Search Results (465)

This work explores a novel and efficient synthetic approach to a new class of boron cluster derivatives via the nucleophilic addition of stabilized phosphorus ylides, Ph₃P=CHR² (R² = COOEt, CN), to a series of nitrilium salts of the closo-decaborate anion, [2-B₁₀H₉NCR¹]⁻ (R¹ = Me, Et, ⁿPr, ⁱPr, Ph). The reaction proceeds regio- and stereospecifically, affording a diverse range of iminoacyl phosphorane derivatives, [2-B₁₀H₉NH=C(R¹)C(PPh₃)R²]⁻, in high isolated yields (up to 95%). The obtained compounds (10 examples) were isolated as tetrabutylammonium or tetraphenylphosphonium salts and thoroughly characterized by multinuclear NMR (¹¹B, ¹H, ¹³C, ³¹P), high-resolution mass spectrometry, and single-crystal X-ray diffraction. The reaction feasibility was found to be strongly influenced by the steric hindrance of the R¹ group. Furthermore, the practical utility of these novel hybrids was demonstrated by employing the [2-B₁₀H₉NH=C(CH₃)C(COOC₂H₅)=PPh₃]⁻ anion as a highly effective membrane-active component in ion-selective electrodes. The developed tetraphenylphosphonium (TPP⁺) sensor exhibited a near-Nernstian response, a low detection limit of 3 × 10⁻⁸ M, and excellent selectivity over a range of common inorganic and organic cations, showcasing the potential of closo-borate-based ionophores in analytical chemistry. Full article

Subsurface deposition determines whether soils, aquifers, or ocean sediment represent a sink or temporary reservoir for microplastics. Deposition is generally studied by applying the Smoluchowski–Levich equation to determine a particle’s sticking efficiency, which relates the number of particles filtered by sediment to the probability of attachment occurring from an interaction between particles and sediment. Sticking efficiency is typically measured using column experiments or estimated from theory using the Interaction Force Boundary Layer (IFBL) model. However, there is generally a large discrepancy (orders of magnitude) between the values predicted from IFBL theory and the experimental column measurements. One way to bridge this gap is to directly measure a microparticle’s interaction forces using Atomic Force Microscopy (AFM). Herein, an AFM method is presented to measure sticking efficiency for a model polystyrene microparticle (2 μm) on a model geomaterial surface (glass or quartz) in environmentally relevant, synthetic freshwaters of varying ionic strength (de-ionized water, soft water, hard water). These data, collected over nanometer length scales, are compared to sticking efficiencies determined through traditional approaches. Force measurement results show that AFM can detect extremely low sticking efficiencies, surpassing the sensitivity of column studies. These data also demonstrate that the 75th to 95th percentile, rather than the mean or median force values, provides a better approximation to values measured in model column experiments or field settings. This variability of the methods provides insight into the fundamental mechanics of microplastic deposition and suggests AFM is isolating the physicochemical interactions, while column experiments also include physical interactions like straining. Advantages of AFM over traditional column/field experiments include high throughput, small volumes, and speed of data collection. For example, at a ramp rate of 1 Hz, 60 sticking efficiency measurements could be made in only a minute. Compared to column or field experiments, the AFM requires much less liquid (μL volume) making it effortless to examine the impact of solution chemistry (temperature, pH, ionic strength, valency of dissolved ions, presence of organics, etc.). Potential limitations of this AFM approach are presented alongside possible solutions (e.g., baseline correction, numerical integration). If these challenges are successfully addressed, then AFM would provide a completely new approach to help elucidate which subsurface minerals represent a sink or temporary storage site for microparticles on their journey from terrestrial to oceanic environments. Full article

The study investigates the performance of polyethersulfone (PES) ultrafiltration (UF) membranes modified with a coating of polymerizable bicontinuous microemulsion (PBM) for membrane bioreactor (MBR) applications. Two types of PBM-modified PES membranes—casting-coated and spray-coated—were compared with a commercial PES membrane. A laboratory side-stream MBR (ssMBR) was employed to treat model wastewater (MW) with activated sludge under aerobic conditions. The fouling propensity of the membranes in ssMBR was evaluated through the implementation of two protocols: (i) flux-step test to treat low-strength domestic model wastewater (DMW) and (ii) constant flux test to treat high-strength olive mill model wastewater (OMW). The findings indicated that both the commercial PES and PBM spray-coated PES membranes started to critically foul at 36 L m⁻² h⁻¹. The PBM spray-coated membranes showed enhanced fouling resistance in comparison to the PBM casting-coated membranes. The deposition of the biofouling layer was the thinnest on PBM spray-coated membranes, which can be attributed to the low surface charge and high hydrophilicity of the modified membrane surface. In contrast, deposition of a thicker fouling layer was found on the commercial PES membrane, which can be attributed to the relatively higher surface charge promoting organic adsorption. A comparison of the fouling trends exhibited by commercial PES and PBM spray-coated membranes in OMW treatment revealed that they have similar fouling tendencies. However, a notable distinction emerged when the PBM spray-coated membrane was observed to demonstrate a lower fouling propensity accompanied by comparatively thinner fouling layers. The results demonstrate that the PBM spray-coated membranes have enhanced fouling resistance and filtration efficacy in MBRs treating wastewater with diverse strengths, thereby affirming their potential for application in wastewater treatment systems. Full article

