共查询到20条相似文献,搜索用时 15 毫秒
1.
Christopher Glidewell John N. Low Janet M. S. Skakle James L. Wardell 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(4):o201-o203
Molecules of the title compound, [(4‐nitrophenyl)sulfanyl]acetic acid, C8H7NO4S, are linked by paired O—H?O hydrogen bonds [H?O 1.81 Å, O?O 2.6456 (15) Å and O—H?O 178°] into centrosymmetric dimers containing an R(8) motif. A single C—H?O hydrogen bond having a nitro O atom as acceptor [H?O 2.47 Å, 3.3018 (19) Å and C—H?O 147°] links the dimers into a molecular ladder, and neighbouring ladders are weakly linked into sheets by aromatic π–π‐stacking interactions. 相似文献
2.
Jing Zhang Xueliang Hou Weifeng Bu Lixin Wu Ling Ye Guangdi Yang Yuguo Fan 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(11):o663-o664
The title compound (systematic name: 4,4′‐ethylenedipyridinium dimaleate), C12H12N22+·2C4H3O4?, is a 1:2 adduct of 1,2‐bis(4‐pyridyl)ethylene (BPE) and maleic acid (MA). The interaction between the two components in the molecular complex is due to intermolecular hydrogen bonding via an N+—H?O? hydrogen bond. 相似文献
3.
Philip J. Cox James L. Wardell 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(8):o515-o517
The molecular structure of the title compound, C20H24B2N2O2S, is characterized by a twofold rotation axis passing through the S atom and the midpoint of the C—C single bond in the thiophene ring. A coordinative NB bond is present in the boroxazolidine ring and a single N—H?O hydrogen bond [H?O 1.93 (3) Å, N?O 2.829 (3) Å and N—H?O 172 (2)°] links the molecules into a molecular ladder. 相似文献
4.
Vladimir O. Gelmboldt Eduard V. Ganin Konstantin V. Domasevitch 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(9):o530-o534
In bis(2‐carboxypyridinium) hexafluorosilicate, 2C6H6NO2+·SiF62−, (I), and bis(2‐carboxyquinolinium) hexafluorosilicate dihydrate, 2C10H8NO2+·SiF62−·2H2O, (II), the Si atoms of the anions reside on crystallographic centres of inversion. Primary inter‐ion interactions in (I) occur via strong N—H...F and O—H...F hydrogen bonds, generating corrugated layers incorporating [SiF6]2− anions as four‐connected net nodes and organic cations as simple links in between. In (II), a set of strong N—H...F, O—H...O and O—H...F hydrogen bonds, involving water molecules, gives a three‐dimensional heterocoordinated rutile‐like framework that integrates [SiF6]2− anions as six‐connected and water molecules as three‐connected nodes. The carboxyl groups of the cation are hydrogen bonded to the water molecule [O...O = 2.5533 (13) Å], while the N—H group supports direct bonding to the anion [N...F = 2.7061 (12) Å]. 相似文献
5.
Anders Lennartson Mikael Hkansson 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(3):m69-m74
Four complexes containing the [UO2(oda)2]2− anion (oda is oxydiacetate) are reported, namely dipyridinium dioxidobis(oxydiacetato)uranate(VI), (C5H6N)2[U(C4H4O5)2O2], (I), bis(2‐methylpyridinium) dioxidobis(oxydiacetato)uranate(VI), (C8H8N)2[U(C4H4O5)2O2], (II), bis(3‐methylpyridinium) dioxidobis(oxydiacetato)uranate(VI), (C8H8N)2[U(C4H4O5)2O2], (III), and bis(4‐methylpyridinium) dioxidobis(oxydiacetato)uranate(VI), (C8H8N)2[U(C4H4O5)2O2], (IV). The anions are achiral and are located on a mirror plane in (I) and on inversion centres in (II)–(IV). The four complexes are assembled into three‐dimensional structures via N—H...O and C—H...O interactions. Compounds (III) and (IV) are isomorphous; the [UO2(oda)2]2− anions form a porous matrix which is nearly identical in the two structures, and the cations are located in channels formed in this matrix. Compounds (I) and (II) are very different from (III) and (IV): (I) forms a layered structure, while (II) forms ribbons. 相似文献
6.
