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Triphenylphosphine‐Mediated Deoxygenative Reduction of CF3SO2Na and Its Application for Trifluoromethylthiolation of Aryl Iodides 下载免费PDF全文
Prof. Yi Yang Long Xu Siqi Yu Dr. Xiaoqiang Liu Yu Zhang Prof. David A. Vicic 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(3):858-863
We report herein a practical method for taming Langlois’ reagent CF3SO2Na to generate CuSCF3 by a triphenylphospine‐mediated deoxygenative reduction process. This chemistry highlights a novel utilization of the inherent CF3S skeleton of Langlois’ reagent as a CF3S feedstock under mild conditions. The CuSCF3 intermediate generated by this protocol can react with a wide array of supporting ligands to furnish several air‐stable [LCu(SCF3)] complexes as valuable trifluoromethylthiolating agents. In addition, the CuSCF3 intermediate can be directly employed for the trifluoromethylthiolation of (hetero)aryl iodides with operational simplicity and atomic efficiency. 相似文献
74.
Inside Back Cover: Stepwise Assembly of MII7 Clusters Revealed by Mass Spectrometry,EXAFS, and Crystallography (Chem. Eur. J. 51/2016) 下载免费PDF全文
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Ligustri Lucidi Fructus (LLF) is the fruits of Ligustrum lucidum Ait. (Oleaceae). This review based on nearly 80 literary sources discusses the knowledge of chemistry and biological effects of this species. Several types of chemical constituents considered as the characteristic and active constituents from LLF were isolated including 40 triterpenoids, 48 iridoids, 10 flavones, 10 phenylethanoid glycosides and others. Various extracts and individual compounds derived from this species have been found to possess a variety of pharmacological effects, e.g. anti-tumour, hepatoprotective, immune regulating, antioxidative and anti-ageing effects, anti-inflammation and reducing hypercholesterolaemia effects and so on. The results of data analysis on the chemical, pharmacological characteristics of LLF support the view that this species has many therapeutic properties and indicate its potential as an effective herbal remedy. Finally, some suggestions for further research on chemical and pharmacological properties are given in this review. Theoretical basis was given for further exploiting and utilising LLF. 相似文献
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Air‐Stable Spirofluorene‐Containing Ladder‐Type Bis(alkynyl)borane Compounds with Readily Tunable Full Color Emission Properties 下载免费PDF全文
Ben Yiu‐Wing Wong Dr. Hok‐Lai Wong Yi‐Chun Wong Dr. Mei‐Yee Chan Prof. Dr. Vivian Wing‐Wah Yam 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(42):15095-15106
A series of air‐stable spiro‐fused ladder‐type boron(III) compounds has been designed, synthesized, and the electrochemistry and photophysical behavior have been characterized. By simply varying the substituents on the pyridine ring and extending the π‐conjugation of the spiro framework, the emission color of these compounds can be easily fine‐tuned spanning the visible spectrum from blue to red. All compounds exhibit a broad and structureless emission band across the entire visible region, assigned as an intramolecular charge‐transfer transition originating from the thiophene of the spiro framework to the pyridine‐borane moieties. In addition, these compounds demonstrate high photoluminescence quantum yields of up to 0.81 in dichloromethane solution and 0.86 in doped thin films. Some of the compounds have also been employed as emissive materials, in which solution‐processed organic light‐emitting devices (OLEDs) with tunable emission colors spanning the visible spectrum from blue, green to red have been realized, demonstrating the potential applications of these boron compounds in OLEDs. 相似文献
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Benzyl protecting protocol was first employed in two routes for the concise synthesis of dopexamine dihydrochloride.This protecting group could be cleanly removed under mild condition and no unacceptable ion was brought to the final product.The total yield of route I was 43.8% from phenylacetic acid,while it was 54.1% of route II from 2-(3,4-bis(benzyloxy)phenyl)acetic acid.The titration purity of the final product was more than 99.5%,while any single or total impurities met the known standard of the drug by HPLC analysis.The measured residual palladium met an acceptable limit(<1 ppm) as an API for injection. 相似文献
79.
Ultrathin Co3S4 Nanosheets that Synergistically Engineer Spin States and Exposed Polyhedra that Promote Water Oxidation under Neutral Conditions 下载免费PDF全文
Youwen Liu Dr. Chong Xiao Mengjie Lyu Dr. Yue Lin Weizheng Cai Pengcheng Huang Prof. Wei Tong Prof. Youming Zou Prof. Yi Xie 《Angewandte Chemie (International ed. in English)》2015,54(38):11231-11235
Development of efficient and affordable electrocatalysts in neutral solutions is paramount importance for the renewable energy. Herein, we report that the oxygen evolution reaction (OER) performance of Co3S4 under neutral conditions can be enhanced by exposed octahedral planes and self‐adapted spin states in atomically thin nanosheets. A HAADF image clearly confirmed that the active octahedra with Jahn–Teller distortions were exposed exclusively. Most importantly, in the atomically thin nanosheets, the spin states of Co3+ in the octahedral self‐adapt from low‐spin to high‐spin states. As a result, the synergistic effect endow the Co3S4 nanosheets with superior OER performance, with exceptional low onset overpotentials of circa 0.31 V in neutral solutions, which is state‐of‐the‐art among inorganic non‐noble metal compounds. 相似文献
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