While organolithium reactions hold great promise in synthetic chemistry, their high reactivity, strong exothermicity, and the instability of intermediates often limit their application, making the effective control of reaction processes difficult in traditional batch reactors. This review systematically summarizes the latest advances in utilizing flow chemistry technology to address process challenges related to organolithium reactions from 2014 to 2025. From a process perspective, we systematically discuss the literature cases regarding three key themes: the synthesis of organic compounds applied in the pharmaceutical field, the development of novel methods centered on effective process control (reaction temperature, residence time, phase state, multi-step reaction sequence, and safety), and fundamental process research on continuous flow organolithium reactions. Analysis shows that continuous flow systems provide a powerful platform for fully realizing the potential of organolithium chemistry by enhancing heat/mass transfer and precisely controlling reaction parameters. This review emphasizes how flow chemistry technology not only improves process safety and efficiency but also enables transformations and process scaling that are difficult or impossible in batch modes, thus providing a novel process intensification method for modern synthetic chemistry. Full article

The emergence of electrically conductive polymeric materials has revolutionized the landscape of sustainable energy technologies, presenting unprecedented opportunities for advancing both photovoltaic conversion systems and electrochemical energy-storage platforms. These remarkable macromolecular materials exhibit distinctive characteristics including adjustable electronic band structures, exceptional mechanical adaptability, solution-phase processability, and cost-effective manufacturing potential. This extensive review provides an in-depth examination of the fundamental principles governing charge carrier mobility in conjugated polymer systems, explores diverse synthetic methodologies for tailoring molecular architectures, and analyzes their transformative applications across multiple energy technology domains. In photovoltaic technologies, electrically conductive polymers have driven major advancements in organic solar cells and photoelectrochemical systems, significantly improving energy conversion efficiency while reducing manufacturing costs. In electrochemical energy storage, their integration into supercapacitors and rechargeable lithium-based batteries has enhanced charge storage capability, accelerated charge–discharge processes, and extended operational lifespan compared with conventional electrode materials. This comprehensive analysis emphasizes emerging developments in hybrid composite architectures that combine conductive polymers with carbon-based nanomaterials, metal oxides, and other functional components to create next-generation flexible, lightweight, and wearable energy systems. By synthesizing fundamental materials chemistry with device engineering perspectives, this review illuminates the transformative potential of electrically conductive polymers in establishing sustainable, efficient, and resilient energy infrastructures for future technological landscapes. Full article

Compounds based on the pyrazoloquinazoline scaffold are of significant interest in synthetic organic chemistry owing to their potential biological activity. In this work, we describe the synthesis of a new derivative with this scaffold, 9-oxo-2-(p-tolyl)-4,9-dihydropyrazolo[5,1-b]quinazoline-3a(3H)-carboxylic acid, obtained by reacting 2,4-dioxo-4-(p-tolyl)butanoic acid with 2-aminobenzohydrazide in a 1:1 ratio when mixed in ethanol. The compound was characterized by ¹H/¹³C NMR, IR, and X-ray diffraction analysis. Full article

The application of Green Analytical Chemistry (GAC) principles in method development aims to reduce waste and replace hazardous solvents with environmentally friendly alternatives. Natural Deep Eutectic Solvents (NADESs) have recently emerged as sustainable replacements for traditional organic solvents. In this study, hydrophobic NADESs were used in dispersive liquid–liquid microextraction (DLLME) to extract four synthetic hallucinogenic phenethylamines (2C-B, 25B-NBOMe, 25C-NBOMe, and 25I-NBOMe) in urine samples. Nine NADESs were formed using menthol and different organic acids, with menthol–decanoic acid (1:1 molar ratio) providing the best extraction efficiency. A fractional factorial design identified pH, vortex speed, and vortex time as key factors, which were then optimized using a Box–Behnken design. The statistical model showed strong validity and high predictive power, and the optimal conditions (pH 12, vortex time 20 s, vortex speed 30,000 rpm, centrifugation at 14,000 rpm for 3 min) resulted in the highest recoveries. Greenness and operational sustainability, evaluated using ComplexGAPI, AGREEprep, BAGI, and SPRS tools, revealed clear advantages over existing extraction approaches. Overall, the proposed method represents a sustainable, white-chemistry–driven microextraction strategy suitable for clinical and forensic toxicological applications. Full article