Solange M. S. V. Wardell James L. Wardell Mark F. Ward John N. Low Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(7):865-867
Crystals of the title compound, C18H20N4O4, contain equal numbers of (R,R) and (S,S) molecules, but these are not precise enantiomorphs, neither are they related by crystallographic symmetry; in addition, each molecule exhibits approximate, but not exact, twofold rotational symmetry. There are intramolecular N—H?O hydrogen bonds [N?O 2.609 (4)–2.638 (5) Å; N—H?O 125–132°] and the molecules are linked into molecular ladders by C—H?O hydrogen bonds [C?O 3.306 (6)–3.386 (6) Å; C—H?O 146–160°]. 相似文献
7.
Chin‐Ping Yang Ruei‐Shin Chen 《Journal of polymer science. Part A, Polymer chemistry》2002,40(4):429-438
A diamine monomer II , 2,5‐bis(4‐aminophenoxy)biphenyl, was prepared through a nucleophilic substitution reaction of phenylhydroquinone and p‐chloronitrobenzene in the presence of potassium carbonate in N,N‐dimethylformamide, followed by catalytic reduction with hydrazine and Pd/C. A series of all‐aromatic, organosoluble polyimides bearing pendent phenyl groups were synthesized from the diamine with six kinds of commercial dianhydrides via a conventional two‐stage process. For improving solubility of polypyromellitimide, copolypyromellitimides with arbitrary solubilities were prepared from II and a pair of dianhydrides, which were mixed at certain molar ratios. These polymers showed good solubilities in N‐methyl‐2‐pyrrolidone and m‐cresol. The softening temperatures of these polyimides were recorded between 206 and 269 °C. Polymers had glass‐transition temperatures at 230–286 °C and 10% weight‐loss temperatures above 521 °C in air or nitrogen atmospheres. Their films had high tensile moduli and strengths. Excellent properties of these polyimides are attributed to the incorporation of the pendent phenyl group in diamine II . © 2002 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 429–438, 2002; DOI 10.1002/pola.10116 相似文献
8.
C. Foces‐Foces M. Lpez‐Rodríguez 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(12):o657-o660
2,6‐Bis(tert‐butyldimethylsilyloxy)‐9‐oxabicyclo[3.3.1]nonane‐3,7‐diol, C20H42O5Si2, (I), and 4,8‐bis(tert‐butyldimethylsilyloxy)‐2,6‐dioxatricyclo[3.3.13,7]decane‐1,3‐diol, C20H40O6Si2, (II), form layered structures that differ in the way the molecules are connected within each layer. The endocyclic O atom common to both structures plays an active role in the hydrogen‐bonding network, whereas the second oxygen bridge in (II) does not participate in any interaction. This work reports the first structural analysis of two bis(tert‐butyldimethylsilyloxy)‐substituted cyclic diol derivatives and provides insight into the influence of small changes in the molecular structure on the supramolecular aggregation. The unbalanced hydrogen‐bond acceptor/donor ratio, greater in (II) than in (I), does not result in the inclusion of water molecules in the structure. 相似文献
9.
Dorcas M. M. Farrell George Ferguson Alan J. Lough Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(8):955-957
In the title compound, C4H12N22+·2C8H7O3?·2CH4O, the cations lie across centres of inversion and are disordered over two orientations with equal occupancy; there are equal numbers of (R)‐ and (S)‐mandelate anions present (mandelate is α‐hydroxybenzeneacetate). The anions and the neutral water molecules are linked by O—H?O hydrogen bonds [O?O 2.658 (3) and 2.682 (3) Å, and O—H?O 176 and 166°] into deeply folded zigzag chains. Each orientation of the cation forms two symmetry‐related two‐centre N—H?O hydrogen bonds [N?O 2.588 (4) and 2.678 (4) Å, and N—H?O 177 and 171°] and two asymmetric, but planar, three‐centre N—H?(O)2 hydrogen bonds [N?O 2.686 (4)–3.137 (4) Å and N—H?O 137–147°], and by means of these the cations link the anion/water chains into bilayers. 相似文献
10.
