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1.
De‐Lie An Prof. Dr. Ying‐Jun Zhang Qiang Chen Wen‐Ying Zhao Hong Yan Akihiro Orita Prof. Dr. Junzo Otera Prof. Dr. 《化学:亚洲杂志》2007,2(10):1299-1304
New types of enantiopure compounds were synthesized to gain better insight into the structural features of phenylene ethynylene cyclophynes. Besides the previously obtained meta‐substituted arylene ethynylenes, 1 , ortho‐connected phenylene ethynylene units were incorporated to give cyclophynes with ortho/meta and ortho/ortho connection modes, 2 and 3 . Furthermore, a diphenylethyne component was also accommodated in 4 . Both ab initio calculations and NMR spectra suggest a large amount of strain for 2 but less strain for 3 and 1 a , the latter having the smallest ring size among cyclophynes with the meta/meta connection mode. The CD spectra of 2 and 3 showed a characteristic shoulder at around 340 nm, similar to the case of 1 a . This implies that the aromatic acetylene bonds cross over each other in the double‐helical structure. These results indicate that chirality information is useful for probing the persistency of molecular shape. 相似文献
2.
Michel H. C. J. van Houtem Rafael Martín‐Rapún Dr. Jef A. J. M. Vekemans Dr. E. W. Meijer Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(7):2258-2271
Two novel nonsymmetrical disc‐shaped molecules 1 and 2 based on 3,3′‐bis(acylamino)‐2,2′‐bipyridine units were synthesized by means of a statistical approach. Discotic 1 possesses six chiral dihydrocitronellyl tails and one peripheral phenyl group, whereas discotic 2 possesses six linear dodecyloxy tails and one peripheral pyridyl group. Preorganization by strong intramolecular hydrogen bonding and subsequent aromatic interactions induce self‐assembly of the discotics. Liquid crystallinity of 1 and 2 was determined with the aid of polarized optical microscopy, differential scanning calorimetry, and X‐ray diffraction. Two columnar rectangular mesophases (Colr) have been identified, whereas for C3‐symmetrical derivatives only one Colr mesophase has been found. 1 In solution, the molecularly dissolved state in chloroform was studied with 1H NMR spectroscopy, whereas the self‐assembled state in apolar solution was examined with optical spectroscopy. Remarkably, these desymmetrized discotics, which lack one aliphatic wedge, behave similar to the symmetric parent compound. To prove that the stacking behavior of discotics 1 and 2 is similar to that of reported C3‐symmetrical derivatives, a mixing experiment of chiral 1 with C3‐symmetrical 13 has been undertaken; it has shown that they indeed belong to one type of self‐assembly. This helical J‐type self‐assembly was further confirmed with UV/Vis and photoluminescence (PL) spectroscopy. Eventually, disc 2 , functionalized with a hydrogen‐bonding acceptor moiety, might perform secondary interactions with molecules such as acids. 相似文献
3.
Masahiro Ueda Masaki Kimura Shinobu Miyagawa Hikaru Takaya Masaya Naito Yuji Tokunaga 《化学:亚洲杂志》2020,15(14):2212-2217
In this study we synthesized two‐ and four‐armed porphyrins – bearing two carboxyl and four 2‐aminoquinolino functionalities, respectively, at their meso positions – as a complementary hydrogen bonding pair for the self‐assembly of a D2‐symmetric porphyrin trimer host. Two units of the two‐armed porphyrin and one unit of the four‐armed porphyrin self‐assembled quantitatively into the D2‐symmetric porphyrin trimer, stabilized through ammidinium‐carboxylate salt bridge formation, in CH2Cl2 and CHCl3. The porphyrin trimer host gradually bound two units of 1,3,5‐trinitrobenzene between the pair of porphyrin units, forming a five‐layer aromatic structure. At temperatures below ?40 °C, the rates of association and dissociation of the complexes were slow on the NMR spectroscopic time scale, allowing the 1 : 1 and 1 : 2 complexes of the trimer host and trinitrobenzene guest(s) to be detected independently when using less than 2 eq of trinitrobenzene. Vis titration experiments revealed the values of K1 (2.1±0.4×105 M?1) and K2 (2.2±0.06×104 M?1) in CHCl3 at room temperature. 相似文献
4.