In this study, an efficient and regioselective synthetic method was developed for the preparation of 3-hydroxy-3-((2-(naphthalen-2-yloxy)-2-oxoethoxy)carbonyl)pentanedioic acid, a multifunctional ether–ester compound of potential interest for pharmaceutical and material science applications. The target compound was synthesized via the nucleophilic substitution (SN2) and esterification reactions of 2-naphthyl chloroacetate with the monosodium salt of citric acid. Optimization of the reaction conditions was carried out by varying the molar ratio of the reagents, reaction temperature, and duration. The highest yield of 83% was achieved under the conditions of a 2:1 molar ratio of chloroacetate to citrate, a temperature of 70–80 °C, and a reaction time of 6 h. The enhanced product yield observed under these conditions is attributed to the dual reactivity of the citric acid monosodium salt, which contains a free hydroxyl group capable of undergoing SN2 etherification, and free carboxylic acid groups that participate in esterification with the electrophilic 2-naphthyl chloroacetate. The stoichiometric 2:1 ratio ensures that both reactive centers on the citrate anion are fully utilized, leading to efficient and selective transformation into the desired product. Mechanistically, the ether bond formation proceeds through the classical Williamson ether synthesis pathway, where the alkoxide formed from the hydroxyl group attacks the electrophilic carbon of the chloroacetate, displacing the chloride ion. Concurrently, esterification enhances molecular complexity and stability. The results underline the synthetic utility of citric acid derivatives in forming complex organic architectures via environmentally benign routes. This study not only contributes a practical approach to multifunctional molecule synthesis but also reinforces the applicability of green chemistry principles in ester–ether coupling strategies. Full article

Natural Product Synthesis (NPS) is a cornerstone of organic chemistry, historically rooted in the dual goals of structure elucidation and synthetic strategy development for bioactive compounds. Initially focused on identifying the structures of medicinally relevant natural products, NPS has evolved into a dynamic field with applications in drug discovery, immunotherapy, and smart materials. This evolution has been propelled by advances in reaction design, mechanistic insight, and the integration of green chemistry principles. A particularly promising development in NPS is the use of photochemistry, which harnesses light—a renewable energy source—to drive chemical transformations. Photochemical reactions offer unique excited-state reactivity, enabling synthetic pathways that are often inaccessible through thermal methods. Their precision and sustainability make them ideal for modern synthetic challenges. This review explores a wide range of photochemical reactions, from classical to contemporary, emphasizing their role in total synthesis. By showcasing their potential, the review aims to encourage broader adoption of photochemical strategies in the synthesis of complex natural products, promoting innovation at the intersection of molecular complexity, sustainability, and synthetic efficiency. Full article

Global concern over food waste and plastic pollution highlights the urgent need for sustainable, high-performance materials that can replace petroleum-based plastics. Bacterial cellulose (BC), a biopolymer synthesized through microbial fermentation by Komagataeibacter and related genera, shows exceptional purity, mechanical strength, biodegradability, and structural tunability. Following PRISMA principles, this review analyzed studies from PubMed, Scopus, and Web of Science covering the period 1960–November 2025. Search terms included “bacterial cellulose”, “Komagataeibacter”, “Gluconacetobacter”, “static culture”, “agitated culture”, “in situ modification”, “ex situ modification”, “fermentation”, and “food packaging”. Inclusion and exclusion criteria ensured that only relevant and high-quality publications were considered. The article summarizes major developments in BC biosynthesis, structural organization, and modification approaches that enhance mechanical, barrier, antioxidant, and antimicrobial properties for food packaging. Recent advances in in situ and ex situ functionalization are discussed together with progress achieved through synthetic biology, green chemistry, and material engineering. Evidence shows that BC-based composites can reduce oxygen and moisture permeability, strengthen films, and prolong food shelf life while maintaining biodegradability. Remaining challenges such as high cost, lengthy fermentation, and regulatory uncertainty require coordinated strategies focused on metabolic optimization, circular bioeconomy integration, and standardized safety frameworks to unlock BC’s full industrial potential. Full article

Pyridinium ylides, along with related azaheterocyclic ylides, are widely used in synthetic organic chemistry. However, reactions that yield stable zwitterionic adducts from these ylides remain underexplored. In this work, we demonstrate that the reaction of pyrrole-2,3-diones with in situ-generated pyridine-based azomethine ylides affords stable zwitterionic adducts, which are typically transient species in analogous processes. These betaines are used as key intermediates for the synthesis of cyclopropane-fused pyrroles or pyridine-2,3-diones via thermolysis in chlorobenzene. Full article

