N,N-Dimethyl-Substituted Boron Ketoiminates for Multicolor Fluorescent Initiators and Polymers

Rapid Quantification of Oxytetracycline Based on Fluorescence Enhancement Influenced by pH

Accurate quantification of antibiotics in environmental samples is typically challenging due to the low antibiotic concentrations and the complexity of environmental matrices. This paper presents a fluorescence spectrometry method for determining oxytetracycline under alkaline conditions. The ionic distribution of the oxytetracycline solution was analyzed based on its dissociation constant. The dimethylamino group plays a crucial role in this method, as it promotes intramolecular charge transfer in the electronic excited state through its electron-donating capability with a lone electron pair. The presented method is straightforward, cost-effective, and holds potential for analyzing oxytetracycline in water sample after further investigation.

High Electrical Conductivity and Hole Transport in an Insightfully Engineered Columnar Liquid Crystal for Solution-Processable Nanoelectronics

Discotic liquid crystals (DLCs) are widely acknowledged as a class of organic semiconductors that can harmonize charge carrier mobility and device processability through supramolecular self-assembly. In spite of circumventing such a major challenge in fabricating low-cost charge transport layers, DLC-based hole transport layers (HTLs) have remained elusive in modern organo-electronics. In this work, a minimalistic design strategy is envisioned to effectuate a cyanovinylene-integrated pyrene-based discotic liquid crystal (PY-DLC) with a room-temperature columnar hexagonal mesophase and narrow bandgap for efficient semiconducting behavior. Adequately combined photophysical, electrochemical, and theoretical studies investigate the structure-property relations, logically correlating them with efficient hole transport. With a low reorganization energy of 0.2 eV, PY-DLC exhibits superior charge extraction ability from the contact electrodes at low values of applied voltage, achieving an electrical conductivity of 3.22 × 10-4 S m-1, the highest reported value for any pristine DLC film in a vertical charge transport device. The columnar self-assembly, in conjunction with solution-processable self-healed films, results in commendably elevated values of hole mobility (≈10-3 cm2 V-1s-1). This study provides an unprecedented constructive outlook toward the development of DLC semiconductors as practical HTLs in organic electronics.

Iron(III) and BF3·OEt2-Promoted O-Transfer Reaction of N-Aryl-α,β-Unsaturated Nitrones to Prepare Difluoroboron β-Ketoiminates

We described an iron(III) and BF3·OEt2-promoted oxygen transfer reaction of N-aryl-α,β-unsaturated nitrones to prepare various N,O-difluoroboron β-ketoiminates in good yields ranging from 24% to 87%. Control experiments revealed that the enaminone was the vital intermediate for the formation of N,O-difluoroboron β-ketoiminates, and iron(III) combined with BF3·OEt2 played as cocatalyst to promote the oxygen transfer reaction through intramolecular cyclization and N-O bond cleavage. More importantly, an estrone-derived N,O-difluoroboron β-ketoiminate was easily prepared in 40% yield from estrone in four steps.

Synthesis of N,O-bidentate organic difluoroboron complexes and their photophysical studies

We disclose a novel boron trifluoride induced C-H activation and difluoroboronation at room temperature, thus providing a straightforward gateway to a series of N,O-bidentate organic BF₂ complexes. The scope of the method is demonstrated with 24 examples. All the synthesized compounds exhibit fluorescence and some of them have large Stokes shifts.

Novel Ce-based coordination polymer nanoparticles with excellent oxidase mimic activity applied for colorimetric assay to organophosphorus pesticides

Cerium, as a lanthanide, has attracted considerable interest because of its excellent catalytic activity. Here, we propose a novel cerium-based coordination polymer nanoparticles named DPA-Ce-GMP, which have excellent oxidase-mimicking properties. Furthermore, a colorimetric probe that can act as an inhibitor to suppress the activity of acetylcholinesterase (AChE) was developed for detecting organophosphorus pesticides (OPs). DPA-Ce-GMP catalyzes colorless 3,3',5,5'-tetramethylbenzidine (TMB) to produce a blue color, and AChE catalyzes acetylthiocholine to produce thiocholine (TCh), which can weaken DPA-Ce-GMP-catalyzed TMB. After the addition of OPs, the enzymatic activity of AChE was inhibited to produce less amount of TCh, resulting in more DPA-Ce-GMP-catalyst oxidized TMB to show an increasing blue color. Dichlorvos, as the samples, with the limit of 0.024 μg/L. Overall, we believe that the colorimetric probe can be used for the rapid, low-cost, and large-scale field detection of OPs in food samples.

Controlling Molecular Aggregation-Induced Emission by Controlled Polymerization

In last twenty years, the significant development of AIE materials has been witnessed. A number of small molecules, polymers and composites with AIE activity have been synthesized, with some of these exhibiting great potential in optoelectronics and biomedical applications. Compared to AIE small molecules, macromolecular systems-especially well-defined AIE polymers-have been studied relatively less. Controlled polymerization methods provide the efficient synthesis of well-defined AIE polymers with varied monomers, tunable chain lengths and narrow dispersity. In particular, the preparation of single-fluorophore polymers through AIE molecule-initiated polymerization enables the systematic investigation of the structure-property relationships of AIE polymeric systems. Here, the main polymerization techniques involved in these polymers are summarized and the key parameters that affect their photophysical properties are analyzed. The author endeavored to collect meaningful information from the descriptions of AIE polymer systems in the literature, to find connections by comparing different representative examples, and hopes eventually to provide a set of general guidelines for AIE polymer design, along with personal perspectives on the direction of future research.

Recent progress in the applications of amino–yne click chemistry

This mini-review summarizes the recent research studies on the application of the amino–yne click reaction in surface immobilization, construction of drug delivery systems, preparation of hydrogel materials and synthesis of functional polymers.