organic compounds in the solid state is supported by a deeper understanding of the altering polymorphism of ROY (a substance striking for its high number of polymorphic forms) through deuteration. Therefore, ROY was deuterated at its amine function, which leads to a seemingly small yet effective modification of the hydrogen-bond strength. In contrast to the crystallization of the non-deuterated ROY in methanol or ethanol, which leads to the simultaneous formation of two forms (OP and Y polymorphs), so-called concomitant polymorphs, the crystallization of d 1-ROY leads to the selective formation of the Y polymorph exclusively. The preferred aggregation behavior of the Y form of d 1-ROY is assigned to the weakening of an intramolecular hydrogen bond and a consequently strengthened intermolecular hydrogen bond after deuteration.

Structures and properties of side-chain liquid crystalline polynorbornenes containing an amide group: hydrogen bonding interactions and spacer length effects

2020 ◽  
Vol 11 (29) ◽  
pp. 4749-4759
Author(s):  
Dong Shi ◽  
Wen-Ying Chang ◽  
Xiang-Kui Ren ◽  
Shuang Yang ◽  
Er-Qiang Chen
Keyword(s):  
Mechanical Properties ◽  
Hydrogen Bond ◽  
Liquid Crystalline ◽  
Amide Group ◽  
Self Organization ◽  
Side Chain ◽  
Hydrogen Bond Interaction ◽  
Spacer Length ◽  
Hydrogen Bonding Interactions ◽  
Structures And Properties

Side-chain liquid crystalline polynorbornenes based on benzanilide mesogens exhibit rich self-organization behaviours and enhanced mechanical properties owing to the lateral hydrogen bond interaction that can be tuned by the spacer length.

scholarly journals (2Z)-2-Bromo-3-[3,5-dibromo-4-(ethylamino)phenyl]-1-(2,4-dichlorophenyl)prop-2-en-1-one

2007 ◽  
Vol 63 (11) ◽  
pp. o4308-o4309 ◽  
Author(s):  
Ray J. Butcher ◽  
Jerry P. Jasinski ◽  
Anil N. Mayekar ◽  
B. Narayana ◽  
H. S. Yathirajan
Keyword(s):  
Hydrogen Bond ◽  
Molecular Conformation ◽  
Crystal Packing ◽  
Phenyl Group ◽  
Hydrogen Bond Interactions ◽  
Compound C ◽  
Propyl Ketone ◽  
Phenyl Rings ◽  
The Mean ◽  
Intramolecular Hydrogen

In the title compound, C17H12Br3Cl2NO, the mean planes of the 3,5-dibromo-4-phenyl and 2,4-dichlorophenyl groups make a dihedral angle of 72.4 (2)°. The dihedral angles between the 2-bromoprop-2-en-1-one group and the two phenyl ring groups (3,5-dibromo-4-phenyl and 2,4-dichlorophenyl) are 71.1 (1) and 10.9 (4)°, respectively. The crystal packing is stabilized by intermolecular N—H...O hydrogen-bond interactions between the ethylamino H atom and the propyl ketone O atom, with the 3,5-dibromo-4-phenyl rings linked in chains in an alternate inverted pattern parallel and oblique to the ac face and diagonally along the a axis of the unit cell. An intramolecular hydrogen bond between the ethyl amino H atom and the 5-Br atom from the 3,5-dibromo-4-phenyl group helps stabilize the molecular conformation.

P-Chiral, N-phosphoryl sulfonamide Brønsted acids with an intramolecular hydrogen bond interaction that modulates organocatalysis

2019 ◽  
Vol 17 (38) ◽  
pp. 8690-8694 ◽  
Author(s):  
Minglei Yuan ◽  
Ifenna I. Mbaezue ◽  
Zhi Zhou ◽  
Filip Topic ◽  
Youla S. Tsantrizos
Keyword(s):  
Hydrogen Bond ◽  
Intramolecular Hydrogen Bond ◽  
Transfer Hydrogenation ◽  
Bronsted Acids ◽  
Bronsted Acid ◽  
Brønsted Acid ◽  
Hydrogen Bond Interaction ◽  
Bond Interaction ◽  
Brönsted Acid ◽  
Intramolecular Hydrogen

An intramolecular H-bond in the Brønsted acid OttoPhosa I accelerates the reaction and increases enantioselectivity for the transfer hydrogenation of quinolines.

