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We present a novel, greener chloromethylation procedure for organosolv aspen lignin under mild reaction conditions without Lewis acid as a catalyst and in acetic acid as a solvent. This synthetic protocol provides a reliable approach to chloromethylated lignin (CML) and means to obtain valuable lignin derivatives. The resulted CML was subsequently transformed into 1-methylimidazolium lignin (ImL), which effectively serves as a stabilizing agent for Pd/CuO nanoparticles (Pd/CuO-NPs). To evaluate the versatility of developed lignin-based catalyst, we investigate its performance in a series of carbon-carbon bond formation reactions, including Suzuki-Miyaura, Sonogashira, Heck reactions, and azide-alkyne cycloaddition (click) reaction. Remarkably, this catalyst exhibited a high degree of catalytic efficiency, resulting in reactions with yields ranging from average to excellent. The heterogeneous catalyst demonstrated outstanding recyclability, enabling its reuse for at least 10 consecutive reaction cycles, with yields consistently falling within the range of 42 % to 84 %. A continuous flow reactor cartridge prototype employing Lignin@Pd/CuO-NPs was developed, yielding results comparable to those achieved in batch reactions. The utilization of Lignin@Pd/CuO-NPs as a catalyst showcases its potential to facilitate diverse carbon-carbon bond formation reactions and underscores its promising recyclability, aligning with the green chemistry metrics and principles of sustainability in chemical processes.
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Invited for this issue's cover are researchers from Tallinn University of Technology (TalTech). The image depicts the lignin chemical evolution route from raw biomass through a greener chloromethylation procedure developed by the research team. It showcases the transformation into lignin-supported metal nanoparticles, serving as a catalyst for various chemical reactions in both batch and continuous flow conditions. The Research Article itself is available at 10.1002/cssc.202301588.
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Farmers from South Asian countries spray insecticides without protective gear, which leads to insecticide exposure through dermal and nasal routes. Acetylcholinesterase plays a crucial role in controlling neuromuscular function. Organophosphate and carbamate insecticides inhibit acetylcholinesterase, which leads to severe neuronal/cognitive dysfunction, breathing disorders, loss of endurance, and death. To address this issue, an Oxime-fabric is developed by covalently attaching silyl-pralidoxime to the cellulose of the fabric. The Oxime-fabric, when stitched as a bodysuit and facemask, efficiently deactivates insecticides (organophosphates and carbamates) upon contact, preventing exposure. The Oxime-fabric prevents insecticide-induced neuronal damage, neuro-muscular dysfunction, and loss of endurance. Furthermore, we observe a 100% survival rate in rats when repeatedly exposed to organophosphate-insecticide through the Oxime-fabric, while no survival is seen when organophosphate-insecticide applied directly or through normal fabric. The Oxime-fabric is washable and reusable for at least 50 cycles, providing an affordable solution to prevent insecticide-induced toxicity and lethality among farmers.
Assuntos
Inseticidas , Oximas , Animais , Inseticidas/toxicidade , Ratos , Oximas/administração & dosagem , Oximas/farmacologia , Masculino , Compostos de Pralidoxima/farmacologia , Compostos de Pralidoxima/administração & dosagem , Têxteis , Inibidores da Colinesterase/administração & dosagem , Inibidores da Colinesterase/toxicidade , Acetilcolinesterase/metabolismo , Exposição Ocupacional/prevenção & controle , Exposição Ocupacional/efeitos adversos , Carbamatos/farmacologia , Carbamatos/administração & dosagem , Organofosfatos/toxicidade , Administração IntranasalRESUMO
The title compound, C18H23FO5, was synthesized by reacting diethyl malonate with 1-(4-fluoro-phen-yl)-3-methyl-but-2-en-1-one. The mol-ecule adopts a loose conformation stabilized by weak C-Hâ¯O and C-Hâ¯π inter-actions. In the crystal, the mol-ecules are joined by C-Hâ¯O contacts into infinite chains along the b-axis direction with a C(6) graph-set motif. Hirshfeld surface analysis and fingerprint plots demonstrate the predominance of Hâ¯H, Oâ¯H and Fâ¯H inter-molecular inter-actions in the crystal structure.
RESUMO
The title compound, C10H5BrF6O, synthesized via continuous stirring of 3,5-bis-(tri-fluoro-meth-yl) aceto-phenone with bromine in an acidic medium and concentrated under reduced pressure, crystallizes with four mol-ecules in the unit cell (Z = 4) and one formula unit in the asymmetric unit. In the crystal, mol-ecules are linked in a head-to-tail fashion into dimers along the b-axis direction through weak C-Hâ¯Br and C-Oâ¯Csp2 inter-actions. C-Hâ¯O, C-Fâ¯π and Fâ¯F inter-actions are also observed.