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Wet carbon-based solid acid/NaNO_3 as a mild and efficient reagent for nitration of aromatic compound under solvent free conditions 被引量:5
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作者 Arash Shokrolahi Abbas Zali Mohammad Hossein Keshavarz 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第9期1064-1066,共3页
Nitro aromatic compound can be obtained in high yields via nitration of aromatic compound with wet carbon-based solid acid and NaNO_3 under solvent free oxidation at room temperature.
关键词 Carbon-based solid acid Sodium nitrate NITRATION solvent free conditions
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Microwave-assisted chemoselective copper-catalyzed amination of o-chloro and o-bromobenzoic acids using aromatic amines under solvent free conditions 被引量:2
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作者 Yaghoub Sarrafi Manijeh Mohadeszadeh Kamal Alimohammadi 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第7期784-788,共5页
Copper-catalyzed synthesis of N-aryl anthranilic acid derivatives using effective amination of 2-chloro and 2-bromobenzoic acid under microwave irradiation is reported. Some of the advantages of this method are high c... Copper-catalyzed synthesis of N-aryl anthranilic acid derivatives using effective amination of 2-chloro and 2-bromobenzoic acid under microwave irradiation is reported. Some of the advantages of this method are high chemoselectivity, short reaction times, ease of work up procedure and elimination of the need for acid protection. 2009 Published by Elsevier B.V. on behalf of Chinese Chemical Society. 展开更多
关键词 MICROWAVE-ASSISTED COPPER-CATALYZED solvent free AMINATION N-Aryl anthranilic acid
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Investigation on Organic Solvent Free Toluene Oxidative Bromination Reaction Catalyzed by HTS Zeolite 被引量:2
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作者 Peng Xinxin Xia Changjiu +3 位作者 Lin Min Zhu Bin Luo Yibin Shu Xingtian 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2020年第4期1-9,共9页
The toluene oxidative bromination reaction catalyzed by hollow titanium silicalite(HTS)zeolite in aqueous medium was investigated by employing H2O2 and HBr under mild conditions without the need for organic solvent.A ... The toluene oxidative bromination reaction catalyzed by hollow titanium silicalite(HTS)zeolite in aqueous medium was investigated by employing H2O2 and HBr under mild conditions without the need for organic solvent.A high toluene conversion(90.7%)and high selectivity of mono-bromotoluene(99.0%)was achieved under the optimal reaction conditions.The UV-Raman spectroscopy was applied for the mechanism study and the result reveals that HTS is efficient for catalyzing the oxidation reaction of HBr with H2O2 to produce abundant active bromine species,which can further facilitate the toluene electrophilic bromination reaction.A two-step toluene bromination reaction mechanism involving the HTS catalyzed active bromine species“generation-conversion-utilization”process is proposed based on the UV-Raman spectroscopy analysis. 展开更多
关键词 titanium silicalite oxidative bromination organic solvent free H2O2/HBr polybromine ion
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Zinc chloride catalyzed synthesis of 5-substituted 1H-tetrazoles under solvent free condition
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作者 Shahnaz Rostamizadeh Hamid Ghaieni +1 位作者 Reza Aryan Ali Amani 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第11期1311-1314,共4页
Zinc chloride is an efficient and safe catalyst in the [3 + 2] cycloaddition reaction of organic nitriles with sodium azide in solventless condition. The corresponding 5-substituted ^1H tetrazoles were obtained under... Zinc chloride is an efficient and safe catalyst in the [3 + 2] cycloaddition reaction of organic nitriles with sodium azide in solventless condition. The corresponding 5-substituted ^1H tetrazoles were obtained under mild conditions. This method can overcome disadvantages such as: the use of toxic metals and expensive reagents, drastic reaction conditions, water sensitivity and the presence of dangerous hydrazoic acid. 展开更多