Intramolecular hydrogen bonds: common motifs, probabilities of formation and implications for supramolecular organization

2000 ◽  
Vol 56 (5) ◽  
pp. 849-856 ◽  
Author(s):  
Clair Bilton ◽  
Frank H. Allen ◽  
Gregory P. Shields ◽  
Judith A. K. Howard
Keyword(s):  
Hydrogen Bond ◽  
Bond Formation ◽  
Intermolecular Hydrogen Bond ◽  
The Other ◽  
Supramolecular Organization ◽  
Intermolecular Bond ◽  
Hydrogen Bond Formation ◽  
Ability To Act ◽  
Structural Database ◽  
Intramolecular Hydrogen

A systematic survey of the Cambridge Structural Database (CSD) has identified all intramolecular hydrogen-bonded ring motifs comprising less than 20 atoms with N and O donors and acceptors. The probabilities of formation Pm of the 50 most common motifs, which chiefly comprise five- and six-membered rings, have been derived by considering the number of intramolecular motifs which could possibly form. The most probable motifs (Pm > 85%) are planar conjugated six-membered rings with a propensity for resonance-assisted hydrogen bonding and these form the shortest contacts, whilst saturated six-membered rings typically have Pm < 10%. The influence of intramolecular-motif formation on intermolecular hydrogen-bond formation has been assessed for a planar conjugated model substructure, showing that a donor-H is considerably less likely to form an intermolecular bond if it forms an intramolecular one. On the other hand, the involvement of a carbonyl acceptor in an intramolecular bond does not significantly affect its ability to act as an intermolecular acceptor and thus carbonyl acceptors display a substantially higher inclination for bifurcation if one hydrogen bond is intramolecular.

scholarly journals 2-(3-{(3R,4R)-4-Methyl-3-[methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino]piperidin-1-yl}oxetan-3-yl)acetonitrile monohydrate

2014 ◽  
Vol 70 (4) ◽  
pp. o382-o383
Author(s):  
Matthias Gehringer ◽  
Ellen Pfaffenrot ◽  
Peter R. W. E. F. Keck ◽  
Dieter Schollmeyer ◽  
Stefan A. Laufer
Keyword(s):  
Hydrogen Bond ◽  
Water Molecule ◽  
Organic Molecules ◽  
Crystal Packing ◽  
Intermolecular Hydrogen Bond ◽  
Chair Conformation ◽  
Pyrimidine Ring ◽  
Piperidine Ring ◽  
Water Molecules ◽  
Compound C

In the title compound, C18H24N6O·H2O, the piperidine ring adopts a chair conformation with an N—C—C—C torsion angle of 39.5 (5)° between thecis-related substituents. The pyrrole N—H group forms a water-mediated intermolecular hydrogen bond to one of the N atoms of the annelated pyrimidine ring. The water molecule connects two organic molecules and is disorderd over two positions (occupancies of 0.48 and 0.52). The crystal packing shows zigzag chains of alternating organic and water molecules running parallel to theaaxis.

scholarly journals Relative substituent orientation in the structure ofcis-3-chloro-1,3-dimethyl-N-(4-nitrophenyl)-2-oxocyclopentane-1-carboxamide

2014 ◽  
Vol 70 (9) ◽  
pp. 121-123
Author(s):  
Matthias Zeller ◽  
Jonas Warneke ◽  
Vladimir Azov
Keyword(s):  
Hydrogen Bond ◽  
Crystal Packing ◽  
Membered Ring ◽  
Amide Group ◽  
Aromatic Rings ◽  
Methyl Group ◽  
Compound C ◽  
The Mean ◽  
Graph Set ◽  
Intramolecular Hydrogen

The structure of the title compound, C14H15ClN2O4, prepared by reaction of a methacryloyl dimer with nitroaniline, was determined to establish the relative substituent orientation on the cyclopentanone ring. In agreement with an earlier proposed reaction mechanism, the amide group and the methyl group adjacent to the chloro substituent adopt equatorial positions and relativecisorientation, whereas the Cl substituent itself and the methyl group adjacent to the amide have axial orientations relative to the mean plane of the five-membered ring. The conformation of the molecule is stabilized by one classical N—H...O (2.18 Å) and one non-classical C—H...O (2.23 Å) hydrogen bond, each possessing anS(6) graph-set motif. The crystal packing is defined by several non-classical intramolecular hydrogen bonds, as well as by partial stacking of the aromatic rings.

A water wire inL-prolyl-L-serine monohydrate

2013 ◽  
Vol 69 (5) ◽  
pp. 556-559 ◽  
Author(s):  
Carl Henrik Görbitz ◽  
Vitthal N. Yadav
Keyword(s):  
Title Compound ◽  
Functional Group ◽  
Crystal Packing ◽  
Side Chain ◽  
Propanoic Acid ◽  
Water Molecules ◽  
Packing Arrangement ◽  
Hydroxy Groups ◽  
Hydrogen Bonded

Despite the extra functional group in the serine side chain, the crystal packing arrangement of the title compound {systematic name: (S)-3-hydroxy-2-[(S)-pyrrolidine-2-carboxamido]propanoic acid monohydrate}, C8H14N2O4·H2O, is essentially the same as observed for a series of L-Pro-L-Nop peptide hydrates, where Nop is a strictly nonpolar residue. This is rendered possible by a monoclinicP21packing arrangement withZ′ = 2 that deviates from orthorhombicP212121symmetry only for the seryl hydroxy groups, which form infinite O—H...O—H hydrogen-bonded chains along the 5.3 Åaaxis. At the same time, cocrystallized water molecules form parallel water wires.

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