- Metallogels and Silver Nanoparticles Generated from a Series of Transition Metal-Based Coordination Polymers Derived from a New Bis-pyridyl-bis-amide Ligand and Various Carboxylates
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A new series of coordination polymers, namely, CP2 [{(H2O)Co1.5(μ-3-bpna)1.5(μ-btc)}·3DMF·3H2O]α, CP3 [{Cd(μ-3-bpna)(μ-hbtc)}·CH3OH·2H2O]α, CP4 [{Co(μ-3-bpna)(μ-ipa)}·DMF·2H2O]α, CP5 [{Co(μ-3-bpna)(μ-1,3-pda)}·DMF]α, CP6 [Cd(μ-3-bpna)0.5(μ-1,3-pda)]α, CP7 [(H2O)Co0.5(μ-3-bpna)0.5(μ-1,4-pda)0.5]α, and CP8 [{Zn(μ-3-bpna)(μ-oba)}·DMF·2H2O]α, has been synthesized by reacting a hydrogen-bond-functionalized bis-pyridyl ligand, namely, N′,N″-di(pyridin-3-yl)naphthalene-2,6-dicarboxamide, with various transition metal salts and different di- or tricarboxylates (as co-ligand) displaying 2D and 3D network topology and having lattice-occluded solvents in the majority of cases. A 1D coordination polymer, namely, CP1 [{Ag0.5(μ-3-bpna)}0.5·0.5BF4·CH3CN]α, has also been isolated by reacting 3-bpna with AgBF4 in the absence of any carboxylate co-ligand. All of the CPs were characterized by single crystal X-ray diffraction. Interestingly, two such CPs, namely, CP1 and CP2, produced metallogels, which were characterized by rheology, transmission electron microscopy, and X-ray powder diffraction. The metallogel of CP1 produced Ag nanoparticles within the gel bed upon exposure to light. (Chemical Equation Presented).
- Nath, Karabi,Husain, Ahmad,Dastidar, Parthasarathi
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- Electronic Coupling between Two Covalently Bonded Dimolybdenum Units Bridged by a Naphthalene Group
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Using 2,6-naphthalenedicarboxylate and its thiolated derivatives as bridging ligands, three Mo2 dimers of the type [Mo2(DAniF)3](E2CC10H6CE2)[Mo2(DAniF)3] (DAniF = N,N′-di-p-anisylformamidinate; E = O, S) have been synthesized and characterized by X-ray diffraction. These compounds can be generally formulated as [Mo2]-naph-[Mo2], where the complex unit [Mo2] ([Mo2(DAniF)3(μ-E2C)]) functions as an electron donor (acceptor) and the naphthalene (naph) group is the bridge. The mixed-valence (MV) complexes, generated by one-electron oxidation of the neutral precursors, display weak, very broad intervalence charge-transfer absorption bands in the near-to-mid-IR regions. The electronic coupling matrix elements for the MV complexes, Hab = 390-570 cm-1, are calculated from the Mulliken-Hush equation, which fall between those for the phenyl (ph) and biphenyl (biph) analogues reported previously. The three series consisting of three complexes with the same [Mo2] units exhibit exponential decay of Hab as the bridge changes from ph to biph via naph, with decay factors of 0.21-0.17 ?-1. Therefore, it is evidenced that while the extent of the bridge conjugacy varies, the electronic coupling between the two [Mo2] units is dominated by the Mo2···Mo2 separation. The absorption band energies for metal-to-ligand charge transfer are in the middle of those for the ph and biph analogues, which is consistent with variation of the HOMO-LUMO energy gaps for the complex series. These results indicate that the interplay of the bridge length and conjugacy is to affect the enegy for charge transfer crossing the intervening moiety, in accordance with a superechange mechanism.
- Zhu, Guang Yuan,Meng, Miao,Tan, Ying Ning,Xiao, Xuan,Liu, Chun Y.
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Read Online
- With high planarity of the naphthalene structure function diamine monomer and its synthetic method and application
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The invention discloses functional diamine monomers having high planarity and containing a naphthaline structure and a synthesis method and application thereof. The novel functional diamine monomers are prepared from raw materials monomers such as dihalogenated naphthaline, naphthalic acid, naphthalenediol or naphthylenediamine through a series of chemical reactions such as substitution reaction, Suzuki reaction, amidation reaction, esterification reaction, Grignard reaction, Kumada coupling reaction. The diamine monomers containing a naphthaline structure, which have a lowest energy state 3D molecular structure and have high planarity, can be obtained. Due to planar space structure, the diamine monomers disclosed by the invention can serve as monomers used for preparing polymers with strong molecular chain interaction force, tight molecular chain packing and small free volume and the polymers can be endowed with an excellent barrier property. The synthesis method of the diamine monomers is simple in process and purification operation is easy; therefore, the synthesis method is suitable for industrial production. The diamine monomers disclosed by the invention can be used for synthesizing functional polymers such as polyamide, polyimide, polyamide-imide and polyester-imide.
