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A copper‐catalyzed [3+2] annulation reaction of exocyclic enamines/enol ethers with 1,4‐benzoquinone esters has been developed, providing facile access to N,O‐spiroketals and spiroketals under mild conditions with broad substrate scope (26 examples, 71–94 % yields). Gram scale synthesis and chemical transformations demonstrated that this method is potentially useful in the synthesis of natural products and drugs containing a N,O‐ spiroketal moiety. The chiral N,O‐spiroketal could be obtained with 98 % ee after recrystallization, when a chiral SaBOX ligand was employed. [ABSTRACT FROM AUTHOR]

Photoelectrochemical (PEC) organic conversion is a promising approach to convert low‐cost organics to value‐added chemicals, which urgently needs the development of efficient and highly selective photoanodes. Here, a Pt single‐atom dispersed WO3 amorphous/crystalline homojunction for anodic glycerol oxidation reaction (GOR) coupled with cathodic hydrogen generation is reported. In the coupled photoelectrocatalytic system, the novel Pt‐SA/WOx photoanode reaches a photocurrent density of 2.85 mA cm−2 at 1.2 V versus RHE, with up to 297.3 mmol m−2 h−1 of glycerol conversion rate and 60.2% of dihydroxyacetone (DHA) selectivity, realizing green synthesis of high‐value chemicals. The experimental data and theoretical calculations reveal the regulated band structure, build‐in electric field, and surface charge density of Pt‐SA/WOx, which can improve the carrier lifetime, accelerate charge transfer, and reduce the energy barrier for the GOR process, thus boosting PEC activity and DHA selectivity. This work provides a feasible plan for designing atomic‐level engineering and constructing amorphous/crystalline homojunction on photoanodes for efficient PEC high‐value products from biomass. [ABSTRACT FROM AUTHOR]

Using cinchonine as a raw material, a cinchonine-based isonitrile monomer was prepared after multistep transformation, and finally cinchonine-based catalyst was prepared by polymerization initiated by 4-methoxyphenylethynyl(chloro)bis(triethylphosphine)palladium(II). The new catalyst was used to catalyze asymmetric aldol reactions between cyclohexanone and aromatic aldehydes with different substituent groups. The reaction of cyclohexanone and 3-nitrobenzaldehyde in methanol afforded an enantiomeric excess (ee) value of up to 55% and a diastereomeric ratio (dr) of up to 30:70, indicating high performance of the catalyst. The synthesized compounds were characterized by HPLC, IR, and 1H NMR. [ABSTRACT FROM AUTHOR]

A novel metal–organic framework, ZJU-196, with extraordinary acid–base resistant stability has been successfully synthesized, exhibiting highly efficient separation of acetylene from C2H2/CO2 mixtures under ambient conditions. [ABSTRACT FROM AUTHOR]

A base-mediated bifunctionalization of alkenes for the synthesis of α-sulfonylethanone oximes was developed in water under metal-free conditions. This reaction features a wide substrate scope and facile starting materials to afford the desired products in high yields. [ABSTRACT FROM AUTHOR]

We have successfully designed and synthesized a new tetracarboxylic linker, which constructed its first three-dimensional microporous metal-organic framework ( MOF), [Cu2( DDPD)( H2O)2]•G x ( ZJU -13, H4DDPD=5,5'-(2,6-dihydroxynaphthalene-1,5-diyl)diisophthalic acid, ZJU=Zhejiang University, G = guest molecules) via solvothermal reaction. Due to open Cu2+ sites and optimized pore size, the activated ZJU -13a displays high separation selectivity for C2H2/ CH4 of 74 and C2H2/ CO2 of 12.5 at low pressure by using Ideal Adsorbed Solution Theory ( IAST) simulation at room temperature. [ABSTRACT FROM AUTHOR]

