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Synthesis of p-nitrophenol under normal pressure with A-1 phase transfer catalysis

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Journal of Central South University of Technology 2001年第1期8卷 54-56页

作者： ZHONG Shi an, OUYANG Xi, ZHOU Chun shan, CHENG Ben cheng (College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China) College of Chemistry and Chemical Engineering Central South University Changsha China

p nitrophenol is synthesized using p nitrochlorobenzene and sodium hydroxide with phase transfer catalyst. Several reaction factors, such as catalyst type, the amounts of catalysts and sodium hydroxide, the concentration of sodium hydroxide solution as well as reaction time, affect greatly the yield of p nitrophenol. The optimum reaction conditions are as follows: A 1 used as phase transfer catalyst whose consumption is 6% (mole fraction) of p nitrochlorobenzene; the molar ratio of sodium hydroxide to p nitrochlorobenzene is 3:1; the concentration of sodium hydroxide solution is 50% (mass fraction). Nitrobenzene, whose molar amount is 2.45 times as much as that of p nitrochlorobenzene; reaction time is 7 h at 140 ℃ under normal pressure. The final yield of p nitrophenol is 83.6%.

关键词： phase transfer catalysis p nitrophenol synthesis

One-pot Synthesis of 1-Aryloxyacety l-4-(4'-nitrophenyloxyacetyl)-thiosemicarbazides under phase transfer catalysis and Microwave Irradiation

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Chinese Chemical Letters 2002年第8期13卷 717-720页

作者： Zheng LI Xi Cun WANG College of Chemistry and Chemical Engineering Northwest Normal UniversityLanzhou 730070

The 1-aryloxyacetyl-4-(4-nitrophenyloxyacetyl)-thiosemicarbazides (3a-h) are synthe- sized via reaction of 4-nitrophenyloxyacetyl chloride with ammonium thiocyanate and aryloxyacetic hydrazides (2a-h) under phase tran... 详细信息

关键词： Diaryloxyacetyl thiosemicarbazide phase transfer catalysis microwave irradiation.

Efficient and Convenient Synthesis of Diethers from Furoin Under Ultrasound and Solid-liquid phase transfer catalysis Conditions

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Chemical Research in Chinese Universities 2007年第4期23卷 486-488页

作者： ZHANG Feng LI Ya-zhuo WANG Yun-xin GAO Da-wei SUN Ji-kui ZHANG Yu-min ZHAO Tian-qi CHEN Xiao-dong College of Chemistry Jilin University Changchun 130012 P. R. China Experimental Center of Testing Science Jilin University Changchun 130021 P. R. China

Compounds having an active hydroxy group, such as, acyloins can be easily alkylated by alkyl halides in the presence of a phase transfer catalyst （PTC）. The reaction is usually carried out in the presence of con-centrated aqueous sodium or potassium hydroxide and a phase transfer catalyst, such as, quaternary ammonium salts^[1-3] species, miscible which facilitate the interphase transfer of making reactions between reagents in two im-phases possible. The reaction involves a series of equilibrium and mass-transfer steps.

关键词： Ultrasound phase transfer catalysis Furoin O-Alkylation

Synthesis of diethers derived from furoin by phase transfer catalysis under microwave irradiation

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Chinese Chemical Letters 2007年第7期18卷 791-794页

作者： Feng Zhang Ya Zhuo Li Da Wei Gao Ji Kui Sun Yu Min Zhang College of Chemistry Jilin University Changchun Jilin 130012 China

A series of new diethers were obtained by alkylation of furoin under microwave irradiation （MWI） in phase transfer catalysis （PTC） conditions. The products of alkyl halides were synthesized in good yields （〉75%） within a few minutes, and the products of dihalides were synthesized in fair yields （about 45%）. The yields are dramatically improved compared to conventional heating under the same conditions, in spite of similar profiles of rising in temperature.

关键词： Microwave irradiation Furoin phase transfer catalysis O-Alkylation

Visible light-promoted enantioselective aerobic oxidation of pyrazolones by phase transfer catalysis

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Green Synthesis and catalysis 2022年第1期3卷 102-109页

作者： Yakun Wang Shuaifei Wang Jie Liu Mingming Lian Yifan Chen Ke Wang Yawei Zhang Tao Zhang Lizhen Fang School of Pharmacy Xinxiang Medical UniversityXinxiang 453003China Department of Pharmaceutics Daqing CampusHarbin Medical UniversityDaqing 163319China School of Medical Engineering Xinxiang Medical UniversityXinjiang 453003China

An efficient and enantioselective aerobic oxidation of 4-substituted pyrazolones has been developed by phase transfer *** visible light as the driving force and O_(2)(in air)as the oxidant,broad scopes(38 examples)of pyrazolones bearing an oxygen-attached carbon stereocenter at C-4 position were obtained in high yields(up to 98%)and excellent enantioselectivities(up to 93%ee)under mid *** ready availability of catalyst,ease of operation,and low-cost and eco-friendly nature highlighted the practical utility of this visible lightpromoted enantioselective aerobic oxidation.

