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Potassium iodide catalyzed reductive dehalogenation ofα-halo-ketones using Hantzsch ester diethyl 1,4-dihydro-2,6-dimethylpyridine-3,5-dicarboxylate as reductant 被引量:1
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作者 Hong Sheng Li Yi Qun Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第8期931-934,共4页
In the presence of diethyl 1,4-dihydro-2,6-dimethylpyridine-3,5-dicarboxylate(DHP) and a catalytic amount of potassium iodide,severalα-halo ketones were easily reduced to the corresponding ketones in acetone media.... In the presence of diethyl 1,4-dihydro-2,6-dimethylpyridine-3,5-dicarboxylate(DHP) and a catalytic amount of potassium iodide,severalα-halo ketones were easily reduced to the corresponding ketones in acetone media.The procedure presented here showed several merits such as short reaction time,practical experimental and isolated procedure,and excellent yields of products. 展开更多
关键词 DEHALOGENATION α-halo ketones Hantzsch ester 1 4-Dihydro-2 6-dimethylpyridine-3 5-dicarboxylate Potassium iodide
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Copper-Catalyzed C-C(O)C Bond Cleavage of Monoalkylated β-Diketone: Synthesis of α,β-Unsaturated Ketones
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作者 Tony Wheellyam Pouambeka Victor N’goka +3 位作者 Narcisse Nicaise Obaya Guy Crépin Enoua Hubert Makomo Qian Zhan 《International Journal of Organic Chemistry》 2023年第2期41-49,共9页
A new and simple route for the synthesis of α,β-unsaturated ketones via cleavage of the C-C(O)C single bond of monoalkylated β-diketone has been described. The reaction was catalyzed by copper, a cheap transition m... A new and simple route for the synthesis of α,β-unsaturated ketones via cleavage of the C-C(O)C single bond of monoalkylated β-diketone has been described. The reaction was catalyzed by copper, a cheap transition metal in a weakly basic medium (K<sub>3</sub>PO<sub>4</sub>) at room temperature. To carry out this study, we first had to synthesize the monoalkylated β-diketones 1. Afterwards, α,β-unsaturated ketones 2 were obtained with high yields around 80%. Finally, all the products were characterized by 1H NMR, 13C NMR, and HRMS spectra. . 展开更多
关键词 Monoalkylated β-diketone α β-Unsaturated ketones COPPER-CATALYZED C-C(O)C Bond Cleavage
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Chemoselective synthesis of novel aminoindolizines using aminopyridines, acetylenic diesters and α-halo ketones
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作者 Sakineh Asghari Mohammad Qandalee +2 位作者 Vahideh Behboodi Arastoo Nouri Gorji Ghasem Firouzzade Pash 《Chinese Chemical Letters》 SCIE CAS CSCD 2016年第3期361-364,共4页
A chemoselective synthesis of novel indolizine derivatives were reported via three-component reactions of aminopyridines, acetylenic diesters and a-halo ketones. In these reactions, the zwitterion generated from amino... A chemoselective synthesis of novel indolizine derivatives were reported via three-component reactions of aminopyridines, acetylenic diesters and a-halo ketones. In these reactions, the zwitterion generated from aminopyridines and acetylenic diesters reacted with a-halo ketones to produce indolizine skeleton in good to high yields under mild reaction conditions. 展开更多
关键词 Aminopyridines a-halo ketones Acetylenic diesters Indolizine Chemoselective synthesis
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Direct oxidation of the C_(sp3)-H bonds of N-heterocyclic compounds to give the corresponding ketones using a reusable heterogeneous MnO_x-N@C catalyst 被引量:2
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作者 任兰会 王连月 +2 位作者 吕迎 李国松 高爽 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第8期1216-1221,共6页