By using different N-donor organic species as additional auxiliary ligands with structure-directing roles, four three-dimensional (3D) calcium-based coordination complexes, [Ca(dbt)(H2O)]n1, [Ca(H-dbt)2(5,5′-dmbpy)2]n2, (4,4′-bpy)0.5[Ca(dbt)(H2O)2]n3, and (H2-dib)[Ca3(dbt)4(H2O)4·2H2O]n4 (H2-dbt = 2,5-dibromoterephthalic acid, 2,2′-bpy = 2,2′-bipyridine, 5,5′-dmbpy = 5,5′-dimethyl-2,2′-bipyridine, 4,4′-bpy = 4,4′-bipyridine, dib = 1,4-di(1H-imidazol-1-yl)benzene), have been successfully synthesized under similar solvothermal conditions and structurally characterized. The organic amine molecules play different roles in the formation of four different metal–organic skeletons with diverse structural topologies, in which complexes 1–3 are neutral, and 4 comprises a negatively charged framework with diprotonated dib as the counterion. Complex 1 features a 3D (6,6)-connected framework structure composed of edge-sharing 1D Ca–O–Ca inorganic chains and dbt ligands. The 2,2′-bpy molecule plays an important role in the synthesis of 1 as the structure-directing agent (SDA). Complex 2 shows a 3D 2-fold interpenetrated diamondoid framework (dia, 66) formed by single metal nodes via linear H-dbt anions and bidentate chelating 5,5′-dmbpy ligands, while complex 3 exhibits a 3D noninterpenetrated pcu network with {412·63} topology constructed from binuclear [Ca2(CO2)4] secondary building units and two types of dbt ligands, in which 4,4′-bpy molecules are ordered within the 3D neutral calcium-based framework as template and space filling agents. Complex 4 is a unique (4,4,4,4,5)-connected 5-nodal topology net, in which the diprotonated dib molecules provide space filling to balance the negatively charged framework. In addition, the thermal stability and the fluorescence properties of complexes 1–4 have been investigated. [ABSTRACT FROM AUTHOR]

The Pd(TFA)2-catalyzed [4+1] annulation of chained or cyclic α-alkenyl-dicarbonyl compounds and unprotected primary amines for "one-pot" synthesis of pyrroles is reported here. Enamination and amino-alkene were involved in this practical and efficient tandem reaction. The annulation products were isolated in moderate to excellent yields with O2 as the terminal oxidant under mild conditions. In addition, this method was applied to synthesize highly regioselective aminomethylated and di(1H-pyrrol-3-yl)methane products. [ABSTRACT FROM AUTHOR]

From two series of Schiff base ligands, ( E)- N-(pyridine-2-yl)(CMe=NPhR) and ( E)- N-(pyridine-2-yl)(CH=NPhR) [R = H, L1a, L1b; 2-CH3, L2a, L2b; 4-CH3, L3a, L3b; 2,6-(CH3)2, L4a, L4b; 2,6-(C2H5)2, L5a, L5b; 2,6-( i-C3H7)2, L6a, L6b; 2,4,6-(CH3)3, L7a, L7b], fourteen mercury(II) complexes, namely, Hg 1a-Hg 7a and Hg 1b-Hg 7b were synthesized. Their structures were established by single-crystal X-ray diffraction, and they were physically characterized by 1H and 13C NMR spectroscopy, ESI-MS, FTIR spectroscopy, elemental analysis (EA), and powder XRD (PXRD). The crystal structures indicate that the position and type of substituent can directly influence the formation of 1D → 3D supramolecular metal-organic frameworks through C-H ···Cl and π-π interactions. Complexes Hg 1a-Hg 7a and Hg 1b-Hg 7b display deep blue emissions at λ = 401-428 nm in acetonitrile solution and light blue emissions at λ = 443-494 nm in the solid state. It is worth noting that Hg 1a, Hg 3a, Hg 1b, and Hg 3b exhibit good aggregation-induced emission (AIE) properties in CH3CN/H2O solutions. [ABSTRACT FROM AUTHOR]

A catalyst-free thiolation of indoles with sulfonyl hydrazides was efficiently developed in water under mild conditions without any ligand or additive. The reaction provided a variety of 3-sulfenylindoles with good to excellent yields and the only by-products were nitrogen and water. [ABSTRACT FROM AUTHOR]

An efficient one-pot method for the syntheses of di- and polybrominated esters from readily available aldehydes is reported. The direct use of the in situ generated byproduct PPh3O in the following reactions greatly improves the efficiency of the cascade. Also, the substrate scope of the reaction is proved to be broad. [ABSTRACT FROM AUTHOR]

The first enantioselective total synthesis of (−)-aspidophylline A, including assignment of its absolute configuration has been accomplished. A key element of the synthesis is a highly enantioselective indole allylic alkylation/iminium cyclization cascade which was developed by employing a combination of Lewis acid activation and an iridium/ligand catalyst. This strategy relies on the direct use of 2,3-disubstituted indoles with secondary allylic alcohols appended at C2 and heteronucleophiles appended at C3, indoles which are easily prepared from simple starting materials under C−H activation conditions. [ABSTRACT FROM AUTHOR]