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Paragraph 0040; 0041; 0042
(2017/08/25)
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- Self-assembled Pd6L4 cage and Pd4L4 square using hydrazide based ligands: Synthesis, characterization and catalytic activity in Suzuki-Miyaura coupling reactions
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A discrete Pd6L4Td-symmetric molecular cage and a discrete Pd4L4 square assembly were obtained using a coordination-driven self-assembly technique. The assembly, Pd6L4, was prepared via a face-directed method, utilising a 'cis-clipped' palladium(ii) species and a new C3 symmetric tripodal hydrazinic ligand. The Pd4L4 square assembly was prepared via an edge directed method, using the 'cis-clipped'-palladium(ii) species and a new C2 symmetric dipodal hydrazinic ligand. Both assemblies were characterised using multinuclear NMR and ESI-MS spectroscopic techniques and elemental analysis. The size of the assemblies were assigned from HR-TEM measurements, while DOSY NMR analysis established the presence of single component species in solution. Optimised structures obtained using Hartree-Fock calculations are in conformity with the experimental results. Both the assemblies show significant catalytic activity as heterogeneous catalysts for Suzuki-Miyaura coupling reactions under mild, aerobic and phosphine free conditions in aqueous ethanolic medium.
- Pradhan, Subhashis,John, Rohith P.
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p. 12453 - 12460
(2016/02/12)
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- Method of manufacturing imidoyl diazidosulfochloride compd. various compd. and manufacturing method of using the same
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PROBLEM TO BE SOLVED: To provide a new production method for synthesizing an imidoyl chloride compound dispensing with chlorination agents having poor handleability, to provide a method for producing various compounds in high yield and purity by using the imidoyl chloride compound, and to provide a method for isolating the imidoyl chloride compound in high efficiency and purity from a mixture of the imidoyl chloride compound and a phthalic anhydride compound.SOLUTION: The method for producing the imidoyl chloride compound comprises reaction of a specific amide compound with a specific phthaloyl chloride compound to produce a specific imidoyl chloride compound.
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Paragraph 0059
(2016/12/16)
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- New preparation method for Vilsmeier reagent and related imidoyl chlorides
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An environmentally benign and inexpensive preparation method is described of some imidoyl chlorides, including the Vilsmeier reagent (VR), by using phthaloyl dichloride. Synthetic applications were demonstrated using the isolated VR or VR prepared in situ for the transformation of acids to acid chlorides, alcohols to chlorides, and the formylation of dimethylaminobenzene.
- Kimura, Yoshikazu,Matsuura, Daisuke,Hanawa, Takeshi,Kobayashi, Yukimoto
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experimental part
p. 1116 - 1118
(2012/03/26)
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- Enantioselective annulation reactions of bisenolates prepared through dearomatization reactions of aromatic and heteroaromatic diesters
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A one-pot, enantioselective strategy for the dearomatization-annulation of aromatic diesters to give a range of highly functionalized polycyclic molecules with excellent enantioselectivity is presented. This methodology is based on the reaction of bisenolates, prepared by treating aromatic diesters with trialkyltin lithium reagents, which involves a stanna-Brook rearrangement, with 1,ω-dihaloalkanes and other biselectrophiles. We have also developed experimental conditions for performing these reactions with substoichiometric amounts of the required tin reagent by in situ recycling of Me 6Sn2 into Me3SnLi with excess lithium metal, and provide a study of the scope and limitations of this synthetic methodology. The alkylation of chiral bisenolates opens a straightforward one-pot access to highly functionalized bicyclic compounds from aromatic diesters. A stanna-Brook rearrangement originates the key bisenolate intermediate. Copyright
- Perez-Vazquez, Jaime,Veiga, Alberte X.,Prado, Gustavo,Sardina, F. Javier,Paleo, M. Rita
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supporting information; experimental part
p. 975 - 987
(2012/04/04)
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- A palladium-catalyzed multicomponent coupling approach to π-conjugated oligomers: Assembling imidazole-based materials from imines and acyl chlorides
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Just like tinkertoys: An alternative approach to access imidazole-containing π-conjugated materials is presented. The imidazole core was assembled at the same time as the oligomer by the palladium-catalyzed multicomponent coupling of imines, diimines, and di(acyl chloride)s, thus providing access to families of new conjugated materials, each formed in a one-step, catalytic reaction (see scheme; Ts=4-toluenesulfonyl). Copyright
- Siamaki, Ali R.,Sakalauskas, Marc,Arndtsen, Bruce A.
