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Unexpectedly Simple Synthesis of Benzazoles by tBuONa‐Catalyzed Direct Aerobic Oxidative Cyclocondensation of o‐Thio/Hydroxy/Aminoanilines with Alcohols under Air 下载免费PDF全文
Xinkang Shi Junmei Guo Dr. Jianping Liu Prof. Mingde Ye Prof. Dr. Qing Xu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(28):9988-9993
tBuONa‐catalyzed direct aerobic oxidative cyclocondensation reactions of readily available alcohols and o‐thio/hydroxy/aminoanilines under air have been developed and provide an efficient, practical, and green method for the synthesis of benzazoles. Mechanistic studies revealed that o‐substituted anilines promote the initial aerobic alcohol‐oxidation step, which explains the high reactivity and success of this unexpectedly simple and practical cyclocondensation method. 相似文献
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Dr. Miguel Peña‐López Dr. Helfried Neumann Prof. Dr. Matthias Beller 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(7):1818-1824
A general synthetic route to indoles from readily available anilines and epoxides by using ruthenium catalysis is described. This straightforward transformation allows a variety of indoles to be obtained in good yields by using [Ru3(CO)12]/1,1′‐bis(diphenylphosphino)ferrocene as the catalytic system. Water and hydrogen are formed as the only stoichiometric by‐products, making this process highly atom efficient. 相似文献
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Paula Gonçalves Fenga Nelson Ramos Stradiotto Maria Isabel Pividori 《Electroanalysis》2010,22(24):2979-2984
The growth of zinc hexacyanoferrate (ZnHCF) hybrid film on the surface of graphite‐epoxy composite (GEC) electrodes was demonstrated by cyclic voltammetry. Surface morphology of the hybrid film was investigated by using scanning electron microscopy. The effect of the type of monovalent cations on the redox behaviour of hybrid film was also studied. This effect indicated that the radius of the hydrated cation mainly determines the ion permeability of the film. 相似文献
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Răzvan C. Cioc Daan J. H. van der Niet Elwin Janssen Dr. Eelco Ruijter Prof. Dr. Romano V. A. Orru 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(21):7808-7813
A practical two‐stage one‐pot synthesis of N‐substituted β‐amino alcohols using aldehydes and isocyanides as starting materials has been developed. This method features mild reaction conditions, broad scope, and general tolerance of functional groups. Based on a less common central carbon–carbon bond disconnection, this protocol complements traditional approaches that involve amines and various carbon electrophiles (epoxides, α‐halo ketones, β‐halohydrins). Medicinally relevant products can be prepared in a concise and efficient way from simple building blocks, as demonstrated in the synthesis of the antiasthma drug salbutamol. Upgrading the synthesis to an enantioselective variant is also feasible. 相似文献
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Jianhui Deng Qiujun Lu Naxiu Mi Prof. Haitao Li Meiling Liu Prof. Mancai Xu Prof. Liang Tan Prof. Qingji Xie Prof. Youyu Zhang Prof. Shouzhuo Yao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(17):4993-4999
Carbon nanodots (C‐dots) show great potential as an important material for biochemical sensing, energy conversion, photocatalysis, and optoelectronics because of their water solubility, chemical inertness, low toxicity, and photo‐ and electronic properties. Numerous methods have been proposed for the preparation of C‐dots. However, complex procedures and strong acid treatments are often required, and the as‐prepared C‐dots tend to be of low quality, and in particular, have a low efficiency for photoluminescence. Herein, a facile and general strategy involving the electrochemical carbonization of low‐molecular‐weight alcohols is proposed. As precursors, the alcohols transited into carbon‐containing particles after electrochemical carbonization under basic conditions. The resultant C‐dots exhibit excellent excitation‐ and size‐dependent fluorescence without the need for complicated purification and passivation procedures. The sizes of the as‐prepared C‐dots can be adjusted by varying the applied potential. High‐quality C‐dots are prepared successfully from different small molecular alcohols, suggesting that this research provides a new, highly universal method for the preparation of fluorescent C‐dots. In addition, luminescence microscopy of the C‐dots is demonstrated in human cancer cells. The results indicate that the as‐prepared C‐dots have low toxicity and can be used in imaging applications. 相似文献
