Australian Journal of Chemistry

Is formate an energy source? We achieve formate electrooxidation in a practical and convenient way. The precursor of the oxidation is free HCOO^– in fuel liquid rather than Pt-HCOOH. Formate is able to bypass the undesirable poisoning path to alternatively form carbon dioxide.

Homologous series of 4,5-disubstituted 2H-[1,2,3]-triazole derivatives were synthesized from chalcones and sodium azide via CuI-catalyzed oxidative cycloaddition reaction in order to characterize their liquid crystalline properties by polarizing optical microscopy and differential scanning calorimetry.

The recovery of platinum from acidic solutions was examined and consists of two steps. For each reaction within a step, the rate constants were determined. The first two reactions in step 1 were diffusion controlled unlike the third reaction in step 2 step, which took place at the surface of activated carbon. The results were in excellent agreement to the assumed model.

Simultaneous temperature measurement by external and internal sensors revealed hidden inhomogeneities within the reaction mixtures of a debated microwave-assisted benzylation involving a 2-substituted pyridine reagent. Rate enhancement could be explained by macroscopic-scale localized heating in the boundary layers close to the vessel surface.

Two luminescent functionalised supramolecular coordination polymers based on an aromatic carboxylic acid ligand exhibit efficient luminescence sensing for Hg²⁺ ions.

A 3D heterometal–organic framework was synthesised. The compound is 2-fold interpenetrating. It displayed good thermal and solvents stability and exhibited high sensitive and qualitative luminescent detection of nitrobenzene. The present study is the first report on the use of an interpenetrating heterometallic metal–organic framework as a luminescent probe for nitrobenzene

The Ru₂ double bond in (RuPz)₂, composed of one σ bond and one π bond, is unravelled by DFT (B3LYP) and WFT (CASSCF and NEVPT2) calculations. The ground state shows a Ru–Ru distance of 2.38 Å, a stretching frequency of 202 cm^-1, and a bonding energy of 30.7 kcal mol^-1. This agrees with experimental results.

Four dual BODIPY-carbazole conjugates (BDPa–d) with various linkers were synthesized. The results suggest that the linkers have significant effect on the photophysical and electrochemical properties of the conjugates. The conjugates show intensive absorption, remarkable Stocks shifts, and suitable HOMO–LUMO energy levels, which are promising for photovoltaic applications.

Cross-linked poly(acrylamide) microspheres, PAMBA, with mean diameters ranging from 169.7 to 525.2 nm were successfully prepared by dispersion polymerisation of acrylamide in an aqueous ammonium sulfate solution with N,N′-methylenebis(acrylamide) as the cross-linking agent and sodium dodecyl sulfate as the stabiliser. The mean diameter of the PAMBA microspheres can be controlled by adjusting the concentration of the stabiliser.

Lanthanide phosphate nanoparticles were produced under continuous flow in a vortex fluidic device in the presence of polyvinylpyrrolidone. Changes in the morphology of the dandelion-shaped nanoparticles were possible by varying the chain length of PVP, and the rotational speed and tilt angle of the tube in the vortex fluidic device.

Methylene violet 3RAX 1 and its derivatives 2–5 were synthesised and characterised. The binding mode between the synthesised compounds and DNA and their DNA photocleavage ability were investigated. The results suggest that the binding mode between methylene violet 3RAX and DNA, its ability to generate singlet oxygen, and DNA photocleavage activity could be changed through modification of the amino group on methylene violet 3RAX.

The simultaneous α-iodination and N^β-arylation mechanism of 5-alkyoxy-4-phenylamino-2(5H)-furanone by (diacetoxyiodo)benzene was investigated by means of density functional theory (DFT), selecting 4-(diphenylamino)-5-methoxy-3-iodo-2(5H)-furanone as the calculation model.

The determination of enantiomeric purity is frequently required in synthetic chemistry. NMR can be used for this purpose if suitable chiral solvating agents are available. Nine new (+)-dehydroabietylimidazolium salts were synthesised and used as efficient chiral solvating agents for resolving several racemic aromatic and non-aromatic carboxylate salts.

Zeolite X base catalysts containing alkali metal ions are prepared from amorphous bamboo leaf ash. The catalysts are found to be highly active in cyanoethylation of methanol under an instant heating environment that mimics microwave fast heating.

An effective, high-yielding strategy for O-glycosylation is studied and applied in solid-phase synthesis.

Oxidations of W(CO)₄(LL) compounds were investigated electrochemically. The electrogenerated radical cations are unstable toward disproportionation, carbon monoxide substitution, and nucleophilic attack. The kinetics of these reactions were examined using a number of techniques including a.c. voltammetry and chronocoulometry. Infrared spectroelectrochemistry was used to characterize two [W(CO)₄(LL)]⁺ species.