关键词 5-Substituted ^1H-tetrazoles Zinc chloride Sodium azide solvent free
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Nonequilibrium Solvent Free Energy Curve from Molecular Theory in Electron Transfer Reaction
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作者 Jian XIJ Zheng YM ZHOU(Department of Chendstry, Qufu Normal University, Qufu, 273165)Ke Zhong ZHANG(Linyi Anucahon College, Linyi, 276000) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第5期439-442,共4页
The microscopic moleeular theory for electron transfer in a model solvent ishahr developed. The nonlinear response of the solvent molecules is be computedquanitatively in a new way. Adopting computer simulation daa an... The microscopic moleeular theory for electron transfer in a model solvent ishahr developed. The nonlinear response of the solvent molecules is be computedquanitatively in a new way. Adopting computer simulation daa and choosingappropriate reaction coordinae, a reasonable free energy dinram is constructed and thercorganhaion energy for the product state is calculated. 展开更多
关键词 free Nonequilibrium solvent free Energy Curve from Molecular Theory in Electron Transfer Reaction CM
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Solvent Free One-Pot Synthesis of 1,2,4,5-Tetrasubstituted Imidazoles Catalyzed by Secondary Amine Based Ionic Liquid and Defective Keggin Heteropoly Acid 被引量:3
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作者 Pranab Jyoti Das Jupitara Das +1 位作者 Munni Ghosh Sabera Sultana 《Green and Sustainable Chemistry》 2013年第4期6-13,共8页
Secondary amine based ionic liquid and defective Keggin type heteropoly acid (HPA) are separately used for efficient one-pot four-component synthesis of 1,2,4,5-tetrasubstituted imidazoles assisted by microwave (MW). ... Secondary amine based ionic liquid and defective Keggin type heteropoly acid (HPA) are separately used for efficient one-pot four-component synthesis of 1,2,4,5-tetrasubstituted imidazoles assisted by microwave (MW). Eco-friendly solvent free procedure, short reaction time, high yield of products and reusability of catalysts are important features of the synthesis. A comparative study on the efficiency of the two catalysts is reported. This work further demonstrates the alternate use of urea, instead of often used ammonium acetate, as source of nitrogen. 展开更多
关键词 Ionic Liquids KEGGIN HETEROPOLYACID Microwave Tetrasubstituted IMIDAZOLE solvent free Synthesis Multicomponent Reaction
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Montmorillonite K10 Clay Catalyzed One Pot Synthesis of 2,4,6-Tri Substituted Pyridine under Solvent Free Condition 被引量:1
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作者 Vellayan Kannan Krishnapillai Sreekumar 《Modern Research in Catalysis》 2013年第2期42-46,共5页
Montmorillonite K10 catalyzed synthesis of 2,4,6 triaryl pyridine under solvent free condition is described. Montmorillonite effectively catalyzed the reaction in good to excellent yields. Using this solid catalyst, t... Montmorillonite K10 catalyzed synthesis of 2,4,6 triaryl pyridine under solvent free condition is described. Montmorillonite effectively catalyzed the reaction in good to excellent yields. Using this solid catalyst, the reactions could be carried out in a short period of time with very good yield of triaryl pyridines, up to 97% under solvent free condition. This catalyst could be recycled very easily, which makes this methodology environmentally benign. The catalyst is active over three cycles. 展开更多
关键词 CLAY Catalyst solvent free Synthesis SUBSTITUTED PYRIDINE
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Ferric hydrogensulfate catalyzed aerobic oxidative coupling of 2-naphthols in water or under solvent free conditions
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作者 Hossein Eshghi Mehdi Bakavoli Hassanali Moradi 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第6期663-667,共5页
