The macrocyclic nonaaza 3 + 3 amine based on diaminocyclopentane forms enantiopure helical complexes with lanthanide(III) ions. In contrast to analogous complexes based on 1,2-trans-diaminocyclohexane, no clear helicity process is observed. Crystal structures of these compounds show tight helical wrapping of the macrocycle around the lanthanide(III) ion leading to the formation of a double helix. In contrast, more "open" conformation is observed for the free macrocycle. Similar double-helical conformation of the ligand was also observed for the lead(II) complex. In the case of this complex the NMR spectra indicate a dynamic process in which the C2-symmetric molecule observed in the solid state gives rise to an effective, averaged D3-symmetry in solution at elevated temperatures.
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http://dx.doi.org/10.1039/c5dt02478a | DOI Listing |
Chem Asian J
January 2025
Chiang Mai University, Chemistry, 239 Huay Kaew Road, Muang District, 50200, Chiang Mai, THAILAND.
The Ph3P-I2-mediated reactions between isatins and amines were extensively investigated leading to the discovery of highly selective and divergent routes toward the synthesis of two distinct classes of indole-based frameworks. Through a strategic design of the reaction paths, we overcome potential side reactions to achieve convenient and straightforward one-pot methods to access either indoloquinazolines with C-12 carboxamide or 2-aminosubstituted indol-3-ones using the same reagent system. Mechanistic studies reveal the role of Ph3P-I2 in governing product selectivity, providing an efficient route to novel fused-indolone derivatives with promising applications in drug discovery and medicinal chemistry.
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January 2025
State Key Laboratory of NBC Protection for Civilian, State Key Laboratory of NBC Protection for Civilian,, Beijing, CHINA.
The root ducts play an important role in the plant's transport of nutrients from the soil. Based on the selective transport characteristics of plant roots, amino pillar[6]arene bionic porous root sub-nano channel membrane were constructed to remove Imazamox. Imazamox (IM) is an effective imidazolinone herbicide frequently utilized in soybean fields to control a wide range of annual grasses and broad-leaved weeds.
View Article and Find Full Text PDFChem Commun (Camb)
January 2025
Materials Chemistry Laboratory, Department of Chemistry, School of Natural Sciences, Shiv Nadar Institution of Eminence, Gautam Buddha Nagar, Uttar Pradesh 201314, India.
Cathode materials with both high capacity and high operating voltage are essential for advancing aqueous zinc-ion batteries (ZIBs). Conventional high-capacity materials, such as vanadium-based compounds, typically deliver low discharge voltages. In contrast, organic cathodes show high operating voltages but often exhibit limited capacity.
View Article and Find Full Text PDFBiol Aujourdhui
January 2025
Institut d'Écologie et des Sciences de l'Environnement de Paris (iEES Paris), Paris, France - Sorbonne Université, 4 place Jussieu, 75005 Paris, France.
The evolutionary success of angiosperms, which make up more than 95 percent of the world's terrestrial flora, is largely based on their interactions with animal pollinators. Indeed, it is estimated that, on average, 87.5 percent of flowering plants are pollinated by animals.
View Article and Find Full Text PDFChem Sci
January 2025
J. Mike Walker '66 Department of Mechanical Engineering, Texas A&M University College Station TX 77843 USA
This perspective work examines the current advancements in integrated CO capture and electrochemical conversion technologies, comparing the emerging methods of (1) electrochemical reactive capture (eRCC) though amine- and (bi)carbonate-mediated processes and (2) direct (flue gas) adsorptive capture and conversion (ACC) with the conventional approach of sequential carbon capture and conversion (SCCC). We initially identified and discussed a range of cell-level technological bottlenecks inherent to eRCC and ACC including, but not limited to, mass transport limitations of reactive species, limitation of dimerization, impurity effects, inadequate generation of CO to sustain industrially relevant current densities, and catalyst instabilities with respect to some eRCC electrolytes, amongst others. We followed this with stepwise perspectives on whether these are considered intrinsic challenges of the technologies - otherwise recommendations were disclosed where appropriate.
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