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1.
Summary N,N′-Pyromelliticdiimido-di-L-methionine (1), N,N′-Pyromelliticdiimido-di-L-alanine (2), N,N′-Pyromelliticdiimido-di-L-phenylalanine (3) , and N,N′-Pyromelliticdiimido-di-L-leucine (4) were prepared from the reaction of Pyromellitic dianhydride with corresponding L-amino acids in a mixture of glacial acetic acid and pyridine solution (3/2 ratio) under refluxing conditions. The phosphorylation polycondensation of the corresponding diimide-diacid monomers with 4-phenyl-2,6-bis(4-aminophenyl) pyridine (6) or 4-(p-methylthiophenyl)-2,6-bis(4-aminophenyl) pyridine (8) were carried out in N-methyl-2-pyrolidone (NMP). The resulting poly (amide-imide)s were obtained in quantitative yields, showed admirable inherent viscosities (0.20-0.97 dl g-1), were soluble in polar aprotic solvents, showed good thermal stability and high optical purity. The synthetic compounds were characterized by IR, MS, 1H NMR and 13C NMR spectroscopy, elemental analysis and specific rotation.  相似文献   

2.
A Zn(II) metal–organic framework with nano-sized channels from 4,4′-bipyridine (4,4′-bipy) and 4′-sulfo-biphenyl-4-carboxylate (sbpc2−) ligands, {[Zn(μ-4,4′-bipy)1.5(μ-sbpc)]·5H2O} n (1), has been synthesized by the hydrothermal method. Compound 1 was characterized by X-ray powder diffraction, IR spectroscopy, elemental analysis and single-crystal X-ray crystallography. The structural studies show the Zn atoms have a six-coordinate geometry with a distorted octahedral environment constructed of paddle-wheel [Zn2(OOC)4] building units with 4,4′-bipy and sbpc2− linkers stacked over each other to generate three-dimensional nano-sized channels occupied by guest H2O molecules.  相似文献   

3.
Four novel compounds [Co(Hdpa) 2(4,4′-bipy)2]n (1), {[Ni(dpa)(2,2′-bipy)(H2O)](H2O)}n, (2), [Ni(dpa)(im)3]n (3) and [Zn(dpa)(im)]n (4) [H2dpa = 2,4′-diphenyl-dicarboxylic acid, 4,4′-bipy = 4,4′-bipyridine, 2,2′-bipy = 2,2′-bipyridine and im = imidazole] were synthesized and characterized by elemental analysis, IR and single-crystal X-ray diffraction. X-ray crystallography shows that the 2,4′-diphenic acid exhibits three coordination modes to link the metal ions: μ 1 η1: η1/μ 0 η0: η0, μ 1η 1: η 0/μ 2η 1: η 1 and μ 1η 1: η 0/μ 1η 1: η 0. Compound 1 has a 1D supramolecular structure. Compounds 2 and 3 are 3D supramolecular structures. Compound 4 is a 2D supramolecular structure. All the compounds, 14, are self-assembled to form supramolecular structures through hydrogen bonding interactions.  相似文献   

4.
Characterization and synthesis of novel cyano bridged coordination compounds [Ni(bishydeten)Pt(CN)4] (1), [Cu(bishydeten)Pt(CN)4] (2), [Zn(bishydeten)Pt(CN)4] (3), [Cd(bishydeten)Pt(CN)4] (4) [bishydeten = N,N′-bis(2-hydroxyethyl)ethylenediamine (C6H16N2O2)] were reported herein. The IR spectra of these coordination compounds verified the formation of aforementioned complexes. The ground state of the paramagnetic electron in the CuII located in tetragonal distorted octahedral sites (D 4h ) was found to be dx2−y2 for complex 2. As for complex 1, an EPR signal was not observed because of diamagnetic property of the PtII and momentary relaxation times of the NiII. All complexes followed identical decomposition mechanism in thermal analysis and thermal stabilities of complexes changed in the order of 1 > 4 > 3 > 2. Both 3 and 4 exhibit polymeric structure according to X-ray single structure analysis. While bishydeten coordinated with three donor atoms (N,N′, and O) in complex 3, it acts as a bidentate ligand (N, and N′) in complex 4. Magnetic properties of complexes 12 at 15–300 K temperature range were determined as antiferromagnetic with Weiss constants = −2.619 and −0.847 K respectively.  相似文献   

5.