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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
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采用直接混合法制得平均尺寸小于50 nm的六氰合铁酸钴纳米粒子,元素分析表明其计量学分子式为K0.2Co1.4[Fe(CN)6]•xH2O,红外光谱证明此物质是由铁磁性的CoII1.5[FeIII(CN)6]和反铁磁性的KCoIII[FeII(CN)6]组成,并含有一定量的结晶水。用六氰合铁酸钴纳米粒子修饰的玻碳电极具有良好的稳定性和可逆的循环伏安行为,其电化学特征受溶液中配对阳离子种类和支持电解质浓度的影响。作为电极表面的媒介体,该薄膜对多巴胺的氧化还原具有电催化作用。 相似文献
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Ming Gong Prof. Dr. Jing‐Mei Huang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(40):14293-14296
A mild method for the direct C?H/N?H coupling between γ‐lactams and anilines through electrochemical oxidation has been developed. The protocol proceeded smoothly without metal catalysts at room temperature to afford γ‐substituted γ‐lactams in good yields. It has been revealed that the quasi‐divided cell which provided high current density on the anode was crucial for this reaction. 相似文献
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Manganese‐Catalyzed Dehydrogenative Alkylation or α‐Olefination of Alkyl‐Substituted N‐Heteroarenes with Alcohols 下载免费PDF全文
Dr. Guoying Zhang Dr. Torsten Irrgang Thomas Dietel Fabian Kallmeier Prof. Dr. Rhett Kempe 《Angewandte Chemie (International ed. in English)》2018,57(29):9131-9135
Catalysis with earth‐abundant transition metals is an option to help save our rare noble‐metal resources and is especially interesting when novel reactivity or selectivity patterns are observed. We report here on a novel reaction, namely the dehydrogenative alkylation or α‐olefination of alkyl‐substituted N‐heteroarenes with alcohols. Manganese complexes developed in our laboratory catalyze the reaction with high efficiency whereas iron and cobalt complexes stabilized by the same ligands are essentially inactive. Hydrogen is liberated during the reaction, and bromine and iodine functional groups as well as olefins are tolerated. A variety of alkyl‐substituted N‐heteroarenes can be functionalized, and benzylic and aliphatic alcohols undergo the reaction. 相似文献
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Sina Rösler Michael Ertl Dr. Torsten Irrgang Prof. Dr. Rhett Kempe 《Angewandte Chemie (International ed. in English)》2015,54(50):15046-15050
The implementation of inexpensive, Earth‐abundant metals in typical noble‐metal‐mediated chemistry is a major goal in homogeneous catalysis. A sustainable or green reaction that has received a lot of attention in recent years and is preferentially catalyzed by Ir or Ru complexes is the alkylation of amines by alcohols. It is based on the borrowing hydrogen or hydrogen autotransfer concept. Herein, we report on the Co‐catalyzed alkylation of aromatic amines by alcohols. The reaction proceeds under mild conditions, and selectively generates monoalkylated amines. The observed selectivity allows the synthesis of unsymmetrically substituted diamines. A novel Co complex stabilized by a PN5P ligand catalyzes the reactions most efficiently. 相似文献
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A Gold(I)‐Catalyzed Domino Coupling of Alcohols with Allenes Enables the Synthesis of Highly Substituted Indenes 下载免费PDF全文
Alexander Preinfalk Dr. Antonio Misale Prof. Dr. Nuno Maulide 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(41):14471-14474
The reaction of aryl‐substituted allenes with alcohols under gold catalysis led to highly substituted indenes in good yields, with low catalyst loading and under mild conditions. During this domino transformation, two C?C bonds are formed with water as the only byproduct. 相似文献