Crystal structures of (E)-2-(2-benzylidenehydrazinyl)quinoxalines: persistent N–H···N intermolecular hydrogen bonds but variable π···π interactions

Author(s):  
Marcus V.N. de Souza ◽  
Thais C.M. Noguiera ◽  
Solange M.S.V. Wardell ◽  
James L. Wardell
2019 ◽  
Vol 234 (1) ◽  
pp. 59-71 ◽  
Author(s):  
Ligia R. Gomes ◽  
John N. Low ◽  
Nathasha R. de L. Correira ◽  
Thais C.M. Noguiera ◽  
Alessandra C. Pinheiro ◽  
...  

Abstract The crystal structures of four azines, namely 1-3-bis(4-methoxyphenyl)-2,3-diaza-1,4-butadiene, 1, 1,3-bis(2,3-dimethoxyphenyl)-2,3-diaza-1,4-butadiene, 2, 1,3-bis(2-hydroxy-3-methoxyphenyl)-2,3-diaza-1,4-butadiene, 3, and 1,3-bis(2-hydroxy-4-methoxyphenyl)-2,3-diaza-1,4-butadiene, 4, are reported. Molecules of 3 and 4, and both independent molecules of 2, Mol A and Mol B, possess inversion centers. The central C=N–N=C units in each molecule is planar with an (E,E) conformation. The intermolecular interactions found in the four compounds are C–H···O, C–H–N, C–H---π and π---π interactions. However, there is no consistent set of intermolecular interactions for the four compounds. Compound, 1, has a two-dimensional undulating sheet structure, generated from C–H···O and C–H···N intermolecular hydrogen bonds. The only recognized intermolecular interaction in 2 is a C–H···O hydrogen bond, which results in a zig-zag chain of alternating molecules, Mol A and Mol B. While 3 forms a puckered sheet of molecules, solely via C–H···π interactions, its isomeric compound, 4, has a more elaborate three-dimensional structure generated from a combination of C–H···O hydrogen bonds, C–H···π and π···π interactions. The findings in this study, based on both PLATON and Hirshfeld approaches, for the four representative compounds match well the reported structural findings in the literature of related compounds, which are based solely on geometric parameters.


2020 ◽  
Vol 56 (89) ◽  
pp. 13776-13779
Author(s):  
Jian Deng ◽  
Yuejuan Wan ◽  
Chang Cai ◽  
Cheng Gu ◽  
Yuguang Ma

Cyano-substituted oligo(p-phenylene vinylene) derivatives with π–π interactions and intermolecular hydrogen bonds in orthogonal directions were synthesised, and demonstrated very low defect density by OFETs.


2019 ◽  
Vol 48 (35) ◽  
pp. 13378-13387 ◽  
Author(s):  
Constance Lecourt ◽  
Warren Madanamoothoo ◽  
Vivian Ferreol ◽  
Nicolas Bélanger-Desmarais ◽  
Lhoussain Khrouz ◽  
...  

One-electron transfer from Mn(ii) ions to an imino nitroxide radical gives mononuclear Mn(iii) complexes of the reduced amino imine-oxide form for which crystal structures evidence hydrogen bonds networks acting as a stabilizing driving-force.


2005 ◽  
Vol 60 (2) ◽  
pp. 164-168 ◽  
Author(s):  
A. Elmali ◽  
Y. Elerman ◽  
G. Eren ◽  
F. Gümüş ◽  
I. Svoboda

