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Mohammad Rafiee

Bio: Mohammad Rafiee is an academic researcher from Shahid Beheshti University of Medical Sciences and Health Services. The author has contributed to research in topics: Cyclic voltammetry & Reaction rate constant. The author has an hindex of 28, co-authored 116 publications receiving 2668 citations. Previous affiliations of Mohammad Rafiee include Wisconsin Alumni Research Foundation & Institute for Advanced Studies in Basic Sciences.


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Journal ArticleDOI
TL;DR: This review provides a comprehensive survey of the electrochemical properties and electrocatalytic applications of aminoxyls, imidoxylS, and related reagents, of which the two prototypical and widely used examples are 2,2,6,6-tetramethylpiperidine N-oxyl (TEMPO) and phthalimide N- oxyl (PINO).
Abstract: N-Oxyl compounds represent a diverse group of reagents that find widespread use as catalysts for the selective oxidation of organic molecules in both laboratory and industrial applications. While turnover of N-oxyl catalysts in oxidation reactions may be accomplished with a variety of stoichiometric oxidants, N-oxyl reagents have also been extensively used as catalysts under electrochemical conditions in the absence of chemical oxidants. Several classes of N-oxyl compounds undergo facile redox reactions at electrode surfaces, enabling them to mediate a wide range of electrosynthetic reactions. Electrochemical studies also provide insights into the structural properties and mechanisms of chemical and electrochemical catalysis by N-oxyl compounds. This review provides a comprehensive survey of the electrochemical properties and electrocatalytic applications of aminoxyls, imidoxyls, and related reagents, of which the two prototypical and widely used examples are 2,2,6,6-tetramethylpiperidine N-oxyl (TEMPO) a...

537 citations

Journal ArticleDOI
TL;DR: In this article, a questionnaire survey consisting of 2400 householders was performed on Abadan residents to evaluate their knowledge, attitudes, and practices (KAP) towards solid waste (SW) reduction, source separation and recycling, collection and willingness to pay (WTP) for SW services.
Abstract: A questionnaire survey consisting of 2400 householders was performed on Abadan residents to evaluate their knowledge, attitudes, and practices (KAP) towards solid waste (SW) reduction, source separation and recycling, collection and willingness to pay (WTP) for SW services. The study has also covered the relationship between demographic variables and KAP towards SW management. The data analyzed suggests that the studied community had a very positive attitude to take part in SW source separation and recycling plans. However, the respondents not only showed low intimate knowledge of different steps of SW management, but were also weak to take practices about these steps. The KAP of SW source separation and recycling was influenced by demographic factors of age, education level, gender and occupation. It was further found that education level and occupation were two significant factors affecting residents’ WTP (χ2 = 24.083, p-value

204 citations

Journal ArticleDOI
TL;DR: The inexpensive, high-potential TEMPO derivative, 4-acetamido-TEMPO (ACT), exhibits higher electrocatalytic activity than AZADO and ABNO for the oxidation of primary and secondary alcohols.
Abstract: Bicyclic nitroxyl derivatives, such as 2-azaadamantane N-oxyl (AZADO) and 9-azabicyclo[3.3.1]nonane N-oxyl (ABNO), have emerged as highly effective alternatives to TEMPO-based catalysts for selective oxidation reactions (TEMPO = 2,2,6,6-tetramethyl-1-piperidine N-oxyl). Their efficacy is widely attributed to their smaller steric profile; however, electrocatalysis studies described herein show that the catalytic activity of nitroxyls is more strongly affected by the nitroxyl/oxoammonium redox potential than by steric effects. The inexpensive, high-potential TEMPO derivative, 4-acetamido-TEMPO (ACT), exhibits higher electrocatalytic activity than AZADO and ABNO for the oxidation of primary and secondary alcohols. Mechanistic studies provide insights into the origin of these unexpected reactivity trends. The superior activity of ACT is especially noteworthy at high pH, where bicyclic nitroxyls are inhibited by formation of an oxoammonium hydroxide adduct.

180 citations

Journal ArticleDOI
TL;DR: In this article, the authors compared the removal efficiencies of heavy metals, phenols, and cyanides, either in separate or simultaneous presence, and found that electrostatic attraction was the dominant removal mechanism in separate coagulation.

