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991.
992.
Several benzene (or phenylmethane) sulfinate esters were synthesized in 53–98% yields from the corresponding methoxymethyl (MOM) sulfides employing NBS as oxidant. 相似文献
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995.
Huijie He Xu Fang Dr. Dong Zhai Wei Zhou Yimeng Li Wenling Zhao Dr. Chengcheng Liu Dr. Zhen Li Prof. Weiqiao Deng 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(58):14390-14395
Imines are important intermediates in drug synthesis. Photocatalytic aerobic oxidative coupling of amines has been considered as a clean and promising way to produce imines and has attracted great attention. Herein, we designed and synthesized a novel two-dimensional porphyrin-based covalent organic framework (Por-BC-COF) which adopts an AA stacking mode with excellent crystallinity, high Brunauer–Emmett–Teller surface areas (1200 m2 g−1), wide light absorption range (200–1300 nm) and good stability in a variety of organic solvents. Por-BC-COF can be used as a metal-free heterogeneous photocatalyst for the photocatalytic oxidation of amines to imines under visible light and red light with a high yield (97 %). This work presents a novel and efficient COF photocatalyst in the application of light-driven organic synthesis. 相似文献
996.
Jie Feng Hongyang Zhao Wajid Ali Dandan Yin Xinyang Li Nawab Ali Khan Prof. Shujiang Ding 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(71):17818-17823
Coordination polymers are promising cathode materials for rechargeable alkaline batteries. Therefore, the precise modulation of these cathodes by chemical structure and in-depth structure transform study is necessary. Here, two model coordination polymer battery cathodes were designed to demonstrate the dynamic structure–performance relationship. We studied the electrochemical performance of two kinds of nickel-based coordination polymer, comprising a planar 2D cyanide-bridged network and a 3D cyanide-bridged network pillared by pyrazine molecules. The 2D coordination polymer showed serious voltage degradation with poor rate capability, whereas the 3D coordination polymer exhibited stable voltage output coupled with high rate at various current densities. The investigation revealed the underlining relationship of plateau voltage degradation and hydrolysis process of electrodes. It was revealed that the pyrazine pillar molecules in the 3D coordination polymer could suppress the hydrolysis and lead to the in situ formation of partially hydrolyzed structure with excellent electrochemical kinetics; this exhibited obvious smaller peak separation (27 mV compared with 149 mV) and hence an almost twofold increase in capacity retention (31.9 to 50.0 %) and energy density retention (18.2 to 35.9 %) at 10 A g−1. 相似文献
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998.
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1000.
Selective Oxidation of Alcohols with a New Reagent: Iron(III) Nitrate Supported on Aluminum Silicate
A selective and effective oxidation of alcohols, except aliphatic alcohols, such as 1‐hexanol or 1‐octyl alcohol, to the corresponding aldehydes and ketones using a new reagent, iron(III) nitrate supported on aluminum silicate, under heterogeneous conditions with reflux with 85–98% yield is described. 相似文献