Abstract  

Three novel inorganic–organic hybrid frameworks of [Cu(BPDC)(2,2′-bipy)] (1), [Cu(BPDC)(BIB)2 ·H2O]n (2) and [Cu(BPDC)(4,4′-bipy)]n (3) (BPDC2− = 2,2′-bipyridine-3,3′-dicarboxylate; 2,2′-bipy = 2,2′-bipyridine; BIB = 1,2-bis(imidazol-1-ylmethyl)benzene; 4,4′-bipy = 4,4′-bipyridine) were prepared. The three complexes have been characterized by the elemental analyses, IR spectra, TGA and the single crystal X-ray diffraction. Two intramolecular Cu(II) centers of 1 are encircled by two BPDC2− ligands forming an 18-membered ring, which is further assembled into a three-dimensional (3D) supramolecular architecture through the C–H···O hydrogen-bonding interactions. Complex 2 possesses a two-dimensional layer network, while complex 3 is a three-dimensional polymer composed of Cu-BPDC helical chains bridged by 4,4′-bipy. In addition, the electrochemistry of complex 1 was investigated.  相似文献   

6.
Two new metal coordination polymers [Zn2(dpa)2(bpa)] (1) and [Ni4(dpa)4(bpa)3] (2) [H2dpa = 2,4′-biphenyldicarboxylic acid and bpa = 1,2-bis(4-pyridyl)ethane] have been synthesized and structurally characterized by elemental analysis, IR and X-ray diffraction. Single-crystal X-ray diffraction analysis reveals that complex 1 shows a 2D (4,4) topological net and complex 2 features a 3D network with (4.62)2(42.610.83) topology. Fluorescent study of complex 1 shows that it has an emission at 414 nm in the solid state at room temperature.  相似文献   

7.
Three new coordination polymers, [Ni(2,4′-oba)(1,10-phen)] n (1), {[Ni (2,4′-Hoba)2(4,4′-bipy)(H2O)2]·2H2O} n (2) and [Zn(2,4′-oba) (4,4′-bipy)] n (3) (2,4′-H2oba = 2-(4-carboxyphenoxy)benzoic acid, 1,10- phen = 1,10-phenanthroline, and 4,4′-bipy = 4,4′-bipyridine) have been obtained by hydrothermal synthesis. The framework structures of these polymeric complexes have been determined by single-crystal X-ray diffraction studies. Complex 1 exhibits double-helical chains formed by ππ stacking interactions from the phenyl rings of the 1,10-phen ligands. Complex 2 forms a two-dimensional supramolecular architecture directed by hydrogen bonding. Complex 3 exhibits a three-dimensional structure; Schl?fli symbol of {44·610·8}. The luminescent property of compound 3 is discussed.  相似文献   

8.
Wu ZP  Chen Y  Xia B  Wang M  Dong YF  Feng X 《Lipids》2009,44(1):63-70
Two novel ceramides, Candidamide A (1) with a phytosphingolipid structure, and Candidamide B (2) with a tertiary amide structure, together with 12 known compounds (3–14) have been isolated from the bulbs of Zephyranthes candida, The structures of 1 and 2 have been elucidated to be 1,3,5,6-tetrahydroxy-2-(2′-hydroxytetracosanoyl amino)-8-(E)-octadecadiene (1) and (2S,3S,4R,8E,2′R)-2-[N-(2′-hydroxyoctadecanoyl)-N-(1′′,2′′-dihydroxyethyl)-amino]-8-hexacosene-1,3,4-triol (2) on the basis of spectroscopic evidence including IR, MS, NMR (1H-NMR, 13C-NMR, DEPT, 1H–1H COSY, HSQC, HMBC). The known compounds were identified as (2S)-3′,7-dihydroxy-4′-methoxyflavan (3), (2S)-4′-hydroxy-7-methoxyflavan (4), (2S)-4′,7-dihydroxyflavan (5), 7-hydroxy-3′, 4′-methylenedioxyflavan (6), ambrettolide (7), β-sitostero1 (8), β-daucosterin (9), rutin (10), pancratistatin (11), lycorine (12), haemanthidine (13), and haemanthamine (14). In the antimicrobial assay, candidamide A (1) and candidamide B (2) displayed moderate activities against bacteria Staphylococcus aureus and Escherichia coli, and fungi Aspergillus niger, Candida albicans and Trichophyton rubrum.  相似文献   