The symmetric oxidative coupling reactions of 2-naphthol derivatives with both ferric hydrogensulfate in water and silica ferric hydrogensulfate in solvent free conditions were carried out. The advantages of this gree... The symmetric oxidative coupling reactions of 2-naphthol derivatives with both ferric hydrogensulfate in water and silica ferric hydrogensulfate in solvent free conditions were carried out. The advantages of this green procedure are inexpensive catalyst or cocatalyst, reusability of catalyst, organic solvent-free procedures and simple workup. 展开更多
关键词 Silica ferric hydrogensulfate NAPHTHOL BINOL solvent-free
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L-Pyrrolidine-2-Carboxylic Acid Sulfate (LPCAS): A New Ionic Liquid for the Synthesis of 14-Aryl-14H-Dibenzo[a,j] Xanthenes under Solvent Free Condition
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作者 Vaibhav W. Godse Sahebrao S. Rindhe +2 位作者 Laszlo Kotai Pravin S. Kendrekar Rajendra P. Pawa 《International Journal of Organic Chemistry》 2017年第2期99-105,共7页
A new Bronsted acidic ionic liquid, L-Pyrrolidine-2-carboxylic acid sulfate (LPCAS) was employed to promote one-pot synthesis of 14-aryl-14H-dibenzo [a,j] xanthenes via condensation reaction of aldehydes and 2-naphtho... A new Bronsted acidic ionic liquid, L-Pyrrolidine-2-carboxylic acid sulfate (LPCAS) was employed to promote one-pot synthesis of 14-aryl-14H-dibenzo [a,j] xanthenes via condensation reaction of aldehydes and 2-naphthol under solvent free condition. Distinguishing features of the methodology are excellent yield of products in shorter reaction time, cleaner reaction profile, eco-friendly nature and the use of inexpensive catalyst. 展开更多
关键词 Ionic Liquid 14-Aryl-14H-Dibenzo[a j] XANTHENES solvent-free
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Fast Determination of Essential Oil from Dried Menthol Mint and Orange Peel by Solvent Free Microwave Extraction Using Carbonyl Iron Powder as the Microwave Absorption Medium 被引量:3
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作者 汪子明 丁兰 +4 位作者 王璐 封瑾 李铁纯 周新 张寒琦 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2006年第5期649-652,共4页
An improved solvent free microwave extraction, in which a kind of microwave absorption medium (carbonyl iron powder) was used, was applied to the extraction of essential oil from dried menthol mint and orange peel w... An improved solvent free microwave extraction, in which a kind of microwave absorption medium (carbonyl iron powder) was used, was applied to the extraction of essential oil from dried menthol mint and orange peel without addition of any solvent and pretreatment. It took much less time of extraction (30 min) than microwave-assisted hydrodistillation (90 min) and conventional hydrodistillation (180 min). The kinds of chemical compositions in essential oil extracted by different methods were almost the same and such improved solvent free microwave extraction can be a feasible way in extraction of essential oil from dried plant materials. 展开更多
关键词 solvent free microwave extraction essential oil menthol mint orange peel carbonyl iron powder
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A Facile Synthesis of Benzo[h]quinolines via Silica-TsOH-P2O5 Promoted Condensation of 1-Naphthylamines with 1,3-Diketones under Solvent Free Conditions 被引量:1
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作者 Chuanlei Zhu Ruiqiang Guo +2 位作者 Zhe Sheng Yanzhe Li Changhu Chu 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2017年第10期1595-1600,共6页
A facile synthesis of benzo[h]quinolines has been developed via improved Combes reaction. A combination of silica gel, p-toluenesulfonic acid and phosphorus pentoxide was utilized to promote the condensation of 1-naph... A facile synthesis of benzo[h]quinolines has been developed via improved Combes reaction. A combination of silica gel, p-toluenesulfonic acid and phosphorus pentoxide was utilized to promote the condensation of 1-naphthylamines with 1,3-diketones under solvent free conditions. In this case, silica gel was used as reaction media, p-toluenesulfonic acid and phosphorus pentoxide were acted as catalyst and dehydrating agent, respectively. 展开更多