With graphene oxide, zinc sulfate, sodium thiosulfate and thioglycerol (TG) as starting materials, reduced graphene oxide/zinc sulfide nanocomposite (rGO/ZnS) was successively synthesized with a facile one step method under ambient conditions. Thiosulfate was not only the sulfur source for the synthesis of ZnS but also the reducing agent for the reduction of graphene oxide (GO). TG was used not only as the catalyst for the hydrolysis of thiosulfate but also the catalyst for the reduction of graphene oxide (GO). Hexadecyl trimethyl ammonium bromide (CTAB) functionalized rGO/ZnS (CTAB/rGO/ZnS) was used as a novel electrode modifier for the simultaneous determination of dopamine (DA), ascorbic acid (AA) and uric acid (UA). The combination of reduced graphene oxide (rGO) and ZnS nanoparticles endows the biosensor with large surface area, good biological compatibility, electricity and stability, high selectivity and sensitivity. In the threefold co-existence system, the linear calibration plots for AA, DA and UA were obtained over the range of 50.0–1000 μM, 1.0–500 μM and 1.0–500 μM with detection limits of 30 μM, 0.5 μM and 0.4 μM, respectively. In addition, the biosensor was applied to the determination of AA, DA and UA in urine samples by using standard addition method with satisfactory results. [ABSTRACT FROM AUTHOR]

Two metal-organic frameworks, [Co2(ABTC)(bimh) (OH)]·2H2O (1) and [Co3(ABTC)2(dimb)4]n (2) [H3ABTC = 3,4',5- azobenzenetricarboxylic acid, bimh = 1,1'-(1,4-hexanediy)bis(imidazole), dimb = 1,4-bis(1H-imidazol-1-yl)benzene], were prepared under solvothermal conditions and structurally characterized. Complex 1 demonstrates a complicated 3D (3,8)-connected tfz-d net with (43)2(46.617.85) topology. The framework of 2 can be classified as a rare 3D (3,6,6)-connected net with the Schäfli symbol of (4.62)2(42.610.83)(44.610.8), and exhibits an intriguing self-penetrating motif. Meanwhile, the thermal stabilities and magnetic properties for 1 and 2 were also probed. [ABSTRACT FROM AUTHOR]

Eight silver(I) coordination polymers were synthesized and structurally characterized. Direct reaction of various Ag(I) starting materials with a positively charged and flexible ligand, 1,3-di(2-picolyl)imidazolium ( L ) in different salts, including L -Cl, L -ClO 4 and L -PF 6 , gave compounds [Ag L (NO 3 ) 2 ] ( 1 ), [Ag L (CH 3 CN)](BF 4 ) 2 ( 2 ), [Ag 2 L 2 (NO 3 ) 2 ](NO 3 )Cl ( 3 ), [Ag L (CH 3 CN)](PF 6 ) 2 ·0.5CH 3 CN ( 4 ), [Ag L (NO 3 )](PF 6 ) ( 5 ), [Ag L ](NO 3 )(PF 6 ) ( 6 ), [Ag L (CH 3 CN) 2 ](ClO 4 )(PF 6 )·CH 3 CN ( 7 ), and [Ag L ](ClO 4 ) 2 ·CH 3 CN ( 8 ). Structural analysis revealed that ligand L has three kinds of conformations in these structures. As benefited by the flexible feature of L , the silver chains in 1 – 8 are different and are depended on the shape and the size of counter anions. Anion exchange studies showed that crystals of 4 , 6 and 8 had anion exchange properties, and the channel size in the corresponding solid state structures played a crucial role. These results highlighted the significance of positively charged and flexible ligand L in the construction of various silver chain structures with different conformations and thus packing diagrams for anion exchange studies. [ABSTRACT FROM AUTHOR]

A water soluble lanthanide Tb(III) complex Tb 2 (C 6 NO 2 H 4 ) 6 (H 2 O) 4 has been synthesized as luminescent material, and it is characterized by X-ray crystallography, infrared spectra and elemental analysis, respectively. This material showed excellent characterize of electrochemiluminescence (ECL) in the presence of co-reactant potassium peroxodisulfate (K 2 S 2 O 8 ) at glassy carbon electrode. With the increase of the concentration for nicotinic acid (NA), the ECL intensity of the complex/K 2 S 2 O 8 system in HAc–NaAc buffer solution will be decreased apparently. Novel approach for the detection of nicotinic acid (NA) was developed based on the quenching effect of NA. Furthermore, the possible mechanisms for the ECL behavior of Tb 2 (C 6 NO 2 H 4 ) 6 (H 2 O) 4 /K 2 S 2 O 8 system are proposed. The effects of K 2 S 2 O 8 concentration, pH of the buffer on the ECL intensity have also been discussed in detail. The experiment results showed that the limit of detection for NA was 6.0×10 −7 M ( S / N =3) with a linear range of 2.0×10 −6 –2.0×10 −4 M. [ABSTRACT FROM AUTHOR]

