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Prof. Jiao Jiao Wenzheng Nie Tao Yu Fan Yang Prof. Dr. Qian Zhang Feierdaiweisi Aihemaiti Tingjun Yang Xuanyu Liu Jiachen Wang Prof. Dr. Pengfei Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(15):4817-4838
Continuous-flow multi-step synthesis takes the advantages of microchannel flow chemistry and may transform the conventional multi-step organic synthesis by using integrated synthetic systems. To realize the goal, however, innovative chemical methods and techniques are urgently required to meet the significant remaining challenges. In the past few years, by using green reactions, telescoped chemical design, and/or novel in-line separation techniques, major and rapid advancement has been made in this direction. This minireview summarizes the most recent reports (2017–2020) on continuous-flow synthesis of functional molecules. Notably, several complex active pharmaceutical ingredients (APIs) have been prepared by the continuous-flow approach. Key technologies to the successes and remaining challenges are discussed. These results exemplified the feasibility of using modern continuous-flow chemistry for complex synthetic targets, and bode well for the future development of integrated, automated artificial synthetic systems. 相似文献
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Lars Rummel Jan M. Schümann Prof. Dr. Peter R. Schreiner 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(55):13699-13702
We present a computational analysis of hexaphenylethane derivatives with heavier tetrels comprising the central bond. In stark contrast to parent hexaphenylethane, the heavier tetrel derivatives can readily be prepared. In order to determine the origin of their apparent thermodynamic stability against dissociation as compared to the carbon case, we employed local energy decomposition analysis (LED) and symmetry-adapted perturbation theory (SAPT) at the DLPNO-CCSD(T)/def2-TZVP and sSAPT0/def2-TZVP levels of theory. We identified London dispersion (LD) interactions as the decisive factor for the molecular stability of heavier tetrel derivatives. This stability is made possible owing to the longer (than C−C) central bonds that move the phenyl groups out of the heavily repulsive regime so they can optimally benefit from LD interactions. 相似文献
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Mengfei Wang Dr. Kei Murata Prof. Kazuyuki Ishii 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(35):8994-9002
Mono- and di-nuclear tricarbonyl Re(I) tetraazaporphyrin complexes ( Re1TAP and Re2TAP ) are investigated and compared with Re(I) phthalocyanine complexes ( Re1Pc and Re2Pc ). Although Re2Pc is unstable in polar solvents, and easily undergoes demetallation reaction, the coordination of the TAP ligand significantly improves the tolerance toward polar solvents, affording more stability to Re2TAP . Additionally, the incorporation of [Re(CO)3]+ unit(s) and the TAP ligand results in remarkable positive shifts in both oxidation and reduction potentials. Consequently, the more positive oxidation potentials of the ReTAP complexes significantly increase the tolerance toward oxidation, while the reduction potential indicates that Re2TAP is suitable for a soluble electron acceptor. In contrast to Re1Pc and Re2Pc , Re1TAP and Re2TAP show unique broad Q bands, which can be attributed to the admixture of the π-π* and metal-to-ligand charge transfer characters, owing to the lowered π orbital energy in the TAP complexes. This study is useful for controlling electronic properties and realizing high stability in Pc analogues. 相似文献
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