关键词： Aerobic oxidation Pyrazolone Visible light phase transfer catalysis Cinchona alkaloid

An Efficient Synthesis of Polymethylene-bis-aroyl Thiourea Derivatives under the Condition of phase transfer catalysis

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Chemical Research in Chinese Universities 2001年第Z1期17卷 194-195页

作者： WEI TaiBao Department of Chemistry Northwest Normal University

A number of 1,3-disubstituted derivatives are associated with various types of biological activity [1]. Some thioureas are useful as herbicides, insecticides and plant-growth regulators. Treatment of acylisothiocyanates, prepared from aroyl chlorides (0.0431mol) and potassium thiocyanate (33ml ofa 33% KSCN solution) using tetrabutylammonium bromides as a catalyst, were treated with aniline to yield the corresponding thioureas. However, probable hydrolysis of the aroyl chlorides led to decreased yields. The reaction of acid chlorides with different phenylthioureas or N1-acetyl-N3-arylthioureas requires high temperature and long reaction times. None of the other reported methods proved satisfactory. As a continuation of our earlier work on the biological activity of these compounds, [2-5] we now report acid chlorides are quantitatively converted to the acylisothiocyanates under solid-liquid phase-transfer conditions using PEG-400 as the catalyst. Treatment of these isothiocyanates with polymethylenediamines provides compounds 3 in high yields (scheme 1). The results were summarized in table 1.

关键词： phase transfer catalysis Thiourea Derivatives biological activity acid chlorides high temperature

Synthesis of n-Butyl Acetate by Microwave Irradiation Under the Assistance of Solid-Liquid phase transfer catalysis Without Solvent

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Chemical Research in Chinese Universities 1992年第3期8卷 324-326页

作者： XU Wen-guo, LIU Fu-an, YU Ai-min, LI Yao-xian, JIN Shen-xi,LIU Jun and JIN Qin-han (Department of Chemistry, Jilin University, Changchun, 130023)

Introduction Microwave irradiation has been very widely used in heating, cooking and brewing. Several papers which describe the use of domestic microwave ovens to perform rapid organic synthesis in solution have been published. The high heating efficiency gives rise to remarkable rate of reaction and dramatic reduction of reaction time. Nevertheless, its application seems to be limited to these procedures because of

关键词： Microwave irradiation phase transfer catalysis Synthesis n-Butyl ace-tate Inorganic support

Novel Bis-(N-alkyl-N ,N-dimethyl-ammonium) Polyethyleneglycol Ether Salts as phase transfer Catalysts in the Condensation of l,4-Diacetyl-2,5-piperazinedione and Aldehydes

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Chemical Research in Chinese Universities 1995年第2期11卷 178-184页

作者： WANG Li-xin,XU Ming-hua,SHI Yao-zcng and HU Hong-wen (Department of Chemistry,Nanjing University,Nanjing,210008) resent address Chengdu Institute of Organic Chemistry,Acdemia Sinica,Chengdu,610015 Present address:Chengdu lnstutute of Organic Chentistry Acdemia Simca.Chengdu,G10015 NANJING UNIV DEPT CHEMNANJING 210008PEOPLES R CHINA

phase transfer catalysis (PTC) has become one of the most extensively used techniques in organic synthesis. The key factor in such processes is the catalyst. There are mainly two kinds of phase transfer catalysts, one is the so called "crown ethers" including macrocyeles, open chain molecules with long chains, bearing heteroatoms at a proper distance, and can chelate inorganic

关键词： phase transfer catalysis 2 5-Piperazincdione Selectivity

Synthesis and in vitro Antibacterial Activities of 5-（2,3,4,5- Tetrahydro-1 H-chromeno[2,3-dJpyrimidin-5-yl）pyrimidione Derivatives

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Chinese Journal of Chemistry 2012年第2期30卷 386-390页

作者： Cheng,Qingfang Wang,Qifa Tan,Ting Wang,Mingxiao Chen,Na Department of Chemical Technology Huaihai Institute of TechnologyLianyungangJiangsu 222005China Jiangsu Key Laboratory of Marine Biotechnology Huaihai Institute of TechnologyLianyungangJiangsu 222005China

A series of novel 5-（2,3,4,5-tetrahydro-lH-chromeno[2,3-d]pyrimidin-5-yl）pyrimidione derivatives have been synthesized from substituted salicylaldehydes and barbituric acid or 2-thiobarbituric acid in water catalyzed by phase transfer catalysis of triethylbenzyl ammonium chloride （TEBA）. Elemental analysis, IR, 1HNMR, and 13C NMR elucidated the structures of all the newly synthesized compounds. In vitro antimicrobial activities of synthesized compounds have been investigated against Escherichia coli, Bacillus subtilis, Staphylococcus aureus, and Pseudornonas aeruginosa. These newly synthesized derivatives exhibited significant in vitro antibacterial activity.

关键词： 5-(2,3,4,5-tetrahydro-lH-chromeno[2,3-d]pyrimidin-5-yl)pyrimidione antibacterial activity phase transfer catalysis water