Different acid–base behaviour of a pyrazole and an isoxazole with organic acids: crystal and molecular structures of the salt 3-(4-fluorophenyl)-1H-pyrazolium 2,4,6-trinitrophenolate and of the cocrystal 4-amino-N-(3,4-dimethyl-1,2-oxazol-5-yl)benzenesulfonamide–3,5-dinitrobenzoic acid (1/1)

2016 ◽  
Vol 72 (8) ◽  
pp. 612-618
Author(s):  
Marisiddaiah Girisha ◽  
Hemmige S. Yathirajan ◽  
Jerry P. Jasinski ◽  
Christopher Glidewell

Pyrazole and isoxazole rings differ only in the notional replacement of a potential hydrogen-bond-donor NH unit in pyrazole by a potential hydrogen-bond-acceptor O atom in isoxazole. It is thus of interest to compare the hydrogen-bonding characteristics of these rings. (4-Fluorophenyl)pyrazole undergoes protonation in the presence of 2,4,6-trinitrophenol to yield the salt 3-(4-fluorophenyl)-1H-pyrazolium 2,4,6-trinitrophenolate, C9H8FN2+·C6H2N3O7−, (I), whereas there is no proton transfer between 4-amino-N-(3,4-dimethyl-1,2-oxazol-5-yl)benzenesulfonamide and 3,5-dinitrobenzoic acid, whose reaction gives the 1:1 cocrystal, C11H13N3O3S·C7H4N2O6, (II). The bond lengths in salt (I) provide evidence for aromatic-type delocalization in the pyrazolium ring and for extensive delocalization of the negative charge into the ring of the trinitrophenolate anion. The O atoms of one of the nitro groups in the trinitrophenolate anion are disordered over two sets of atomic sites having occupancies of 0.571 (6) and 0.429 (6), but all of the other substituents on the carbocyclic rings are fully ordered. The ions in salt (I) are linked by an extensive series of N—H...O hydrogen bonds to form a three-dimensional framework structure, and in cocrystal (II), the molecular components are linked by a combination of O—H...N and N—H...O hydrogen bonds to form complex bilayers. Comparisons are made with some related compounds.

2006 ◽  
Vol 62 (5) ◽  
pp. o1754-o1755
Author(s):  
Neng-Fang She ◽  
Sheng-Li Hu ◽  
Hui-Zhen Guo ◽  
An-Xin Wu

The title compound, C24H18Br2N4O2·H2O, forms a supramolecular structure via N—H...O, O—H...O and C—H...O hydrogen bonds. In the crystal structure, the water molecule serves as a bifurcated hydrogen-bond acceptor and as a hydrogen-bond donor.


2014 ◽  
Vol 70 (11) ◽  
pp. 1011-1016 ◽  
Author(s):  
Prakash S. Nayak ◽  
Badiadka Narayana ◽  
Hemmige S. Yathirajan ◽  
Eric C. Hosten ◽  
Richard Betz ◽  
...  

The structures of a chalcone and of its cyclocondensation product with guanidine are reported. In (2E)-3-(6-methoxynaphthalen-2-yl)-1-(pyridin-3-yl)prop-2-en-1-one, C19H15NO2, (I), the planes of the pyridine and naphthalene units make dihedral angles with that of the central spacer unit of 23.61 (13) and 23.57 (15)°, respectively, and a dihedral angle of 47.24 (9)° with each other. The molecules of (I) are linked into sheets by a combination of C—H...O and C—H...π(arene) hydrogen bonds. In the cyclocondensation product (4RS)-2-amino-4-(6-methoxynaphthalen-2-yl)-6-(pyridin-3-yl)-3,4-dihydropyrimidine monohydrate, C20H18N4O·H2O, (II), the dihydropyrimidine ring adopts a conformation best described as a shallow boat. The molecular components are linked by two N—H...O hydrogen bonds, two O—H...N hydrogen bonds and one N—H...N hydrogen bond to form complex sheets, with the methoxynaphthalene interdigitated between inversion-related pairs of sheets.


