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101.
Patrick J. Moon Anis Fahandej‐Sadi Wenyu Qian Prof. Rylan J. Lundgren 《Angewandte Chemie (International ed. in English)》2018,57(17):4612-4616
The copper‐catalyzed decarboxylative benzylation of aryl and alkenyl boronic esters with electron‐deficient aryl acetates is reported. The oxidative coupling proceeds under mild, aerobic conditions and tolerates a host of potentially reactive electrophilic functional groups that would be problematic with traditional benzylation methods (aryl iodides and bromides, protic heteroatoms, aldehydes, Michael acceptors). A reaction pathway in which a benzylic nucleophile is generated by aryl acetate decarboxylation and in turn is intercepted by the catalyst to form diarylmethane products is supported by mechanistic studies. 相似文献
102.
Saoussen Hammami Afifa Bergaoui Naima Boughalleb Anis Romdhane Ines Khoja Monia Ben Halima Kamel Zine Mighri 《Comptes Rendus Chimie》2010,13(11):1397-1400
Phallusides 1,2,3 (1), Fasciculatin (2), Acanthelline (3), Axisonitrile (4), Oroïdin (5) and the Novel bromopyrolimidazolic compound Axinellizine (6) were evaluated for their antifungal effects against several phytopatogenic fungi and were found to possess considerable activities. Insecticidal effect of only Acanthellin (3) against the major pest of stored products Tribolium confusum Duv has been carried out using direct contact application method showing a significant inhibitory effect of the test material on the T. confusum Duv larvae growth. Forty-five percent mortality of the adults was achieved 8 days after treatment. 相似文献
103.
Kaiçar Ammous Bruno Allard Hatem Garrab Anis Ammous 《Journal of Thermal Analysis and Calorimetry》2007,90(1):307-314
In this paper, a measurement technique of losses in the switching cell, based on calorimetric technique is presented. A special
calorimeter was designed to be able to access the heat generated by an operating converter. Power component losses are studied
according to the cyclic ratio and to operating frequency and an extraction method of the different terms of these losses,
using calorimetric measurements, is presented.
An accurate expression of the switching losses in the power semiconductors devices is proposed. 相似文献
104.
Mohd Anis Ganaie Agbaje Lateef Uma Shanker Gupta 《Applied biochemistry and biotechnology》2014,172(4):2143-2159
Fructooligosaccharides are influential prebiotics that affect various physiological functions in such a way that they promote positive impact to health. They occur naturally in many fruits and vegetables in trace amounts. However, they are mainly produced commercially by the reaction of microbial enzymes with di- or polysaccharides, such as sucrose or inulin as a substrate. For maximum production of fructooligosaccharides on an industrial level, development of more enzymes with high activity and stability is required. This has attracted the attention of biotechnologists and microbiologists worldwide. This study aims to discuss the new trends in the production of fructooligosaccharide and its effect on numerous health qualities through which it creates great demand in the sugar market. 相似文献
105.
106.
Copper‐Catalyzed Arylation of Nitrogen Heterocycles from Anilines under Ligand‐Free Conditions 下载免费PDF全文
Dounia Toummini Dr. Anis Tlili Julien Bergès Prof. Fouad Ouazzani Dr. Marc Taillefer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(45):14619-14623
The arylation of pyrazole and derivatives can be achieved by coupling arenediazonium species (formed in situ from anilines) by using a catalytic system that employs low‐toxicity and inexpensive copper metal under very mild and ligand‐free conditions (T=20 °C). From other nitrogen heterocycles, the presence of an additive (NBu4I) significantly improves the efficiency of the catalytic system. These results represent the first examples of C?N bond formation from arenediazonium species. 相似文献
107.
Ahmed Sadeq. Al‐Fatesh Ahmed Aidid. Ibrahim Sajjad Haider Anis Hamza. Fakeeha 《中国化学会会志》2013,60(11):1297-1308
Dry reforming of methane (CH4) with carbon dioxide (CO2) catalysts produces synthesis gas at atmospheric pressure. Synthesis gas is important feed stock to chemical and petrochemical industries to produce chemicals such as methanol and ammonia. It is also a source of hydrogen that is potential to fuel cells. Reforming reactions have also environmental benefit as CO2 and CH4, which are classified as green house gases, that cause global warming, are consumed. Reforming with CO2 is attractive method since it can be employed in areas where water is not available. Considerable efforts have been made to obtain catalysts for dry reforming to achieve both high activity and good stability. In this review, we will take an over view of the dry reforming process and concentrate on the various catalysts used in the process, in general and Ni/Al2O3 catalytic system in particular and report the available data in the literature and the present state of the art for this process. 相似文献
108.
Sadia Khan Itrat Fatima Mehdi Hussain Kazmi Abdul Malik 《Helvetica chimica acta》2013,96(6):1176-1181
Allumines A and B ( 1 and 2 , resp.), two new steroidal alkaloids, and a new cyclopentene derivative, 3 , were isolated from the CHCl3‐soluble fraction of the whole plant of Allium victorialis. Their structures were elucidated by spectroscopic techniques, including 1D‐ and 2D‐NMR spectroscopy. 相似文献
109.
Anis Romdhane Jean-François Gallard M’hamed Ali Hamza Hichem Ben Jannet 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):612-618
Abstract The synthesis of new naphthopyranotriazolopyrimidines phosphonates 4a–i in good yields (74%–93%) has been accomplished via Michaelis–Arbusov rearrangement by the reaction of trialkyl phosphite with naphthopyranotriazolopyrimidines chloride 3a–e, which were obtained from α-functionalized iminoethers 1 in two steps. The synthesized compounds 4a–i were completely characterized by IR, 1H, 13C, and 31P NMR and HRMS. 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
110.