关键词 silica-TsOH-P2O5 benzo[h]quinoline catalysis synthesis solvent free
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Synthesis of hexacyclic fused isocoumarin framework through selective domino multicyclizations under catalyst and solvent free conditions 被引量:1
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作者 Tariq Mahmood Babar Muhammad Moazzam Naseer +3 位作者 Muhammad Khawar Rauf Humayun Pervez Masahiro Ebihara Nasim Hasan Rama 《Chinese Chemical Letters》 SCIE CAS CSCD 2014年第9期1282-1286,共5页
A novel fused isocoumarin skeleton has been synthesized through selective domino multicyclizations by mixing homothallic acid and 2,3-diphenylacryloyl chloride at 200℃ under catalyst and solvent free reaction conditi... A novel fused isocoumarin skeleton has been synthesized through selective domino multicyclizations by mixing homothallic acid and 2,3-diphenylacryloyl chloride at 200℃ under catalyst and solvent free reaction conditions. Six fused rings with two stereogenic centers were assembled in a convenient onepot operation in good yield. The resulting hexacyclic fused isocoumarin skeleton and its stereochemistry was fully characterized and unambiguously confirmed by X-ray diffraction analysis. 展开更多
关键词 Hexacyclic Fused isocoumarin One pot Catalyst and solvent free
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An efficient synthesis of pyrazole chalcones under solvent free conditions at room temperature 被引量:1
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作者 Parvin Kumar Sunil Kumar +1 位作者 Khalid Husain Ashwani Kumar 《Chinese Chemical Letters》 SCIE CAS CSCD 2011年第1期37-40,共4页
An easy, safe, solvent free and effective method for the synthesis of pyrazole-substituted chalcones has been achieved by grinding pyrazole aldehydes and acetophenones in the presence of activated barium hydroxide (C... An easy, safe, solvent free and effective method for the synthesis of pyrazole-substituted chalcones has been achieved by grinding pyrazole aldehydes and acetophenones in the presence of activated barium hydroxide (C-200) in high yield within short span of time. All reactions were carried out just by grinding the two reactants in the presence of activated barium hydroxide (C-200). Results are also compared with sodium hydroxide and potassium hydroxide. 展开更多
关键词 Pyrazole aldehydes CHALCONES Activated barium hydroxide (C-200) solvent free conditions
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Microwave-enhanced Mannich Condensation of Terminal Alkynes, Primary Amines with Paraformaldehyde on Cuprous Iodide Doped Alumina under Solvent Free Conditions
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作者 王磊 李品华 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2003年第6期710-713,共4页
A microwave enhanced, solventless Mannich condensation of terminal alkynes, primary amines with paraformaldehyde on cuprous iodide doped alumina has been investigated. The structures of products depend on the ratio o... A microwave enhanced, solventless Mannich condensation of terminal alkynes, primary amines with paraformaldehyde on cuprous iodide doped alumina has been investigated. The structures of products depend on the ratio of alkyne to amine and paraformaldehyde. 展开更多
关键词 Mannich condensation terminal alkyne para^form^aldehyde primary amine cuprous iodide ALUMINA solvent free microwave irradiation
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Amide Hydrolysis Reaction Catalyzed by KF/Al2O3 under Microwave Irradiation and Solvent Free Conditions
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作者 张袖丽 罗凯 +1 位作者 陈巍 王磊 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2011年第10期2209-2212,共4页
A microwave-enhanced hydrolysis of amides utilizing KF/Al2O3 in the absence of solvents has been developed. Amines are produced in excellent yields along with the corresponding carboxylic acids.