2012 ◽  
Vol 68 (11) ◽  
pp. o439-o442 ◽  
Author(s):  
Jairo Quiroga ◽  
Jaime Gálvez ◽  
Justo Cobo ◽  
Christopher Glidewell

The racemic title dipyrrolopyrrolizine compound crystallizes from dimethylformamide as a disolvate, C55H39Cl2N7O6·2C3H7NO. None of the four fused heterocyclic rings is planar; one adopts an envelope conformation, two others adopt half-chair conformations and the fourth adopts a conformation intermediate between an envelope and a half-chair. The arrangement of the ring fusions is such as to preclude the possibility of internal mirror symmetry. The three independent molecular components are weakly linked by C—H...O hydrogen bonds, and the dipyrrolopyrrolizine molecules are linked by a combination of four C—H...O and one C—H...π(arene) hydrogen bond to form a three-dimensional framework, from which the dimethylformamide solvent molecules are pendent. However, aromatic π–π stacking interactions are absent in the structure.


2015 ◽  
Vol 71 (9) ◽  
pp. 824-833 ◽  
Author(s):  
Amir Hossein Alamdar ◽  
Mehrdad Pourayoubi ◽  
Anahid Saneei ◽  
Michal Dušek ◽  
Monika Kučeráková ◽  
...  

Hirshfeld surfaces and two-dimensional fingerprint plots are used to analyse the intermolecular interactions in two new phosphorothioic triamide structures, namelyN,N′,N′′-tris(3,4-dimethylphenyl)phosphorothioic triamide acetonitrile hemisolvate, P(S)[NHC6H3-3,4-(CH3)2]3·0.5CH3CN or C24H30N3PS·0.5CH3CN, (I), andN,N′,N′′-tris(4-methylphenyl)phosphorothioic triamide–3-methylpiperidinium chloride (1/1), P(S)[NHC6H4(4-CH3)]3·[3-CH3-C5H9NH2]+·Cl−or C21H24N3PS·C6H14N+·Cl−, (II). The asymmetric unit of (I) consists of two independent phosphorothioic triamide molecules and one acetonitrile solvent molecule, whereas for (II), the asymmetric unit is composed of three components (molecule, cation and anion). In the structure of (I), the different components are organized into a six-molecule aggregate through N—H...S and N—H...N hydrogen bonds. The components of (II) are aggregated into a two-dimensional array through N—H...S and N—H...Cl hydrogen bonds. Moreover, interesting features of packing arise in this structure due to the presence of a double hydrogen-bond acceptor (the S atom of the phosphorothioic triamide molecule) and of a double hydrogen-bond donor (the N—H unit of the cation). For both (I) and (II), the full fingerprint plot of each component is asymmetric as a consequence of the presence of three fragments. These analyses reveal that H...H interactions [67.7 and 64.3% for the two symmetry-independent phosphorothioic triamide molecules of (I), 30.7% for the acetonitrile solvent of (I), 63.8% in the phosphorothioic triamide molecule of (II) and 62.9% in the 3-methylpiperidinium cation of (II)] outnumber the other contacts for all the components in both structures, except for the chloride anion of (II), which only receives the Cl...H contact. The phosphorothioic triamide molecules of both structures include unsaturated C atoms, thus presenting C...H/H...C interactions: 17.6 and 21% for the two symmetry-independent phosphorothioic triamide molecules in (I), and 22.7% for the phosphorothioic triamide molecule of (II). Furthermore, the N—H...S hydrogen bonds in both (I) and (II), and the N—H...Cl hydrogen bonds in (II), are the most prominent interactions, appearing as large red spots on the Hirshfeld surface maps. The N...H/H...N contacts in structure (I) are considerable, whereas for (II), they give a negligible contribution to the total interactions in the system.


1998 ◽  
Vol 54 (2) ◽  
pp. 139-150 ◽  
Author(s):  
G. Ferguson ◽  
C. Glidewell ◽  
R. M. Gregson ◽  
P. R. Meehan