Nocardiopsis alba is frequently isolated from environment and has recently been suggested as a casual symbiotic actinobacterium of diverse invertebrates. Using activity-guided fractionation, we purified two antibacterial cyclic dipeptides, cyclo(ΔPhe-ΔLeu) (albonoursin) and cyclo(ΔmTyr-ΔLeu), from a culture of Nocardiopsis alba ATCC BAA-2165. Analysis of N. alba genome revealed genetic information similar to albonoursin biosynthetic gene cluster, albABC. An albABC gene deletion mutant of N. alba was generated. Liquid chromatography-mass spectrometry analysis showed that the mutant could not produce the cyclic dipeptides. Cyclic dipeptide production in the mutant was restored by genetic complementation with the albABC cloned in a native plasmid of Nocardiopsis. β-Glucuronidase reporter assays with a second mutant construct, in which albABC promoter is transcriptionally fused to the reporting gene gusA, indicated that albABC gene expression was subject to osmoregulation. The system presented will be used to study the metabolic and genetic control of cyclic dipeptide biosynthesis in Nocardiopsis. [ABSTRACT FROM AUTHOR]

An N-heterocycliccarbene-catalyzed stereoselectiveMichael–Mannich–lactamization cascade reaction of tosyl-protected o-amino aromatic aldimines and 2-bromoenals for the constructionof functionalized pyrrolo[3,2-c]quinolines with threeconsecutive stereocenters was achieved in good yields with excellentdiastereo- and enantioselectivities. [ABSTRACT FROM AUTHOR]

A new fluorescence probe for distinguishing Zn2+ and Cd2+ is designed and synthesized. For the first time to our knowledge, this probe can recognize similar metal ions by coherently utilizing intramolecular charge transfer (ICT) and different electronic affinities of various metal ions, instead of by selective coordination alone, which may be interfered with and lose its selectivity easily in a complicated environment, providing a distinct recognition even by the naked eye for Zn2+ and Cd2+ with the sensitivity at the ppb level. This design strategy may initiate a straightforward approach for the selective detection of various metal ions with similar chemical properties in extensive applications such as environmental, industrial, and bio-science. [ABSTRACT FROM AUTHOR]

Highlights: [•] Two dithieno[2,3-b;7,6-b]carbazole-based polymers (P1 and P2) were synthesized. [•] P1 showed a larger band gap (2.07eV) and a slightly deeper HOMO level (−5.2eV). [•] The P1-based photovoltaic devices showed a power conversion efficiency up to 2.51%. [•] P1 has a less curved backbone and a higher absorbance in the visible range. [Copyright &y& Elsevier]

A blue-green-emitting three-dimensional supramolecular compound (C10O2N2H8)(C9O7H6) (1) was synthesised under hydrothermal conditions and structurally characterised by elemental analysis, IR spectrum,1H NMR and single-crystal X-ray diffraction. The crystal belongs to triclinic system with P 1¯ space group. The crystal structure is stabilised by O–H…O, O–H…N hydrogen bonds and π–π interactions (π–π stacking distance is 3.282 Å). Compound1exhibits intense green luminescence in solid state at 298 K (λem = 546 nm). In addition, absorption and fluorescence characteristics of compound1have been investigated in different solvents (DMSO, CH3CN and CH3OH). The results show that compound1exhibits a large red shift in both absorption and emission spectra as solvent polarity increases (polarity: DMSO>CH3CN>CH3OH), indicating a change in dipole moment of compound1upon excitation. Although the emission spectra of compound1in CH3OH are close to it in dimethyl sulfoxide (DMSO), it is revealed that the luminescence behaviour of compound1depends not only on the polarity of environment but also on the hydrogen bonding properties of the solvent. Meanwhile, temperature strongly affects the emission spectra of compound1. Emission peaks of compound1were blue shift at 77 K than those at 298 K in both solid state (ca. 142 nm) and solution (ca. 6–23 nm), which was due to the non-radiative transition decreases at low temperature. Moreover, the quantum yield and fluorescence lifetime of compound1were also measured, which increased with increasing polarity of solvent, lifetime in DMSO at 298 K (τ1 = 0.92 μs, τ2 = 8.71 μs) was the longest one in solvents (298 K: τ1 = 0.87–0.92 μs, τ2 = 7.50–8.71 μs; 77 K: τ1 = 0.72–0.90 μs, τ2 = 6.88–7.45 μs), which was also shorter than that in solid state (298 K: τ1 = 1.13 μs, τ2 = 7.50 μs; 77 K: τ1 = 0.97 μs, τ2 = 8.97 μs). This was probably because of the weak polarity environment of compound1in solid state. [ABSTRACT FROM PUBLISHER]