Fátima Aparicio Fátima García Prof. Dr. Luis Sánchez 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(9):3239-3248
A systematic study of the influence of solvent and the size of C3‐symmetric discotics on their supramolecular polymerization mechanism is presented. The cooperativity of the self‐assembly of the reported compounds is directly related to their gelation ability. The two series of C3‐symmetric discotics investigated herein are based on benzene‐1,3,5‐tricarboxamides (BTAs) and oligo(phenylene ethynylene)‐based tricarboxamides (OPE? TAs) that are peripherally decorated with achiral ( 1 a and 2 a ) or chiral N‐(2‐aminoethyl)‐3,4,5‐trialkoxybenzamide units ( 1 b and 2 b ). The supramolecular polymerization of compounds 1 a , b and 2 a , b has been exhaustively investigated in a number of solvents and by using various techniques: variable‐temperature circular dichroism (VT‐CD) spectroscopy, concentration‐dependent 1H NMR spectroscopy, and isothermal titration calorimetry (ITC). The supramolecular polymerization mechanism of compounds 2 is highly cooperative in solvents such as methylcyclohexane and toluene and is isodesmic in CHCl3. Unexpectedly, chiral compound 1 b is practically CD‐silent, in contrast with previously reported BTAs. ITC measurements in CHCl3 demonstrated that the supramolecular polymerization of BTA 1 a is isodesmic. These results confirm the strong influence of the π‐surface of the central aromatic core of the studied discotic and the branched nature of the peripheral side chains on the supramolecular polymerization. The gelation ability of these organogelators is negated in CHCl3, in which the supramolecular polymerization mechanism is isodesmic. 相似文献
5.
Time‐Resolved Assembly of Cluster‐in‐Cluster {Ag12}‐in‐{W76} Polyoxometalates under Supramolecular Control
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Caihong Zhan Jamie M. Cameron Jing Gao Jamie W. Purcell De‐Liang Long Leroy Cronin 《Angewandte Chemie (International ed. in English)》2014,53(39):10362-10366
We report the time‐resolved supramolecular assembly of a series of nanoscale polyoxometalate clusters (from the same one‐pot reaction) of the form: [H(10+m)Ag18Cl(Te3W38O134)2]n, where n=1 and m=0 for compound 1 (after 4 days), n=2 and m=3 for compound 2 (after 10 days), and n=∞ and m=5 for compound 3 (after 14 days). The reaction is based upon the self‐organization of two {Te3W38} units around a single chloride template and the formation of a {Ag12} cluster, giving a {Ag12}‐in‐{W76} cluster‐in‐cluster in compound 1 , which further aggregates to cluster compounds 2 and 3 by supramolecular Ag‐POM interactions. The proposed mechanism for the formation of the clusters has been studied by ESI‐MS. Further, control experiments demonstrate the crucial role that TeO32?, Cl?, and Ag+ play in the self‐assembly of compounds 1 – 3 . 相似文献
6.
Dr. Feng Wang Martijn A. J. Gillissen Patrick J. M. Stals Dr. Anja R. A. Palmans Prof. Dr. E. W. Meijer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(37):11761-11770
The design of supramolecular motifs with tuneable stability and adjustable supramolecular polymerisation mechanisms is of crucial importance to precisely control the properties of supramolecular assemblies. This report focuses on constructing π‐conjugated oligo(phenylene ethynylene) (OPE)‐based one‐dimensional helical supramolecular polymers that show a cooperative growth mechanism. Thus, a novel set of discotic molecules comprising a rigid OPE core, three amide groups, and peripheral solubilising wedge groups featuring C3 and C2 core symmetry was designed and synthesised. All of the discotic molecules are crystalline compounds and lack a columnar mesophase in the solid state. In dilute methylcyclohexane solution, one‐dimensional supramolecular polymers are formed stabilised by threefold intermolecular hydrogen bonding and π–π interactions, as evidenced by 1H NMR measurements. Small‐angle X‐ray and light scattering measurements reveal significant size differences between the columnar aggregates of C3‐ and C2‐symmetrical discotics, that is, the core symmetry strongly influences the nature of the supramolecular polymerisation process. Temperature‐dependent CD measurements show a highly cooperative polymerisation process for the C3‐symmetrical discotics. In contrast, the self‐assembly of C2‐symmetrical discotics shows a smaller enthalpy release upon aggregation and decreased cooperativity. In all cases, the peripheral stereogenic centres induce a preferred handedness in the columnar helical aggregates. Moreover, one stereogenic centre suffices to fully bias the helicity in the C2‐symmetrical discotics. Finally, chiral amplification studies with the C3‐symmetrical discotics were performed by mixing chiral and achiral discotics (sergeants‐and‐soldiers experiment) and discotics of opposite chirality (majority‐rules experiment). The results demonstrate a very strong sergeants‐and‐soldiers effect and a rather weak majority‐rules effect. 相似文献
7.
