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Dr. Minqiang Jia Dr. Gianpiero Cera Daniele Perrotta Prof. Magda Monari Prof. Marco Bandini 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(32):9875-9878
A careful interplay between the π electrophilicity of a cationic AuI center and the basicity of the corresponding counterion allowed for the chemo‐ and regioselective inter‐ as well as intramolecular de‐aromatization of 2,3‐disubstituted indoles with allenamides. The silver‐free bifunctional Lewis acid/Brønsted base complex [{2,4‐(tBu)2C6H3O}3PAuTFA] assisted the formation of a range of densely functionalized indolenines under mild conditions. 相似文献
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Alessio Mezzi Eleonora Bolli Saulius Kaciulis Matteo Mastellone Marco Girolami Valerio Serpente Alessandro Bellucci Riccardo Carducci Riccardo Polini Daniele M. Trucchi 《Surface and interface analysis : SIA》2020,52(12):968-974
Thin films of barium fluorides with different thicknesses were deposited on GaAs substrate by electron beam evaporation. The aim of the work was to identify the best growth conditions for the production of coatings with a low work function suitable for the anode of hybrid thermionic-photovoltaic (TIPV) devices. The chemical composition and work function φ of the films with different thicknesses were investigated by X-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS). The lowest value of φ = 2.1 eV was obtained for the film with a thickness of ~2 nm. In the valence band spectra of the films at low kinetic energy, near the cutoff, a characteristic peak of negative electron affinity was present. This effect contributed to a further reduction of the film's work function. 相似文献
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Ji Hye Kim Alessandro Ruffoni Yasair S. S. Al‐Faiyz Nadeem S. Sheikh Daniele Leonori 《Angewandte Chemie (International ed. in English)》2020,59(21):8225-8231
Herein we report the development of a photocatalytic strategy for the divergent preparation of functionalized bicyclo[1.1.1]pentylamines. This approach exploits, for the first time, the ability of nitrogen‐radicals to undergo strain‐release reaction with [1.1.1]propellane. This reactivity is facilitated by the electrophilic nature of these open‐shell intermediates and the presence of strong polar effects in the transition‐state for C?N bond formation/ring‐opening. With the aid of a simple reductive quenching photoredox cycle, we have successfully harnessed this novel radical strain‐release amination as part of a multicomponent cascade compatible with several external trapping agents. Overall, this radical strategy enables the rapid construction of novel amino‐functionalized building blocks with potential application in medicinal chemistry programs as p‐substituted aniline bioisosteres. 相似文献
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Dotsevi Y. Sogah Daniele Perle-Treves N. Voyer W. F. Degrado 《Macromolecular Symposia》1994,88(1):149-163
A linear neutral repetitive peptide, (Leu-Gln-Pro)n (n = 1-100), an analog of the Ca2+ ion-binding domain of the matrix protein, amelogenin, has been synthesized. The polypeptide is mostly unordered in trifluoroethanol (TFE) at 25°C and its circular dichroism (CD) spectrum resembles that of the protein itself. In TFE the CD spectrum of (Leu-Gln-Pro)n reveals that the polypeptide interacts strongly with divalent cations Mg2+, Ca2+, Sr2+, and Ba2+ accompanied by conformational rearrangement from a random to a more-ordered one. In the presence of Li+, Na+ and K+ ions no such conformational change has been observed. The CD curves of the complexes suggest the presence of type I β-turns and reinforce the hypothesis that the region Gln112-Leu138 in amelogenin is the Ca2+-binding domain. In the solid state, powder X-ray diffraction suggests that the polymeric (LQP)n may exist as isolated “rigid rods”. 相似文献
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Dr. Daniele Paderni Dr. Eleonora Macedi Dr. Larisa Lvova Dr. Gianluca Ambrosi Prof. Mauro Formica Prof. Luca Giorgi Prof. Roberto Paolesse Prof. Vieri Fusi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(49):e202201062
A new series of ligands containing the 2-(2-hydroxy-3- naphthyl)-4-methylbenzoxazole (HNBO) fluorophore showed selectivity for Mg2+ ions, without the interference of Ca2+. The most promising representative L3 resulted the best performing sensor for Mg2+ both in solution and embedded in an all-solid-state optode, especially towards real samples of drinkable water. 相似文献
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Roberta Sanna Davide Sanna Valeria Alzari Daniele Nuvoli Sergio Scognamillo Massimo Piccinini Massimo Lazzari Emilia Gioffredi Giulio Malucelli Alberto Mariani 《Journal of polymer science. Part A, Polymer chemistry》2012,50(19):4110-4118
Thermoresponsive poly(N‐vinylcaprolactam) nanocomposite hydrogels containing graphene were successfully prepared by frontal polymerization. High concentration of graphene (5.0 mg/mL) was obtained by direct graphite sonication in the self‐same liquid monomer, thus avoiding any chemical manipulation and obtaining “real” graphene as nanofiller instead of one of its more or less oxidized derivative, which is what generally reported in published reports. Furthermore, the corresponding nanocomposites were obtained without using any solvent to be eventually removed. The materials were fully characterized by RAMAN, SEM, and TEM, and their swelling behavior and rheological properties were investigated. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献