Abstract: In this research, a simple and facile approach was reported for the synthesis of highly oriented TiO x /N y nanowire arrays that originated from TiO2 nanoparticles. The results indicated that nanowire arrays were fabricated with controllable lengths by adjusting the amount of NH3 under medium pressures. The preferable orientation of nanowires was (103) crystal facet, which led to remarkable V oc values in comparison with TiO2 nanoparticles. An NH3-assisted vapor–liquid–solid (VLS) growth mechanism was proposed for the direct growth of nanowire arrays from TiO2 nanoparticles. [Copyright &y& Elsevier]

A novel unexpected 1D coordination polymer Nd(Nphgly)(1,2-BDC)(H2O)·2H2O (1) containing simultaneously N-phthaloylglycine (Nphgly) and benzene-1,2-dicarboxylic acid (1,2-BDC) ligands has been prepared under the solvothermal conditions. In situ solvothermal aminolysis reaction occurred at benzene-1,2-dicarboxylic acid and glycine when they reacted with neodymium salts. Furthermore, the magnetic and luminescent properties of 1 were studied. [ABSTRACT FROM AUTHOR]

The reactions of diphosphine ligands and isoquinoline (i-C 9 H 7 N) with Ag salts in the mixed solvent of methanol (MeOH) and dichloromethane (CH 2 Cl 2 ) generate the complexes [Ag 2 (dppm) 2 (NO 2 ) 2 ]·(i-C 9 H 7 N) 2 ( 1 ), [Ag 2 (dppm) 2 (i-C 9 H 7 N) 2 (BF 4 )](BF 4 ) ( 2 ), {[Ag(dppe)(i-C 9 H 7 N) 2 ](CF 3 SO 3 )·(i-C 9 H 7 N)} n ( 3 ), {[Ag(dppb)(i-C 9 H 7 N) 2 ](BF 4 ) 2 ·(i-C 9 H 7 N) 0.5 } n ( 4 ) and {[Ag(dppb)(i-C 9 H 7 N)(CF 3 SO 3 )]·(i-C 9 H 7 N)} n ( 5 ). These complexes were all characterized by IR, elemental analysis, X-ray diffraction, luminescence, 31 P and 1 H NMR spectroscopy. Complexes 1 and 2 have dinuclear structures, while complexes 3 , 4 and 5 have 1D infinite zigzag chain structures. Complexes 1 and 2 are metal clusters in which there exist Ag⋯Ag metal bonds, whilst in compounds 3 , 4 and 5 , two silver atoms are bridged by the diphosphine ligands to form the 1D infinite zigzag chains. Complexes 3 and 5 are 2D topologically promising architectures and complex 4 is a 3D topologically promising architecture. In addition, complexes 1 – 5 exhibit interesting fluorescence in the solid state at room temperature. At the same time, we also studied the terahertz spectra of the complexes, which show more accurate characteristics of each group of complex. [ABSTRACT FROM AUTHOR]

A new protocol for generating indoleazepine 9 via an Ir-catalyzed intramolecularly asymmetric amination of secondary allylic alcohol 5 in the presence of Carreira ligand ( 10 ) and Sc(OTf) 3 is described. This methodology has been exploited in the facile synthesis of natural (−)-aurantioclavine ( 1 ), a biosynthetical precursor of communesins, and its unnatural enantiomer (+)-aurantioclavine ( ent - 1 ). [ABSTRACT FROM AUTHOR]