2-(3’-Hydroxypropyl)benzimidazolium (Hhpb) hexa- and tetrachloroplatinate (C10H13N2O)2·[PtCl6] 1 and (C10H13N2O)2·[PtCl4] 2 were synthesized and their crystal structures determined. Compound 1 is monoclinic, space group P21/n, a = 8.800(1), b = 14.389(2), c = 10.264(2) Å, β = 98.540(10)°, V = 1285.3(3) Å3, Z = 2 and Dc = 1.959 g cm−3. Compound 2 is triclinic, space group P1̄, a=7.8480(10), b=9.0460(10), c=9.6980(10) Å ,α =65.420(10), β =68.810(10), γ = 76.770(1)°,V =581.26(4) Å3, Z =1 and Dc =1.969 g cm−3. In both compounds, the Pt atoms reside at a centre of inversion. Compounds 1 and 2 are comprised of 2-(3’-hydroxypropyl)benzimidazolium (Hhpb)+: (C10H12N2O)+ and [PtCl6]2− and [PtCl4]2− ions, respectively, linked by intermolecular hydrogen bonds N...Cl [range from 3.428(3) to 3.584(4) Å ], N···O [2.769(5) Å ] and O···Cl [3.338(4) and 3.321(3) Å ] for 1, and N···Cl [3.162(7) Å ], N···O [2.749(8) Å ] and O···Cl [3.289(6) Å ] for 2.


2020 ◽  
Vol 76 (4) ◽  
pp. 367-374
Author(s):  
Aleksandra Bocian ◽  
Adam Gorczyński ◽  
Dawid Marcinkowski ◽  
Grzegorz Dutkiewicz ◽  
Violetta Patroniak ◽  
...  

The intermolecular interactions in the structures of a series of Schiff base ligands have been thoroughly studied. These ligands can be obtained in different forms, namely, as the free base 2-[(2E)-2-(1H-imidazol-4-ylmethylidene)-1-methylhydrazinyl]pyridine, C10H11N5, 1, the hydrates 2-[(2E)-2-(1H-imidazol-2-ylmethylidene)-1-methylhydrazinyl]-1H-benzimidazole monohydrate, C12H12N6·H2O, 2, and 2-{(2E)-1-methyl-2-[(1-methyl-1H-imidazol-2-yl)methylidene]hydrazinyl}-1H-benzimidazole 1.25-hydrate, C13H14N6·1.25H2O, 3, the monocationic hydrate 5-{(1E)-[2-(1H-1,3-benzodiazol-2-yl)-2-methylhydrazinylidene]methyl}-1H-imidazol-3-ium trifluoromethanesulfonate monohydrate, C12H13N6 +·CF3O3S−·H2O, 5, and the dicationic 2-{(2E)-1-methyl-2-[(1H-imidazol-3-ium-2-yl)methylidene]hydrazinyl}pyridinium bis(trifluoromethanesulfonate), C10H13N5 2+·2CF3O3S−, 6. The connection between the forms and the preferred intermolecular interactions is described and further studied by means of the calculation of the interaction energies between the neutral and charged components of the crystal structures. These studies show that, in general, the most important contribution to the stabilization energy of the crystal is provided by π–π interactions, especially between charged ligands, while the details of the crystal architecture are influenced by directional interactions, especially relatively strong hydrogen bonds. In one of the structures, a very interesting example of the nontypical F...O interaction was found and its length, 2.859 (2) Å, is one of the shortest ever reported.


2016 ◽  
Vol 72 (12) ◽  
pp. 1771-1775
Author(s):  
Yohei Tabuchi ◽  
Kazuma Gotoh ◽  
Hiroyuki Ishida

The crystal structures of title hydrogen-bonded co-crystals, 2C12H16O3·C12H10N2, (I), and 2C13H18O3·C12H10N2, (II), have been determined at 93 K. In (I), the asymmetric unit consists of one 4-(n-pentyloxy)benzoic acid molecule and one half-molecule of (E)-1,2-bis(pyridin-4-yl)ethene, which lies about an inversion centre. The asymmetric unit of (II) comprises two crystallographically independent 4-(n-hexyloxy)benzoic acid molecules and one 1,2-bis(pyridin-4-yl)ethene molecule. In each crystal, the acid and base components are linked by O—H...N hydrogen bonds, forming a linear hydrogen-bonded 2:1 unit of the acid and the base. The 2:1 units are linkedviaC—H...π and π–π interactions [centroid–centroid distances of 3.661 (2) and 3.909 (2) Å for (I), and 3.546 (2)–3.725 (4) Å for (II)], forming column structures. In (II), the base molecule is orientationally disordered over two sets of sites approximately around the N...N molecular axis, with an occupancy ratio of 0.647 (4):0.353 (4), and the average structure of the 2:1 unit adopts nearly pseudo-C2symmetry. Both compounds show liquid-crystal behaviour.


