Design and Synthesis of a Highly Stable Six-hydrogen-bonded Serfassembly Yellowish Green Electroluminescent Molecular Duplex

This paper describes the design, synthesis and characterization of a hydrogen-bonded molecular duplex with 1,8-naphthalimide fluorescent pendants. The two oligoamide molecular strands, with complementary hydrogen bond sequences of DDADAA and AADADD, can form an ultra stable self-assembly duplex. Its molecular structure was confu-med by ^1H NMR and ESI-MS, and its photoluminescence properties were determined. The resulting duplex exhibited a dramatically enhanced photoluminescence （PL） quantum efficiency of 63.7% compared to the corresponding 1,8-naphthalimide segment （32.4%）, suggesting that the formation of the duplex with larger molecular weight could successfully inhibit the quenching of the fluorescent pendant. This novel duplex is a prospective candidate for new electroluminescent emitter.     

过渡金属离子识别的1，8-萘二甲酰亚氨衍生物作为荧光传感器的研究

Two fluorosensor systems have been designed and synthesized with their photophysical properties and fluorescence responses toward the transition metal ions studied. The fluorosensor was composed of 1,8-naphthalimide and 4-chloro-1,8-naphthalimide as fluorophore respectively, an amino moiety as the receptor and a hydrocarbon chain as the spacer to link the fluorophore and receptor. Fluorescence intensity of these systems is very weak due to the process of the efficient intramolecular photoinduced electron transfer （PET） in the absence of metal ions. Titration of the transition metal ions can switch on the fluorescence immediately. The intensity of released fluorescence is even higher than the expected from the consideration of the PET in these systems. It may be rationalized that the receptor bound to transition metal ions and the solvation of the fluorophore by the water molecules from the hydrated transition metal salts, may significantly cause fluorescence enhancement.     

A Polymeric Iodiplumbate（Ⅱ） Directed by Heterocyclic Monoprotonated Quaternary Ammonium

A new iodiplumbate polymer [（AOD）（Pb216）]n 1 （AOD = O-protonated 4-azonia-7- oxaspiro（4,5） decane quaternary ammonium） was synthesized by self-assembly reaction of AOD-I, Pb（NO3）2 and NaI, and structurally determined. Compound 1 crystallizes in the hexagonal system, space group P3, with a = 18.2704（8）, c = 8.1663（6） A, V= 2360.8（2） A3, Z = 3, De = 2.783 g/cm^3, F（000） = 1686, C8H17I6NOPb2, Mr = 1319.03, μ（MoKa） = 16.562 mm^-1, the final R = 0.0535 and wR = 0.1793 for 4943 observed reflections with I 〉 2σ（I）. In compound 1, three independent （PbEI6）^2-n infinite chains in each unit cell shape the sketch of compound 1 under the template of AOD-H^2＋ cation. Each （PbaI6）^2-n chain generates from the face-sharing of distorted PbI6 octahedra. （PbEI6）^2-n polyanions interact with AOD-H^2＋ cations by electrostatic interaction in the crystal to feature a so-called hybrid structure. Compound 1 was further characterized with IR, elemental analysis, fluorescence spectrum and thermal analysis. Based on the crystal structure data, DFT calculation was carried out to reveal the electronic structure of compound 1.     

Hydrothermal Synthesis,Crystal Structure and Properties of a Novel Polyoxometalate {[Cu~Ⅱ(1,10-phen)]_2[PMo~Ⅵ_(11)Mo~ⅤO_(40)]} [Cu~Ⅰ(C_8N_4H_6)(C_9H_6NO)(H_2O)]

A new pseudo three-dimensional framework structure of the title compound {[CuⅡ(1,10-phen)]2[PMoⅥ11MoⅤO40]}[CuⅠ(C8N4H6)(C9H6NO)(H2O)](1) has been prepared by the hydrothermal method for the first time and characterized by elemental analyses,X-ray single-crystal diffraction and IR spectra.1 consists of two building blocks,one {[CuⅡ(1,10-phen)]2[PMoⅥ11MoⅤO40]} and one [CuⅠ(C8N4H6)(C9H6NO)(H2O)] coordinated group.Singlecrystal X-ray diffraction revealed that 1 crystallizes in the monoclinic system,space group P2/c with a=13.498(4),b=12.890(3),c=21.465(8),β=97.314o,V=3704(2)3,Mr=2693.61,Z=2,Dc=2.415 Mg/m3,μ=2.915 mm-1,F(000)=2562,S=1.009,the final R=0.0583 and wR=0.1406 for 5129 observed reflections with I2σ(I).Furthermore,compound 1 shows strong fluorescent properties in the solid state at room temperature.The electrochemical behavior of 1 has also been studied by cyclic voltammograms.     