134 citations

Journal ArticleDOI
TL;DR: The method provides the basis for direct (in situ) or sequential benzylation of diverse nucleophiles using methylarenes as the alkylating agent and the hydrogen-atom transfer mechanism for C-H iodination allows C- H oxidation to proceed with minimal dependence on the substrate electronic properties.
Abstract: An electrochemical method has been developed for selective benzylic iodination of methylarenes. The reactions feature the first use of N-hydroxyphthalimide as an electrochemical mediator for C–H oxidation to nonoxygenated products. The method provides the basis for direct (in situ) or sequential benzylation of diverse nucleophiles using methylarenes as the alkylating agent. The hydrogen-atom transfer mechanism for C–H iodination allows C–H oxidation to proceed with minimal dependence on the substrate electronic properties and at electrode potentials 0.5–1.2 V lower than that of direct electrochemical C–H oxidation.

131 citations


Cited by
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TL;DR: This paper presents a new state-of-the-art implementation of the iChEM (Collaborative Innovation Center of Chemistry for Energy Materials) Key Laborotary of Catalysis, which automates the very labor-intensive and therefore expensive and therefore time-heavy and expensive process ofalysis.
Abstract: and Fuels Changzhi Li,† Xiaochen Zhao,† Aiqin Wang,† George W. Huber,†,‡ and Tao Zhang*,† †State Key Laborotary of Catalysis, iChEM (Collaborative Innovation Center of Chemistry for Energy Materials), Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China ‡Department of Chemical and Biological Engineering, University of WisconsinMadison, Madison, Wisconsin 53706, United States

1,977 citations

Journal ArticleDOI
TL;DR: This review discusses advances in synthetic organic electrochemistry since 2000 with enabling methods and synthetic applications analyzed alongside innate advantages as well as future challenges of electroorganic chemistry.
Abstract: Electrochemistry represents one of the most intimate ways of interacting with molecules. This review discusses advances in synthetic organic electrochemistry since 2000. Enabling methods and synthetic applications are analyzed alongside innate advantages as well as future challenges of electroorganic chemistry.

