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1.
A novel three‐dimensional framework of 2‐[(1H‐imidazol‐1‐yl)methyl]‐1H‐benzimidazole dihydrate, C11H10N4·2H2O or L·2H2O, (I), in which L acts as both hydrogen‐bond acceptor and donor in the supramolecular construction with water, has been obtained by self‐assembly reaction of L with H2O. The two independent water molecules are hydrogen bonded alternately with each other to form a one‐dimensional infinite zigzag water chain. These water chains are linked by the benzimidazole molecules into a three‐dimensional framework, in which each organic molecule is hydrogen bonded by three water molecules. This study shows that the diversity of hydrogen‐bonded patterns plays a crucial role in the formation of the three‐dimensional framework. More significantly, as water molecules are important in contributing to the conformation, stability, function and dynamics of biomacromolecules, the infinite chains of hydrogen‐bonded water molecules seen in (I) may be a useful model for water in other chemical and biological processes.  相似文献   

2.
In the title complex, [Ni(H2O)6](C6H10N2O6PS)2·6H2O, the asymmetric unit consists of one‐half of an Ni atom (which lies on an inversion centre) with three coordinated water molecules, one complete 2‐carboxylato‐2‐(isothiouronium‐S‐ylmethyl)propane‐1,3‐diyl phosphate anion and three noncoordinated water molecules. The hexaaquanickel(II) cations have distorted octahedral coordination and are connected via water chains to form two‐dimensional supramolecular networks parallel to the ab plane. The phosphate ester anion is linked via N—H...O and O—H...O hydrogen bonds, thus creating various ring, dimer and chain hydrogen‐bonding patterns, and building up a second two‐dimensional supramolecular network parallel to the ab plane. The crystal structure is further stabilized by an intra‐ and interlayer hydrogen‐bond network. This work illustrates that a carboxylate with a caged phosphate ester can open its ring in the presence of dichloridotetrakis(thiourea)nickel, and the resulting polyfunctional anion can be used for constructing a complex hydrogen‐bonding scheme.  相似文献   

3.
采用水热法设计合成了两个新型三维超分子化合物H2L·H2O (1)和[Ag(bpy)2]·HL·H2O (2) (其中bpy=2,2'-联吡啶, H2L=2,4′-二羧基二苯甲酮),晶体结构分析表明,它们均是通过氢键采用不同的连接方式拓展而成。其中,化合物1 是2,4′-二羧基二苯甲酮和水分子通过O–H···O氢键形成的一维梯状链扩展构筑的三维超分子体系;化合物2 则是2,4′-二羧基二苯甲酮和水分子通过两种氢键形成含有一维隧道的三维超分子体系。有趣的是,[Ag(bpy)2]+ 阳离子通过π–π 堆积和弱的Ag···Ag相互作用连在一起,进而以客体形式填充其中。荧光性质研究表明,由于存在bpy的螯合与堆积效应,化合物2相比配体和化合物1,其荧光发射峰发生红移。  相似文献   

4.
Single crystals of a new polymorph of 1,4‐bis(imidazol‐1‐ylmethyl)benzene dihydrate (bix·2H2O), C14H14N4·2H2O, have been obtained by the hydrothermal method. The asymmetric unit is composed of two independent half‐bix molecules, one on an inversion center and one on a twofold axial site, and two water molecules. The disordered water molecules link into discrete tetrameric water units via two O—H...O hydrogen bonds, forming planar R44(8) rings. These tetrameric water units and bix molecules are further linked by two O—H...N hydrogen bonds into a three‐dimensional network in which an (106) hydrogen‐bonded ring is observed. These large rings lead to the formation of a fivefold interpenetrated network. If both the tetrameric water units and the bix molecules can be regarded as connected nodes, one single three‐dimensional net can then be rationalized as a CdSO4 network. This study indicates that topological methodology can be applied in some cases in order to understand the inherent characteristics of some hydrogen‐bonded supramolecular assemblies.  相似文献   