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supporting information; experimental part
p. 6552 - 6556
(2011/09/13)
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- NOVEL INHIBITORS OF HEPATITIS C VIRUS REPLICATION
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The embodiments provide compounds of the general Formulae I, II, III, IV, or V as well as compositions, including pharmaceutical compositions, comprising a subject compound. The embodiments further provide treatment methods, including methods of treating a hepatitis C virus infection and methods of treating liver fibrosis, the methods generally involving administering to an individual in need thereof an effective amount of a subject compound or composition.
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Page/Page column 259-260
(2011/07/06)
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- Self-assembly of porphyrin-azulene-porphyrin and porphyrin-azulene conjugates
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In this paper we report the synthesis and self-assembling behavior of new porphyrin-azulene-porphyrin and porphyrin-azulene conjugates. The porphyrin-azulene-porphyrin conjugate gelates a number of organic solvents, while the porphyrin-azulene conjugates form vesicles in a chloroform-methanol binary mixture. The structures of the organogels and vesicles have been characterized by SEM and AFM. Two porphyrin-naphthalene-porphyrin and porphyrin-naphthalene conjugates were also prepared. A comparison of their properties with those of the azulene analogues reveals that the intermolecular dipole-dipole interaction of the azulene units plays an important role in promoting the self-assembly of the porphyrin-azulene-porphyrin and porphyrin-azulene conjugates. The Royal Society of Chemistry 2009.
- Xiao, Ze-Yun,Zhao, Xin,Jiang, Xi-Kui,Li, Zhan-Ting
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experimental part
p. 2540 - 2547
(2009/10/31)
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- Cross-linked bis-hemoglobins: Connections and oxygen binding
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Covalently linked pairs of cross-linked hemoglobin tetramers ("bis-tetramers", shown schematically as 6-8) were prepared by reacting hemoglobin A with tetrakis acyl phosphate esters (3-5). The effects of the link between tetramers are observed in the oxygen-binding properties of the bis-tetramers: they bind oxygen cooperatively but with Hill coefficients (n 50) lower than that of the native protein and with a high average affinity. The bis-tetramers with longer connections between tetramers show a higher n50, suggesting that steric interactions between the tetramers affect cooperativity. These results correlate to the observed reduced vasoactivity of heterogeneous solutions of oligomeric cross-linked hemoglobin tetramers.
- Gourianov, Nikolai,Kluger, Ronald
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p. 10885 - 10892
(2007/10/03)
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- Method for production of halogen-containing aromatic compound
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This invention relates to a method for the production of an aromatic compound (II) having a (CH2)nCX2Br group (wherein X represents a fluorine or chlorine atom and the X's may be same or different, and n is an integer in the range of 0 to 4) by the reaction of photo-bromination of an aromatic compound (I) having a (CH2)nCX2H group (wherein X and n are as defined above) with a brominating agent, wherein the photo-bromination reaction is carried out while removing hydrogen bromide generated in the reaction system and/or in an atmosphere of a low oxygen content, and a halogen-containing naphthalene compound represented by the following formula (1): wherein Y represents —CF2H, —CF2Br, or —CHO group, Z1and Z2independently represent a halogen atom, and p and q independently are an integer in the range of 0 to 3.
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- Liquid crystal compound
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The novel liquid crystal compounds of the present invention are represented by the following formulas ?I!-?II! and have tristable molecular orientation states and can be used for display devices and electrooptical devices. STR1 wherein R1 represents an alkyl group of 5-18 carbon atoms; R2 represents an alkyl group of 6-16 carbon atoms; R3 represents an alkyl group of 8-18 carbon atoms; R4 represents an alkyl group of 6-14 carbon atoms; Y represents STR2 and * indicates an optically active center.
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- Systematically cross-linked human hemoglobin: Functional effects of 10 ? spans between beta subunits at lysine-82
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The structure and properties of hemoglobin are altered by the introduction of cross-links of defined structure between specific residues. The bis methyl phosphates and bis 3,5-dibromosalicylates of 4-carboxy-trans-cinnamic acid as well as the bis methyl phosphate of 2,6-naphthalenedicarboxylic acid produce a 10 ? cross-link between the ε-amino groups of each β-lys-82 of human hemoglobin. The oxygen affinity of the modified proteins fits the correlation interpolated from those for shorter and longer cross-links. The oxygen binding curve shows a high degree of cooperativity. These results support the idea that the length of the semirigid cross-link in a structurally homogeneous series constrains the relaxation of the protein upon oxygen binding by a mechanism that is specifically reflected in the oxygen affinity, while interactions between hemes that affect cooperativity are not diminished.
- Kluger, Ronald,Shen, Lixin,Xiao, Hong,Jones, Richard T.
