Trityl Group as an Crystal Engineering Tool for Construction of Inclusion Compounds and for Suppression of Amide NH···O═C Hydrogen Bonds

2017 ◽  
Vol 17 (5) ◽  
pp. 2560-2568 ◽  
Author(s):  
Wioletta Bendzińska-Berus ◽  
Beata Warżajtis ◽  
Jadwiga Gajewy ◽  
Marcin Kwit ◽  
Urszula Rychlewska
2014 ◽  
Vol 70 (a1) ◽  
pp. C964-C964
Author(s):  
Lucy Mapp ◽  
Mateusz Pitak ◽  
Simon Coles ◽  
Srinivasulu Aitipamula

The study of multi-component crystals, as well as the phenomenon of polymorphism, both have relevance to crystal engineering. Obtaining a specific polymorph is crucial as different polymorphs usually exhibit different physical and chemical properties and often the origin of this behaviour is unknown. This is especially important in the pharmaceutical industry. Herein, we present results of comparative studies of an analgesic drug, ethenzamide and its co-crystals with saccharin. The co-crystalisation of ethenzamide (2-ethoxybenzamide, EA) with saccharin (1,1-dioxo-,1,2-benzothiazol-3-one, SAC) with a 1:1 stoichiometric ratio resulted in two polymorphic forms of the co-crystal. Form I crystallises in the triclinic P-1 space group, whereas form II crystallises in monoclinic space group P21/n. Previous crystal structure analyses on forms I and II revealed that in both polymorphs the primary carboxy-amide-imide heterosynthon is the same, however the secondary level of interactions which extends the hydrogen bond network is different. Form I consists of extended linear tapes via N-H···O hydrogen bonds, whereas form II is composed of stacks of tetrameric motifs including N-H···O hydrogen bonds and C-H···O interactions. These two forms of EA-SAC can be classified as synthon polymorphs at a secondary level of hydrogen bonding [1]. In our approach an accurate, high resolution charge density distribution analysis has been carried out to obtain greater insight into the electronic structures of both types of the EA-SAC co-crystals and relate differences in electronic distribution with their polymorphic behaviour. To describe the nature and role of inter and intra-molecular interactions in a quantitative manner, the Hansen-Coppens formalism [2] and Bader's AIM theory [3] approach have been applied.


2014 ◽  
Vol 47 (8) ◽  
pp. 2514-2524 ◽  
Author(s):  
Arijit Mukherjee ◽  
Srinu Tothadi ◽  
Gautam R. Desiraju

2016 ◽  
Vol 72 (2) ◽  
pp. 112-118
Author(s):  
Mwaffak Rukiah ◽  
Mahmoud M. Al-Ktaifani ◽  
Mohammad K. Sabra

The design of new organic–inorganic hybrid ionic materials is of interest for various applications, particularly in the areas of crystal engineering, supramolecular chemistry and materials science. The monohalogenated intermediates 1-(2-chloroethyl)pyridinium chloride, C5H5NCH2CH2Cl+·Cl−, (I′), and 1-(2-bromoethyl)pyridinium bromide, C5H5NCH2CH2Br+·Br−, (II′), and the ionic disubstituted products 1,1′-(ethylene-1,2-diyl)dipyridinium dichloride dihydrate, C12H14N22+·2Cl−·2H2O, (I), and 1,1′-(ethylene-1,2-diyl)dipyridinium dibromide, C12H14N22+·2Br−, (II), have been isolated as powders from the reactions of pyridine with the appropriate 1,2-dihaloethanes. The monohalogenated intermediates (I′) and (II′) were characterized by multinuclear NMR spectroscopy, while (I) and (II) were structurally characterized using powder X-ray diffraction. Both (I) and (II) crystallize with half the empirical formula in the asymmetric unit in the triclinic space groupP\overline{1}. The organic 1,1′-(ethylene-1,2-diyl)dipyridinium dications, which display approximateC2hsymmetry in both structures, are situated on inversion centres. The components in (I) are linkedviaintermolecular O—H...Cl, C—H...Cl and C—H...O hydrogen bonds into a three-dimensional framework, while for (II), they are connectedviaweak intermolecular C—H...Br hydrogen bonds into one-dimensional chains in the [110] direction. The nucleophilic substitution reactions of 1,2-dichloroethane and 1,2-dibromoethane with pyridine have been investigated byab initioquantum chemical calculations using the 6–31G** basis. In both cases, the reactions occur in two exothermic stages involving consecutive SN2 nucleophilic substitutions. The isolation of the monosubstituted intermediate in each case is strong evidence that the second step is not fast relative to the first.


