Structure and hydrogen bonding in 2,4-dihydroxybenzoic acid at 90, 100, 110 and 150 K; a theoretical and single-crystal X-ray diffraction study

2007 ◽  
Vol 63 (2) ◽  
pp. 303-308 ◽  
Author(s):  
Andrew Parkin ◽  
Martin Adam ◽  
Richard I. Cooper ◽  
Derek S. Middlemiss ◽  
Chick C. Wilson
Keyword(s):  
Hydrogen Bonding ◽  
Solid State ◽  
Hydrogen Bonds ◽  
X Ray Diffraction ◽  
Dihydroxybenzoic Acid ◽  
X Ray ◽  
Hydrogen Bond System ◽  
Proton Disorder ◽  
Intramolecular Hydrogen ◽  
Carboxylic Acid Dimer

A new polymorph of 2,4-dihydroxybenzoic acid is reported. The structure was characterized by multiple-temperature X-ray diffraction and solid-state DFT computations. The material shows a geometric pattern of hydrogen bonding consistent with cooperativity between the intermolecular carboxylic acid dimer and intramolecular hydrogen bonds. The presence of proton disorder within this hydrogen-bond system, which would support such a cooperative model, was not fully ruled out by the initial X-ray studies. However, solid-state calculations on the three possible end-point tautomers indicate that the dominant crystallographically observed configuration is substantially lower in energy than the other tautomers (by at least 9 kJ mol−1), indicating that no disorder should be expected. It is therefore concluded that no disorder is observed either in the intra- or intermolecular hydrogen bonds of the title compound and that the cooperativity between the hydrogen bonds is not present within the temperature range studied.

Supramolecular architectures in two 1:1 cocrystals of 5-fluorouracil with 5-bromothiophene-2-carboxylic acid and thiophene-2-carboxylic acid

2017 ◽  
Vol 73 (6) ◽  
pp. 481-485 ◽  
Author(s):  
Marimuthu Mohana ◽  
Packianathan Thomas Muthiah ◽  
Colin D. McMillen
Keyword(s):  
Solid State ◽  
Carboxylic Acid ◽  
Hydrogen Bonds ◽  
Crystal Structures ◽  
X Ray Diffraction ◽  
Base Pairs ◽  
X Ray ◽  
Supramolecular Architectures ◽  
Acid Acid ◽  
Carboxylic Acid Dimer

In solid-state engineering, cocrystallization is a strategy actively pursued for pharmaceuticals. Two 1:1 cocrystals of 5-fluorouracil (5FU; systematic name: 5-fluoro-1,3-dihydropyrimidine-2,4-dione), namely 5-fluorouracil–5-bromothiophene-2-carboxylic acid (1/1), C5H3BrO2S·C4H3FN2O2, (I), and 5-fluorouracil–thiophene-2-carboxylic acid (1/1), C4H3FN2O2·C5H4O2S, (II), have been synthesized and characterized by single-crystal X-ray diffraction studies. In both cocrystals, carboxylic acid molecules are linked through an acid–acid R 2 2(8) homosynthon (O—H...O) to form a carboxylic acid dimer and 5FU molecules are connected through two types of base pairs [homosynthon, R 2 2(8) motif] via a pair of N—H...O hydrogen bonds. The crystal structures are further stabilized by C—H...O interactions in (II) and C—Br...O interactions in (I). In both crystal structures, π–π stacking and C—F...π interactions are also observed.

Hydrogen Bonding in Acid Li-, Ni-, Tetrabutylammonium, and Ammonium Salts of Benzene-1,2,4,5-tetracarboxylic Acid (Pyromellitic Acid)

1992 ◽  
Vol 47 (8) ◽  
pp. 1141-1153 ◽  
Author(s):  
Sven M. Jessen ◽  
Horst Küppers ◽  
Dean C. Luehrs
Keyword(s):  
Hydrogen Bonding ◽  
Hydrogen Bonds ◽  
Ammonium Salts ◽  
Tetracarboxylic Acid ◽  
X Ray Diffraction ◽  
Intermolecular Hydrogen Bonds ◽  
Pyromellitic Acid ◽  
X Ray ◽  
Carboxylic Groups ◽  
Intramolecular Hydrogen