Zhouyang Luo Dr. Ningbo Zhu Prof. Dr. Dahui Zhao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(31):11028-11034
The folding and aggregation behavior of a pair of oligo(phenylene ethynylene) (OPE) foldamers are investigated by means of UV/Vis absorption and circular dichroism spectroscopy. With identical OPE backbones, two foldamers, 1 with alkyl side groups and 2 with triethylene glycol side chains, manifest similar helical conformations in solutions in n‐hexane and methanol, respectively. However, disparate and competing folding and aggregation processes are observed in alternative solvents. In cyclohexane, oligomer 1 initially adopts the helical conformation, but the self‐aggregation of unfolded chains, as a minor component, gradually drives the folding–unfolding transition eventually to the unfolded aggregate state completely. In contrast, in aqueous solution (CH3OH/H2O) both folded and unfolded oligomer 2 appear to undergo self‐association; aggregates of the folded chains are thermodynamically more stable. In solutions with a high H2O content, self‐aggregation among unfolded oligomers is kinetically favored; these oligomers very slowly transform into aggregates of helical structures with greater thermodynamic stability. The folded–unfolded conformational switch thus takes place with the free (nonaggregated) molecules, and the very slow folding transition is due to the low concentration of molecularly dispersed oligomers. 相似文献
8.
Alexander Briceo Reinaldo Atencio Raquel Gil Alejandra Nobrega 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(8):o441-o444
The structure of trans‐3‐(3‐pyridyl)acrylic acid, C8H7NO2, (I), possesses a two‐dimensional hydrogen‐bonded array of supramolecular ribbons assembled via heterodimeric synthons between the pyridine and carboxyl groups. This compound is photoreactive in the solid state as a result of close contacts between the double bonds of neighbouring molecules [3.821 (1) Å] along the a axis. The crystal structure of the photoproduct, rctt‐3,3′‐(3,4‐dicarboxycyclobutane‐1,2‐diyl)dipyridinium dichloride, C16H16N2O42+·2Cl−, (II), consists of a three‐dimensional hydrogen‐bonded network built from crosslinking of helical chains integrated by self‐assembly of dipyridinium cations and Cl− anions via different O—H...Cl, C—H...Cl and N+—H...Cl hydrogen‐bond interactions. 相似文献
9.
Christian Neis Kaspar Hegetschweiler 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(4):396-399
In the title monohydrated cocrystal, namely 1,3‐diamino‐5‐azaniumyl‐1,3,5‐trideoxy‐cis‐inositol iodide–1,3,5‐triamino‐1,3,5‐trideoxy‐cis‐inositol–water (1/1/1), C6H16N3O3+·I−·C6H15N3O3·H2O, the neutral 1,3,5‐triamino‐1,3,5‐trideoxy‐cis‐inositol (taci) molecule and the monoprotonated 1,3‐diamino‐5‐azaniumyl‐1,3,5‐trideoxy‐cis‐inositol cation (Htaci+) both adopt a chair conformation, with the three O atoms in axial and the three N atoms in equatorial positions. The cation, but not the neutral taci unit, exhibits intramolecular O—H...O hydrogen bonding. The entire structure is stabilized by a complex three‐dimensional network of intermolecular hydrogen bonds. The neutral taci entities and the Htaci+ cations are each aligned into chains along [001]. In these chains, two O—H...N interactions generate a ten‐membered ring as the predominant structural motif. The rings consist of vicinal 2‐amino‐1‐hydroxyethylene units of neighbouring molecules, which are paired via centres of inversion. The chains are interconnected into undulating layers parallel to the ac plane, and the layers are further held together by O—H...N hydrogen bonds and additional interactions with the iodide counter‐anions and solvent water molecules. 相似文献
10.