The structure of 4,4′-thiodiphenol–1,4,8,11-tetraazacyclotetradecane (2/1), (C12H10O2S)2.C10H24N4 (1), monoclinic, P21/c, a = 11.1602 (12), b = 10.8084 (12), c = 14.001 (2) Å, β = 103.127 (10)°, with Z = 2, contains phenolate anions [HOC6H4SC6H4O]− and diprotonated cyclam cations [C10H26N4]2+: these cations have the centrosymmetric trans-III conformation and the two additional protons are contained within the N4 cavity of the macrocycle, held by three-centre hydrogen bonds. The phenolate anions form chains, held together by O—H...O hydrogen bonds, and pairs of these chains are cross-linked into ladders by the [cyclamH2]2+ cations by means of N—H...O hydrogen bonds. The structure of 4,4′-sulfonyldiphenol–1,4,8,11-tetraazacyclotetradecane (2/1), (C12H10O4S)2.C10H24N4 (2), triclinic, P1¯, a = 10.9345 (10), b = 11.0060 (10), c = 14.350 (2) Å, α = 79.532 (10), β = 86.739 (10), γ = 87.471 (10)°, with Z = 2, contains phenolate anions [HOC6H4SO2C6H4O]− and cyclam dications [C10H26N4]2+: the phenolate anions are linked into antiparallel chains, cross-linked by the cyclam cations. There are two distinct types of ladder in the structure running along (0, y, 0) and (1\over2, y, 1\over2), respectively, and these bundled ladders are tied together by C—H...O hydrogen bonds to form a continuous three-dimensional array. In 1,1,1-tris(4-hydroxyphenyl)ethane–1,4,8,11-tetraazacyclotetradecane–methanol (2/1/1), (C20H18O3)2.C10H24N4.CH4O (3), triclinic, P1¯, a = 8.2208 (11), b = 16.245 (2), c = 17.337 (2) Å, α = 81.694 (13), β = 89.656 (14), γ = 86.468 (12)°, with Z = 2, the structure contains centrosymmetric diprotonated cyclam cations of precisely the same type as found in (1), phenolate anions [(HOC6H4)2C(CH3)C6H4O]− and neutral methanol molecules. The molecular components are linked together by nine different types of hydrogen bond, five of O—H...O type and four of N—H...O type, to form chains running in the [001], [010] (two sets), [211] and [211¯] directions. The combination of these chain motifs generates two independent three-dimensional networks which are fully interwoven, but not bonded to one another.


2018 ◽  
Vol 74 (12) ◽  
pp. 1783-1789
Author(s):  
Asma ◽  
Balakrishna Kalluraya ◽  
Hemmige S. Yathirajan ◽  
Ravindranath S. Rathore ◽  
Christopher Glidewell

Four 1-aryl-1H-pyrazole-3,4-dicarboxylate derivatives, one acid, two esters and a dicarbohydrazide have been synthesized starting from 3-aryl sydnones, and structurally characterized. There is an intramolecular O—H...O hydrogen bond in 1-phenyl-1H-pyrazole-3,4-dicarboxylic acid, C11H8N2O4, (I), and the molecules are linked into a three-dimensional framework structure by a combination of O—H...O, O—H...N, C—H...O and C—H...π(arene) hydrogen bonds. In each of the two esters dimethyl 1-phenyl-1H-pyrazole-3,4-dicarboxylate, C13H12N2O4, (II), and dimethyl 1-(4-methylphenyl)-1H-pyrazole-3,4-dicarboxylate, C14H14N2O4, (III), C—H...O hydrogen bonds lead to the formation of cyclic centrosymmetric dimers: in (III), one of the methoxycarbonyl groups is disordered over two sets of atomic sites having occupancies 0.71 (2) and 0.29 (2). An intramolecular N—H...O hydrogen bond is present in the structure of 1-(4-methoxyphenyl)-1H-pyrazole-3,4-dicarbohydrazide, C12H14N6O3, (IV), and the molecules are linked into a three-dimensional framework structure by a combination of N—H...O, N—H...N, N—H...π(arene) and C—H...O hydrogen bonds. Comparisons are made with the structures of a number of related compounds.


Author(s):  
Mhamed Boudraa ◽  
Sofiane Bouacida ◽  
Hasna Bouchareb ◽  
Hocine Merazig ◽  
El Hossain Chtoun

In the title compound, [CoCl2(H2O)4]·2C4H8SO2, the CoIIcation is located on the twofold rotation axis and is coordinated by four water molecules and two adjacent chloride ligands in a slightly distorted octahedral coordination environment. Thecisoidangles are in the range 83.27 (5)–99.66 (2)°. The threetransoidangles deviate significantly from the ideal linear angle. The crystal packing can be described as a linear arrangement of complex units alongcformed by bifurcated O—H...Cl hydrogen bonds between two water molecules from one complex unit towards one chloride ligand of the neighbouring complex. Two solvent molecules per complex are attached to this infinite chainviaO—H...O hydrogen bonds in which water molecules act as the hydrogen-bond donor and sulfolane O atoms as the hydrogen-bond acceptor sites.