In order to develop more stable packing materials for high-temperature liquid chromatography (HTLC), a new stationary phase, 1-naphthyl attached poly(2-hydroxyethylmethacrylate- N -methacryloyl-(L)-histidine-methyl-ester) (NA-PHEMAH) polymer was synthesized in this work. The NA-PHEMAH polymer particles with 2.0–2.1 μm in diameter were then evaluated for use as a stationary phase in high-temperature liquid chromatography. Separation of vanillin, ethyl vanillin, coumarin, 6-methylcoumarin, and 7-methylcoumarin was achieved on this NA-PHEMAH column using HTLC at 125–200 °C with 2% or 5% methanol in the mobile phase. Successful separation of the test analytes was also obtained using subcritical water chromatography (SBWC) at 200 °C. Evaluation of the long-term stability of the NA-PHEMAH stationary phase revealed that the column was stable for over 500 h at 150 °C. These results demonstrate that the new NA-PHEMAH stationary phase is suitable for high-temperature liquid chromatography separations due to its excellent stability at high temperatures. [ABSTRACT FROM AUTHOR]

In this study, a highly efficient photocatalyst, NH 2 -MIL-125(Ti)/g-C 3 N 4 /NiPd (NH 2 -MIL-125(Ti)/CN/NiPd), was successfully synthesized for photocatalytic water reduction to produce H 2 . Under visible-light irradiation, the prepared NH 2 -MIL-125(Ti)/CN/NiPd composite clearly showed enhanced photocatalytic performance for H 2 evolution compared to NH 2 -MIL-125(Ti), NH 2 -MIL-125(Ti)/CN, and NH 2 -MIL-125(Ti)/NiPd. The as-synthesized NH 2 -MIL-125(Ti)/0.75CN/Ni 15.8 Pd 2.1 photocatalyst exhibited a high H 2 production rate of 8.7 mmol g −1 h −1 , 322 and 1.3 times higher than those of NH 2 -MIL-125(Ti)/0.75CN and NH 2 -MIL-125(Ti)/Ni 15.8 Pd 4.1 , respectively. The enhanced photocatalytic performance can be attributed to the intimate interfacial contact between NH 2 -MIL-125(Ti) and CN, accelerating the charge transfer, as well as loaded NiPd nanoparticles, increasing the light-absorbing capacity and accelerating the charge transfer of NH 2 -MIL-125(Ti)/CN. This work demonstrates that the addition of appropriate co-catalysts onto MOF/CN hybrid with intimate contact interface provides a new approach to design highly efficient and solar-energy-harvesting photocatalysts. [ABSTRACT FROM AUTHOR]

Five mono-nuclear silver (I) complexes with 6,7-dicyanodipyridoquinoxaline ligand, namely {[Ag(DPEphos)(dicnq)]NO3}2. CH3OH (1), [Ag(DPEphos)(dicnq)]BF4.CH3OH (2), [Ag(XANTphos) (dicnq)]CF3SO3 (3), {[Ag(XANTphos)(dicnq)]NO3}2 (4) and [Ag(XANTphos)(dicnq)]ClO4.CH2Cl2 (5) {DPEphos = bis[2-(diphenylphosphanyl) phenyl]ether, dicnq = 6,7-dicyanodipyridoquinoxaline, XANTphos = 9,9-dimethyl-4,5-bis(diphenylphosphanyl)xanthene} were characterized by X-ray diffraction, IR, 1H NMR, 31P NMR, fluorescence spectra and terahertz time-domain spectra (THz-TDS). In the five complexes the AgI, which is coordinated by two kinds of chelating ligands, adopts four-coordinate modes to generate mono-nuclear structures. The C-H...π interactions lead to formation of a 1D infinite chain for complexes 2 and 3. The crystal packing of complexes 1 and 5 reveal that they form 3D supermolecular network by several pairs of C-H...π interactions. The emissions of these complexes are attributed to ligands-centered [π-π8 ] transition based on both of the P-donor and N-donor ligands. [ABSTRACT FROM AUTHOR]

The protocol works in the absence of a ligand and can be applied to a series of anilines and cyclohexanones. [ABSTRACT FROM AUTHOR]

The article presents chemical equations for the article "Gold Nanoparticles Supported on Titanium Dioxide: An Efficient Catalyst for Highly Selective Synthesis of Benzoxazoles and Benzimidazoles" by L. Tang and colleagues published in the periodical "Chemical Communications" in 2014.

