A Far-Infrared Study of the Structures of Tris(Methyl Methyl Phosphonate) Iron(III), Tris(EthylEthylphosphonate) Iron(III), and Tris(IsopropylMethylphosphonate) Iron(III)

In articles by Kokalas et al.^1,2 studies were made of the interaction of FeCl₃ with diisopropyl methylphosphonate (DIMP), diethyl ethylphosphonate (DEEP), and dimethyl methyl phosphonate (DMMP) and structures were proposed for the reaction products. When the reactions are run under much milder conditions, there is much evidence^3–5 to support a different mechanism than that proposed by Kokalas and an altogether different structure of the complexes formed. In the structures proposed by Kokalas et al. the iron atom is surrounded by six oxygen atoms and these are the only bonding atoms to the iron. But on the other hand, in donor-acceptor complexes as are formed in chemisorption reactions,^3–5 some of these sites are filled by chloride ions and this difference should be ascertained quite easily by far-infrared spectroscopy. It was the purpose of this study to look at the far-infrared data and either further substantiate the structures proposed or to propose new ones.     

Large‐Scale Synthesis of Helicene‐Like Molecules for the Design of Enantiopure Thin Films with Strong Chiroptical Activity

Helicenes are fascinating molecules owing to their unusual properties and applications in many fields from catalysis to organic electronics. Herein, we report a straightforward pathway for the synthesis of helicene‐like molecules on a gram scale in an enantiopure form. Thin‐film materials with good propagating optical properties and very high chiroptical responses have been grown by using pulsed laser ablation without altering the structure or the enantiopurity of the molecules. Moreover, electronic and vibrational circular dichroism spectroscopies coupled with theoretical calculations enabled some dependences of the chiroptical properties with the structure to be highlighted, for example, effects of rigidification, aromatization, or the state of matter (liquid versus solid).     

Second graders articulating ideas about linear functional relationships

In this paper, we explore the ideas that second grade students articulate about functional relationships. We adopt a function-based approach to introduce elementary school children to algebraic content. We present results from a design-based research study carried out with 21 second-grade students (approximately 7 years of age). We focus on a lesson from our classroom teaching experiment in which the students were working on a problem that involved a linear functional relationship (y = 2x). From the analysis of students’ written work and classroom video, we illustrate two different approaches that students adopt to express the relationship between two quantities. Students show fluency recontextualizing the problem posed, moving between extra-mathematical and intra-mathematical contexts.     

Well-setness and scalarization in set optimization

In this paper, we consider a notion of global well-setness for a set optimization problem using the excess function. We give sufficient conditions for well-setness and establish Dontchev–Zolezzi type measure for well-setness. Moreover, we relate this notion with well-setness notion for a scalar problem obtained by using generalized Gerstewitz’s function.     

Dual-fibre stretcher and coma as tools for independent 2nd and 3rd order tunable dispersion compensation in a fibre-based ‘scan-free’ time domain optical coherence tomography system

Dispersion compensation up to the third order is experimentally demonstrated by using a dual-fibre stretcher combined with the coma of an imaging lens, in a fibre-based scan-free time domain optical coherence tomography system, leading to an axial resolution of less than 3 μm.     

Synthesis,characterization, and antiplasmodial efficacy of sulfonamide-appended [1,2,3]-triazoles

A series of benzenesulfonamide-appended [1,2,3]-triazole hybrids was synthesized by using [3 + 2] cycloaddition of primary, secondary, and tertiary sulfonamide azides with various phenoxymethylacetylenes under click reaction conditions. After structural characterization, the compounds were subjected to in-silico absorption, distribution, metabolism, excretion and toxicity (ADMET) screening to evaluate their drug-likeness and other pharmacokinetic parameters. Furthermore, their in vitro antiplasmodial potential was assessed against Plasmodium falciparum (3D7) strain, and some of the synthesized compounds displayed promising antimalarial potency. On cytotoxicity evaluation using MTT cell viability assay, the most active candidate N-(4,6-dimethylpyridin-2-yl)-4-(4-(4-nitrophenoxy)methyl)-1H-[1,2,3]-triazol-1-yl)benzenesulfonamide ( 14 ; IC₅₀ 6.2 μg/mL) demonstrated CC₅₀ 7.5 μg/mL against human hepatocarcinoma (HUH-7) cells.     

Novel conductive characteristics of ITO:Ti films deposited by spin coating from colloidal precursor

Transparent semiconducting ITO:Ti thin films, prepared by a sol–gel process, has been deposited by spin-coating technique onto alkali-free glass substrates. The as-coated films were annealed in ambient air at 550 °C for 1 h and further annealed in a reducing atmosphere. The influences of the Ti content in the sol on the surface morphology, microstructure, optical properties and electrical resistivity have been investigated. These properties were found to depend on the Ti content in the coating sol. Ti addition led to dense smooth layers with larger crystallite size (20–30 nm). Double layers synthesized with Ti:ITO = 0.53 wt% and submitted to reducing treatment in forming gas exhibited the lowest sheet resistance R_□ = 60 Ω_□ with an average transmittance of 87% at 550 nm.     

Efficient Screening for Ternary Molecular Ionic Cocrystals Using a Complementary Mechanosynthesis and Computational Structure Prediction Approach

The discovery of molecular ionic cocrystals (ICCs) of active pharmaceutical ingredients (APIs) widens the opportunities for optimizing the physicochemical properties of APIs whilst facilitating the delivery of multiple therapeutic agents. However, ICCs are often observed serendipitously in crystallization screens and the factors dictating their crystallization are poorly understood. We demonstrate here that mechanochemical ball milling is a versatile technique for the reproducible synthesis of ternary molecular ICCs in less than 30 min of grinding with or without solvent. Computational crystal structure prediction (CSP) calculations have been performed on ternary molecular ICCs for the first time and the observed crystal structures of all the ICCs were correctly predicted. Periodic dispersion-corrected DFT calculations revealed that all the ICCs are thermodynamically stable (mean stabilization energy=−2 kJ mol⁻¹) relative to the crystallization of a physical mixture of the binary salt and acid. The results suggest that a combined mechanosynthesis and CSP approach could be used to target the synthesis of higher-order molecular ICCs with functional properties.