关键词 AMIDE HYDROLYSIS KF/AL2O3 microwave irradiation solvent free AMINE
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Practical reduction of imines by NaBH_4/alumina under solvent-free conditions:An efficient route to secondary amine
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作者 Foad Kazemi Ali Reza Kiasat Ebrahim Sarvestani 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第10期1167-1170,共4页
Sodium borohydride supported on alumina reduces imines to the corresponding secondary amines in high to excellent isolated yields under solvent-free conditions. Noteworthy is that highly chemoselective reactions were ... Sodium borohydride supported on alumina reduces imines to the corresponding secondary amines in high to excellent isolated yields under solvent-free conditions. Noteworthy is that highly chemoselective reactions were achieved in the presence of other functional groups such as halogen, nitro, and cyano groups. 展开更多
关键词 IMINE Secondary amine solvent free REDUCTION Sodium borohydride
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Cu(OTf)2 Catalyzed Synthesis of Bis(5-methyl-2-furyl)methanes by Condensation of 2-Methylfuran with Carbonyl Compounds under Solvent Free Conditions
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作者 Muthyala, Manoj Kumar Rao, V. Kameswara Kumar, Anil 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2011年第7期1483-1488,共6页
A facile and efficient one-pot three-component synthesis of bis(5-methyl-2-furyl)methanes has been achieved via the reaction of 2-methylfuran with a series of aliphatic and aromatic aldehydes and aliphatic ketones i... A facile and efficient one-pot three-component synthesis of bis(5-methyl-2-furyl)methanes has been achieved via the reaction of 2-methylfuran with a series of aliphatic and aromatic aldehydes and aliphatic ketones in presence of copper(II) triflate under solvent free conditions. The bis(5-methyl-2-furyl)methanes were obtained in 34%--72% yields and the catalyst was recycled up to four successive cycles without much loss in catalytic activity. 展开更多
关键词 Lewis acid copper(II) triflate 2-METHYLFURAN bis(5-methyl-2-furyl)methane multicomponent condensation solvent free condition
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Sulfanilic acid catalyzed solvent-free synthesis of 1,5-benzodiazepine derivatives
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作者 Jaiprakash N.Sangshetti Nagnnath D.Kokare Devanand B.Shinde 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第11期1305-1308,共4页
Sulfanilic acid has been found to be an efficient catalyst for the synthesis of 1,5-benzodiazepines from o-phenylenediamine and ketones. This method is simple, effective and environmentally friendly and gives better y... Sulfanilic acid has been found to be an efficient catalyst for the synthesis of 1,5-benzodiazepines from o-phenylenediamine and ketones. This method is simple, effective and environmentally friendly and gives better yields. 展开更多
关键词 1 5-Benzodiazepines Sulfanilic acid catalyst solvent free condition
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Selective suppression of toluene formation in solvent-free benzyl alcohol oxidation using supported Pd-Ni bimetallic nanoparticles 被引量:8
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作者 Jianwei Che Mengjia Hao +4 位作者 Wuzhong Yi Hisayoshi Kobayashi Yuheng Zhou Liping Xiao Jie Fan 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第11期1870-1879,共10页
The solvent‐free oxidation of benzyl alcohol was studied using supported Pd‐Ni bimetallic nanoparticles.Compared with monometallic Pd,the addition of Ni to Pd was found to be effective in suppressing the nondesired ... The solvent‐free oxidation of benzyl alcohol was studied using supported Pd‐Ni bimetallic nanoparticles.Compared with monometallic Pd,the addition of Ni to Pd was found to be effective in suppressing the nondesired product toluene,thereby enhancing the selectivity towards benzaldehyde.This result was attributed to a dual effect of Ni addition:the weakening of dissociative adsorption of benzyl alcohol and the promotion of oxygen species involved in the oxidation pathway. 展开更多
关键词 Palladium‐nickel Bimetallic nanoparticle Benzyl alcohol TOLUENE solventfree Oxidation
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Microwave-assisted synthesis of asymmetric thiocarbonohydrazones under solvent-free conditions 被引量:5
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作者 Qing Han Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第7期793-796,共4页
Six new asymmetric thiocarbonohydrazones 3a-3f were synthesized from following steps: firstly hydrazine hydrate reacted with carbon disulfide to form thiocarbonohydrazide (1) under microwave irradiation. Then compo... Six new asymmetric thiocarbonohydrazones 3a-3f were synthesized from following steps: firstly hydrazine hydrate reacted with carbon disulfide to form thiocarbonohydrazide (1) under microwave irradiation. Then compound (1) reacted with ketone and different aldehydes step by step to give 3a-3f with excellent yields under solvent-free conditions using microwave irradiation. Their structures have been determined by elemental analysis, IR, MS and ^1H NMR data. 2009 Qing Han Li. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved. 展开更多
关键词 Thiocarbonohydrazide Asymmetric thiocarbonohydrazones Microwave irradiation solvent-free Organic synthesis
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