Abstract: A fluorescent chemosensor, ortho-methylated boron-dipyrromethene (o-MBDP) has been synthesized and characterized. It featured excellent selectivity and sensitivity for Ag+ and Hg2+ ions, which could enhance the weak fluorescence of o-MBDP drastically by several hundred times through coordination and as a result, behave as an efficient “turn-on” fluorescent probe. The detection upper limit for Ag+ ion could be decreased by at least one order of magnitude with the introduction of the ortho-methyl group, in comparison with analogous boron-dipyrromethene (BDP) sensors, indicating the feasibility in extensive application areas as chemosensors. [Copyright &y& Elsevier]

Abstract: Two new chromophores, CLDS1 and CLDS2, based on a similar D–π–A structure as the phenyltetraene chromophore CLD, but with an alkylthio group perpendicular to the direction of the long molecular axis as isolation spacer were synthesized. Through a urethane forming reaction between 3-isocyanatopropyltriethoxysilane (ICTES) and chromophores, the alkoxysilane dyes were synthesized. Subsequently, a series of transparent and homogeneous inorganic-organic hybrid films were prepared via a sol–gel process of the alkoxysilane dye with triethoxyvinylsilane. The molecular structures of the resultants were confirmed by 1H NMR, FTIR and UV–visible spectra. After electric poling, the nonlinear optical coefficients (d 33) of the hybrid films F-CLDS1 and F-CLDS2 were determined to be 104.54 and 98.17 pm V−1, respectively, which are almost 3 times the d 33 value of hybrid film containing CLD (37.78 pm V−1), indicating that the incorporation of alkylthio group can efficiently improve the macroscopic optical nonlinearities of hybrid materials. [Copyright &y& Elsevier]

The present study reported here synthesisof three novel two-dimensional(2D) polythiophene derivatives with conjugated terthiophene–vinyleneside chainpoly{3-(5″-hexyl-2,2′:5′,2″-terthiophenyl-5-vinyl)thiophene-alt-thiophene}(P1), poly{3-(5,5″-dihexyl-2,2′:5′,2″-terthiophenyl-3′-vinyl)thiophene-alt-thiophene}(P2), and poly{3-(4,4″-dihexyl-2,2:5′,2″-terthiophene-3′-vinyl)thiophene-alt-thiophene}(P3)thatwere synthesized via stille coupling reaction. The terthiophene sidechain with different conformations conjugated to the polythiophenemain chain via vinyl linkage provided the ability to control the molecularorganization, hence affecting the optoelectronic and electrochemicalproperties of 2D polymers. TD-DFT calculation with the B3LYP/6-31+g(d)function on electronic structures of the monomers was consistent withthe experimental results. It suggested that the energetic states ofHOMO and LUMO were highly dependent on the side-chain architectures.These polythiophene thin films fabricated by spin-casting show a broaderabsorption ranges from 300 to 700 nm which was significantly widerthan the absorption of pure poly(3-hexylthiophene). When comparingthe solid-state absorption spectra of these polymers before and afterthermal annealing, P3displayed the most red-shift inthe wavelength range between 450 and 700 nm. It was presumably dueto an extended conjugation length resulting from the linear conformationand preferred chain packing, as manifested in the X-ray diffraction.Molecular dynamics (MD) simulation on polymers with different sidechains in isolated and packed states suggests planar conformationof the main chain was adopted and regulated by the side chains whichwere placed in parallel with the main-chain direction. Interestingly, P1solution revealed an excitation-dependent emission property,suggesting a structural inhomogeneity in solution. Contrary to P1, the PL spectra of P2and P3showedonly one emission peak at 460 nm, regardless of the excitation energy.Orientation and regiochemistry of the terthiophene side chain hada major impact on the overall optical and electronic properties ofthe polymer. Moreover, the HOMO and LUMO of these three polymers hadbeen determined through cyclic voltammetry. HOMO of the three polymerswere in the following order: P1> P2> P3. It implied that the energy level was regiochemistry dependentand directly associated with the linked position between backboneand conjugated side chain. Most importantly, through mesogen-jacketed-likedesign strategy employed in the present study, the improved packingof these two-dimensional polymers offered insights into structuredesign to enhance properties that have strong ties to the electronicdevices. [ABSTRACT FROM AUTHOR]

Abstract: In this work, a T-shape organic molecule 5-(pyridin-4-yl)isophthalic acid was synthesized via a Suzuki coupling reaction and used as the ligand for a serial of mixed-lanthanide complexes. The chemical compositions of the lanthanide complexes were determined as (Eu x Tb1− x )2L3(H2O)4 by elemental analysis (EA) and thermo gravimetric analysis (TGA). The luminescent properties of the as-synthesized complexes were investigated and the intramolecular energy transfer mechanisms involved, were discussed. Efficient energy transfer from Tb3+ to Eu3+ was observed and controlled by changing the molar ratio of Tb3+ to Eu3+ ions, allowing the color tuning on the luminescent emission of the mixed-lanthanide complexes. [Copyright &y& Elsevier]