Takahito Itoh Masato Miyachi Masataka Kubo 《Journal of polymer science. Part A, Polymer chemistry》1999,37(9):1285-1292
2,5‐Bis(dicyanomethylene)‐2,5‐dihydrofuran (TCNF) is not homopolymerizable with any initiators, but copolymerizable with styrene (St) in an alternating fashion. Reactivity of TCNF was compared with that of 2,5‐bis(dicyanomethylene)‐2,5‐dihydrothiophene (TCNT) on the basis of the terpolymerization of the TCNT‐TCNF‐St system and the rates of addition reactions of AIBN with TCNT and with TCNF. TCNF was found to be lower in reactivity than TCNT. The relative reactivity was explained with the energy difference between quinonoid structure and benzenoid one. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 1285–1292, 1999 相似文献
11.
David J. Wiedenfeld Vladimir N. Nesterov Mark A. Minton David R. Glass 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(12):o700-o702
Bis(2,5‐dimethoxy‐4‐methylphenyl)methane, C19H24O4, (IIa), was obtained and characterized as a minor product from the reaction of toluhydroquinone dimethyl ether (1,4‐dimethoxy‐2‐methylbenzene) with N‐(hydroxymethyl)trifluoroacetamide. Similarly, bis(2,5‐dimethoxy‐3,4,6‐trimethylphenyl)methane, C23H32O4, (IIb), was prepared from the corresponding reaction of trimethylhydroquinone dimethyl ether (2,5‐dimethoxy‐1,3,4‐trimethylbenzene). The molecules of (IIa) and (IIb) each lie on a twofold axis passing through the methylene group. The dihedral angle between the planar phenyl rings is 73.4 (1)° in (IIa) and 77.9 (1)° in (IIb). The external bond angles around the bridging methylene group are 116.6 (2) and 117.3 (2)° for (IIa) and (IIb), respectively. In (IIa), the methoxy substituents lie in the plane of the ring and are conjugated with the aromatic system, whereas in (IIb), they are almost perpendicular to the phenyl ring and are positioned on opposite sides. 相似文献
12.
13.
Yoichiro Iwase Koichi Kondo Kenji Kamada Koji Ohta 《Journal of polymer science. Part A, Polymer chemistry》2002,40(20):3534-3541
1,4‐Bis(4‐benzylpyridinium)butadiyne triflate was aggregated in dimethylformamide and spontaneously converted into the 1,4‐addition type of polydiacetylene. The polymerization took place in a dipolar aprotic solvent with a large dielectric constant that could enhance the aggregation of the ionic diacetylene salt through the electrostatic interaction. The molecular weight of the diacetylene was leveled off after 30 h at 80 °C to reach 1.5 × 104 (number‐average molecular weight) that consisted of the 1,4‐addition type of polydiacetylene similar to polydiacetylenes obtained in the conventional solid‐state polymerization. Electron spin resonance spectra revealed that diradicals were generated at the earlier state aggregation to give rise to a solution polymerization. The UV spectra also suggested the presence of the activated aggregation associated with the polymerization as well as the eximer emission spectra. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3534–3541, 2002 相似文献
14.
William Clegg Todd B. Marder Sylvain Nlate Andrew J. Scott 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(10):o603-o605
The title compound, C36H26B4F24N2O6·0.667C4H10O, has centrosymmetric tetraboradioxane molecules, half each of three of these comprising the asymmetric unit together with a molecule of diethyl ether. Disorder affects most of the CF3 groups and one ethyl group of the solvent molecule. The B4O2 rings are approximately planar and contain two B atoms with trigonal geometry and two with distorted tetrahedral geometry, the B—O bonds for the four‐coordinate B atoms being longer than those for the three‐coordinate B atoms. N—H...O hydrogen bonds link two of the crystallographically independent molecules together in chains, while the third molecule forms discrete trimolecular clusters with two solvent molecules via N—H...O hydrogen bonds. This is the first crystallographically characterized example of a tetrabora‐dioxane molecule containing both four‐ and three‐coordinate B atoms. 相似文献
15.