5.
Introduction Optically active 1,1'-bi-2-naphthol (BINOL) and its derivatives have been widely used as chiral ligands of catalysts for asymmetric reactions and effective host compounds for the isolation or optical resolution of a wide range of organic guest molecules through the for-mation of crystalline inclusion complexes.1,2 The wide-ranging and important applications of these com-pounds in organic synthesis have stimulated great inter-est in developing efficient methods for their prepara-…  相似文献   

6.
Halogen bonding has been used to glue together hydrogen‐bonded short arylamide foldamers to achieve new supramolecular double and quadruple helices in the solid state. Three compounds, which bear a pyridine at one end and either a CF2I or fluorinated iodobenzene group at the other end, engage in head‐to‐tail N???I halogen bonds to form one‐component supramolecular P and M helices, which stack to afford supramolecular double‐stranded helices. One of the double helices can dimerize to form a G‐quadruplex‐like supramolecular quadruple helix. Another symmetric compound, which bears a pyridine at each end, binds to ICF2CF2I through N???I halogen bonds to form two‐component supramolecular P and M helices, with one turn consisting of four (2+2) molecules. Half of the pyridine‐bearing molecules in two P helices and two M helices stack alternatingly to form another supramolecular quadruple helix. Another half of the pyridine‐bearing molecules in such quadruple helices stack alternatingly with counterparts from neighboring quadruple helices, leading to unique quadruple helical arrays in two‐dimensional space.  相似文献   

7.
The crystal structure of the title compound, {[Tm(C8H3O7S)(H2O)5]·1.5C10H8N2·0.5H2O}n, is built up from two [Tm(SIP)(H2O)5] molecules (SIP3− is 5‐sulfonatobenzene‐1,3‐dicarboxylate), three 4,4′‐bipyridyl (bpy) molecules and one solvent water molecule. One of the bpy molecules and the solvent water molecule are located on an inversion centre and a twofold rotation axis, respectively. The TmIII ion coordination is composed of four carboxylate O atoms from two trianionic SIP3− ligands and five coordinated water molecules. The Tm3+ ions are linked by the SIP3− ligands to form a one‐dimensional zigzag chain propagating along the c axis. The chains are linked by interchain O—H...O hydrogen bonds to generate a two‐dimensional layered structure. The bpy molecules are not involved in coordination but are linked by O—H...N hydrogen bonds to form two‐dimensional layers. The two‐dimensional layers are further bridged by the bpy molecules as pillars and the solvent water molecules through hydrogen bonds, giving a three‐dimensional supramolecular structure. π–π stacking interactions between the parallel aromatic rings, arranged in an offset fashion with a face‐to‐face distance of 3.566 (1) Å, are observed in the crystal packing.  相似文献   

8.
Crystals of the title compound, 2C3H7N6+·C10H6O6S22−·C3H6N6·5H2O, are built up of neutral 2,4,6‐triamino‐1,3,5‐triazine (melamine), singly protonated melaminium cations, naphthalene‐1,5‐disulfonate dianions and water molecules. Two independent anions lie across centres of inversion in the space group P. The melamine molecules are connected by N—H...N hydrogen bonds into two different one‐dimensional polymers almost parallel to the (010) plane, forming a stacking structure along the b axis. The centrosymmetric naphthalene‐1,5‐disulfonate anions interact with water molecules via O—H...O hydrogen bonds, forming layers parallel to the (001) plane. The cations and anions are connected by N—H...O and O—H...N hydrogen bonds to form a three‐dimensional supramolecular framework.  相似文献   

9.
采用缓慢蒸发法以2-硝基-苯-1,4-二氧二乙酸为柔性配体合成新型多孔配位聚合物[Ca(nbdo)(H2O)2] n,并对其进行元素、红外光谱、X-射线单晶衍射、DSC、TG-DTG和荧光光谱的分析测试。晶体结构显示为一维微孔结构,由于四种形式的氢键的存在使晶胞堆积形成了三维超分子网络结构。热分析表明该化合物在375K时失去了水分子,当温度升高到了550K时,配位聚合物的网状结构出现了破坏。荧光光谱分析测试表明该化合物在室温固体状态下320nm处具有较强的荧光性。  相似文献   