Abstract: A series of novel aryl-2H-pyrazole derivatives bearing 1,4-benzodioxan or 1,3-benzodioxole moiety were designed as potential telomerase inhibitors to enhance the ability of aryl-2H-pyrazole derivatives to inhibit telomerase, a target of anticancer. The telomerase inhibition tests showed that compound 16A displayed the most potent inhibitory activity with IC50 value of 0.9μM for telomerase. The antiproliferative tests showed that compound 16A exhibited high activity against human gastric cancer cell SGC-7901 and human melanoma cell B16-F10 with IC50 values of 18.07 and 5.34μM, respectively. Docking simulation showed that compound 16A could bind well with the telomerase active site and act as telomerase inhibitor. 3D-QSAR model was also built to provide more pharmacophore understanding that could be used to design new agents with more potent telomerase inhibitory activity. [Copyright &y& Elsevier]

Abstract: Three series of novel heterocyclic azoles derivatives containing pyrazine (5a–5k, 8a–8k and 11a–11k) have been designed, synthesized, structurally determined, and their biological activities were evaluated as potential telomerase inhibitors. Among the oxadiazole derivatives, compound 5c showed the most potent biological activity against SW1116 cancer cell line (IC50 =2.46μM against SW1116 and IC50 =3.55μM for telomerase). Compound 8h performed the best in the thiadiazole derivatives (IC50 =0.78μM against HEPG2 and IC50 =1.24μM for telomerase), which was comparable to the positive control. While compound 11f showed the most potent biological activity (IC50 =4.12μM against SW1116 and IC50 =15.03μM for telomerase) among the triazole derivatives. Docking simulation by positioning compounds 5c, 8h and 11f into the telomerase structure active site was performed to explore the possible binding model. The results of apoptosis demonstrated that compound 8h possessed good antitumor activity against HEPG2 cancer cell line. Therefore, compound 8h with potent inhibitory activity in tumor growth inhibition may be a potential antitumor agent against HEPG2 cancer cell. Therefore, the introduction of oxadiazole, thiadiazole and triazole structures reinforced the combination of our compounds and the receptor, resulting in progress of bioactivity. [Copyright &y& Elsevier]

Abstract: In this paper, effect of NH4Cl flux concentrations (0, 1, 2, 3 and 4wt%) on the crystal structure, morphology and photoluminescent properties of Sr2SiO4:Eu3+ phosphors synthesized by a microwave sintering at 1200°C for 1h was investigated and discussed. X-ray powder diffraction analysis showed the crystal structure was not affected and the pure Sr2SiO4 phase was formed without second phase or phases of starting materials when adding with the NH4Cl flux. The SEM images indicated that increase of the NH4Cl flux enlarged the particle size of the phosphor particles. The photo-luminescence results showed the addition of 1wt% NH4Cl flux much improved the emission intensity at λ em of 617nm as the excitation spectrum at λ ex of 395nm. The decay times of Sr2SiO4:Eu3+ phosphors with different NH4Cl flux concentrations were obtained around 2.47–2.52ms. [Copyright &y& Elsevier]

An abstract of the article "Copper-Catalyzed Difluoromethylation of Propargylamide-Substituted Indoles: Synthesis of Mono- and Bis-Difluoromethylated Indoloazepinone Derivatives" by Hui-Liang Hui-Liang and colleagues is presented.

An abstract of the article "A Practical Enantioselective Total Synthesis of (-)-(S)-Stepholidine" is presented.

Carbon nanotube/cubic nickel cyanoferrate/polyaniline hybrid films were synthesized by cyclic voltammetric electrodeposition of NiSO4, K3Fe (CN)6 and aniline in a H2SO4/Na2SO4 solution on a platinum electrode coated with carbon nanotubes. The electrocatalytic oxidation performance for ascorbic acid (AA) using the hybrid film as an electrode was investigated by cyclic voltammetry and chronoamperometry. The morphology of the film was investigated by scanning electron microscopy. The hybrid film was used for AA detection, and showed a high electrocatalytic activity, a high sensitivity and a low detection limit. The linear range for the detection of AA was from 1×10−5 to 1.4×10−4 mol/L with a correlation coefficient of 0.9966, a sensitivity of 654mAM−1 cm−2 and a detection limit of 6.09×10−6 mol/L. The diffusion coefficient and the catalytic rate constant of the electrocatalytic oxidation of AA were studied by chronoamperometry. [New Carbon Materials 2013, 28(1): 26–32] [Copyright &y& Elsevier]