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p. 8782 - 8786
(2007/10/03)
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- Liquid crystal compounds
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Antiferroelectric liquid crystal compounds are provided which have the formula STR1 wherein R1 represents an alkyl group having 5-18 carbon atoms, R2 represents an alkyl group having 6-16 carbon atoms, Y represents a group STR2 and A represents a group STR3
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- Naphthalenedicarboxylic acid esters
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Optically active dopants of the formula STR1 wherein C* denotes a chiral carbon atom and R1 signifies C2 -C12 -alkyl, C2 -C12 -alkenyl, C2 -C12 -alkoxycarbonyl or C3 -C12 -alkenyloxycarbonyl, their manufacture, liquid crystalline mixtures which contain such dopants and their use for optical or electro-optical purposes.
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- An improved acid chloride preparation via phase transfer catalysis
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Phase transfer catalysis has been found to be effective for the rapid conversion of carboxylic acids in high yield to the corresponding acid chlorides. The procedure is well suited for acids that exhibit low solubilities in normal organic solvents.
- Burdett
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p. 441 - 442
(2007/10/02)
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- Molecular recognition in the solid state: Controlled assembly of hydrogen-bonded molecular sheets
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A novel hydrogen-bonding motif for the control of solid-state structures has been developed. The motif is based on the hydrogen bonding complementarity of carboxylic acids with 2-aminopyridine derivatives. Linking two aminopyridine groups through a rigid aromatic spacer provides a receptor unit that can complex dicarboxylic acids. When there is a good correspondence between the length of the spacer and that of the carboxylic acid, a discrete 1:1 complex is formed. When the dicarboxylic acid is longer than the receptor, an alternating hydrogen-bonded cocrystal occurs with the carboxylates on each diacid binding to different receptors. This motif dominates the cocrystal, forming even when the relative lengths of the diacid and the receptor change. Within the constraints of the alternating ribbon structure, the spatial position of the two components can be varied in a well-defined and predictable manner.
- Garcia-Tellado, Fernando,Geib, Steven J.,Goswami, Shyamaprosad,Hamilton, Andrew D.
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p. 9265 - 9269
(2007/10/02)
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- Intramolecular quenching of excited singlet states by stable nitroxyl radicals
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Absorbance and steady-state and time-resolved fluorescence measurements were employed to examine the mechanism(s) of excited singlet state quenching by nitroxides in a series of nitroxide-fluorophore adducts. This work establishes the following: (1) the absorption and emission energies of the fluorophores are unaffected by the presence of the nitroxide substituent(s), and the residual emission that is observed from the adducts arises from the locally excited singlet of the fluorophore, not from charge recombination; (2) rate constants for intramolecular quenching by the nitroxides (k) are high (108-1010s-1) and decrease significantly with increasing nitroxide to fluorophore distance-however, relatively high rates of quenching (>108 s-1) are observed over distances as great as 12 ?; (3) F?rster energy transfer does not contribute significantly to the quenching due to the low values for the spectral overlap integrals; (4) the kq's do not increase proportionally to the solvent-dependent increases in the Dexter overlap integral, indicating that energy transfer by the Dexter mechanism is not responsible for the quenching; (5) the values of kq show no obvious correlation with the calculated free energies for photoinduced electron transfer, suggesting that this quenching pathway is also unimportant; (6) for hematoporphyrin-nitroxide adducts, which contain a fluorophore whose singlet energy is below that of the first excited state energy of the nitroxide (thus precluding energy transfer), significant rates of quenching are still observed; (7) for compounds with similar nitroxide-fluorophore distance, an approximately linear correlation is observed between the kq's of the paramagnetic compounds and the nonradiative rate constants of the diamagnetic reference compounds, suggesting that the nitroxide moiety catalyses a preexisting nonradiative pathway in the fluorophore. These results indicate that the quenching arises through electron exchange which causes relaxation of the (local) singlet state to the triplet and/or ground state of the fluorophore.
- Green,Simpson,Zhou,Ho,Blough
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p. 7337 - 7346
(2007/10/02)
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- Synthesis and Thermal Transitions of Some Liquid Crystalline Oligomers
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Fourteen aromatic ester oligomers have been synthesised, the majority of which have not been described previously.They can be considered as model compounds for liquid crystalline polyesters, and as such give useful information regarding the relationship between chemical structure and thermal properties.Such oligomers are also potentially important as precursors to liquid crystalline monomers.
- Chan, W.-C.,Mooney, J. A.,Windle, A. H.
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- Naphthylenedi(heteroarenes), III. - Synthesssssis and Spectroscopic Properties of 2,2'-Naphthylenedibenzazoles
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Starting from 2,2'-(1,4-naphthylene)dibenzoxazole, used as fluorescent whitening agent for polyester fibers and plastics, it is systematically investigated how structural modifications affect spectroscopic propertiessuch as absorption, fluorescence, extinction, and quantum yield
- Frischkorn, Hans,Schinzel, Erich
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p. 1129 - 1136
(2007/10/02)
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