Secondary amines react with maleic anhydride under kinetic control across the C=O functionality exclusively. The product changes into N-substituted maleimic acid under thermodynamic control. The Fukui functions determined at the B3LYP/6-31G* level reveal that the carbon atom of the carbonyl group is the hardest site, thus making it the preferred site for the nucleophilic attack.

A novel alkaloid-like compound containing the azabicyclo[3.3.1]nonane core is reported to be the first instance of using the bridged Ritter reaction with hydrogen cyanide. The structure of this unique and unexpected compound was determined with the aid of X-ray crystallography.

Peptide nanofibres with arginine as a building block have been prepared via a self-assembly method and decorated with Cu and Ni nanoparticles. These prepared nanostructural compounds present a unique catalytic activity for the synthesis of 5-substituted 1H-tetrazoles and the N-arylation of amines.

The hydrogenated derivative of levoglucosenone was functionalised at the α-position with aldol chemistry using a series of aromatic aldehydes. The benzylidene derivative was then hydrogenated stereospecifically and the product transformed using a Baeyer–Villiger reaction into (3R,5S)-3-benzyl-5-(hydroxymethyl)-4,5-dihydrofuran-2(3H)-one, a chiral building block that can be used for the synthesis of the protease inhibitor indinavir.

Electrochemical determination of mass-transport parameters is often subject to small errors, which influence the outcomes of voltammetric experiment–theory comparisons. In particular, a perilous situation emerges when a quasi-reversible model with slightly overestimated mass-transport parameters is used to quantify the electrode kinetics for a system that approaches a reversible limit.

The electropolymerisation of N-ethylanilinium trifluoroacetate, a protic ionic liquid (PIL), was carried out, where the PIL served as the monomer precursor, solvent, and supporting electrolyte for the polymerisation process resulting in different morphologies, a greener approach to production, and a highly processable polymer.

A simple and sensitive fluorescence probe, based on a substituent coumarin as fluorophore and acrylate as recognition site, is able to selectively and quantifiably detect cysteine over other biothiols such as homocysteine and glutathione.

An integrated device is developed that incorporates a sensor, readout system, and battery on paper. The electrochromic readout system allows the pH range of a sample solution to be determined visually rather than using an LCD display or voltmeter. The integrated potentiometric sensor and readout system provides a cost-effective and lightweight solution for pH monitoring.

Aerial oxidation of Cd(TCNQ)₂ during slow recrystallization in tetrahydrofuran produced a dicarboxylate ligand–Cd complex, with the N 1s XPS spectrum showing that this chemical transformation is complete.

A simple and highly sensitive method for the detection of hydrogen peroxide in food samples was developed by electrodepositing Cu and MnO₂ onto a g-C₃N₄ coated glassy carbon electrode. The sensor exhibits high selectivity, good stability, and reproducibility.

Different aminoalcohol ligands (TEA, DEA, and MEA) were found to affect the size and optical properties (band gap and emission peak) of ligand-stabilized ZnO quantum dots. Ligands of higher polarity and larger molar volume produce smaller, more monodisperse ZnO quantum dots. As the size of ZnO quantum dots decrease, the optical properties are blue-shifted.

SnFe₂O₄ has been widely used as a magnetic material or catalyst for the oxidative removal of organic pollutants, but never used as an electrode material in lithium ion batteries. In this study, binder-free SnFe₂O₄-rGO hybrid films with both horizontal and vertical channels were fabricated through electrophoretic deposition to present excellent electrochemical performance of lithium ion batteries.

Heterocycles fused to quinoline frameworks widely occur in many biologically active natural products and in medicinally important drugs. Our strategy represents the first collective synthetic concise and efficient entry to nine novel condensed tetracyclic quinolinones by Friedel–Crafts cycliacylations. The simplicity and wide variability of the procedures highlights the efficiency of the methodology for constructing complex fused-ring systems.

The attempted synthesis of a β-keto imidazolidinone nitroxide by oxidation of the β-hydroxy imidazolidinone precursor led to an unexpected ring-opening reaction. A β-fragmentation mechanism is suggested, rather than a Baeyer–Villiger rearrangement.

A simple procedure for the condensation of the bio-derived furfurals, 5-(methyl)furfural (MF) and 5-(chloromethyl)furfural (CMF), with primary amines is described. The experiments were conducted in both batch and flow conditions, with reaction times as short as 60 s. Mild reaction conditions were necessary for CMF in order to selectively react on the aldehyde and not the methyl-chlorine group.

Orpiment (As₂S₃) quantum dots (QDs) were first synthesised through top-down and bottom-up routes, and exhibit strong blue photoluminescence emission. They were effective against murine melanoma B16 cells through induction of apoptosis. Moreover, self-assemblies of orpiment QDs were fabricated by destroying the protective surface ligand layer surrounding the inner orpiment cores by addition of an acid.