1983 ◽  
Vol 36 (4) ◽  
pp. 701 ◽  
Author(s):  
T Yokoyama ◽  
RW Taft ◽  
MJ Kamlet

The N-H protons of N-methyl-2-X-aniline derivatives remain intramolecularly hydrogen bonded in HBA (hydrogen bond acceptor) solvents where X = COOMe and NO2, but form intermolecular hydrogen bonds to the HBA solvents where X = CN. The order of response of vmax to solvent HBA basicity for the Cl → C2 bands of N-unsubstituted-2-(-M)-substituted aniline derivatives and the Cl → C4 bands of 4-(-M)-substituted aniline derivatives follows the orders of the hydrogen bond donor acidities of the amine protons, which are determined primarily by the mesomeric effects of the 2- and 4-substituents. The spectral data indicate that intramolecularly hydrogen bonded 2-(-M)-substituted aniline derivatives are near sp2 hybridized in non-HBA solvents and, unlike several 4-substitute anilines, do not undergo significant rehybridization in HBA solvents. Bath ochromic shifts resulting from hydrogen bonds by corresponding 2- and 4-substituted aniline derivatives to HBA solvents are of similar magnitudes.


2019 ◽  
Vol 75 (8) ◽  
pp. 1253-1260 ◽  
Author(s):  
Haruvegowda Kiran Kumar ◽  
Hemmige S. Yathirajan ◽  
Belakavadi K. Sagar ◽  
Sabine Foro ◽  
Christopher Glidewell

Six new 1-aroyl-4-(4-methoxyphenyl)piperazines have been prepared, using coupling reactions between benzoic acids and N-(4-methoxyphenyl)piperazine. There are no significant hydrogen bonds in the structure of 1-benzoyl-4-(4-methoxyphenyl)piperazine, C18H20N2O2, (I). The molecules of 1-(2-fluorobenzoyl)-4-(4-methoxyphenyl)piperazine, C18H19FN2O2, (II), are linked by two C—H...O hydrogen bonds to form chains of rings, which are linked into sheets by an aromatic π–π stacking interaction. 1-(2-Chlorobenzoyl)-4-(4-methoxyphenyl)piperazine, C18H19ClN2O2, (III), 1-(2-bromobenzoyl)-4-(4-methoxyphenyl)piperazine, C18H19BrN2O2, (IV), and 1-(2-iodobenzoyl)-4-(4-methoxyphenyl)piperazine, C18H19IN2O2, (V), are isomorphous, but in (III) the aroyl ring is disordered over two sets of atomic sites having occupancies of 0.942 (2) and 0.058 (2). In each of (III)–(V), a combination of two C—H...π(arene) hydrogen bonds links the molecules into sheets. A single O—H...O hydrogen bond links the molecules of 1-(2-hydroxybenzoyl)-4-(4-methoxyphenyl)piperazine, C18H20N2O3, (VI), into simple chains. Comparisons are made with the structures of some related compounds.


2020 ◽  
Vol 76 (10) ◽  
pp. 1629-1633
Author(s):  
Mohammed A. E. Shaibah ◽  
Channappa N. Kavitha ◽  
Hemmige S. Yathirajan ◽  
Sabine Foro ◽  
Christopher Glidewell

In the title salt {systematic name: 4-[6-chloro-2,9-diazatricyclo[9.4.0.03,8]pentadeca-1(15),3(8),4,6,9,11,13-heptaen-10-yl]-1-methylpiperazin-1-ium 3,5-dinitrobenzoate–3,5-dinitrobenzic acid (1/1)}, C18H20ClN4 +·C7H3N2O6 −·C7H4N2O6, there is a very short, asymmetric, O—H...O hydrogen bond [O...O = 2.453 (3) Å] within the anion. The oxygen atoms of one of the nitro groups of the anion are disordered over two sets of sites having occupancies of 0.56 (3) and 0.44 (3). The fused tricyclic portion of the cation adopts a butterfly conformation, with a dihedral angle of 45.59 (6)° between the planes of the two aryl rings. In the crystal, a combination of O—H...O, N—H...O and C—H...O hydrogen bonds links the component species into a three-dimensional framework. Comparisons are made with the structures of some related compounds.


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