2012 ◽  
Vol 68 (10) ◽  
pp. o408-o412 ◽  
Author(s):  
Ashokkumar Subashini ◽  
Kandasamy Ramamurthi ◽  
Helen Stoeckli-Evans

The 4-chloro- [C14H11ClN2O2, (I)], 4-bromo- [C14H10BrN2O2, (II)] and 4-diethylamino- [C18H21N3O2, (III)] derivatives of benzylidene-4-hydroxybenzohydrazide, all crystallize in the same space group (P21/c), (I) and (II) also being isomorphous. In all three compounds, the conformation about the C=N bond isE. The molecules of (I) and (II) are relatively planar, with dihedral angles between the two benzene rings of 5.75 (12) and 9.81 (17)°, respectively. In (III), however, the same angle is 77.27 (9)°. In the crystal structures of (I) and (II), two-dimensional slab-like networks extending in theaandcdirections are formedviaN—H...O and O—H...O hydrogen bonds. The molecules stack head-to-tailviaπ–π interactions involving the aromatic rings [centroid–centroid distance = 3.7622 (14) Å in (I) and 3.8021 (19) Å in (II)]. In (III), undulating two-dimensional networks extending in thebandcdirections are formedviaN—H...O and O—H...O hydrogen bonds. The molecules stack head-to-headviaπ–π interactions involving inversion-related benzene rings [centroid–centroid distances = 3.6977 (12) and 3.8368 (11) Å].


1985 ◽  
Vol 38 (3) ◽  
pp. 401 ◽  
Author(s):  
MJ O'Connell ◽  
CG Ramsay ◽  
PJ Steel

The colourless crystalline form of the benzoylpyrazolone (2) has molecules with the NH structure (2c) stabilized by intermolecular hydrogen bonds. At room temperature crystals are monoclinic: P21/c, a 13.508(5), b 9.124(4), c 11.451(3)Ǻ, β 90.80(3)°, Z4; the structure was refined to R 0.059, Rw 0.048. The acetoacetylpyrazolone (3) has the OH structure (3c) with two intramolecular hydrogen bonds. At 193 K crystals are triclinic: Pī , a 7.142(2), b 13.704(8), c 14.699(7)Ǻ, α 117.36(3), β 96.87(3), γ 93.73(3)°, Z 4; the structure was refined to R 0.049, Rw 0.054.


2018 ◽  
Vol 74 (3) ◽  
pp. 283-288
Author(s):  
Robert Nestler ◽  
Anke Schwarzer ◽  
Tobias Gruber

Three anisole building blocks featuring bis(hydroxymethyl) or bis(bromomethyl) pendants have been analyzed with regard to their molecular structures and packing behaviour. The compounds are ethyl 3,5-bis(hydroxymethyl)-4-methoxybenzoate, C12H16O5, (I), [5-bromo-3-(hydroxymethyl)-2-methoxyphenyl]methanol [or 4-bromo-2,6-bis(hydroxymethyl)anisole], C9H11BrO3, (II), and 5-bromo-1,3-bis(bromomethyl)-2-methoxybenzene [or 4-bromo-2,6-bis(bromomethyl)anisole], C9H9Br3O, (III). A typical supramolecular pattern involved C—H...π interactions generating molecular stacks, while π–π interactions were only observed in the absence of bromine, indicating a striking influence on the distances between adjacent aromatic moieties. When comparing bis(hydroxymethyl) compound (II) with bis(bromomethyl) compound (III), we found that the strong O—H...O hydrogen bonds in a zigzag arrangement in the first are replaced by C—H...Br interactions in the second without a change in the general packing.


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