9.
Two novel inorganic–organic hybrid frameworks of [Co(2,5-pydc)(4,4′-bipyo)0.5(H2O)3 · 3H2O] n (1) and [Cu1.5Gd(2,5-pydc)3(2,2′-bipyo)(H2O)4 · 2H2O] n (2) (2,5-pydc = pyridine-2,5-dicarboxylic acid; 4,4′-bipyo = 4,4′-bipyridine-N,N′-dioxide; 2,2′-bipyo = 2,2′-bipyridine-N,N′-dioxide) were prepared. Both compounds have been characterized by the elemental analyses, IR spectra, TG analysis and the single crystal diffraction. The salient structural feature for both compounds 1 and 2 is that the 1D chain and the mononuclear fragment are connected by strong hydrogen bond interactions to form 2D structure.  相似文献   

10.
A sandwich-like 2D infinite framework of {[Cd(pbbm)2(SO3FcSO3)]·(CH3OH)2·(H2O)6} n (1) with nanosized porous structure [Fc(SO3)2Na2 = ferrocene-1,1′-disulphonate, pbbm = 1,1′-(1,3-propylene)-bis-1H-benzimidazole] was prepared by combining d 10 Cd2+ ions with highly conjugated pbbm and disodium ferrocene-1,1′-disulfonate. Experimental results show that 1 could serve as a new fluorescent probe for the detection of many divalent metal ions in water, such as Mn2+, Fe2+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+, Ag+, Cd2+, Hg2+ and Pb2+, and trace organic solvents, including acetone, toluene, methylene chloride, ether, tetrahydrofuran, and methanol. The main product was very different from previous chemosensory materials that only identify one or two metal ions. The powdery multipurpose chemosensory materials proposed here could also sequester dangerous heavy metal ions, especially Pb2+. A computational study of ferrocene-1,1′-disulfonate and 1 gave insight into the process of ion exchange and sorption. This study introduces a promising new field of fluorescent chemosensors based on nanoporous coordination polymers with free functional groups.  相似文献   

11.
The ethynylene-bridged ferrocene-anthraquinone system exhibits unique protonation-induced electron transfer reactions to form multi-dentate valence tautomerization states. In this study, we newly synthesized ethynylene-bridged ferrocene-anthraquinone alternating oligomers by a reaction of 1,1′-bis(trimethylstannylethynyl)ferrocene with 1,8-dibromoanthraquinone in the presence of a Pd(0) catalyst. An insoluble 1:1-donor/acceptor polymer, (1,1′-Fc-1,8-Aq) n , was obtained and characterized by IR and UV-vis spectra and elemental analysis. The molecular weight of the soluble portion of the oligomers was M w = 2.6 × 103 (M w/M n = 1.4). A cyclic dimer, cyclic -(FcAq) 2 , was also obtained and characterized by the 2D-NMR spectra. The behavior of the insoluble polymer (1,1′-Fc-1,8-Aq) n upon the addition of an organic acid such as CF3SO3H was examined and compared with that of the monomer exposed to the same conditions. The addition of CF3SO3H to the insoluble polymer rendered soluble in organic solvent, and the changes in the UV-vis-NIR and IR absorption spectra reflected the structural changes to the protonated form with valence tautomers; this reaction was similar to the reactions with 1-ferrocenylethynylanthraquinone (1-FcAq) and 1,8-bis(ferrocenylethynyl)anthraquinone (1,8-Fc 2 Aq). This paper is dedicated to Professor Ian Manners and his scientific accomplishments.  相似文献   

