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81.
Enantioselective Copper‐Catalyzed Azide–Alkyne Click Cycloaddition to Desymmetrization of Maleimide‐Based Bis(alkynes) 下载免费PDF全文
Tao Song Dr. Li Li Dr. Wei Zhou Dr. Zhan‐Jiang Zheng Dr. Yuan Deng Dr. Zheng Xu Prof. Dr. Li‐Wen Xu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(2):554-558
A copper catalyst system derived from TaoPhos and CuF2 was used successfully for catalytic asymmetric Huisgen [3+2] cycloaddition of azides and alkynes to give optically pure products containing succinimide‐ and triazole‐substituted quaternary carbon stereogenic centers. The desired products were obtained in good yields (60–80 %) and 85:15 to >99:1 enantiomeric ratio (e.r.) in this click cycloaddition reaction. 相似文献
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Deep oxidative desulfurization of benzothiophene and dibenzothiophene with a peroxophosphotungstate–ionic liquid brush assembly 下载免费PDF全文
A novel, efficient and reusable heterogeneous catalytic assembly of peroxophosphotungstate held in an ionic liquid brush was synthesized and an extraction and catalytic oxidative desulfurization (ECODS) procedure was developed for a model oil of benzothiophene (BT) and dibenzothiophene (DBT) using 30 wt% hydrogen peroxide as terminal oxidant and methanol as solvent under mild conditions. Several factors that affect sulfur removal were investigated in detail. The highest sulfur removal can reach 100% for BT in 7 h at 70 °C when the molar ratio of H2O2, S and catalyst is 10:1:0.025. The sulfur removal for DBT can also reach 100% in 4 h at 50 °C with the same molar ratio of H2O2, S and catalyst. The experimental results demonstrate that this ECODS process has no apparent scale‐up effect. The catalyst can be easily recovered (via simple filtration) and recycled five times without a significant decrease in activity. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Ionics - A novel stereoscopic snowflake-like CoO material is synthesized via a simple two-step process, including the hydrothermal process for the formation of the stereoscopic snowflake-like... 相似文献
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The palladium‐catalyzed direct C2‐ and further C7‐acylation of indoles with aldehydes have been developed. This method provides a convenient pathway toward a variety of mono‐ and diacylated indoles. 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
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Wen‐Jing Guo Yong‐Tao Wang De‐Xian Kong Jin‐Yun Wang Prof. Qiao‐Hua Wei Guo‐Nan Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(11):4205-4208
A heterometallic cluster [Ag6Au6(ethisterone)12] of an unprecedented topology was synthesized and characterized. A sensitive and specific probe for estrogen receptor α (ERα) has been developed for the first time based on the enhancement of the Ag6Au6 luminescence. 相似文献