A New Terbium（III） Coordination Compound with 2-Thiophenecarboxylic Ligand： Synthesis and Crystal Structure①

A new coordination compound with formula [Tb（2-TC）3（DMF）]n （1, 2-TC = 2-thio- phenecarboxylic ligand and DMF = dimethylformamide） was synthesized by solvothermal method. The structure of compound 1 was determined by single-crystal X-ray diffraction analyses, and characterized by elemental analyses, IR and powder X-ray diffraction. Structure analysis reveals compound 1, exhibiting a one-dimensional chain structure, crystallizes in triclinic space group P21/c, with a = 9.2751（19）, b = 16.490（3）, c = 15.865（5） A, β = 118.98（2）°, V= 2122.7（9）A3, D,. = 1.916 g/cm3, Mr= 612.45 （C18H15NO7S3Tb）, F（000） = 1196,μ（MoKa） = 3.67 mm-1, Z = 4, R = 0.0616 and wR = 0.0962 for 3865 observed reflections （I 〉 2o（I））, and R = 0.1092 for all data. Meanwhile, the photoluminescent properties of compound 1 were also investigated in the solid state at room temperature.     

Synthesis,Structure and Property of a Novel Coordination Polymer [Tb(C_7H_3NO_4)(C_6H_4NO_2)(H_2O)]

A novel terbium(III) coordination polymer [Tb(C7H3NO4)(C6H4NO2)(H2O)] was successfully synthesized hydrothermally and characterized by single-crystal X-ray diffraction. The complex is of monoclinic, space group P21/c with a = 9.2252(11), b = 14.1477(16), c = 10.5134(12) A, β = 95.770(2)°, V = 1365.2(3) A3, Z = 4, Dc = 2.248 g·cm-3, F(000) = 880, the final R = 0.0176 and w R = 0.0411 for 2149 observed reflections with I 2σ(I). The complex is extended into a three-dimensional network structure with 24-atom rings which are composed of Tb, C and O atoms. The complex displays green fluorescence emission in the solid state at room temperature, which corresponds to 5D4 → 7F5 transition of the Tb(III) ion.     

Synthesis and Crystal Structure of [Cu2（DMF）（H2O）（C7H4NO4）2（C7H3NO4）]2·3.5DMF

A new copper（H） complex [Cu2（DMF）（H2O）（C7H4NO4）2（C7H3NO4）]2-3.5DMF has been synthesized and its structure was determined by single-crystal X-ray diffraction. The crystal is of triclinic, space group P1^- with a = 10.722（3）, b = 18.170（4）, c = 20.923（7）A,α = 105.297（9）, β = 101.701（10）, γ = 105.74（1）°, V= 3615（1）A^3, Z = 2, C58.50H64.50Cu4N1l.50O3150, Mr = 1686.90, Dc = 1.550 g/cm^3,μ= 1.255 mm^-1, F（000） = 1728.00, T = 150（2） K, the final R = 0.0640 and wR = 0.173 for 11310 observed reflections with I 〉 2σ（I）. In the crystal, each formular unit consists of two dinuclear copper（H） compounds, between which the O-H…O hydrogen bonds exist. Each Cu^Ⅱ cation is six-coordinated in an octahedral geometry. The intermolecular hydrogenbonding interaction leads to a 3-D framework of the title compound.     

Synthesis,Crystal Structure and Optical Properties of a Cerium（IV） Complex with Chelidamic Acid