12.
The direct polycondensations of cubane-1,4-dicarboxylic acid with 1,4-phenylenediamine (2 a), 4,4′-oxydianiline (2 b), 4,4′-sulfonyldianiline (2 c), and 9,9′-bis(4-aminophenyl)florene (2 d) were carried out in N-methyl-2-pyrrolidone/pyridine containing triphenylphosphite and lithium chloride at 110 °C for 9 h. Polyamide 3 a obtained from 2 a was scarcely soluble in organic solvent even during heating, and was soluble only in conc-H2SO4, whereas 3 c and 3 d derived from 2 c and 2 d, respectively, were readily soluble in N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, and dimethylsulfoxide. After treating polyamide 3 d with the rhodium complex catalyst in NMP, cubane units were quantitatively converted into cyclooctatetraenes. Received: 3 March 1997/Accepted: 1 April 1997  相似文献   

13.
Summary N,N-(3,3,4,4-benzophenonetetracarboxylic)-3,3,4,4-diimido-di-L-methionine (3) was prepared from the reaction of 3,3,4,4-benzophenonetetracarboxylic-3,3,4,4-dianhydride (1) with L-methionine (2) in a solution of (glacial acetic acid/pyridine) at refluxing temperature. The phosphorylation polycondensation of the diimide-diacid monomer (3) with 1,3-phenylenediamine (4a), 1,4-phenylenediamine (4b), 2,6-diaminopyridine (4c), 3,5-diaminopyridine (4d), 4,4-diaminobiphenyl (4e) and 4,4-diaminodiphenylsulfone (4f) was carried out in N-methyl-2-pyrolidone (NMP). The resulting poly (amide-imide)s showed admirable moderate inherent viscosities (0.23–0.48 dl g-1), good thermal stability and improved optical activity. All of the above compounds were fully characterized by IR spectroscopy, elemental analysis and specific rotation. Some structural characterization and physical properties of these new poly (amide-imide)s are presented.  相似文献   

14.
Rational self-assembly of a flexible ligand 3,3′,4,4′-benzophenonetetracarboxylic acid and d10 transition metal salts in the presence of rigid bidentate ligand 1,10-phenanthroline yields two novel helical coordination polymers with different structural motifs; i.e., [Zn(H2bbtc)(phen)2 · 2H2O] n (1) and [Cd2(bbtc)(phen)4 · 2.25H2O] n (2) (H4bbtc = 3,3′,4,4′-benzophenonetetracarboxylic acid, phen = 1,10-phenanthroline), under solvothermal condition. One is hydrogen bonded and π–π stacked together into a network, and the other is a covalently coordinated 3D framework. The coordination polymers were characterized by FT-IR, UV/VIS and fluorescent spectroscopy, single crystal X-ray diffraction, elemental analysis and differential thermal analysis/thermogravimetry (DTA/TG). The most intriguing structural feature is that each complex exhibits novel helical-spaced chains by reason of two different ligands coordinating to the metal centers. Additionally, compounds 1 and 2 showed good fluorescence properties compared to the free ligands.  相似文献   

15.
A novel MoV–YbIII bimetallic chain, {[YbIII(bpy)2(DMF)(H2O)][MoV(CN)8]·0.5bpy·4.5H2O}n (1) (DMF = N,N′-dimethylformamide; bpy = 2,2′-bipyridine), has been constructed by the reaction of [Mo(CN)8]3− with Yb3+ and 2,2′-bipyridine. Complex 1 is confirmed as a host–guest supramolecular structure by X-ray structural analysis. The neighboring chains interact with each other with two types of hydrogen bonds and two types of π···π interactions. Thus complex 1 has a unique 3D network. Magnetic analysis of 1 indicates the presence of a strong YbIII single-ion effect owing to spin–orbital coupling within this system.  相似文献   

16.
Three new coordination polymers [Cd(L)(4,4′-bipy)0.5]n (1), {[Mn(L)(bpp)]·H2O}n (2) and [Ni(L)(2,2′-bipy)(H2O)2]n(3) [H2L = Benzopenone-2,4′-dicarboxylic acid, 4,4′-bipy = 4,4′-bipy ridine, bpp = 1,3-di(4-pyridyl) propane and 2,2′-bipy = 2,2′-bipyridine] have been synthesized and structurally characterized by elemental analysis, IR and X-ray diffraction. Single-crystal X-ray analyses revealed that the H2L ligand acts as a bridge, exhibiting three coordination modes to link metal ion: bidentate chelating, bis-monodentate, monodentate. Compound 1 has 3-connected metal–organic framework with the (63) topology notation; Compounds 2 and 3 are one-dimensional chain structures. The luminescent properties for compound 1 was investigated.  相似文献   

17.

