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41.
42.
AbstractA convenient and efficient procedure for the synthesis of 2-substituted-6,7-dihydrobenzo[d]oxazol-4(5H)-ones and 2-aryl-6,7-dihydrobenzofuran-4(5H)-ones through a Rh2(OAc)4-catalyzed C≡X (X?=?N, C) insertion of cyclic 2-diazo-1,3-diketones with nitriles and aromatic alkynes has been developed. This reaction uses readily available starting materials and stable cyclic 2-diazo-1,3-diketone compounds, with desired products formed in good to high yields. A tentative mechanism involving a C≡X bond insertion and 1,5-dipolar electrocyclization/ring opening and cyclization sequence for this reaction is proposed. 相似文献
43.
Chiral N-[1-benzyl-2-hydroxyethyl]-3-[2-oxo-pyrrole]propionamide (C16H22N2O3) was obtained unexpectedly from the reaction of oxazoline involving pyrrolidone with copper acetate monohydrate, and the structure was characterized by NMR, IR, elemental analysis, and X-ray analysis. 相似文献
44.
Yue Hangbo Xu Chao Yao Jiachang He Ming Yin Guoqiang Cui Yingde Yang Chufen Guo Jianwei 《Cellulose (London, England)》2022,29(10):5869-5881
Cellulose - The development of plant adhesive with good bonding strength, water resistance and thermal stability remains challenging to replace formaldehyde-based adhesive resins that usually... 相似文献
45.
Dingzhong Li Wensheng Zhang Dr. Longzhi Zhu Prof. Dr. Shuang-Feng Yin Prof. Dr. Nobuaki Kambe Prof. Dr. Renhua Qiu 《ChemistryOpen》2022,11(5):e202200023
An efficient hydrazine substitution of p-nitro-aryl fluorides with hydrazine hydrates catalyzed by FeO(OH)@C nanoparticles is described. This hydrazine substitutions of p-nitro-aryl fluorides bearing electron-withdrawing groups proceeded efficiently with high yield and selectivity. Similarly, hydrogenations of p-nitro-aryl fluorides containing electron-donating groups also smoothly proceeded under mild conditions. Furthermore, with these prepared aryl hydrazines, some phthalazinones, interesting as potential structures for pharmaceuticals, have successfully been synthesized in high yields. 相似文献
46.
Li Chao Yin Siyu Zhou Hongbo Zhang Yajiao Li Yongxiu Chen Yufeng 《Journal of Sol-Gel Science and Technology》2021,99(2):430-443
Journal of Sol-Gel Science and Technology - A drug delivery system with near-infrared emissions response to drug delivery and release is essential as marking or targeting drug delivery system. For... 相似文献
47.
48.
Haibao?Shao Chunlei?WangEmail author Shuhong?Xu Zhuyuan?Wang Haihong?Yin Yiping?CuiEmail author 《Journal of fluorescence》2015,25(2):305-310
Controllable doping is an effective way of tuning the properties of semiconductor nanocrystals (NCs). In this work, a simple strategy of fast doping Cu ions into ZnSe NCs under ambient conditions was proposed. The principle of doping is based on hydrazine (N2H4) promoted cation exchange reaction. By direct addition of Cu ion stock solution into the preformed ZnSe NCs, Cu doped ZnSe NCs can be obtained. Furthermore, the emission of doped NCs can be tuned by changing the amount of impurity ion addition. The cation exchange reaction is facilitated by three factors: 1) N2H4 addition, 2) fast impurity ions, and 3) partial stabilizer removal. The proposed cation exchange reaction in aqueous solution could be an alternate route for NC doping as well as synthesis of ionic NCs. 相似文献
49.
Skeleton Decoration of NHCs by Amino Groups and its Sequential Booster Effect on the Palladium‐Catalyzed Buchwald–Hartwig Amination 下载免费PDF全文
Yin Zhang Dr. Vincent César Golo Storch Dr. Noël Lugan Dr. Guy Lavigne 《Angewandte Chemie (International ed. in English)》2014,53(25):6482-6486
A challenging synthetic modification of PEPPSI‐type palladium pre‐catalysts consisting of a stepwise incorporation of one and two amino groups onto the NHC skeleton was seen to exert a sequential enhancement of the electronic donor properties. This appears to be positively correlated with the catalytic performances of the corresponding complexes in the Buchwald–Hartwig amination. This is illustrated, for example, by the quantitative amination of 4‐chloroanisole by morpholine within 2 h at 25 °C with a 2 mol % catalyst/substrate ratio or by a significant reduction of catalytic loading (down to 0.005 mol %) for the coupling of aryl chlorides with anilines (max TON: 19 600). 相似文献
50.
1,3-benzodioxole-5-yl-methyl-maleimide (BDOMM), a type of hydrogen-abstraction photoinitiator with both hydrogen donor and acceptor in one molecule for free radical photopolymerization, was synthesized through the reaction of piperonyl amine and maleic anhydride and characterized by IR, UV and 1H NMR spectroscopy. The results obtained indicated that the introduction of BDOMM could avoid the use of additional amine coinitiator, decrease the leachablity of photoinitiator and maintain high photo-initiation efficiency. 相似文献