10.
Mixtures of 4‐carboxypyridinium perchlorate or 4‐carboxypyridinium tetrafluoroborate and 18‐crown‐6 (1,4,7,10,13,16‐hexaoxacyclooctadecane) in ethanol and water solution yielded the title supramolecular salts, C6H6NO2+·ClO4·C12H24O6·2H2O and C6H6NO2+·BF4·C12H24O6·2H2O. Based on their similar crystal symmetries, unit cells and supramolecular assemblies, the salts are essentially isostructural. The asymmetric unit in each structure includes one protonated isonicotinic acid cation and one crown ether molecule, which together give a [(C6H6NO2)(18‐crown‐6)]+ supramolecular cation. N—H...O hydrogen bonds between the protonated N atoms and a single O atom of each crown ether result in the 4‐carboxypyridinium cations `perching' on the 18‐crown‐6 molecules. Further hydrogen‐bonding interactions involving the supramolecular cation and both water molecules form a one‐dimensional zigzag chain that propagates along the crystallographic c direction. O—H...O or O—H...F hydrogen bonds between one of the water molecules and the anions fix the anion positions as pendant upon this chain, without further increasing the dimensionality of the supramolecular network.  相似文献   

11.
The title porphyrin compound forms hydrogen‐bonded adducts with methanol (1:1), [Pd(C48H28N4O8)]·CH4O, (I), and with water and N,N‐dimethylformamide (1:4:4), [Pd(C48H28N4O8)]·4C3H7NO·4H2O, (II). In (I), the metalloporphyrin unit lies across a mirror plane in Cmca, while in (II), this unit lies across an inversion center in P. Extended supramolecular hydrogen‐bonded arrays are formed in (I) by intermolecular interactions between the carboxylic acid functions, either directly or through the methanol species. These layers have a wavy topology and large interporphyrin pores, which are filled in the crystal structure by double interpenetration as well as enclathration of additional non‐interacting nitrobenzene solvent molecules. The supramolecular aggregation in (II) can be characterized by cascaded porphyrin layers, wherein adjacent porphyrin molecules are hydrogen bonded to one another through molecules of water that are incorporated into the hydrogen‐bonding scheme. Molecules of dimethylformamide partly solvate the carboxylic acid groups and fill the interporphyrin space in the crystal structure.  相似文献   

12.
The metal complexes [Cu(NO3)2(H2O)2(H2azbpz)2] · 2H2O ( 1 ) and [Ni(H2O)4(H2azbpz)2](NO3)2 · 2H2O ( 2 ) of 4,4′‐azobis(3,5‐dimethyl‐1H‐pyrazole) (H2azbpz) incorporate the bipyrazole as a monodentate ligand and are associated into supramolecular architectures by hydrogen bonds and azo‐pz π interactions in the solid state. In 1 a cis configuration is integrated and the NH function adjacent to the metal‐coordinating nitrogen atom gives rise to a seven‐membered anion‐assisted hydrogen‐bonded ring around the central metal atom bringing the NH function in endo‐position to the azo‐bridge. The interplay of hydrogen‐bonds and dimeric azo‐pz π interactions in 1 forms one‐dimensional supramolecular chains, which are further interconnected by a heterodromic D2h symmetric tetrameric water ring. In 2 a trans form of H2azbpz is mono‐coordinated and the synergy of hydrogen‐bonded rings around the central metal atom and continuous azo‐pz π interactions form a two‐dimensional supramolecular network structure. The supramolecular packings of 1 and 2 is further underpinned by the analysis of their Hirshfeld surface areas.  相似文献   