Alexandra I. Costa Luís F. V. Ferreira José V. Prata 《Journal of polymer science. Part A, Polymer chemistry》2008,46(19):6477-6488
A novel fluorescent (p‐phenylene ethynylene)‐calix[4]arene‐based polymer ( CALIX‐PPE ) has been successfully synthesized by cross‐coupling polymerization of bis‐calix[4]arene 1 with 1,4‐diethynylbenzene. The polycondensation was carried out in toluene/NEt3 at 35 °C for 24 h, using PdCl2(PPh3)2/CuI as the catalytic system, furnishing CALIX‐PPE in excellent isolated yields (higher than 95%, several runs). The yellow polymer is freely soluble in several nonprotic organic solvents. The GPC trace of the isolated polymer showed a monomodal distribution and a number‐average molecular weight of 23,300 g mol?1 (Mw/Mn = 2.05). No evidence was found in the structural analysis (FTIR and 1H/13C NMR) regarding the formation of alkyne homocoupled segments along the polymer chain. For comparative purposes, the synthesis of an analogous poly(p‐phenylene ethynylene) containing p‐t‐butyl‐phenoxymethyl side chains ( TBP‐PPE ) was also undertaken. A great similarity was found between the photophysical properties of CALIX‐PPE and TBP‐PPE in solution (UV–vis and laser induced luminescence), clearly demonstrating their unique dependence on the structure and conformation of the conjugated PPE backbone. The fluorescence spectra of polymers are of nearly identical shape, displaying their maximum emission around 420 nm. The calculated solution photoluminescence quantum yields of CALIX‐PPE and TBP‐PPE are of similar magnitude (?F( CALIX‐PPE ) = 0.43; ?F( TBP‐PPE ) = 0.51). © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6477–6488, 2008 相似文献
11.
《Acta Crystallographica. Section C, Structural Chemistry》2018,74(8):967-973
Crystals of poly[[aqua[μ3‐4‐carboxy‐1‐(4‐carboxylatobenzyl)‐2‐propyl‐1H‐imidazole‐5‐carboxylato‐κ5O1O1′:N3,O4:O5][μ4‐1‐(4‐carboxylatobenzyl)‐2‐propyl‐1H‐imidazole‐4‐carboxylato‐κ7N3,O4:O4,O4′:O1,O1′:O1]cadmium(II)] monohydrate], {[Cd2(C15H14N2O4)(C16H14N2O6)(H2O)]·H2O}n or {[Cd2(Hcpimda)(cpima)(H2O)]·H2O}n, (I), were obtained from 1‐(4‐carboxybenzyl)‐2‐propyl‐1H‐imidazole‐4,5‐dicarboxylic acid (H3cpimda) and cadmium(II) chloride under hydrothermal conditions. The structure indicates that in‐situ decarboxylation of H3cpimda occurred during the synthesis process. The asymmetric unit consists of two Cd2+ centres, one 4‐carboxy‐1‐(4‐carboxylatobenzyl)‐2‐propyl‐1H‐imidazole‐5‐carboxylate (Hcpimda2−) anion, one 1‐(4‐carboxylatobenzyl)‐2‐propyl‐1H‐imidazole‐4‐carboxylate (cpima2−) anion, one coordinated water molecule and one lattice water molecule. One Cd2+ centre, i.e. Cd1, is hexacoordinated and displays a slightly distorted octahedral CdN2O4 geometry. The other Cd centre, i.e. Cd2, is coordinated by seven O atoms originating from one Hcpimda2− ligand and three cpima2− ligands. This Cd2+ centre can be described as having a distorted capped octahedral coordination geometry. Two carboxylate groups of the benzoate moieties of two cpima2− ligands bridge between Cd2 centres to generate [Cd2O2] units, which are further linked by two cpima2− ligands to produce one‐dimensional (1D) infinite chains based around large 26‐membered rings. Meanwhile, adjacent Cd1 centres are linked by Hcpimda2− ligands to generate 1D zigzag chains. The two types of chains are linked through a μ2‐η2 bidentate bridging mode from an O atom of an imidazole carboxylate unit of cpima2− to give a two‐dimensional (2D) coordination polymer. The simplified 2D net structure can be described as a 3,6‐coordinated net which has a (43)2(46.66.83) topology. Furthermore, the FT–IR spectroscopic properties, photoluminescence properties, powder X‐ray diffraction (PXRD) pattern and thermogravimetric behaviour of the polymer have been investigated. 相似文献
12.