A new cerium complex, （C7H8）[Ce（C7H3NO5）2（H2O）3]·2H2O or （C7Hs）[Ce（HChel）2· （H2O）3]·2H2O （1, H3Chel = 4-hydroxypyridine-2,6-dicarboxylic （chelidamic） acid）, has been prepared by the hydrothermal reaction, and its crystal structure was determined based on single-crystal diffraction data. Compound I crystallizes in monoclinic, space group P21/c with a = 12.4267（9）, b = 10.8195（7）, c = 19.5650（13）A, β = 92.898（3）°, V = 2627.2（3） A^3, Dc = 1.733 g/cm^3, Z = 4, Mr = 685.55, μ = 1.809 mm^-1, λ（MoKa） = 0.71073A and F（000） = 1372. The final R = 0.0455 and wR = 0.1984 for 5983 observed reflections with I 〉 2σ（I）, and R = 0.0490 and wR = 0.2053 for all data. Complex 1 contains one cerium ion, two chelidamic acid ligands, three coordinated water molecules, one discrete toluene molecule, and two discrete water molecules. The Ce（IV） ion is nine-coordinate with the coordination polyhedron made up of four oxygen atoms and two nitrogen atoms from two tridentate chelating chelidamic acid ligands, and three coordinated water molecules. A three-dimensional network is formed by the H-bonds. Moreover, optical properties are investigated and the results show that this complex has sharp optical absorption at 221,396 and 571 nm but no marked fluorescent emission.     

Synthesis and Properties of Novel Fluorescence Probe Based on 1,8-Naphthalimide for Detection of Hydrogen Sulfide

Two fluorescence-enhanced probes,4-(2,4-dinitrophenoxy)-N-(2-hydroxyethyl)-1,8-naphthalimide(NTE-1)and 4-(2,4-dinitrophenoxy)-N-[4-(2,4-dinitrophenoxy)phenyl]-1,8-naphthalimide(NTE-2),have been designed and synthesized for detection of H2S.4-Hydroxy-1,8-naphthalimide as fluorophore in combination with 2,4-dinitrophenyl ether as H2S response site constructed the fluorescence probes.The consequences showed that both NTE-1 and NTE-2 displayed large red-shift(excess 100nm)in absorption spectra and more than 30-fold fluorescence enhancement in response to H2S.Moreover,the dual site probe,NTE-2,displayed wider linear range between fluorescence intensity and concentration of H2S(0-40μmol/L)compared with single site probe,which can be applied to quantita-tive detection of high concentration of H2S.The photomduced electron transfer(PET)response mechanism of probe was further studied by analyzing the distributions of molecular orbital.Importantly,the probes have potential practical applications in the detection of H2S.     

Synthesis,Crystal Structure and Fluorescence Property of N-n-butyl-4-[di(bromoethyl)]amino-1,8-naphthalimide

The halogen as a kind of alkylating reagent is used to introduce new group to realize the fluorescence sensors efficient of metal ion detection. The substituent at C-4 position was double bromine, which defined that the halogen as an alkylating reagent should be further researched and detected for Hg2+. Therefore, the N-n-butyl-4-[di(bromoethyl)]amino-1,8-naphthalimide has been synthesized to detect some metal ions. The title compound has been prepared via substitute reaction and was characterized by IR, 1H NMR, 13 C NMR, and MS. It crystallizes in triclinic, space group P1 with a = 9.0071(18), b = 9.804(2), c = 13.073(3) ?, α = 73.17(3), β = 71.73(3), γ = 62.95(3)o, Z = 2, V = 961.5(3) ?3, Dc = 1.666 g/cm3, F(000) = 484, μ(Mo Kα) = 4.232 mm-1, R = 0.0429 and w R = 0.1004. The presence of intermolecular hydrogen bonds as well as π-π stacking interaction led to the stability of the compound. The fluorescence intensity was obviously lower than that of other ions when Hg2+ was added with the concentration of 1 × 10~(-5) mol·L~(-1).     

Synthesis, Crystal Structure and Luminescent Property of a Novel 1-D Cadmium(Ⅱ) Complex: [Cd2(C8H3NO6)2(H2O)4]n·2nH2O

A novel one-dimensional chain-like coordination polymer constructed from 3-nitrobenzene-1,2-dicarboxylic acid, [Cd2(C8H3NO6)2(H2O)4]n·2nH2O, has been synthesized and its structure was determined by X-ray crystallography method. The crystal belongs to monoclinic, space group P21/c with a = 6.1252(8), b = 20.706(3), c = 8.8067(11) (A), β = 95.608(2)°, V= 1111.6(2)(A)3, Mr =751.12, Dc = 2.244 g/cm3, F(000) = 736, μ = 2.011 mm-1, Z = 2, the final R = 0.0262 and wR = 0.0692for 2338 observed reflections with I ＞ 2σ(I). The structure of the title compound presents a 1-D chain-like structure constructed by dimer units, [Cd2(CsH3NO6)2(H2O)4]n, through two carboxylate oxygen atoms. The fluorescence of the tifle compound has been also discussed in this paper.     