Four acid salts of pyromellitic acid (benzene-1,2,4,5-tetracarboxylic acid) have been synthesized and studied by X-ray diffraction and IR spectroscopy. (1) Dilithium dihydrogen pyromellitate pentahydrate, Li2[C6H2(COO)4H2]· 5H2O; monoclinic, P21/m, a = 6.214(2), b = 19.647(7), c = 6.592(2)Å, β = 115.90(2)°, Ζ = 2, R = 0.068, Rw = 0.067. (2) Hexaaquanickel dihydrogen pyromellitate, [Ni(H2O)6][C6H2(COO)4H2]; monoclinic, P2/m, a = 6.528(1), b = 9.927(2), c = 6.472(1)Å, β = 115.57(1)°, Z = 1, R = 0.044, Rw = 0.039. (3) Tetrabutylammonium trihydrogen pyromellitate, [(C4H9)4N][C6H2(COO)4H3]; monoclinic, P21/c, a = 9.719(4), b = 18.823(8), c = 15.795(5)Å, β = 107.42(3)°, Z = 4, R = 0.059, Rw = 0.039. (4) Diammonium dihydrogen pyromellitate, [NH4]2[C6H2(COO)4H2]; monoclinic, P21/c, a = 4.7665(6), b = 11.681(3), c = 10.149(2)Å, ß = 102.19(2)°, Z = 2, R = 0.045, Rw = 0.039. Compounds 1, 2, and 3 show very short intramolecular hydrogen bonds between adjacent carboxylic groups (O ••• O distances 2.384(6), 2.386(5), 2.387(3)Å, respectively). Compound 4 forms intermolecular hydrogen bonds (O ··· O distance 2.642(2) A). The different hydrogen bonding modes are also evident in the IR spectra.

Intramolecular hydrogen bonding in N-salicylideneanilines. X-ray diffraction and solid-state NMR studies

1995 ◽  
Vol 91 (1) ◽  
pp. 77 ◽  
Author(s):  
Krzysztof Wozniak ◽  
Heyong He ◽  
Jacek Klinowski ◽  
William Jones ◽  
Teresa Dziembowska ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Solid State ◽  
Solid State Nmr ◽  
Intramolecular Hydrogen Bonding ◽  
X Ray Diffraction ◽  
Nmr Studies ◽  
X Ray ◽  
Intramolecular Hydrogen

scholarly journals A trigonal coordination of Au(I) phosphane complexes stabilized by O–H⋯X (X = Cl–, Br–, I–) interactions

2021 ◽  
Author(s):  
Petra Gründlinger ◽  
Cezarina Cela Mardare ◽  
Thorsten Wagner ◽  
Uwe Monkowius
Keyword(s):  
Hydrogen Bonding ◽  
Carboxylic Acid ◽  
Hydrogen Bonds ◽  
Intramolecular Hydrogen Bonding ◽  
Molecular Structures ◽  
X Ray Diffraction ◽  
X Ray ◽  
Standard Linear ◽  
Intramolecular Hydrogen ◽  
Linear Coordination

AbstractIn this work, we show that intramolecular hydrogen bonding can be used to stabilize tri-coordinated phosphane-gold(I) complexes. Two molecular structures of 2-(diphenylphosphino)benzoic acid (L) coordinated to a gold(I) atom were determined by single-crystal X-ray diffraction. The linear L–Au–Br shows a standard linear coordination and dimerizes via hydrogen bonds of the carboxylic acid. Upon addition of two additional phosphane ligands the complex [L3Au]X is formed which is stabilized by three intramolecular –C(O)O–H…X hydrogen bonds as proven by the X-ray structure of the respective chlorido-complex. X-ray powder diffractograms suggest the same structure also for X– = Br– and I–. Graphic abstract

scholarly journals Single crystal synchrotron X-ray diffraction for imaging hydrogen bond evolution