Zhen‐Feng Zhang Jian‐Hua Qin Si‐Qian Wang Gui‐Rong Qu 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(11):o622-o625
In 2,2,2‐trichloro‐N,N′‐bis(4‐methoxyphenyl)ethane‐1,1‐diamine, C16H17Cl3N2O2, molecules are linked into helical chains by N—H...O hydrogen bonds. Molecules of 2,2,2‐trichloro‐N,N′‐bis(4‐chlorophenyl)ethane‐1,1‐diamine, C14H11Cl5N2, are connected into a three‐dimensional framework by two independent Cl...Cl interactions and one C—H...Cl hydrogen bond. 相似文献
16.
Gene‐Hsiang Lee 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(5):o241-o244
The molecule of N,N′‐bis(4‐pyridylmethyl)oxalamide, C14H14N4O2, (I) or 4py‐ox, has an inversion center in the middle of the oxalamide group. Adjacent molecules are then linked through intermolecular N—H...N and C—H...O hydrogen bonds, forming an extended supramolecular network. 4,4′‐{[Oxalylbis(azanediyl)]dimethylene}dipyridinium dinitrate, C14H16N4O22+·2NO3−, (II), contains a diprotonated 4py‐ox cation and two nitrate counter‐anions. Each nitrate ion is hydrogen bonded to four 4py‐ox cations via intermolecular N—H...O and C—H...O interactions. Adjacent 4py‐ox cations are linked through weak C—H...O hydrogen bonding between an α‐pyridinium C atom and an oxalamide O atom, forming a two‐dimensional extended supramolecular network. 相似文献
17.
Marek Gliski Ewa Wilczkowska Izabela D. Madura Janusz Zachara 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(12):o720-o722
The asymmetric unit of the title compound, C12H18O2, contains two independent molecules. They differ only slightly in conformation but form completely different intermolecular hydrogen‐bonded arrays. One molecule exhibits disorder in the hydroxy group region, but this does not influence the formation of hydrogen bonds. The bulky tert‐butyl group on one side of the carbinol C atom and the benzene ring on the other side promote the formation of discrete dimeric motifs via hydrogen‐bridged hydroxy groups. Dimers are further joined by strong hydroxy–methoxy O—H...O bonds to form chains with dangling alcohol groups. Weaker intermolecular C—H...O interactions mediate the formation of a two‐dimensional network. 相似文献
18.
Graeme J. Gainsford Simon Hinkley 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(6):654-657
Levulinic acid derivatives are potential `green chemistry' renewably sourced molecules with utility in industrial coatings applications. Suitable single crystals of the centrosymmetric title compounds, C14H22O6 and C16H26O6, respectively, were obtained with difficulty. The data for the latter hexane‐1,6‐diyl compound were extracted from the major fragment of a three‐component twinned crystal. Both compounds crystallize in similar‐sized unit cells with identical symmetry, utilizing the same weak nonconventional attractive C—H...O(ketone) hydrogen bonds via C(4) and C(5) motifs, which expand to R22(30) ring and C22(14) chain motifs. Their different packing orientations in similar‐sized unit cells suggest that crystal growth involving packing mixes could lead to intergrowths or twins. 相似文献
19.