Synthesis, Crystal Structure and Luminescent Property of a Novel 1-D Cadmium(II) Complex: [Cd_2(C_8H_3NO_6)_2(H_2O)_4]_n·2nH_2O

A novel one-dimensional chain-like coordination polymer constructed from 3-nitro- benzene-1,2-dicarboxylic acid, [Cd2(C8H3NO6)2(H2O)4]n·2nH2O, has been synthesized and its structure was determined by X-ray crystallography method. The crystal belongs to monoclinic, space group P21/c with a = 6.1252(8), b = 20.706(3), c = 8.8067(11) , β = 95.608(2)°, V = 1111.6(2) 3, Mr = 751.12, Dc = 2.244 g/cm3, F(000) = 736, μ = 2.011 mm-1, Z = 2, the final R = 0.0262 and wR = 0.0692 for 2338 observed reflections with I > 2σ(I). The structure of the title compound presents a 1-D chain-like structure constructed by dimer units, [Cd2(C8H3NO6)2(H2O)4]n, through two carboxylate oxygen atoms. The fluorescence of the title compound has been also discussed in this paper.     

含萘酰亚胺光功能基元的吡唑啉酮席夫碱的合成及其光谱性质

以4-溴-1,8-萘酐为原料,经亚胺化、取代和还原反应合成了中间体N-对氨基苯基-4-哌啶-1,8-萘酰亚胺(4),4与1-苯基-3-甲基-4-苯甲酰基-吡唑啉酮-5缩合得到一种含萘酰亚胺光功能基元的的新型吡唑啉酮席夫碱——1-苯基-3-甲基-4-苯甲酰基-吡唑啉酮-5缩N-对氨基苯基-4-哌啶-1,8-萘酰亚胺(6)。4和6的结构经1H NMR和IR确证。研究了6在不同溶剂中的光谱性质,发现其吸收光谱和荧光光谱随溶剂的极性不同而表现出不同的光谱特性。进一步研究表明6在不同溶剂中可能以不同的互变异构体存在。     

New green fluorescent polymer sensors for metal cations and protons

A new 4-(N-methylpiperazine)-N-allyl-1,8-naphthalimide with intense yellow-green fluorescence has been synthesized. Then it has been copolymerized with styrene and methylmetacrylate. The photophysical characteristics of the fluorescent dye and its copolymers (poly(St-co-NI) and poly(MAA-co-NI)) have been determined viewing their sensor properties for protons and transition metal cations (Cu²⁺, Fe³⁺ and Zn²⁺). Fluorescence enhancement is the photophysical response of the 4-(N-methylpiperazine)-N-allyl-1,8-naphthalimide to the presence of metal cations and protons, while fluorescence quenching is observed for both copolymers.     

Synthesis and fluorescence of N-substituted-1,8-naphthalimides

A number of novel N-substituted-1,8-naphthalimides have been prepared and their fluorescence yields measured in water at pH 7.4. The type of substitutent and the substitution pattern on the naphthalimide nucleus produce markedly different fluorescence yields, (quantum efficiencies, ø varying from ø = 0-0037 for N-(3-N'-morpholino-1-propyl)-4-amino-3-methoxy-1,8-naphthalirnide (7) to ø = 0–77 for N-(3-bromopropyl)-4-acetamido-1,8-naphthalimide (31).     

A highly sensitive naphthalimide-based fluorescent probe for detection of Cu2+ via selective hydrolysis reaction and its application in practical samples

A novel fluorescent probe CN3, containing 1,8-naphthalimide and picolinate units, was synthesized, and its structure was characterized by ¹H nuclear magnetic resonance spectroscopy (H NMR), ¹³C nuclear magnetic resonance spectroscopy (C NMR), and mass spectroscopy techniques. The detection property of CN3 toward copper ions (Cu²⁺) has been investigated in ethanol–HEPES buffer (v/v = 1/1, pH = 7.40) solution by UV–Vis absorption and fluorescence emission spectra. The results showed that CN3 had a highly selective and sensitive fluorescence quenching response to Cu²⁺, which was attributed to the generation of weak fluorescent N-ethyl-4-hydroxyphenyl-1,8- naphthalimide (compound 2) in polar ethanol–HEPES buffer (v/v = 1/1, pH = 7.40) via selective hydrolysis reaction. The detection of CN3 for Cu²⁺ was not influenced in the presence of other competing metal ions, and the limit of detection was as low as 50.0 nM. Therefore, the color of CN3 changed from colorless to yellowish when the Cu²⁺ was added. Furthermore, the fluorescent probe CN3 was utilized to detect Cu²⁺ in real water samples with fine performance.     