2014 ◽  
Vol 70 (a1) ◽  
pp. C559-C559
Author(s):  
Lucy Saunders ◽  
Harriott Nowell ◽  
Lynne Thomas ◽  
Paul Raithby ◽  
Chick Wilson
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Hydrogen Bonds ◽  
Single Crystal ◽  
Variable Temperature ◽  
X Ray Diffraction ◽  
X Ray ◽  
Hydrogen Atom Position ◽  
Proton Disorder ◽  
Atom Position

Hydrogen bonding is a valuable intermolecular interaction in "engineering" solid-state materials. This is because of the directionality and relative strength (1) of these bonds. Hydrogen bonds enable charge and energy transfer, via H-bond evolution, in a range of biological and chemical systems (2). Recent work has demonstrated that single crystal X-ray diffraction can be used to image the evolution of hydrogen bonds, including variable temperature proton migration and proton disorder processes. In particular, in a recent study of the temperature dependent proton disorder in hydrogen bonded 3,5-dinitrobenzoic acid (3,5-DNBA) dimers, the proton disorder deduced from data collected on an X-ray laboratory source is in agreement with that found from neutron data (3). This work focuses on variable temperature single crystal synchrotron X-ray diffraction, for the imaging of evolving hydrogen bonds. The development of appropriate methodology is important here, particularly as previous studies have involved laboratory X-ray sources only. Results will be presented from variable temperature data collections on I19, at the Diamond Light Source, and on beamline 11.3.1, at the Advanced Light Source (ALS), on systems such as 3,5-DNBA and co-crystals of benzimidazole, both exhibiting proton disorder across hydrogen bonding interactions. Synchrotron X-ray diffraction measurements have also been used to follow the change in the position of a proton within an intramolecular [N–H···N]+ hydrogen bond across a range of proton-sponge molecular complexes. Importantly, it has been possible to visualise the evolving hydrogen atom position in Fourier difference electron density maps generated from the synchrotron data. In particular, for the 35-DNBA study, the clearest picture of the evolving hydrogen atom position is observed in those generated from data collected at the ALS; even clearer than that observed in X-ray laboratory and neutron measurements on the same system.

Salts of purine alkaloids caffeine and theobromine with 2,6-dihydroxybenzoic acid as coformer: structural, theoretical, thermal and spectroscopic studies

2021 ◽  
Vol 77 (11) ◽  
Author(s):  
Mateusz Gołdyn ◽  
Anna Komasa ◽  
Mateusz Pawlaczyk ◽  
Aneta Lewandowska ◽  
Elżbieta Bartoszak-Adamska
Keyword(s):  
Hydrogen Bonds ◽  
Water Solubility ◽  
Theoretical Calculations ◽  
Spectroscopic Studies ◽  
X Ray Diffraction ◽  
Dihydroxybenzoic Acid ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Purine Alkaloids ◽  
Vis Spectroscopy

The study of various forms of pharmaceutical substances with specific physicochemical properties suitable for putting them on the market is one of the elements of research in the pharmaceutical industry. A large proportion of active pharmaceutical ingredients (APIs) occur in the salt form. The use of an acidic coformer with a given structure and a suitable pK a value towards purine alkaloids containing a basic imidazole N atom can lead to salt formation. In this work, 2,6-dihydroxybenzoic acid (26DHBA) was used for cocrystallization of theobromine (TBR) and caffeine (CAF). Two novel salts, namely, theobrominium 2,6-dihydroxybenzoate, C7H9N4O2 +·C7H5O4 − (I), and caffeinium 2,6-dihydroxybenzoate, C8H11N4O2 +·C7H5O4 − (II), were synthesized. Both salts were obtained independently by slow evaporation from solution, by neat grinding and also by microwave-assisted slurry cocrystallization. Powder X-ray diffraction measurements proved the formation of the new substances. Single-crystal X-ray diffraction studies confirmed proton transfer between the given alkaloid and 26DHBA, and the formation of N—H...O hydrogen bonds in both I and II. Unlike the caffeine cations in II, the theobromine cations in I are paired by noncovalent N—H...O=C interactions and a cyclic array is observed. As expected, the two hydroxy groups in the 26DHBA anion in both salts are involved in two intramolecular O—H...O hydrogen bonds. C—H...O and π–π interactions further stabilize the crystal structures of both compounds. Steady-state UV–Vis spectroscopy showed changes in the water solubility of xanthines after ionizable complex formation. The obtained salts I and II were also characterized by theoretical calculations, Fourier-transform IR spectroscopy (FT–IR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and elemental analysis.

