On treatment with base, the natural pyrethrins pyrethrin I, cinerin I and jasmolin I undergo elimination to transient cyclopentadienones that dimerise to afford regioisomeric endo cycloadducts. (Image credit: J. H. Ryan.)
In the analytical methods for the extraction of rare-earth elements (REEs) by diglycolamide (DGA), liquid–liquid extraction experiments can demonstrate basic extraction properties, spectroscopic techniques can provide information on the inner-sphere coordination of REEIII–DGA complexes, and scattering techniques can be used to study the size and morphology of aggregates with nanoscale structures. (Image credits: bottom right, G. B. Deacon et al.; other images, A. Gong.)
We have developed a facile oxidative cyclization of β-ketothioamides for the simultaneous formation of a compound library similar to natural product benzothiazole derivatives, which are important structural motifs that are prevalent in both natural and designed compounds and display interesting biological and physical properties. (Image credit: M. Cui.)
This paper reviews recent progress in rare-earth perovskite oxide materials, explores the effects of capacity factors, lattice defects, different metal active centers and perovskite modifications on crystal structure and applied properties, discusses the effects of synthesis processes (sol-gel, co-precipitation, microemulsion, hydrothermal, high-temperature) on their physical and chemical properties, and summarizes their applications in pollutant catalytic oxidation and photocatalytic degradation, VOCs gas sensing, and photocatalytic splitting of water for hydrogen production and carbon dioxide reduction and conversion. (Image credit: P. Li.)
DFT calculations and MD simulation were used to analyse the corrosion inhibition activity and mechanism of N,N′-(1,4-phenylene)bis(1,1-di(pyridin-2-yl)methanimine) (PBDPM), and the structure–activity relationship was tested. The results from SEM and water contact angle and potentiodynamic polarisation curve measurements verify the adsorption behaviour of PBDPM on the surface of mild steel, and test that PBDPM plays a role in corrosion inhibition by changing the hydrophilic and hydrophobic properties of the surface of mild steel. (Image credit: Xiaolong Li.)
The doping of WO3 with transition metal elements significantly optimised its photochromic properties. Mo changed the colour after UV irradiation and Cu increased the fading rate of WO3. Photochromic ink and photochromic rewriting paper were prepared using the obtained photochromic powders with a cycle life of more than 50 times. (Image credit: Xuhui Jin.)
A novel Co(OAc)2/NHPI-catalyzed oxidation of 3-arylmethyl sulfonyl imines to prepare 3-arylcarbonyl analogues has been realized. 3-Arylcarbonyl sulfonyl imines were comprehensively synthesized from benzyl substrates for the first time. The reactions proceeded in moderate to excellent yields. Mechanistic investigation suggests that alcohol compounds A are the key intermediates for the formation of products 2. (Image credit: Gan Haifeng.)
The process of engaging chemistry academics across multiple institutions in conversations to establish consensus regarding measuring chemistry threshold learning outcomes (CTLOs) is complex. Brian Yates adopted a unique leadership approach by combining relational, distributed and collaborative leadership in initiating and supporting chemistry academic communities of practice (CoPs). (Image credit: Gwendolyn Lawrie.)
This article is part of the collection: Dedication to Brian Yates.
Four 2-D Ln-CPs [Ln = La (1), Pr (2), Sm (3), Eu (4)] based on mixed ligands, 2-[(4-carboxyphenyl)methoxy]benzoic acid (H2cob) and 1,10-phenanthroline (phen), were prepared and characterized. Complexes 3 and 4 show luminescence of the trivalent lanthanides. (Image credit: Lixin You.)
We designed and synthesized a new fluorescent probe G based on 4-bromobenzaldehyde, CH3I and 4-vinylpyridine. Probe G formed a 1 : 1 complex with Zn2+ that produced a large fluorescence enhancement and a red shift of ~95 nm. Under ultraviolet light, on addition of Zn2+, the fluorescent color of probe G changed from blue to yellow. The tripyridine derivative probe G can quickly detect and identify zinc ions with high selectivity and a low detection limit in aqueous solution. (Image credit: Qinghong Bai.)
A scalable methodology that allows particles based on trialkoxy siloxanes with non-polar substituents to be synthesised in a one-pot reaction through the controlled addition of the reactants is reported. By dispersing the trialkoxy silane precursor prior to addition to the reaction solution, excellent control of particle size and dispersity can be achieved for systems not normally compatible with Stober methods.
