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21.
One‐pot reactions to produce 2,2′:6′,2″‐terpyridine (tpy) under mild conditions are described under both solventless and solvent‐assisted conditions. Tpy can be obtained in 32% yield in a simple one‐pot reaction, which can readily be scaled‐up to give large quantities of tpy. These new approaches are superior to those previously described because of the fast and efficient synthesis and purification of tpy. 相似文献
22.
Léna Sambe Victor R. de La Rosa Khaled Belal Dr. François Stoffelbach Dr. Joel Lyskawa Dr. François Delattre Marc Bria Prof. Graeme Cooke Prof. Richard Hoogenboom Prof. Patrice Woisel 《Angewandte Chemie (International ed. in English)》2014,53(20):5044-5048
A new class of polymeric thermometers with a memory function is reported that is based on the supramolecular host–guest interactions of poly(N‐isopropylacrylamide) (PNIPAM) with side‐chain naphthalene guest moieties and the tetracationic macrocycle cyclobis(paraquat‐p‐phenylene) (CBPQT4+) as the host. This supramolecular thermometer exhibits a memory function for the thermal history of the solution, which arises from the large hysteresis of the thermoresponsive LCST phase transition (LCST=lower critical solution temperature). This hysteresis is based on the formation of a metastable soluble state that consists of the PNIPAM–CBPQT4+ host–guest complex. When heated above the transition temperature, the polymer collapses, and the host–guest interactions are disrupted, making the polymer more hydrophobic and less soluble in water. Aside from providing fundamental insights into the kinetic control of supramolecular assemblies, the developed thermometer with a memory function might find use in applications spanning the physical and biological sciences. 相似文献
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Phenanthrenequinone undergoes highly efficient proton transfer processes in the presence of a thiourea-functionalised polystyrene copolymer whereas interactions with a similar benzyl-thiourea monomer show strong redox modulation of the quinone without proton transfer. 相似文献
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Electrochemically tuneable hydrogen bonding interactions are described between a phenyl-urea terminated dendrimer and phenanthrenequinone. 相似文献
27.
Legrand YM Gray M Cooke G Rotello VM 《Journal of the American Chemical Society》2003,125(51):15789-15795
A series of flavins were synthesized bearing electron-withdrawing and -donating substituents. The electrochemical properties of these flavins in a nonpolar solvent were determined. The recognition of these flavins by a diamidopyridine (DAP) receptor and the effect this receptor has on flavin redox potential was also quantified. It was found that the DAP-flavin binding affinity and the reduction potentials (E(1/2)) for both the DAP-bound and unbound flavins correlated well with functions derived from linear free energy relationships (LFERs). These results provide insight and predictive capability for the interplay of electronics and redox state-specific interactions for both abiotic and enzymatic systems. 相似文献
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Amination of propargylic sulfides with a ketomalonate-derived oxaziridine under metal free conditions gives N-Boc-N-allenylsulfenimides via [2,3]-sigmatropic rearrangement. 相似文献
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The motion of a holonomic scleronomic non-conservative mechanicalsystem with minimal dissipation is considered. As applicationsof the theory several problems are studied in detail. 相似文献
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