Two new CdII MOFs of 1,4-bis(1H-benzimidazol-1-yl)butane and flexible dicarboxylate ligands: luminescence sensing towards Fe3+

2020 ◽  
Vol 76 (11) ◽  
pp. 1024-1033
Author(s):  
Fang-Hua Zhao ◽  
Shi-Yao Li ◽  
Wen-Yu Guo ◽  
Zi-Hao Zhao ◽  
Xiao-Wen Guo ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Solid State ◽  
Hydrogen Bonds ◽  
Layer Structure ◽  
Three Dimensional ◽  
Supramolecular Network ◽  
Two Dimensional ◽  
X Ray Diffraction ◽  
X Ray ◽  
Vis Spectroscopy

Two new CdII MOFs, namely, two-dimensional (2D) poly[[[μ2-1,4-bis(1H-benzimidazol-1-yl)butane](μ2-heptanedioato)cadmium(II)] tetrahydrate], {[Cd(C7H10O4)(C18H18N4)]·4H2O} n or {[Cd(Pim)(bbimb)]·4H2O} n (1), and 2D poly[diaqua[μ2-1,4-bis(1H-benzimidazol-1-yl)butane](μ4-decanedioato)(μ2-decanedioato)dicadmium(II)], [Cd2(C10H16O4)2(C18H18N4)(H2O)2] n or [Cd(Seb)(bbimb)0.5(H2O)] n (2), have been synthesized hydrothermally based on the 1,4-bis(1H-benzimidazol-1-yl)butane (bbimb) and pimelate (Pim2−, heptanedioate) or sebacate (Seb2−, decanedioate) ligands. Both MOFs were structurally characterized by single-crystal X-ray diffraction. In 1, the CdII centres are connected by bbimb and Pim2− ligands to generate a 2D sql layer structure with an octameric (H2O)8 water cluster. The 2D layers are further connected by O—H...O hydrogen bonds, resulting in a three-dimensional (3D) supramolecular structure. In 2, the CdII centres are coordinated by Seb2− ligands to form binuclear Cd2 units which are linked by bbimb and Seb2− ligands into a 2D hxl layer. The 2D layers are further connected by O—H...O hydrogen bonds, leading to an 8-connected 3D hex supramolecular network. IR and UV–Vis spectroscopy, thermogravimetric analysis and solid-state photoluminescence analysis were carried out on both MOFs. Luminescence sensing experiments reveal that both MOFs have good selective sensing towards Fe3+ in aqueous solution.

Notizen: Solid State Structure of N,N-Dibenzylhydroxylamine

1995 ◽  
Vol 50 (4) ◽  
pp. 699-701 ◽  
Author(s):  
Norbert W. Mitzel ◽  
Jürgen Riede ◽  
Klaus Angermaier ◽  
Hubert Schmidbaur
Keyword(s):  
Solid State ◽  
Hydrogen Bonds ◽  
Single Crystal ◽  
Unit Cell ◽  
Monoclinic Space Group ◽  
State Structure ◽  
X Ray Diffraction ◽  
Space Group ◽  
Solid State Structure ◽  
X Ray

The solid-state structure of N,N-dibenzylhydroxylamine (1) has been determined by single crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P 21/n with four formula units in the unit cell. N,N-dibenzylhydroxylamine dimerizes to give N2O2H2 sixmembered rings as a result of the formation of two hydrogen bonds O - H ··· N in the solid state.

Sign in / Sign up

Export Citation Format

Share Document