Electrochemiluminescence (ECL) has evolved into a powerful analytical technique due to its ultra-high sensitivity, low background noise, and precise electrochemical control. The development of efficient ECL emitters is central to advancing this technology for practical applications. Covalent organic frameworks (COFs) have recently emerged as promising candidates for constructing high-performance ECL systems. The tunable porosity, ordered π-conjugated structures, and versatile modular functionalities of COFs provide fast massive transport, effective electron transfer, rapid interfacial electrochemical reaction, and enhanced ECL emission performance. This review provides a comprehensive overview of the rational design strategies and structural engineering for COF-based ECL materials at the molecular level. Linkage chemistry, monomer selection (luminophores and π-conjugated non-ECL motifs), precise framework regulation, post-synthetic modification, composite formation, and other ECL enhancement strategies were discussed for developing COF-based ECL emitter. Both the incorporation of aggregation-induced emission and intramolecular charge transfer mechanisms are included to enhance ECL efficiency. Donor–acceptor conjugation, heteroatom element content, isomerism, substitution, and dimensional direction were regarded as effective strategies to regulate the electronic structure and band diagrams for designing high-performance ECL systems. The role of COFs as both active emitters and functional scaffolds for signal amplification is critically examined. Furthermore, their diverse analytical applications across biosensing, food safety, environmental monitoring, and chiral recognition are highlighted. By correlating structural features with ECL performance, this review offers insights into the design principles of next-generation reticular ECL materials and outlines future directions for their practical deployment in sensitive and selective sensing platforms. Full article

Methodological fusion of materials chemistry, which enables us to create materials, with nanotechnology, which enables us to control nanostructures, could enable us to create advanced functional materials with well controlled nanostructures. Positioned as a post-nanotechnology concept, nanoarchitectonics will enable this purpose. This review paper highlights the broad scope of applications of the new concept of nanoarchitectonics, selecting and discussing recent papers that contain the term ‘nanoarchitectonics’ in their titles. Topics include controls of dopant atoms in solid electrolytes, transforming the framework of carbon materials, single-atom catalysts, nanorobots and microrobots, functional nanoparticles, nanotubular materials, 2D-organic nanosheets and MXene nanosheets, nanosheet assemblies, nitrogen-doped carbon, nanoporous and mesoporous materials, nanozymes, polymeric materials, covalent organic frameworks, vesicle structures from synthetic polymers, chirality- and topology-controlled structures, chiral helices, Langmuir monolayers, LB films, LbL assembly, nanocellulose, DNA, peptides bacterial cell components, biomimetic nanoparticles, lipid membranes of protocells, organization of living cells, and the encapsulation of living cells with exogenous substances. Not limited to these examples selected in this review article, the concept of nanoarchitectonics is applicable to diverse materials systems. Nanoarchitectonics represents a conceptual framework for creating materials at all levels and can be likened to a method for everything in materials science. Developing technology that can universally create materials with unexpected functions could represent the final frontier of materials science. Nanoarchitectonics will play a significant part in achieving this final frontier in materials science. Full article

Isocyanide-based multicomponent reactions, such as the Ugi four-component reaction, are among the most relevant synthetic tools in modern organic chemistry. They have been successfully applied in natural product science for the synthesis of natural product analogs, for example, carbohydrates and steroids. However, the synthesis of analogs of other important groups, like triterpenoids, remains rarely studied. In the present work, we report the synthesis of four bis-amides via the Ugi reaction starting from masticadienonic acid, a triterpenoid isolated from Pistacia mexicana. Full article

Risdiplam is the first approved small-molecule therapy for spinal muscular atrophy (SMA), a severe, progressive neuromuscular disorder. In addition to its clinical significance, risdiplam is of a great interest for organic and medicinal chemistry due to its complex molecular architecture. Its structure incorporates three highly substituted heterocyclic fragments—imidazo[1,2-b]pyridazine, pyrido[1,2-a]pyrimidin-4-one, and 4,7-diazaspiro[2.5]octane—that serve as both versatile synthetic building blocks and critical pharmacophoric elements for drug design and discovery. The increasing scientific interest in risdiplam has led to numerous publications and patent applications that describe alternative synthetic methodologies. Recently, our group has also developed and introduced efficient, scalable manufacturing routes for the preparation of the target substance and the key intermediates of its synthesis. This mini-review systematically analyzes a plethora of risdiplam assembly strategies and synthetic approaches, covering developments from 2013 to the present. Full article