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Alessandra Pazini Luis Maqueira Harold C. Avila Felipe M. Valente Rian E. Aderne Davi Back Ricardo Q. Aucélio Marco Cremona Jones Limberger 《Tetrahedron letters》2018,59(31):2994-2999
The synthesis of a phenoxy-benzothiadiazole (BTD) derivative is reported for the first time. This derivative was employed as an intermediate in the obtention of two novel highly fluorescent aryl-phenoxy-BTD dyes. Their photophysical properties were evaluated in solution and the results indicate a strong intramolecular charge transfer (ICT) character in the excited state. The luminophore 3a, possessing a donor-BTD-phenoxide architecture, exhibits superior fluorescence quantum yield (0.67) than the designed acceptor-BTD-phenoxide dye (0.06). After electrochemical and photoluminescence characterization of thin films of 3a, an OLED with the configuration ITO/PEDOT:PSS/3a/TPBi/LiF/Al was constructed. This device displayed a green emission centered at 547?nm, with CIE coordinates of (0.40, 0.55). For comparison, an OLED using a previously reported luminescent BTD-pyridyl derivative was also constructed. The OLED made with the phenoxy-BTD derivative operated using less current density and led to higher irradiance and electrical stability, indicating the high potential of ArO-BTD dyes for future application in electroluminescent devices. 相似文献
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Structured emission spectra have been observed from ND3 excited at 2139 Å and 2144 Å. The emission is short-lived (τ < 10?10 s) and has been assigned to the ND3() → ND3() fluorescence transition. 相似文献
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The conjugate additions of (2-piperidyl)acetate esters to acetylenic sulfones, followed by LDA-promoted intramolecular acylations, afforded cyclic enaminones that were readily converted into the corresponding 4-substituted 2-keto- or 2-hydroxyquinolizidines by stereoselective reduction and desulfonylation. This procedure was applied to the total synthesis of (-)-lasubine II from methyl (S)-(2-piperidyl)acetate and 2-(3,4-dimethoxyphenyl)-1-(p-toluenesulfonyl)ethyne. Similarly, methyl (+/-)-(2-piperidyl)acetate and 1-(p-toluenesulfonyl)propyne provided (+/-)-myrtine. 相似文献
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David N. Harpp Thomas G. Back 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2-3):159-167
Abstract The low resolution mass spectra of alkyl and aryl sulfinamides containing alkyl, cycloalkyl, aryl and cyclic amine functions were recorded and the major fragmentation modes were elucidated with the aid of metastable peaks. In addition, the behavior of a variety of sulfinate esters upon electron-impact was similarly established. 相似文献
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Thomas G. Back Ziad Moussa Masood Parvez 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2004,116(10):1288-1290