Hatem M. Titi Anirban Karmakar Israel Goldberg 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(9):m238-m244
We report the synthesis of the 2,2′‐[2,5‐bis(carboxymethoxy)‐1,4‐phenylene]diacetic acid (TALH4) ligand and the structures of its adducts with ammonium, namely diammonium 2,2′‐[2,5‐bis(carboxymethyl)‐1,4‐phenylenedioxy]diacetate, 2NH4+·C14H12O102−, (I), lanthanum, namely poly[[aquabis[μ4‐2,2′‐(2‐carboxylatomethyl‐5‐carboxymethyl‐1,4‐phenylenedioxy)diacetato]dilanthanum(III)] monohydrate], {[La2(C14H11O10)2(H2O)]·H2O}n, (II), and zinc cations, namely poly[[{μ4‐2,2′‐[2,5‐bis(carboxymethyl)‐1,4‐phenylenedioxy]diacetato}zinc(II)] trihydrate], {[Zn(C14H12O10)]·3H2O}n, (III), and poly[[diaqua(μ2‐4,4′‐bipyridyl){μ4‐2,2′‐[2,5‐bis(carboxymethyl)‐1,4‐phenylenedioxy]diacetato}dizinc(II)] dihydrate], {[Zn2(C14H10O10)(C10H8N2)(H2O)2]·2H2O}n, (IV), the formation of all four being associated with deprotonation of TALH4. Adduct (I) is a diammonium salt of TALH22−, with the ions located on centres of crystallographic inversion. Its crystal structure reveals a three‐dimensional hydrogen‐bonded assembly of the component species. Reaction of TALH4 with lanthanum trinitrate hexahydrate yielded a two‐dimensional double‐layer coordination polymer, (II), in which the LaIII cations are nine‐coordinate. With zinc dinitrate hexahydrate, TALH4 forms 1:1 two‐dimensional coordination polymers, in which every ZnII cation is linked to four neighbouring TALH22− anions and each unit of the organic ligand is coordinated to four different tetrahedral ZnII cation connectors. The crystal structure of this compound accommodates molecules of disordered water at the interface between adjacent polymeric layers to give (III), and it has been determined with low precision. Another polymer assembly, (IV), was obtained when zinc dinitrate hexahydrate was reacted with TALH4 in the presence of an additional 4,4′‐bipyridyl ligand. In the crystal structure of (IV), the bipyridyl and TAL4− entities are located on two different inversion centres. The ternary coordination polymers form layered arrays with corrugated surfaces, with the ZnII cation connectors revealing a tetrahedral coordination environment. The two‐dimensional polymers in (II)–(IV) are interconnected with each other by hydrogen bonds involving the metal‐coordinated and noncoordinated molecules of water. TALH4 is doubly deprotonated, TALH22−, in (I) and (III), triply deprotonated, viz. TALH3−, in (II), and quadruply deprotonated, viz. TAL4−, in (IV). This report provides the first structural characterization of TALH4 (in deprotonated form) and its various supramolecular adducts. It also confirms the potential utility of this tetraacid ligand in the formulation of coordination polymers with metal cations. 相似文献
20.
Sophia Lipstman Israel Goldberg 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(1):o3-o7
The title free base porphyrin compound forms hydrogen‐bonded adducts with N,N‐dimethylformamide, C44H30N4O4·4C3H7NO, (I), a mixture of N,N‐dimethylformamide and water, C44H30N4O4·4C3H7NO·H2O, (II), and a mixture of N,N‐dimethylacetamide and water, C44H30N4O4·6C3H7NO·2H2O, (III). Total solvation of the four hydroxy functions of the porphyrin molecules characterizes all three compounds, thus preventing its supramolecular association into extended network architectures. In (I), the asymmetric unit consist of two five‐component adduct species, while in (III), the nine‐component entities reside on centres of inversion. This report provides the first structural characterizations of the free base tetra(hydroxyphenyl)porphyrin. It also demonstrates that the presence of strong Lewis bases, such as dimethylformamide or dimethylacetamide, in the crystallization mixture prevents direct supramolecular networking of the porphyrin ligands via O—H...O—H hydrogen bonds, due to their competing O—H...N(base) interaction with the hydroxy functions. The crystal packing of compounds (I)–(III) resembles that of other hydrogen‐bonding‐assisted tetraarylporphyrin clathrates. 相似文献