Yong Cui Jiutong Chen Gang Chen Jing Ren Weichao Yu Yitai Qian 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(4):349-351
A novel centrosymmetric chair‐like dimer, bis(2,2′‐bipyridine)‐1κ2N,N′;3κ2N,N′‐tetra‐μ‐chloro‐1:2κ2Cl;2:3κ2Cl;3:4κ2Cl;1:4κ2Cl‐tetracopper(I), [Cu4Cl4(C10H8N2)2], has been solvothermally synthesized and structurally characterized. The complex self‐assembles into a three‐dimensional network via C—H?Cl hydrogen bonds, π–π stacking and weak Cu?Cl electrostatic interactions. 相似文献
13.
Patrícia D. Barata Alexandra I. Costa Luís F. V. Ferreira José V. Prata 《Journal of polymer science. Part A, Polymer chemistry》2010,48(22):5040-5052
Novel alternating copolymers comprising bis‐ calix[4]arene‐p‐phenylene ethynylene and m‐phenylene ethynylene units ( CALIX‐m‐PPE ) were synthesized using the Sonogashira‐Hagihara cross‐coupling polymerization. Good isolated yields (60–80%) were achieved for the polymers that show Mn ranging from 1.4 × 104 to 5.1 × 104 gmol?1 (gel permeation chromatography analysis), depending on specific polymerization conditions. The structural analysis of CALIX‐m‐PPE was performed by 1H, 13C, 13C–1H heteronuclear single quantum correlation (HSQC), 13C–1H heteronuclear multiple bond correlation (HMBC), correlation spectroscopy (COSY), and nuclear overhauser effect spectroscopy (NOESY) in addition to Fourier transform‐Infrared spectroscopy and microanalysis allowing its full characterization. Depending on the reaction setup, variable amounts (16–45%) of diyne units were found in polymers although their photophysical properties are essentially the same. It is demonstrated that CALIX‐m‐PPE does not form ground‐ or excited‐state interchain interactions owing to the highly crowded environment of the main‐chain imparted by both calix[4]arene side units which behave as insulators inhibiting main‐chain π–π staking. It was also found that the luminescent properties of CALIX‐m‐PPE are markedly different from those of an all‐p‐linked phenylene ethynylene copolymer ( CALIX‐p‐PPE ) previously reported. The unexpected appearance of a low‐energy emission band at 426 nm, in addition to the locally excited‐state emission (365 nm), together with a quite low fluorescence quantum yield (? = 0.02) and a double‐exponential decay dynamics led to the formulation of an intramolecular exciplex as the new emissive species. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
14.
Dr. Jun Yoshida Prof. Dr. Shin‐ichi Nishikiori Prof. Dr. Reiko Kuroda Prof. Dr. Hidetaka Yuge 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(10):3451-3457
We previously reported that monomeric and polymeric metal complexes are obtained from solution and mechanochemical reactions of 3‐cyano‐pentane‐2,4‐dione (CNacacH) with 3d metal acetates (M=MnII, FeII, CoII, NiII, CuII, and ZnII). A common feature found in all complexes was that their structural base is trans‐[M(CNacac)2]. Here, we report that the reactions of CNacacH with CdII acetate in the solution and solid states afford different coordination polymers composed of trans‐[Cd(CNacac)2] and cis‐[Cd(CNacac)2] units, respectively. From a methanol solution containing CNacacH (L) and Cd(OAc)2 ? 2 H2O (M), a coordination polymer ( Cd‐1 ) in which trans‐[Cd(CNacac)2] units are three‐dimensionally linked was obtained. In contrast, two different coordination polymers, Cd‐2 and Cd‐3 , were obtained from mechanochemical reactions of CNacacH with Cd(OAc)2 ? 2 H2O at M/L ratios of 1:1 and 1:2, respectively. In Cd‐2 , cis‐[Cd(CNacac)2] units are two‐dimensionally linked, whereas the units are linked three‐dimensionally in Cd‐3 . Furthermore, Cd‐1 and Cd‐2 converted to Cd‐3 by applying an annealing treatment and grinding with a small amount of liquid, respectively, in spite of the polymeric structures. These phenomena, 1) different structures are formed from solution and mechanochemical reactions, 2) two polymorphs are formed depending on the M/L ratio, and 3) structural transformation of resulting polymeric structures, indicate the usability of mechanochemical method in the syntheses of coordination polymers as well as the peculiar structural flexibility of cadmium‐CNacac polymers. 相似文献
15.
