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Straightforward Synthesis of 5‐Bromopenta‐2,4‐diynenitrile and Its Reactivity Towards Terminal Alkynes: A Direct Access to Diene and Benzofulvene Scaffolds 下载免费PDF全文
Dr. Nicolas Kerisit Dr. Loïc Toupet Dr. Jean‐Claude Guillemin Dr. Yann Trolez 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(16):6042-6047
The high‐yielding synthesis of 5‐bromopenta‐2,4‐diynenitrile (BrC5N) was achieved for the first time. Its reactivity with triisopropylsilylacetylene and triisopropylsilylbutadiyne in the presence of copper and palladium as co‐catalysts and diisopropylamine was evaluated. It revealed an unprecedented cascade reaction leading to a diene in one case and to a benzofulvene in the other case, with a unique structure. Both of them were characterized by X‐ray crystallography, among other techniques. The mechanism of the reaction leading to the diene was investigated experimentally. Theoretical calculations at the DFT level suggest that the mechanism leading to the benzofulvene relies on a hexa‐dehydro Diels–Alder (HDDA)‐type of mechanism. This work constitutes an example of an unanticipated reactivity leading to an important increase of chemical complexity. 相似文献
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Shuwen He Peng Li Xing Dai Hong Liu Zhong Lai Dong Xiao Casey C. McComas Chunyan Du Yuehui Liu Jingjun Yin Qun Dang Nicolas Zorn Xuanjia Peng Ravi P. Nargund Anandan Palani 《Tetrahedron letters》2017,58(14):1373-1375
We report a general approach for the synthesis of 5,6-dihydroindolo-naphthyridine ring system via an intramolecular cyclization of the indole NH to an alkene moiety as the key step. 相似文献
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Nicolas Charalambakis George Chatzigeorgiou Yves Chemisky Fodil Meraghni 《Continuum Mechanics and Thermodynamics》2018,30(1):1-51
In this paper, a review of papers on mathematical homogenization of dissipative composites under small strains and on the interplay between homogenization procedure and dissipation due to mechanical work is presented. Moreover, a critical survey on the links between mathematical homogenization and computational homogenization is attempted. 相似文献
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Automated system measuring triple oxygen and nitrogen isotope ratios in nitrate using the bacterial method and N2O decomposition by microwave discharge 下载免费PDF全文
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Dr. Arif Music Dr. Andreas N. Baumann Florian Boser Nicolas Müller Florian Matz Prof. Thomas C. Jagau Dr. Dorian Didier 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(13):4322-4326
Readily accessible tetraorganoborate salts undergo selective coupling reactions under blue light irradiation in the presence of catalytic amounts of transition-metal-free acridinium photocatalysts to furnish unsymmetrical biaryls, heterobiaryls and arylated olefins. This represents an interesting conceptual approach to forge C−C bonds between aryl, heteroaryl and alkenyl groups under smooth photochemical conditions. Computational studies were conducted to investigate the mechanism of the transformation. 相似文献