The ability of gold anti-arthritic agents and gold nanoparticles to alter production in RAW264.7 macrophages of a number of cellular mediators of inflammation, including reactive oxygen and nitrogen species, interleukin-10 and tumour necrosis factor, have been compared.

In this research, relatively high surface area mesoporous ZnS nanoparticles have been synthesised using two different media. The mechanism of the by-product assisted synthesis of the prepared mesoporous ZnS nanoparticles in EtOH has been investigated using field emission scanning electron microscopy, transmission electron microscopy, powder X-ray diffraction, diffuse reflectance spectroscopy, N₂ adsorption–desorption, and FT-IR spectroscopy analyses.

A custom-designed liquid–liquid countercurrent chromatographic instrument (above left), based on the J-type centrifuge, in which at least one phase contains an ionic liquid, is capable of the separation of inorganic (above right), organic, or bio-based materials on the 0.1–10 g scale.

A series of all-trans acceptor–π-donor (acceptor) compounds were conveniently synthesised via the three-step synthetic method Arbuzov reaction, solvent-free Horner–Wadsworth–Emmons reaction, and Mizoroki–Heck reaction. They all exhibit obvious solvatochromic effects, strong two-photon excited fluorescence, and large two-photon absorption cross-sections.

A polymer, β-MEA, was synthesised from β-cyclodextrin (β-CD), 3-chloro-2-methylpropene (MAC), epoxysuccinic acid (ESA), and 2-acrylamido-2-methyl propane sulfonic acid (AMPS). Its structure, molecular weight, thermal stability, inhibition performance, and mechanism were investigated. The results showed that β-MEA achieves better scale and corrosion inhibition efficiencies compared with poly(aspartic acid) (PASP).

A novel MoO₂ composite supported on mesoporous graphene oxide (m-MoO₂/GO) is successfully synthesised. The introduction of a mesoporous structure into GO sheets not only promotes the catalytic activity, but also makes m-MoO₂/GO more effective in catalysing olefins with a long carbon chain and large ring size.

A novel series of 3D Ln^III–Cu^I heterometallic coordination polymers {[Ln₂Cu₄I₃(ina)₇(DMA)₂]_n·nDMA were synthesised by a solvothermal reaction, comprising of inorganic Cu₄I₃ clusters linked by Ln₂(ina)₇(DMA) rod units. The luminescent properties of partial compounds have been investigated in detail.

Crystalline neutral red accelerates microbial methane generation from coal. Industrial scale-up requires knowledge of crystalline polymorphs that may behave differently with methanogens. Temperatures in the dark, subterranean environments where methanogenesis occurs range from 50–70°C, conditions where neutral red crystallises or transforms to a new polymorph.

The fluorescence and Raman intensity of poly(3-hexylthiophene) (P3HT)-coated gold nanoparticle arrays with different particle sizes and interparticle distances were enhanced in comparison with pristine P3HT due to electromagnetic field enhancement based on localised surface plasmon resonance (LSPR). The fluorescence and Raman signals of P3HT on gold nanoparticle arrays were gradually enhanced with increasing nanoparticle diameter/interparticle distance ratio.

Bifunctional magnetic–luminescent Fe₃O₄@Y₂O₃:Eu³⁺, Li⁺ composite particles were prepared with Y₂O₃ co-doped with Eu³⁺ and Li⁺ ions as a shell to enhance their luminescence intensity and saturation magnetisation through a urea homogeneous precipitation method.

The present review summarises the latest developments on the ultrasound-assisted synthesis of biologically relevant N-heterocycles at ambient temperature.

The photocatalytic reaction of prepared Bi₂WO₆/g-C₃N₄ composite materials followed a direct solid-state Z-scheme mechanism, which facilitated charge transfer and effectively reduces the recombination of photoinduced electrons and holes, resulting in an enhanced photodegradation efficiency under visible light irradiation.

Unique self-assembled nanoparticles with sea urchin-like pointed edges were synthesized by a solvothermal approach. The high value of the apparent rate constant, k_app, is due to the unique morphology of the Co₃O₄ nanoparticles.

Different adsorbents (Tenax TA, Porapak Q, and Hayesep Q, among others) were evaluated in a headspace dynamic system containing a mixture of insect semiochemicals. The results demonstrated that Porapak Q and Porapak Rxn RP were able to produce similar ratios of compounds to that of a standard solution with the highest recovery yields.

The first azulenyl squaraine dye was reported in 1966, but little activity in the scientific literature has given the impression that they remain unexplored. However, much has been recorded in the patent literature and it is the purpose of this review to bring this record to the attention of researchers.