2006 ◽  
Vol 128 (32) ◽  
pp. 10372-10373 ◽  
Author(s):  
Olivier Lebel ◽  
Thierry Maris ◽  
Marie-Ève Perron ◽  
Eric Demers ◽  
James D. Wuest

2018 ◽  
Vol 74 (8) ◽  
pp. 1111-1116 ◽  
Author(s):  
Shet M. Prakash ◽  
S. Naveen ◽  
N. K. Lokanath ◽  
P. A. Suchetan ◽  
Ismail Warad

2-Aminopyridine and citric acid mixed in 1:1 and 3:1 ratios in ethanol yielded crystals of two 2-aminopyridinium citrate salts, viz. C5H7N2 +·C6H7O7 − (I) (systematic name: 2-aminopyridin-1-ium 3-carboxy-2-carboxymethyl-2-hydroxypropanoate), and 3C5H7N2 +·C6H5O7 3− (II) [systematic name: tris(2-aminopyridin-1-ium) 2-hydroxypropane-1,2,3-tricarboxylate]. The supramolecular synthons present are analysed and their effect upon the crystal packing is presented in the context of crystal engineering. Salt I is formed by the protonation of the pyridine N atom and deprotonation of the central carboxylic group of citric acid, while in II all three carboxylic groups of the acid are deprotonated and the charges are compensated for by three 2-aminopyridinium cations. In both structures, a complex supramolecular three-dimensional architecture is formed. In I, the supramolecular aggregation results from Namino—H...Oacid, Oacid...H—Oacid, Oalcohol—H...Oacid, Namino—H...Oalcohol, Npy—H...Oalcohol and Car—H...Oacid interactions. The molecular conformation of the citrate ion (CA3−) in II is stabilized by an intramolecular Oalcohol—H...Oacid hydrogen bond that encloses an S(6) ring motif. The complex three-dimensional structure of II features Namino—H...Oacid, Npy—H...Oacid and several Car—H...Oacid hydrogen bonds. In the crystal of I, the common charge-assisted 2-aminopyridinium–carboxylate heterosynthon exhibited in many 2-aminopyridinium carboxylates is not observed, instead chains of N—H...O hydrogen bonds and hetero O—H...O dimers are formed. In the crystal of II, the 2-aminopyridinium–carboxylate heterosynthon is sustained, while hetero O—H...O dimers are not observed. The crystal structures of both salts display a variety of hydrogen bonds as almost all of the hydrogen-bond donors and acceptors present are involved in hydrogen bonding.


1997 ◽  
Vol 53 (3) ◽  
pp. 513-520 ◽  
Author(s):  
G. Ferguson ◽  
P. I. Coupar ◽  
C. Glidewell

4,4′-Isopropylidenediphenol-1,4-diazabicyclo[2.2.2]octane (1/1), (1), C15H16O2.C6H12N2, monoclinic, P2/a, a = 11.385 (2), b = 6.5565 (12), c = 13.076 (2) Å, \beta = 96.240 (11)°, with Z = 2; the two components of the adduct, which each lie across twofold axes, are joined into simple chains via O—H...N hydrogen bonds in a motif with graph set C_{2}^2(17). 4,4′-Oxodiphenol-1,4-diazabicyclo[2.2.2]octane (1/1), (2), C12H10O3.C6H12N2, orthorhombic, P212121, a = 9.4222 (11), b = 11.1886 (15), c = 15.694 (2), with Z = 4; the diamine component is disordered by rotation about the N...N vector, having two orientations [populations 0.76 (1) and 0.24 (1)] rotated by 48 (3)° from coincidence: the components are joined into chains via O—H...N hydrogen bonds in a motif with graph set C_{2}^2(17); pairs of these chains are joined into ladders by C—H...O hydrogen bonds in a motif of graph set R_{2}^2(22). 4,4′-Thiodiphenol-l,4-diazabicyclo[2.2.2]octane (1/1), (3), C12H10O2S.C6H12N2, isomorphous, a = 9.5785 (11), b = 11.4525 (13), c = 15.759 (2) Å (and ipso facto isostructural), with (2); the diamine disorder is characterized by two equally populated orientations related by a rotation about the N...N vector of 37.1 (2)° and pairs of chains are now joined into ladders by C—H...S hydrogen bonds. 4,4′-Thiodiphenol-1,4-diazabicyclo[2.2.2]octane (2/1), (5), (C12H10O2S)2.C6H12N2, monoclinic, P21/n, a = 8.3198 (9), b = 11.4006 (13), c = 15.056 (2) Å, \beta = 104.955 (8)°, with Z = 2; the diamine component of the adduct is disordered across a centre of inversion, and the bisphenol components are linked into chains by O—H...O hydrogen bonds in a motif with graph set C(12). These chains form cross-links via the diamine component by means of O—H...N hydrogen bonds in a C_{3}^3(19) motif to yield sheets within which are large hydrogen-bonded rings described by the unusual graph set R_{8}^8(62).