Novel reusable MnOx‐N@C catalyst has been developed for the direct oxidation of N‐heterocycles under solvent‐free conditions using TBHP as benign oxidant to give the corresponding N‐heterocyclic ketones. The catal... Novel reusable MnOx‐N@C catalyst has been developed for the direct oxidation of N‐heterocycles under solvent‐free conditions using TBHP as benign oxidant to give the corresponding N‐heterocyclic ketones. The catalytic system exhibited a broad substrate scope and excellent regi‐oselectivity, as well as being amenable to gram‐scale synthesis. This MnOx‐N@C catalyst also showed good reusability and was successfully recycled six times without any significant loss of activity. 展开更多
关键词 Oxidation Heterogeneous catalyst ketonE C-H bond Manganese
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CeCl_3·7H_2O as an efficient catalyst for one-pot synthesis of β-amino ketones by three-component Mannich reaction 被引量:10
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作者 Yan Dai Chun Xu Lü 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第1期31-34,共4页
Cerium trichloride heptahydrate(CeCl_3·7H_2O) was found to be an efficient and recyclable catalyst for the three-component direct Mannich reaction of anilines and benzaldehydes with acetophenone.This protocol has... Cerium trichloride heptahydrate(CeCl_3·7H_2O) was found to be an efficient and recyclable catalyst for the three-component direct Mannich reaction of anilines and benzaldehydes with acetophenone.This protocol has advantages of high yield,no environmental pollution,mild condition,and simple work-up procedure. 展开更多
关键词 Cerium trichloride heptahydrate Mannich reaction β-Amino ketones Lewis acid
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Gallium trichloride-catalyzed conjugate addition of indole and pyrrole to α,β-unsaturated ketones in aqueous media 被引量:5
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作者 Rong Xu Jin Chang Ding +2 位作者 Xi An Chen Miao Chang Liu Hua Yue Wu 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第6期676-679,共4页
Michael addition of indole and pyrrole to a variety of α, β-unsaturated ketones was efficiently promoted by a catalytic amount of GaCl3 in aqueous media to afford the corresponding products in good to excellent yields.
关键词 Gallium trichloride Michael addition INDOLE PYRROLE α β-Unsaturated ketones
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Ambient Ionic Liquids Used in the Reduction of Aldehydes and Ketones 被引量:3
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作者 DanQianXU ShuPingLUO BaoYouLIU ZhenYuanXU YinChuSHEN 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第6期643-645,共3页
The sodium borohydride reduction of aldehydes and ketones to corresponding alcohols has been accomplished via the use of ionic liquids. The alcohols are easily obtained with excellent yields and the ionic liquid BMImB... The sodium borohydride reduction of aldehydes and ketones to corresponding alcohols has been accomplished via the use of ionic liquids. The alcohols are easily obtained with excellent yields and the ionic liquid BMImBF4 could be reused. 展开更多
关键词 Ionic liquids sodium borohydride REDUCTION ALDEHYDE ketone.
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A simple and efficient method for solvent-free iodination of hydroxylated aromatic aldehydes and ketones using iodine and iodic acid by grinding method 被引量:3
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作者 Archana Vibhute Shyam Mokle +2 位作者 Khushal Karamunge Vasant Gurav Yeshwant Vibhute 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第8期914-918,共5页
Green,mild and efficient iodination of hydroxylated aromatic aldehydes and ketones using iodine and iodic acid in the solidstate by grinding under solvent-free conditions at room temperature.This method provides sever... Green,mild and efficient iodination of hydroxylated aromatic aldehydes and ketones using iodine and iodic acid in the solidstate by grinding under solvent-free conditions at room temperature.This method provides several advantages such as environmentally friendly,short reaction times,high yields,non-hazardous and simple work-up procedure. 展开更多
关键词 IODINATION Aromatic aldehydes Aromatic ketones GRINDING
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Baeyer-Villiger oxidation of cyclic ketones utilizing potassium peroxydisulfate(K_2S_2O_8) or sodium perborate(NaBO_3) in acidic media 被引量:8