Abstract  

The chiral Salen-type Schiff base ligand H 2 L (H 2 L = (s)-(+)2,2′-bis(2-hydroxy-3-methoxybenzylideneamino)-1,1′-binaphthyl), was selected to obtain the new chiral Cu2+ complex CuL (1), which was found to catalyze the polymerization of norbornene (NBE). The complex shows the distinctively distorted geometry from a square-planar reactive center, this feature being suggested to account for the efficient catalysis on the vinylic-type polymerization of NBE, with moderate molecular weights and narrow molecular weight distributions.  相似文献   

18.

Abstract  

A new bipod polyaromatic acid ligand H2bcm (H2bcm = {2, 4-bis [(2′-carboxyphenoxy) methyl]-1,3,5-trimethylbenzene}) is prepared and its two novel binuclear coordination compounds, [Cu2(bcm)2(CH3OH)2]·2CH3OH (1) and [Cu2(bcm)2(CH3CH2OH)2]·2CH3CH2OH (2), have been synthesized with copper acetate and H2bcm ligand in methanol solvent and ethanol solvent respectively, and characterized by the element analysis, IR, TGA and single crystal X-ray diffraction. The results of structural analysis indicate that 1 crystallizes in the triclinic system with space group P1, while 2 crystallizes in the monoclinic system with space group P21 /c. Furthermore, 1 adopts μ 2 -COO and synsyn coordination mode with Cu (II)···Cu (II) separation of 2.5868(11) ? and forms 1D zigzag chain structure by O···O interactions. The coordination of 2 is similar to that of 1 except that ethanol molecules are coordinated instead of methanol molecules with Cu (II)···Cu (II) separation of 2.5973(13) ?. Two-dimensional network structures of 1 and 2 are formed through π–π interactions.  相似文献   

19.
A new group of nonionics, so-called sugar surfactants having a gemini structure, N,N′-bisalkyl-N,N′-bis[(3-gluconylamido)propyl]ethylenediamines [bis(C n GA): C n =n-C8H17, n-C12H25], N,N′-bisdodecyl-N,N′-bis[(3-glucoheptonylamido)propyl]ethylenediamine [bis(C12GH)], and N,N′-bisalkyl-N,N′-bis[(3-lactobionylamido)propyl]ethylenediamines [bis(C n LA): C n =n-C8H17, n-C12H25], were prepared in a convenient four-step procedure from easily accessible reagents. Their structure and purity were confirmed by means of elemental analysis, electrospray ionization MS (ESI-MS), and NMR spectra—1H, 13C, 1H−13C COSY, and distortionless enhancement by polarization transfer. All tested surfactants were practically nontoxic to gram-negative bacteria and fungi, but they inhibited the growth of some gram-positive bacteria. From the results of the Closed Bottle test (OECD Guideline 301D) for biodegradability measurements, it was concluded that the tested aldonamide gemini structures are biodegraded by environmental microorganisms to 16–55% of the initial levels by day 28, the extent depending on both the aldonamide type and the alkyl chain length. Consequently, N,N′-bisalkyl-N,N′-bis[(3-aldonylamido)propyl]ethylenediamines are a surfactant class having low ecotoxicity and fulfilling requirements desired from an ecological standpoint.  相似文献   

20.
Asymmetric anionic polymerizations of achiral N-substituted maleimide (RMI) (N-cyclohexyl (CHMI), N-phenyl (PhMI), N-tert-butyl (TBMI)) by n-butyllithium (n-BuLi) or fluorenyllithium (FlLi) complexes of chiral bisoxazoline derivatives in toluene gave optically active polymers ([α]25 435− 2.9° to − 8.2°). The polymers prerared with initiator of n-BuLi – 2,2′-bis(4,4′-isopropyl-,3-oxazoline) showed negative specific rotations (poly(RMI), [α]25 435− 5.8° to − 8.2°) which were greater than those ([α]25 435− 2.9° to − 5.9°) with other chiral 2,2′-bis(4,4′-alkyl-1,3-oxazoline) (alkyl group = iso-butyl and benzyl). Received: 29 July 1997/Revised: 27 August 1997/Accepted: 1 September 1997  相似文献   

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