Author(s):  
Maciej Bujak

The ability to intentionally construct, through different types of interactions, inorganic–organic hybrid materials with desired properties is the main goal of inorganic crystal engineering. The primary deformation, related to intrinsic interactions within inorganic substructure, and the secondary deformation, mainly caused by the hydrogen bond interactions, are both responsible for polyhedral distortions of halogenidoantimonates(III) with organic cations. The evolution of structural parameters, in particular the Sb—I secondary- and O/N/C—H...I hydrogen bonds, as a function of temperature assists in understanding the contribution of those two distortion factors to the irregularity of [SbI6]3−polyhedra. In tris(piperazine-1,4-diium) bis[hexaiodidoantimonate(III)] pentahydrate, (C4H12N2)3[SbI6]2·5H2O (TPBHP), where the isolated [SbI6]3–units were found, distortion is governed only by O/N/C—H...I hydrogen bonds, whereas in piperazine-1,4-diium bis[tetraiodidoantimonate(III)] tetrahydrate, (C4H12N2)[SbI4]2·4H2O (PBTT), both primary and O—H...I secondary factors cause the deformation of one-dimensional [{SbI4}n]n−chains. The larger in spatial dimensions piperazine-1,4-diium cations, in contrast to the smaller water of crystallization molecules, do not significantly contribute to the octahedral distortion, especially in PBTT. The formation of isolated [SbI6]3−ions in TPBHP is the result of specific second coordination sphere hydrogen bond interactions that stabilize the hybrid structure and simultaneously effectively separate and prevent [SbI6]3−units from mutual interactions. The temperature-induced changes, further supported by the analysis of data retrieved from the Cambridge Structural Database, illustrate the significance of both primary and secondary distortion factors on the deformation of octahedra. Also, a comparison of packing features in the studied hybrids with those in the non-metal containing piperazine-1,4-diium diiodide diiodine (C4H12N2)I2·I2(PDD) confirms the importance and hierarchy of different types of interactions.


2014 ◽  
Vol 70 (a1) ◽  
pp. C988-C988
Author(s):  
Sergey Arkhipov ◽  
Boris Zakharov ◽  
Elena Boldyreva

"Experiments for studying crystalline materials under extreme conditions are a powerful tool for investigating ""structure-property"" relationships. They also give information on the behavior of hydrogen bonds and are important both for materials science and crystal engineering. In addition, many processes in the living organisms are also related to mechanical stress. One of the most interesting tasks is to identify factors which influence the stability of a structure, or a part of the structure, at high pressure. Experiments on the systematic study of compounds in a wide range of pressures allow us to accumulate data that can be used to solve this problem. For a more complete picture, the mixed crystals of the selected compound are studied. Investigation of mixed crystals and cocrystals of interest can be compared with the crystals of individual compounds. We have chosen the structure of L-serine - L-ascorbic acid to be compared with those of L-serine and L-ascorbic acids for such a study. Phase transitions were previously reported to be induced by increasing pressure in both L-serine [1] and L-ascorbic acid [2]; moreover, the structure of L-serine was followed at multiple pressures by single-crystal and powder X-ray diffraction[3]. L-serine – L-ascorbic acid co-crystal was studied in the pressure range 0-5.4 GPa (at multiple points at every 0.5-0.7 GPa) by single-crystal X-ray diffraction and Raman spectroscopy. A phase transition has been detected and some rearrangement in the network of hydrogen bonds was observed. The high pressure data were compared with those for the individual structures of the L-serine and L-ascorbic acid. This work was supported by RFBR (grants 12–03-31541, 14-03-31866, 13-03-92704, 14-03-00902 ), Ministry of Science and Education of Russia and Russian Academy of Sciences."


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