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作者 S.Zarrabi N.O.Mahmoodi +1 位作者 K.Tabatabaeian M.A.Zanjanchi 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第12期1400-1404,共5页
The efficient, green, facile, mild and straightforward conversion procedure for the oxidation of cyclic ketones to lactones at room temperature utilizing potassium peroxydisulfate (K2S2O8) in acidic media is satisfa... The efficient, green, facile, mild and straightforward conversion procedure for the oxidation of cyclic ketones to lactones at room temperature utilizing potassium peroxydisulfate (K2S2O8) in acidic media is satisfactory to high yields without using traditional chlorinated solvents is reported. This oxidative reagent is cheap and friendly environmental procedure for industrial purposes than use of organic peracids. 展开更多
关键词 Baeyer-Villiger oxidation Cyclic ketones Potassium peroxydisulfate (K2S208) Acidic media Sodium perborate (NaBO3)
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Novel Chiral PNNP-Ru Complexes:Synthesis and Application in Asymmetric Transfer Hydrogenation of Ketones 被引量:3
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作者 CHENG Zhi-box YU Shen-luan +4 位作者 LI Yan-yun DONG Zhen-rong SUN Guo-song HUANG Ke-lin GAO Jing-xing 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第2期170-173,共4页
The efficient catalytic systems generated in situ from RuCl2(PPh3)3 and chiral ligands N,N-bis[2-(di-o-tolylphosphino)-benzyl]cyclohexane-1,2-diamine(2) were employed for asymmetric transfer hydrogenation of aro... The efficient catalytic systems generated in situ from RuCl2(PPh3)3 and chiral ligands N,N-bis[2-(di-o-tolylphosphino)-benzyl]cyclohexane-1,2-diamine(2) were employed for asymmetric transfer hydrogenation of aromatic ketones, giving the corresponding optically active alcohols with high activities(up to 99% conversion) and excellent enantioselectivities(up to 96% e.e.) under mild conditions. The chiral ruthenium(Ⅱ) complex (R,R)-3 has been prepared and characterized by NMR and X-ray crystallography. 展开更多
关键词 Chiral PNNP ligand Ru complex Asymmetric transfer hydrogenation Aromatic ketone
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Synthesis of α,β-Unsaturated Ketones using Potassium fluoridealumina Catalyst by Microwave Irradiation 被引量:4
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作者 Xiao Hui ZHANG Da Bin GAO +1 位作者 Ming GUO Shan Zhen YAN(Department of Chendstry and Chemical Engineering, Dalian University, Dalian 116622) 《Chinese Chemical Letters》 SCIE CAS CSCD 1998年第6期521-522,共2页
Microwave irradiation can accelerate the rate of the synthetic reaction of α,β-unsaturated ketones by using KF-Al2O3 as catalyst. The rate enhancement of the reaction is 360-860 fold.
关键词 Microwave irradiation α β-unsaturated ketone KF-Al_2O_3
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Baeyer-Villiger oxidation of ketones with hydrogen peroxide catalyzed by Sn-aniline complex 被引量:2
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作者 Qing Hua Zhang Shou Feng Wang Zi Qiang Lei 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第1期4-6,共3页
Sn-aniline complex was prepared by a simple procedure. Cyclic and acyclic ketones were oxidized into lactones or esters with very high selectivity and yield with 30% hydrogen peroxide in the presence of Sn-aniline com... Sn-aniline complex was prepared by a simple procedure. Cyclic and acyclic ketones were oxidized into lactones or esters with very high selectivity and yield with 30% hydrogen peroxide in the presence of Sn-aniline complex. 展开更多
关键词 Baeyer-Villiger oxidation Sn-aniline complex ketone oxidation Hydrogen peroxide
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Alkoxy substituted MeO-BIPHEP-type diphosphines ligands for asymmetric hydrogenation of aryl ketones 被引量:2
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作者 Meng Lin Ma Zong Hai Peng +3 位作者 Yu Guo Li Chen Hua Chen Xian Jun Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第5期576-579,共4页