1,930 citations

Journal ArticleDOI
TL;DR: The chemistry of copper is extremely rich because it can easily access Cu0, CuI, CuII, and CuIII oxidation states allowing it to act through one-electron or two-Electron processes, which feature confer a remarkably broad range of activities allowing copper to catalyze the oxidation and oxidative union of many substrates.
Abstract: The chemistry of copper is extremely rich because it can easily access Cu0, CuI, CuII, and CuIII oxidation states allowing it to act through one-electron or two-electron processes. As a result, both radical pathways and powerful two-electron bond forming pathways via organmetallic intermediates, similar to those of palladium, can occur. In addition, the different oxidation states of copper associate well with a large number of different functional groups via Lewis acid interactions or π-coordination. In total, these feature confer a remarkably broad range of activities allowing copper to catalyze the oxidation and oxidative union of many substrates. Oxygen is a highly atom economical, environmentally benign, and abundant oxidant, which makes it ideal in many ways.1 The high activation energies in the reactions of oxygen require that catalysts be employed.2 In combination with molecular oxygen, the chemistry of copper catalysis increases exponentially since oxygen can act as either a sink for electrons (oxidase activity) and/or as a source of oxygen atoms that are incorporated into the product (oxygenase activity). The oxidation of copper with oxygen is a facile process allowing catalytic turnover in net oxidative processes and ready access to the higher CuIII oxidation state, which enables a range of powerful transformations including two-electron reductive elimination to CuI. Molecular oxygen is also not hampered by toxic byproducts, being either reduced to water, occasionally via H2O2 (oxidase activity) or incorporated into the target structure with high atom economy (oxygenase activity). Such oxidations using oxygen or air (21% oxygen) have been employed safely in numerous commodity chemical continuous and batch processes.3 However, batch reactors employing volatile hydrocarbon solvents require that oxygen concentrations be kept low in the head space (typically <5–11%) to avoid flammable mixtures, which can limit the oxygen concentration in the reaction mixture.4,5,6 A number of alternate approaches have been developed allowing oxidation chemistry to be used safely across a broader array of conditions. For example, use of carbon dioxide instead of nitrogen as a diluent leads to reduced flammability.5 Alternately, water can be added to moderate the flammability allowing even pure oxygen to be employed.6 New reactor designs also allow pure oxygen to be used instead of diluted oxygen by maintaining gas bubbles in the solvent, which greatly improves reaction rates and prevents the build up of higher concentrations of oxygen in the head space.4a,7 Supercritical carbon dioxide has been found to be advantageous as a solvent due its chemical inertness towards oxidizing agents and its complete miscibility with oxygen or air over a wide range of temperatures.8 An number of flow technologies9 including flow reactors,10 capillary flow reactors,11 microchannel/microstructure structure reactors,12 and membrane reactors13 limit the amount of or afford separation of hydrocarbon/oxygen vapor phase thereby reducing the potential for explosions. Enzymatic oxidizing systems based upon copper that exploit the many advantages and unique aspects of copper as a catalyst and oxygen as an oxidant as described in the preceding paragraphs are well known. They represent a powerful set of catalysts able to direct beautiful redox chemistry in a highly site-selective and stereoselective manner on simple as well as highly functionalized molecules. This ability has inspired organic chemists to discover small molecule catalysts that can emulate such processes. In addition, copper has been recognized as a powerful catalyst in several industrial processes (e.g. phenol polymerization, Glaser-Hay alkyne coupling) stimulating the study of the fundamental reaction steps and the organometallic copper intermediates. These studies have inspiried the development of nonenzymatic copper catalysts. For these reasons, the study of copper catalysis using molecular oxygen has undergone explosive growth, from 30 citations per year in the 1980s to over 300 citations per year in the 2000s. A number of elegant reviews on the subject of catalytic copper oxidation chemistry have appeared. Most recently, reviews provide selected coverage of copper catalysts14 or a discussion of their use in the aerobic functionalization of C–H bonds.15 Other recent reviews cover copper and other metal catalysts with a range of oxidants, including oxygen, but several reaction types are not covered.16 Several other works provide a valuable overview of earlier efforts in the field.17 This review comprehensively covers copper catalyzed oxidation chemistry using oxygen as the oxidant up through 2011. Stoichiometric reactions with copper are discussed, as necessary, to put the development of the catalytic processes in context. Mixed metal systems utilizing copper, such as palladium catalyzed Wacker processes, are not included here. Decomposition reactions involving copper/oxygen and model systems of copper enzymes are not discussed exhaustively. To facilitate analysis of the reactions under discussion, the current mechanistic hypothesis is provided for each reaction. As our understanding of the basic chemical steps involving copper improve, it is expected that many of these mechanisms will evolve accordingly.

1,326 citations

Journal ArticleDOI
TL;DR: Various application of ILs are reviewed by focusing on their use as electrolyte materials for Li/Na ion batteries, Li-sulfur batteries,Li-oxygen batteries, and nonhumidifiedfuel cells and as carbon precursors for electrode catalysts of fuel cells and electrode materials for batteries and supercapacitors.
Abstract: Ionic liquids (ILs) are liquids consisting entirely of ions and can be further defined as molten salts having melting points lower than 100 °C. One of the most important research areas for IL utilization is undoubtedly their energy application, especially for energy storage and conversion materials and devices, because there is a continuously increasing demand for clean and sustainable energy. In this article, various application of ILs are reviewed by focusing on their use as electrolyte materials for Li/Na ion batteries, Li-sulfur batteries, Li-oxygen batteries, and nonhumidified fuel cells and as carbon precursors for electrode catalysts of fuel cells and electrode materials for batteries and supercapacitors. Due to their characteristic properties such as nonvolatility, high thermal stability, and high ionic conductivity, ILs appear to meet the rigorous demands/criteria of these various applications. However, for further development, specific applications for which these characteristic properties becom...

1,096 citations

Journal ArticleDOI
01 Jan 1958-Nature
TL;DR: In this paper, the authors present an overview of the relationship between organic chemistry and natural products, focusing on the Stereochemistry and the Chemistry of Natural Products (SCHP).
Abstract: Organic Chemistry By Dr. I. L. Finar. Vol. 2: Stereochemistry and the Chemistry of Natural Products. Pp. xi + 733. (London and New York: Longmans, Green and Co., Ltd., 1956.) 40s. net.

1,037 citations