4-(氮杂-15-冠-5)-1,8-萘酰亚胺荧光探针的合成及性能研究

N-丁基-4-溴-1,8-萘酰亚胺与二乙醇胺反应, 合成了N-丁基-4-二(2-羟乙基)氨-1,8-萘酰亚胺, 进一步与对甲基苯磺酸二缩三乙二醇双酯反应合成了N-丁基-4-(氮杂-15-冠-5)-1,8-萘酰亚胺. 用NMR, IR, MS等表征了产物结构. 该化合物在二氯甲烷溶液中识别Li^＋和Na^＋, 识别后吸收光谱和荧光光谱蓝移.     

Modular functional integration of a two-input INH logic gate with a fluorophore-spacer-receptor1-spacer-receptor2 conjugate

The synthesis and photophysical characterization of a fluorophore-spacer-receptor 1-spacer-receptor 2 system, which combines the 1,8-naphthalimide fluorophore with amine and urea receptor units, is reported. Photoinduced electron transfer (PET) from the amino group was blocked by protonation, leading to a drastic fluorescence enhancement (ca. 20 times). Interaction of the urea receptor with anions (F (-), AcO (-), H 2PO 4 (-)) via hydrogen bonding or urea NH deprotonation resulted in significant fluorescence quenching of the 1,8-naphthalimide chromophore in an appropriately chosen model compound (ca. 30-45%). In the presence of both chemical input species, protons and anions, the fluorescence was also quenched. The binding of the anions by NH (+) ammonium receptor has been assumed. The apparent anion binding constants of the protonated conjugate follow the basicity trend of the anions: AcO (-) approximately F (-) > H 2PO 4 (-). The investigated system constitutes an example for the flexible and modular realization of functionally integrated INH logic at the molecular level, using protons and anions as chemical input species and the fluorescence of a PET-active signaling unit as output.     

Structural organization of a {ruthenium[tris(bipyridyl)]} complex by strong π–π stacking of a tethered 1,8-naphthalimide synthon: Impact on electrochemical and spectral properties

The new ligand N-(5-methyl-2,2′-bipyridyl)-1,8-naphthalimide has been prepared by the reaction of 1,8-naphthalimide, 5-(bromomethyl)-2,2′-bipyridine and potassium carbonate in refluxing acetone. Reaction of this ligand and bis(bipyridyl)ruthenium(II) dichloride in refluxing ethanol followed by anion exchange with ammonium hexafluorophosphate produces {ruthenium[bis(bipyridyl)][N-(5-methyl-2,2′-bipyridyl)-1,8-naphthalimide]}(PF₆)₂ (1). In both the solid state (X-ray analysis) and in solution (shown by PGSE-NMR analysis), the 1,8-naphthalimide synthon organizes the cationic metal units into dimers with a strong, directionally oriented (head to tail) π–π stacking interaction. UV–VIS, fluorescence spectroscopy and electrochemical studies indicate that even with the strong interactions of the 1,8-naphthalimide groups, it does not have a significant influence on the properties of the [Ru(bipy)₃]²⁺ core.     

Synthesis and Crystal Structure of N-Hydroxy-9-(3'',4''-methylene-dioxyphenyl)-1,8-dioxo-1,2,3,4,5,6,7,8,9,10-decahydroacridine in Aqueous Media

The title compound N-hydroxy-9-(3',4'-methylenedioxyphenyl)-1,8-dioxo-1 ,2,3,4,5,6,7,8,9,10-decahydroacridine (C20H19NO5, Mr = 353.36) is of orthorhombic, space group Pna21 with a = 14.6914(16), b = 8.8103(10), c = 12.6648(14) (A), Z = 4, V = 1639.3(3) (A)3, Dc = 1.432 g/cm3,μt(MoKα) = 0.103 mm-1, F(000) = 744, R = 0.0445 and wR = 0.1043 for 2172 observed reflections (I ＞ 2σ(Ⅰ)). X-ray analysis reveals that the pyridine and cyclohexane rings adopt boat and half-chair in the title molecule.