13.
Chiral coordination polymers have attracted intense interest mainly due to their potential applications. Hence, two new chiral copper(II) coordination polymers {[Cu(tsgluO)(H2O)]2·3H2O}n ( 1 ) and [Cu(tsgluO)(2,2′‐bipy)]n ( 2 ) (H2tsglu?(+)‐N‐tosyl‐l‐glutamic acid; 2,2′‐bipy?2,2′‐bipyridine) were synthesized in the absence or presence of 2,2′‐bipy ligand and structurally characterized. A single crystal X‐ray diffraction study revealed that compound 1 consists of a paddle‐wheel dicopper(II) core, which links other equivalents via four tsgluO2? ligands to form a 1D double chain. Such a chain is further interconnected through weak π‐π stacking and hydrogen bonding interactions to form a 3D H‐bonded supramolecular structure with 1D channels hosting lattice water molecules. Whereas, compound 2 , containing the coordinating 2,2′‐bipy, gives rise to a ladder‐like 1D double chain. Antiferromagnetic interactions were observed in 1 and 2 .  相似文献   

14.
3‐tert‐Butyl‐7‐(4‐methoxybenzyl)‐4′,4′‐dimethyl‐1‐phenyl‐4,5,6,7‐tetrahydro‐1H‐pyrazolo[3,4‐b]pyridine‐5‐spiro‐1′‐cyclohexane‐2′,6′‐dione, C31H37N3O3, (I), 3‐tert‐butyl‐7‐(2,3‐dimethoxybenzyl)‐4′,4′‐dimethyl‐1‐phenyl‐4,5,6,7‐tetrahydro‐1H‐pyrazolo[3,4‐b]pyridine‐5‐spiro‐1′‐cyclohexane‐2′,6′‐dione, C32H39N3O4, (II), 3‐tert‐butyl‐4′,4′‐dimethyl‐7‐(3,4‐methylenedioxybenzyl)‐1‐phenyl‐4,5,6,7‐tetrahydro‐1H‐pyrazolo[3,4‐b]pyridine‐5‐spiro‐1′‐cyclohexane‐2′,6′‐dione, C31H35N3O4, (III), and 3‐tert‐butyl‐4′,4′‐dimethyl‐1‐phenyl‐7‐(3,4,5‐trimethoxybenzyl)‐4,5,6,7‐tetrahydro‐1H‐pyrazolo[3,4‐b]pyridine‐5‐spiro‐1′‐cyclohexane‐2′,6′‐dione ethanol 0.67‐solvate, C33H41N3O5·0.67C2H6O, (IV), all contain reduced pyridine rings having half‐chair conformations. The molecules of (I) and (II) are linked into centrosymmetric dimers and simple chains, respectively, by C—H...O hydrogen bonds, augmented only in (I) by a C—H...π hydrogen bond. The molecules of (III) are linked by a combination of C—H...O and C—H...π hydrogen bonds into a chain of edge‐fused centrosymmetric rings, further linked by weak hydrogen bonds into supramolecular arrays in two or three dimensions. The heterocyclic molecules in (IV) are linked by two independent C—H...O hydrogen bonds into sheets, from which the partial‐occupancy ethanol molecules are pendent. The significance of this study lies in its finding of a very wide range of supramolecular aggregation modes dependent on rather modest changes in the peripheral substituents remote from the main hydrogen‐bond acceptor sites.  相似文献   

