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101.
Dr. Xiaoming Jie Dr. Qiu Sun Dr. Constantin G. Daniliuc Robert Knitsch Prof. Dr. Michael Ryan Hansen Prof. Dr. Hellmut Eckert Dr. Gerald Kehr Prof. Dr. Gerhard Erker 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(6):1269-1273
The active six-membered cyclo-FLP 6 undergoes a rapid P/B addition reaction to carbon dioxide. At elevated temperature, the resulting heterobicyclo[2.2.2]octane derived product 7 undergoes ring opening and equilibrates with the cyclotetramer (7)4 . In the large macrocyclic structure, four monomeric six-membered cyclo-FLP units are connected by four CO2 molecules to form the supramolecular ring system. The P/B cyclo-FLP 6 undergoes a variety of additional cycloaddition reactions. 相似文献
102.
103.
Igor E. Boldeskul Ivan F. Tsymbal 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1)
Phosphoalkenes (1), (R, RI, and RII = H, Hal, Nalk2) show alternative nucleophilic properties towards HX acids or transition metal salts, and depending upon reagent characteristics form addition products throught one of P=C double bond atoms. Coordination of a ligand to a cation by its π-electron donor is also observed due to quazidegeneration of higher occupied molecular orbital. 相似文献
104.
通过水热法,在黑磷(BP)纳米片表面生长FeOOH纳米材料,制备出FeOOH/BP纳米复合材料。作为电化学析氧反应(OER)催化剂,该复合材料在20 mA·cm-2时的过电位仅为191 mV,Tafel斜率为49.9 mV dec-1;在循环1 000圈后,过电位仅仅增加了3 mV,且循环过程中元素价态不变,表现出优秀的稳定性。纳米FeOOH负载于BP表面,客观上能隔断氧气对BP的氧化,保护BP的载流子传导性能。同时,生长的FeOOH颗粒尺度小,结晶性弱,这有利于丰富其活性位点,增大活性面积。 相似文献
105.
Wen-Bin Chen Gui-Yu Jin 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):543-549
In this article, we incorporated the organic phosphorus group on to a triazolothiadiazole ring to prepare the title compounds fused 1,2,4-triazolo[3,4-b][1,3,4]thiadiazole heterocyclic compounds. From the results on biological activities, we found that most compounds showed weak activities, and thus the structures need to be further optimized for improved activity. 相似文献
106.
Ali Ramazani Ebrahim Ahmadi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):565-567
Magnesium hydrogen sulfate powder was found to catalyze stereoselective conversion of dialkyl 2-(imido-N-yl)-3-(triphenylphosphorany-lidene)butanedioates to electron-poor (Z)-N-vinylimides in solvent-free conditions at 95°C 1 h in high conversions. Microwave also was found to catalyze the same reactions in the presence of magnesium hydrogen sulfate powder in solvent-free conditions in 3 min. 相似文献
107.
S. A. Grachev E. V. Kropachev G. I. Litvjakova N. V. Soroka 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2):105-106
Abstract Radiation chemistry of aminoalkylthiols and some derivatives (aminoalkyl-S-thiophosphates and aminoalkyl-S-thiosulfates among which are most effective radioprotectors) in aqueous solutions has been studied in order to establish the relation between the structure of these compounds and their radiation-chemical properties. Increase in the number of methylene groups between the sulfur atom and nitrogen atom in the aminothiol molecule from 2 to 4 and substitution of the amino group hydrogene by an alkyl radical has been found to be without appreciable effect both on the “spectra” of radiolisis products and rate constants for interaction of H, e? aq and OH with aminothiols 相似文献
108.
《应用有机金属化学》2017,31(11)
The phosphorus ylide [Ph3PCHC(O)C6H4‐NO2–4] reacted with Pd(OAc)2 to give the C,C‐orthometallated complex [Pd{κ2(C,C)‐C6H4PPh2C(H)CO(C6H4‐NO2–4)}(μ‐OAc)]2, which underwent bridge exchange reaction with NaN3, NaCl, KBr and KI, respectively, to afford the binuclear C,C‐orthopalladated complexes [Pd{κ2(C,C)‐C6H4PPh2C(H)CO(C6H4‐NO2–4)}(μ‐X)]2 (X = N3 ( 1 ), Cl ( 2 ), Br ( 3 ) and I ( 4 )). The complexes were identified using spectroscopy (infrared and NMR), CHNS technique and single‐crystal X‐ray structure analysis. Thereafter, palladium nanoparticles with narrow size distribution were easily prepared using the refluxing reaction of iodo‐bridged orthopalladated complex 4 with poly(N ‐vinyl‐2‐pyrrolidone) (PVP) as the protecting group. The PVP‐stabilized palladium nanoparticles were characterized using a variety of techniques including X‐ray diffraction, transmission and scanning electron microscopies, energy‐dispersive X‐ray spectroscopy, inductively coupled plasma analysis and Fourier transform infrared spectroscopy. The catalytic activity of the PVP‐stabilized palladium nanoparticles was evaluated in the Suzuki reaction of phenylboronic acid and the Heck reaction of styrene with aryl halides of varying electron densities. This catalyst exhibited excellent catalytic activity for Suzuki cross‐coupling reactions in ethanol–water. Notably, aryl chlorides which are cheaper and more accessible than their bromide and iodide counterparts also reacted satisfactorily using this catalyst. After completion of reactions, the catalyst could be separated using a simple method and used many times in repeat cycles without considerable loss in its activity. 相似文献
109.
Pallavi Singh Rakesh Tripathi Rajiv K. Verma Ganesh C. Nandi Ashutosh Gupta Maya S. Singh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2142-2151
A simple and efficient synthesis of previously unknown benzosubstituted dioxaphosphonines containing a quinoxaline subunit is described. Reasonably good yields of the products, mild reaction conditions, and convenient work-up are the advantages of this method. The procedure does not require any catalyst or activator and can be efficiently achieved via dianion cyclization. All the synthesized compounds have been characterized by satisfactory elemental analyses and spectral (IR, 1H, 13C, 31P NMR, and mass) studies. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. 相似文献