Lusbely M. Belandria Asilo J. Mora Gerzon E. Delgado Alexander Briceo 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(2):o88-o91
The title salt, C6H12NO2+·C6H7O4− or ISO+·CBDC−, is an ionic ensemble assisted by hydrogen bonds. The amino acid moiety (ISO or piperidine‐4‐carboxylic acid) has a protonated ring N atom (ISO+ or 4‐carboxypiperidinium), while the semi‐protonated acid (CBDC− or 1‐carboxycyclobutane‐1‐carboxylate) has the negative charge residing on one carboxylate group, leaving the other as a neutral –COOH group. The –+NH2– state of protonation allows the formation of a two‐dimensional crystal packing consisting of zigzag layers stacked along a separated by van der Waals distances. The layers extend in the bc plane connected by a complex network of N—H...O and O—H...O hydrogen bonds. Wave‐like ribbons, constructed from ISO+ and CBDC− units and described by the graph‐set symbols C33(10) and R33(14), run alternately in opposite directions along c. Intercalated between the ribbons are ISO+ cations linked by hydrogen bonds, forming rings described by the graph‐set symbols R66(30) and R42(18). A detailed analysis of the structures of the individual components and the intricate hydrogen‐bond network of the crystal structure is given. 相似文献
16.
Qiu‐Ying Huang Wei Liu Yi Yang Xiang‐Ru Meng 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(11):1017-1021
Multidentate N‐heterocyclic compounds form a variety of metal complexes with many intriguing structures and interesting properties. The title coordination polymer, catena‐poly[zinc(II)‐bis{μ‐2‐[(1H‐imidazol‐1‐yl)methyl]‐1H‐benzimidazole}‐κ2N3:N3′;N3′:N3‐zinc(II)‐bis(μ‐benzene‐1,2‐dicarboxylato)‐κ2O1:O2;κ3O1,O1′:O2], [Zn2(C8H4O4)2(C11H10N4)2]n, has been synthesized by the reaction of Zn(NO3)2 with 2‐[(1H‐imidazol‐1‐yl)methyl]‐1H‐benzimidazole (imb) and benzene‐1,2‐dicarboxylic acid (H2bdic) under hydrothermal conditions. There are two crystallographically distinct imb ligands [imb(A) and imb(B)] in the structure which adopt very similar coordination geometries. The imb(A) ligand bridges two symmetry‐related Zn1 ions, yielding a binuclear [(Zn1)2{imb(A)}2] unit, and the imb(B) ligand bridges two symmetry‐related Zn2 ions resulting in a binuclear [(Zn2)2{imb(B)}2] unit. The above‐mentioned binuclear units are further connected alternately by pairs of bridging bdic2− ligands, forming an infinite one‐dimensional chain. These one‐dimensional chains are further connected through N—H...O hydrogen bonds, leading to a two‐dimensional layered structure. In addition, the title polymer exhibits good fluorescence properties in the solid state at room temperature. 相似文献
17.