In the pursuit of new monomers for the sustainable production of polymers, the biomass-derived and platform molecule levoglucosenone (LGO, 1) as well as the pseudo-enantiomeric compound iso-levoglucosenone (iso-LGO, 3) were engaged in a series of Diels–Alder cycloaddition reactions with a range of cyclic dienes. Various manipulations of the resulting adducts provided new monomeric systems likely to be suitable for polymerisation.
The marine cone snail Conus victoriae produces a peptide, Vc1.1, which has potent pain killing activity and is a valuable lead in the design of novel analgesics. (Image credit: Meng-Wei Kan.)
This work introduces a unique nano-biosorbent made of a polyacrylonitrile–ZnO@β-cyclodextrin–chitosan nanofibrous nanocomposite. The nanocomposite’s effectiveness as a novel antibacterial and photocatalyst agent for eliminating methylene blue was evaluated. Results verified the production of the nanocomposite, which exhibited high efficiency for methylene blue removal and acceptable antibacterial activity. (Image credit: Dadkhoda Ghazanfari.)
1H NMR spectra of the boranes show that the two different group of hydrogens in the H3BXH3 (X═B, N and P) compounds have different roles and 11B NMR indicates the boron chemical environments are also different. (Image credit: Feng Wang.)
The analyses of spectra for a wide range of substituted toluenes indicate a large variation in methyl group structures, however, quantum chemistry calculations are shown to predict little variation. This discrepancy is attributed to an interaction between the methyl torsion (internal rotation) and vibrations affecting the experimental analyses. (Image credit: J. R. Gascooke and W. D. Lawrance.)
Why has no LnM(η1-H2) been reported so far? What conditions should a metal fragment fulfill to favor this coordination mode? We report our answer to these questions with a combination of DFT calculations and statistical analysis. (Image credit: L. Morán-González and F. Maseras.)
Three iridium(III) metalloligands containing different cyclometallating ligands were incorporated into Ca2+ metal–organic frameworks yielding luminescent materials. Changing the cyclometalling ligand altered the emission wavelength, highlighting the utility of this approach for the generation of tailored solid-state materials for applications including chemical sensing. (Image credit: C. Hua and T. U. Connell.)
Constructing a 3D structure is an effective strategy for overcoming the electrochemical performance issues of MXenes. Generally, 3D MXene structures, being rich in funcitonal groups, can improve energy storage performance by an increased specific surface area and porosity, and decreasing ion transport distance. Therefore, 3D MXene structures have great potential in high-performance energy storage and conversion applications.
In a typical computational chemistry study, the use of a small ‘basis set’ is more efficient but less accurate.  The accuracy can be improved in several ways, the obvious ones being the use of (1) a large but less efficient basis set, (2) a no-cost but less flexible correction, and (3) an optimally tuned small basis set.  Which is the best?  We are finding it out in this investigation. (Image credit: Bun Chan.)
The Science Threshold Learning Outcomes (TLOs) were developed by Prof. Brian Yates and Prof. Sue Jones, supported by Dr Jo-Anne Kelder, during 2010–2011 as part of the Learning and Teaching Academic Standards (LTAS) project. This manuscript documents their leadership and development of communities of practice, which have transformed tertiary science education in Australia. (Image credit: Daniel Southam.)
In this Primer Review, the topic of molecular photochromism is introduced and fundamental concepts expounded, which should enable researchers interested in the field. Additionally, a history of the development of the area is given which provides perspective on how a field develops. Moreover, key photochromic molecules and selected applications are showcased to provide the interested reader with an entry to this fascinating field of science and emerging technology. (Image credit: David Jago.)
Chiral oxazolidinones can be selectively cleaved from their N-acyl derivatives using LiOOH, LiOBn or LiSBn, but not LiOH, which instead favours opening of the oxazolidinone ring. DFT calculations show that the selectivity depends on the barrier for decomposition of the tetrahedral intermediate, which depends on the electron-donating capacity of the introduced nucleophile. (Image credit: Elizabeth Krenske.)
Thin films of two poly(dendrimer)s differing in conjugation length, steric bulk and surface groups were studied for the detection of trace quantities of nitro-based taggant and explosive vapours. Addition of first-generation biphenyl-based dendrons led to a decrease in mass density, an increase in analyte sorption and improved detection. (Image credit: Paul L. Burn.)
This work mainly explored the feasibility of amphoteric surfactants to improve the dispersion stability of TiO2 nanofluids. A nanofluid flooding system based on amphoteric surfactants and TiO2 nanoparticles with stable dispersion and remarkable oil displacement performance was constructed.