15.
The title compounds, (4H‐chromeno[4,3‐c]isoxazol‐3‐yl)methanol, C11H9NO3, (I), and (8‐methyl‐4H‐chromeno[4,3‐c]isoxazol‐3‐yl)methanol monohydrate, C12H11NO3·H2O, (II), crystallize in the monoclinic space groups P21/c and C2/c, respectively. The simple addition of a methyl substituent in (II) results in a change in the structure type and substantially alters the intermolecular interaction patterns, while retaining the point‐group symmetry 2/m. Compound (II) crystallizes as a hydrate and the resulting hydrogen‐bonding interactions involving the water molecule are the cause of differences in the hydrogen‐bonded supramolecular motifs present in (I) and (II). The water molecule in (II) is disordered over two positions having very similar orientations, with occupancies of 0.571 (18) and 0.429 (18), although the pattern of hydrogen‐bonding interactions for the two disordered water molecules remains essentially the same. In both compounds, the primary donor hydroxy group adopts a trans conformation with respect to the isoxazole O atom, with a torsion angle of 170.65 (8)° for (I) and 179.56 (10)° for (II), the small difference being due to differences in the hydrogen‐bonding environment of the hydroxy group. In (I), molecules are linked through two independent O—H...N and C—H...O hydrogen bonds and form sheets of centrosymmetric R44(18) and R44(14) rings extending parallel to the (100) plane. The supramolecular motifs in (II) generate two‐dimensional sheets parallel to the (100) plane through a combination of O—H...X (X = N, O) and C—H...O hydrogen bonds, leading to water‐assisted noncentrosymmetric R22(8) and R66(20) motifs. The present work is an example of how the simple replacement of a substituent in the main molecular scaffold may transform the structure type, paving the way for a variety of supramolecular motifs and consequently altering the complexity of the intermolecular interaction patterns.  相似文献   

16.
In (2SR,4RS)‐7‐chloro‐2‐exo‐(4‐chlorophenyl)‐2,3,4,5‐tetrahydro‐1H‐1,4‐epoxy‐1‐benzazepine, C16H13Cl2NO, (I), the molecules are linked by a combination of C—H...O and C—H...N hydrogen bonds into a chain of edge‐fused R33(12) rings. The isomeric compound (2S,4R)‐7‐chloro‐2‐exo‐(2‐chlorophenyl)‐2,3,4,5‐tetrahydro‐1H‐1,4‐epoxy‐1‐benzazepine, (II), crystallizes as a single 2S,4R enantiomer and the molecules are linked into a three‐dimensional framework structure by two C—H...O hydrogen bonds and one C—H...π(arene) hydrogen bond. The molecules of (2S,4R)‐7‐chloro‐2‐exo‐(1‐naphthyl)‐2,3,4,5‐tetrahydro‐1H‐1,4‐epoxy‐1‐benzazepine, C20H16ClNO, (III), are also linked into a three‐dimensional framework structure, here by one C—H...O hydrogen bond and two C—H...π(arene) hydrogen bonds. The significance of this study lies in its observation of the variations in molecular configuration and conformation, and in the variation in the patterns of supramolecular aggregation, consequent upon modest changes in the peripheral substituents.  相似文献   

17.
The crystal structure of the title compound, C10H10N2O2·H2O, also known as l ‐5‐benzylhydantoin monohydrate, is described in terms of two‐dimensional supramolecular arrays built up from infinite chains assembled via N—H...O and O—H...O hydrogen bonds among the organic molecules and solvent water molecules, with graph‐set R33(10)C(5)C22(6). The hydrogen‐bond network is reinforced by stacking of the layers through C—H...π interactions.  相似文献   

18.
Crystal structures are reported for three fluoro‐ or chloro‐substituted 1′‐deoxy‐1′‐phenyl‐β‐D‐ribofuranoses, namely 1′‐deoxy‐1′‐(2,4,5‐trifluorophenyl)‐β‐D‐ribofuranose, C11H11F3O4, (I), 1′‐deoxy‐1′‐(2,4,6‐trifluorophenyl)‐β‐D‐ribofuranose, C11H11F3O4, (II), and 1′‐(4‐chlorophenyl)‐1′‐deoxy‐β‐D‐ribofuranose, C11H13ClO4, (III). The five‐membered furanose ring of the three compounds has a conformation between a C2′‐endo,C3′‐exo twist and a C2′‐endo envelope. The ribofuranose groups of (I) and (III) are connected by intermolecular O—H...O hydrogen bonds to six symmetry‐related molecules to form double layers, while the ribofuranose group of (II) is connected by O—H...O hydrogen bonds to four symmetry‐related molecules to form single layers. The O...O contact distance of the O—H...O hydrogen bonds ranges from 2.7172 (15) to 2.8895 (19) Å. Neighbouring double layers of (I) are connected by a very weak intermolecular C—F...π contact. The layers of (II) are connected by one C—H...O and two C—H...F contacts, while the double layers of (III) are connected by a C—H...Cl contact. The conformations of the molecules are compared with those of seven related molecules. The orientation of the benzene ring is coplanar with the H—C1′ bond or bisecting the H—C1′—C2′ angle, or intermediate between these positions. The orientation of the benzene ring is independent of the substitution pattern of the ring and depends mainly on crystal‐packing effects.  相似文献   