Cigdem Hopa Ismail Cokay 《Acta Crystallographica. Section C, Structural Chemistry》2016,72(2):149-154
The design and synthesis of polymeric coordination compounds of 3d transition metals are of great interest in the search for functional materials. The coordination chemistry of the copper(II) ion is of interest currently due to potential applications in the areas of molecular biology and magnetochemistry. A novel coordination polymer of CuII with bridging N,N′‐bis(2‐hydroxyphenyl)‐2,2‐dimethylpropane‐1,3‐diamine (H2L‐DM) and dicyanamide (dca) ligands, catena‐poly[[[μ2‐2,2‐dimethyl‐N,N′‐bis(2‐oxidobenzylidene)propane‐1,3‐diamine‐1:2κ6O,N,N′,O′:O,O′]dicopper(II)]‐di‐μ‐dicyanamido‐1:2′κ2N1:N5;2:1′κ2N1:N5], [Cu2(C19H20N2O2)(C2N3)2]n, has been synthesized and characterized by CHN elemental analysis, IR spectroscopy, thermal analysis and X‐ray single‐crystal diffraction analysis. Structural studies show that the CuII centres in the dimeric asymmetric unit adopt distorted square‐pyramidal geometries, as confirmed by the Addison parameter (τ) values. The chelating characteristics of the L‐DM2− ligand results in the formation of a CuII dimer with a double phenolate bridge in the asymmetric unit. In the crystal, the dimeric units are further linked to adjacent dimeric units through μ1,5‐dca bridges to produce one‐dimensional polymeric chains. 相似文献
18.
The metal‐organic framework {[Zn2(CAM)(μ2‐OH)(bpp)] · 2H2O}n ( 1 ) [H3CAM = 4‐hydroxypyridine‐2,6‐dicarboxylic acid, bpp = 1,3‐bis(4‐pyridyl)propane], was hydrothermally synthesized and characterized by elemental analyses, infrared spectroscopy, and single‐crystal X‐ray diffraction. Compound 1 presents a three dimensional self‐penetrating 8‐connected framework with the Schläfli symbol 420.53.65. In addition, the fluorescent properties and thermal stability of 1 were discussed as well. 相似文献
19.
Genivaldo Júlio Perptuo Jan Janczak 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(5):o271-o273
Crystals of the title compound, C4H8N5+·C2F3O2−, are built up of singly protonated 2,4‐diamino‐6‐methyl‐1,3,5‐triazin‐1‐ium cations and trifluoroacetate anions. The CF3 group of the anion is disordered. The oppositely charged ions interact via almost linear N—H...O hydrogen bonds, forming a CF3COO−...C4H8N5+ unit. Two units related by an inversion centre interact through a pair of N—H...N hydrogen bonds, forming planar (CF3COO−...C4H8N5+...C4H8N5+·CF3COO−) aggregates that are linked by a pair of N—H...O hydrogen bonds into chains running along the c axis. 相似文献
20.
Jianmin Li Xianping Deng Zhiyong Zhang Yafei Wang Yu Liu Keqi He Ying Huang Qiang Tao Lixia Quan Weiguo Zhu 《Journal of polymer science. Part A, Polymer chemistry》2012,50(22):4686-4694
A class of the 9,9‐dioctylfluorene‐alt‐5,7‐bis(thiophen‐2‐yl)‐2,3‐biphenylthieno [3,4‐b]pyrazine copolymeric derivatives (PFO‐3ThPz‐D) attaching additional donor (D) units in the pendant phenyl ring with a D‐A D structure was synthesized and investigated, where the additional D unit is a substituent group of fluorene, carbazole, and triphenylamine (Tpa). Their photovoltaic properties were significantly tuned by these pending donor units. Among these copolymers, the PFO‐3ThPz‐Tpa exhibited the best photovoltaic properties in the bulk heterojunction polymeric solar cells (BHJ‐PSC). The maximum power conversion efficiency (PCE) of 2.09% and the highest circuit current density (Jsc) of 7.91 mA/cm2 were obtained in the cell using a blend of PFO‐3ThPz‐Tpa and PC60BM (1:3, w/w) as active layer, which are 2.5 and 1.8 times higher than those corresponding levels in the other cell using the parent PFO‐3ThPz‐Ph copolymer instead of PFO‐3ThPz‐Tpa as donor, respectively. While PC60BM was replaced by PC70BM, the PFO‐3ThPz‐Tpa‐based BHJ‐PSC exhibited better photovoltaic properties with PCE of 3.08% and Jsc of 10.3 mA/cm2. This work demonstrated that attaching donor units into the D‐A‐based copolymeric side‐chain is a simple and effective method to improve the photovoltaic properties for the resulting copolymers. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献