In this paper,a series of optically active MeO-BIPHEP-type ligands,(S)-6,6′-dimethoxy-2,2’-bis(di-p-alkoxyphenylphosphine)- 1,1′-biphenyl were synthesized and used to prepare the ruthenium complex.The effects o... In this paper,a series of optically active MeO-BIPHEP-type ligands,(S)-6,6′-dimethoxy-2,2’-bis(di-p-alkoxyphenylphosphine)- 1,1′-biphenyl were synthesized and used to prepare the ruthenium complex.The effects of para-substituted were observed,the results showed that the ruthenium catalysts[diphosphine RuCl;diamine]containing both t-Bu and i-Pr substitutions have better activities and enantioselectivities than the non-substituted ruthenium catalysts in the asymmetric hydrogenation of acetophenone. 展开更多
关键词 Aryl ketone Asymmetric hydrogenation Biaryl phosphines ligands Ruthenium complex
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Triphenylphosphine-catalyzed isomerization of alkynyl ketones in aqueous solution 被引量:1
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作者 Qing Fa Zhou Fei Yang +1 位作者 Qing Xiang Guo Song Xue 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第9期1029-1032,共4页
An efficient isomerization of alkynyl ketones to (E,E)-diene ketones was developed. The reaction catalyzed by 20 mol% triphenylphosphine in aqueous media gave the desired products in good yields.
关键词 TRIPHENYLPHOSPHINE ISOMERIZATION Alkynyl ketones Water
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Convenient Asymmetric Borane Reduction of Ketones Catalyzed by Simple Amino Alcohols and Corresponding Amino Acids 被引量:1
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作者 Guo Bin SUN Wei Wei PEI +1 位作者 Hui WANG Wei Ping YE 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第12期1147-1148,共2页
An asymmetric borane reduction of prochiral ketones catalyzed by simple amino alcohols and corresponding amino acids was examined to give alcohols with e.e. value up to 92% .
关键词 Enantioselective borane reduction amino alcohols amino acids ketones.
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TRANSFER HYDROGENATION OF KETONES BY PROPAN-2-OL OVER POLY(PHENYLENE OXIDE) ANCHORED RUTBENIUM CATALYST 被引量:1
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作者 Han Rong GAO Yun XU Shi Jian LIAO and Dao Rong YU(Dalina Institute of Chemical Physics,Chinese Acaemy of Sciences,Dalian 116023)(Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences ,Shanghai 20003 《Chinese Chemical Letters》 SCIE CAS CSCD 1994年第3期189-192,共4页
Both aliphatic and aromatic ketones are efficiently transfer-hydrogenated by propan-2-ol under mild conditions in the presence of a catalytic amount of poly(2,6-dimethyl-1,4-Phenylene oxide) (PPO) anchored ruthenium... Both aliphatic and aromatic ketones are efficiently transfer-hydrogenated by propan-2-ol under mild conditions in the presence of a catalytic amount of poly(2,6-dimethyl-1,4-Phenylene oxide) (PPO) anchored ruthenium complex and sodium hydroxide. An important feature of this polymer anchored catalyst is its stability in air. 展开更多
关键词 OL OVER PROPAN PHENYLENE ketones ANCHORED BY
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Oxidation of benzyl alcohols to ketones and aldehydes by O3 process enhanced using high-gravity technology 被引量:1
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作者 Wenqiang Gao Lei Du +1 位作者 Weizhou Jiao Youzhi Liu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第3期808-814,共7页
In this study,a practical process for ozonization of benzyl alcohols to ketones and aldehydes in a rotating packed bed(RPB-O3)reactor has been developed.Using 1-phenylethanol as a model reactant,the performance of RPB... In this study,a practical process for ozonization of benzyl alcohols to ketones and aldehydes in a rotating packed bed(RPB-O3)reactor has been developed.Using 1-phenylethanol as a model reactant,the performance of RPB-O3 process in different solvents has been compared with the commonly used stirred tank reactor(STR-O3).Ethyl acetate was the optimum solvent for the conversion of 1-phenylenthanol to acetophenone in RPB-O3 process,with 78%yield after 30 min.In a parallel STR-O3 experiment,the yield of acetophenone was50%.Other