19.
Much attention has been paid by chemists to the construction of supramolecular coordination compounds based on the multifunctional ligand 5‐sulfosalicylic acid (H3SSA) due to the structural and biological interest of these compounds. However, no coordination compounds have been reported for the multifunctional amino‐substituted sulfobenzoate ligand 2‐amino‐5‐sulfobenzoic acid (H2asba). We expected that H2asba could be a suitable building block for the assembly of supramolecular networks due to its interesting structural characteristics. The reaction of cadmium(II) nitrate with H2asba in the presence of the auxiliary flexible dipyridylamide ligand N,N′‐bis[(pyridin‐4‐yl)methyl]oxamide (4bpme) under ambient conditions formed a new mixed‐ligand coordination compound, namely bis(3‐amino‐4‐carboxybenzenesulfonato‐κO1)diaquabis{N,N′‐bis[(pyridin‐4‐yl)methyl]oxamide‐κN}cadmium(II)–N,N′‐bis[(pyridin‐4‐yl)methyl]oxamide–water (1/1/4), [Cd(C7H6NO5S)2(C14H14N4O2)2(H2O)2]·C14H14N4O2·4H2O, (1), which was characterized by single‐crystal and powder X‐ray diffraction analysis (PXRD), FT–IR spectroscopy, thermogravimetric analysis (TG), and UV–Vis and photoluminescence spectroscopic analyses in the solid state. The central CdII atom in (1) occupies a special position on a centre of inversion and exhibits a slightly distorted octahedral geometry, being coordinated by two N atoms from two monodentate 4bpme ligands, four O atoms from two monodentate 4‐amino‐3‐carboxybenzenesulfonate (Hasba) ligands and two coordinated water molecules. Interestingly, complex (1) further extends into a threefold polycatenated 0D→2D (0D is zero‐dimensional and 2D is two‐dimensional) interpenetrated supramolecular two‐dimensional (4,4) layer through intermolecular hydrogen bonding. The interlayer hydrogen bonding further links adjacent threefold polycatenated two‐dimensional layers into a three‐dimensional network. The optical properties of complex (1) indicate that it may be used as a potential indirect band gap semiconductor material. Complex (1) exhibits an irreversible dehydration–rehydration behaviour. The fluorescence properties have also been investigated in the solid state at room temperature.  相似文献   

20.
The title compounds, p‐phenetidinium hydrogen phthalate (or 4‐ethoxyanilinium 2‐carboxybenzoate), C8H12NO+·C8H5O4, (I), and cyclohexylaminium hydrogen phthalate hemihydrate (or cyclohexylaminium 2‐carboxybenzoate hemihydrate), C6H14N+·C8H5O4·0.5H2O, (II), form two‐ and one‐dimensional supramolecular networks, respectively. In (I), the anionic–cationic network consists of R32(6) and R44(16) hydrogen‐bonded rings forming a two‐dimensional sheet along the (001) plane. In (II), O—H...O hydrogen bonds connect the glide‐related anions, generating a supramolecular chain running parallel to [001] to which the cations are linked to form one‐dimensional channels along [001]. The solvent water molecules, which reside on twofold axes, are trapped inside the molecular channels by N—H...O and O—H...O hydrogen bonds.  相似文献   

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