experimental variables,i.e.O3 concentration,reaction time,high-gravity factor and liquid flow rate were also optimized.The highest yield of acetophenone was obtained using O3 concentration of 80 mg·L-1,reaction time of 30 min,high gravity factor of 40 and liquid flow rate of 120 L·h-1.Under the optimized reaction conditions,a series of structurally diverse primary and secondary alcohols was oxidized with(19%–92%)yield.The ozonization mechanism was studied by Electron Paramagnetic Resonance(EPR)spectroscopy,monitoring the radical species formed upon self-decomposition of O3.The characteristic quadruple peak with the 1:2:2:1 intensity ratio that corresponds to hydroxyl radicals(·OH)was observed in the electron paramagnetic resonance(EPR)spectrum,indicating an indirect oxidation mechanism of alcohols via·OH radical. 展开更多
关键词 OZONE Benzyl alcohols Aldehydes and ketones High-gravity technology
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Silicotungstic Acid Modified Bentonite: An Efficient Catalyst for Synthesis of Acetal Derivatives of Aldehydes and Ketones 被引量:1
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作者 Reshu Chaudhary Monika Datta 《Journal of Analytical Sciences, Methods and Instrumentation》 2013年第4期193-201,共9页
Acetals and ketals are among the important materials of organic synthesis and as protecting agent of carbonyl functionality. A milder, efficient and green synthesis of acetals and ketals has been developed using Silic... Acetals and ketals are among the important materials of organic synthesis and as protecting agent of carbonyl functionality. A milder, efficient and green synthesis of acetals and ketals has been developed using Silicotungstic acid modified Bentonite (STA-Ben) as a catalyst. STA-Ben has been synthesized and characterized by various analytical techniques. It has been found to be an efficient and reusable catalyst for the synthesis of acetyl derivatives in excellent yields. In order to elucidate the efficiency of the STA-Ben as catalyst, reaction has also been performed using various catalysts. The reaction conditions (time and amount of catalyst) have been optimized using various catalysts. The products of the various reactions have been characterized by FT-IR, NMR. 展开更多
关键词 Silicotungstic ACID BENTONITE ALDEHYDES ketones
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Sm/TiCl_4 (cat.) system-mediated intermolecular and intramolecular reductive coupling reactions of ketones with esters 被引量:1
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作者 LIU Yun-kui XU Dan-qian +1 位作者 XU Zhen-yuan ZHANG Yong-min 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第7期999-1003,共5页
Sm/TiCl4 system could well integrate the high reactivity of samarium(Ⅱ) and high deoxygenation capacity of low valent titanium within one system. In this paper, the intermolecular and intramolecular reductive coupl... Sm/TiCl4 system could well integrate the high reactivity of samarium(Ⅱ) and high deoxygenation capacity of low valent titanium within one system. In this paper, the intermolecular and intramolecular reductive coupling reactions of ketones with esters mediated by metallic samarium (Sm) and a catalytic amount of titanium tetrachloride (TiCl4) were successfully developed. A series of substituted ketones and cyclic β-keto-esters were prepared in moderate to good yields under reflux and neutral conditions. 展开更多
关键词 Samarium (Sm) Titanium tetrachloride (TiCl4) ketone Ester Reductive coupling reaction
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A Practical and Efficient Procedure for Preparation of Diacetals from 2,2-Bis(hydroxymethyl) propane-1,3-diol with Aldehydes and Ketones Catalysed by Anhydrous Ferrous Sulfate 被引量:6
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《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第S1期285-285,共1页
关键词 A Practical and Efficient Procedure for Preparation of Diacetals from 2 2-Bis HYDROXYMETHYL propane-1 3-diol with Aldehydes and ketones Catalysed by Anhydrous Ferrous Sulfate
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