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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 Catalytic Hydrogenation of α,β-Unsaturated Ketones and α,β-Unsaturated Carboxylic Esters
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作者 ZHANG Jing-wen ZHAO Jian-zhang +6 位作者 ZHANG Xiao-long JIANG Yu-lin MA Xiu-li SUN Yun-xiu JIANG Wen-pu LI Yao-xian XU Zhi-luo 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1998年第2期17-22,共6页
The effect of catalysts P-2 00-Ni(Nickel boride) and P-2 00-Ni-M(M: Co, Fe, Cu, Sn), prepared by adopting a modified recipe, on the chemoselective hydrogenation of carbon carbon double bonds in α,β- unsaturated... The effect of catalysts P-2 00-Ni(Nickel boride) and P-2 00-Ni-M(M: Co, Fe, Cu, Sn), prepared by adopting a modified recipe, on the chemoselective hydrogenation of carbon carbon double bonds in α,β- unsaturated ketones, and the activity of catalysts P-1.80-Ni, P-2 00-Ni or P-1.80(2 00) -Ni-M(M: Pd, Co, Cu) in the selective hydrogenation of carbon carbon double bonds in α,β-unsaturated carboxylic esters, were investigated systematically. According to the experimental results, the selectivities of these catalysts toward the hydrogenation of the carbon carbon double bonds of α,β-unsaturated keones or α,β-unsaturated carboxylic esters are 96%—100% or 100%, respectively. 展开更多
关键词 α β-unsaturated ketone Nickel boride α β-unsaturated carboxylic ester
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Poly Ethylene Glycols as Efficient Media for the Synthesis of <i>β</i>-Nitro Styrenes from <i>α</i>, <i>β</i>-Unsaturated Carboxylic Acids and Metal Nitrates under Conventional and Non-Conventional Conditions
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作者 Kamatala Chinna Rajanna Kola Ramesh +3 位作者 Soma Ramgopal Somannagari Shylaja Pochampally Giridhar Reddy Pondichery Kuppuswamy Saiprakash 《Green and Sustainable Chemistry》 2011年第4期132-148,共17页
Poly ethylene glycols (PEG-200, 400, 600, 4000 and 6000) supported reactions were conducted with certain α, β-unsaturated acids in presence of metal nitrates under solvent free (solid state) and mineral acid free co... Poly ethylene glycols (PEG-200, 400, 600, 4000 and 6000) supported reactions were conducted with certain α, β-unsaturated acids in presence of metal nitrates under solvent free (solid state) and mineral acid free conditions. The reactants were ground in a mortar with a pestle for about 30 minutes. The aromatic acids underwent nitro decarboxylation and afforded β-nitro styrene derivatives in very good yield while α, β-unsaturated aliphatic carboxylic acids gave corresponding nitro derivatives. Addition of PEG accelerated rate of the reaction enormously. Reaction times substantially decreased from several hours to few minutes followed by highly significant increase in the product yield. Among the several PEGs PEG-300 has been found to be much more effective than other PEGs. 展开更多
关键词 Poly Ethylene Glycols (PEG) Rate Accelerations α β-unsaturated ACIDS Metal Nitrates Solvent Free (Solid State) β-Nitro Styrene DERIVATIVES β-unsaturated Aliphatic ACIDS NITRO DERIVATIVES
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Corrosion inhibition of α,β-unsaturated carbonyl compounds on steel in acid medium 被引量:5
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作者 Gao Jiancun Weng Yongji +2 位作者 Salitanate Feng Li Yue Hong 《Petroleum Science》 SCIE CAS CSCD 2009年第2期201-207,共7页
Corrosion inhibition of three α,β-unsaturated carbonyl compounds on N80 steel at high temperature and in concentrated acid medium was evaluated, and the inhibition mechanism was investigated. The results proved that... Corrosion inhibition of three α,β-unsaturated carbonyl compounds on N80 steel at high temperature and in concentrated acid medium was evaluated, and the inhibition mechanism was investigated. The results proved that both cinnamaldehyde and benzalacetone had an evident anticorrosion effect and could reduce the corrosion of steel effectively in acid medium, α,β-unsaturated carbonyl compounds with a benzene ring structure had good adsorption on steel surface. The experiments proved that polymerization of α,β-unsaturated carbonyl compounds on the steel surface at a high temperature and in concentrated acid medium resulted in a good corrosion inhibiting effect, which was attributed to the structures of α,β-unsaturated carbonyl compounds. 展开更多
关键词 α β-unsaturated carbonyl compounds corrosion inhibitor ADSORPTION oilfield acidizing treatment
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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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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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Two new α,β-unsaturated butyrolactone derivatives from Pleione bulbocodioides 被引量:2
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作者 Xin Qiao Liu Wen Yuan Gao +2 位作者 Yuan Qiang Guo Tie Jun Zhang Lu Lu Yan 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第9期1075-1077,共3页
Two new α,β-unsaturated butyrolactone derivatives, 4-(4″-hydroxybenzyl)-3-(3′-hydroxy-phenethyl)furan-2(5H)-one (1) and 3-(3′-hydroxyphenethyl)furan-2(5H)-one (2), together with one known phenolic compound (3), w... Two new α,β-unsaturated butyrolactone derivatives, 4-(4″-hydroxybenzyl)-3-(3′-hydroxy-phenethyl)furan-2(5H)-one (1) and 3-(3′-hydroxyphenethyl)furan-2(5H)-one (2), together with one known phenolic compound (3), were isolated from the tubers of Pleione bulbocodioides (Franch.) Rolfe. Their structures were elucidated by analysis of spectroscopic data. 展开更多
关键词 Pleione bulbocodioides α β-unsaturated butyrolactone Phenolic compound
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Methanol as hydrogen source: Chemoselective transfer hydrogenation of α,β-unsaturated ketones with a rhodacycle 被引量:1
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作者 Ahmed H. Aboo Robina Begum +2 位作者 Liangliang Zhao Zahoor H. Farooqi Jianliang Xiao 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第11期1795-1799,共5页
Methanol is a safe, economic and easy-to-handle hydrogen source. It has rarely been used in transfer hydrogenation reactions, however. We herein report that a cyclometalated rhodium complex, rhodacycle, catalyzes high... Methanol is a safe, economic and easy-to-handle hydrogen source. It has rarely been used in transfer hydrogenation reactions, however. We herein report that a cyclometalated rhodium complex, rhodacycle, catalyzes highly chemoselective hydrogenation of α,β-unsaturated ketones with methanol as the hydrogen source. A wide variety of chalcones, styryl methyl ketones and vinyl methyl ketones, including sterically demanding ones, were reduced to the saturated ketones in refluxing methanol in a short reaction time, with no need for inter gas protection, and no reduction of the carbonyl moieties was observed. The catalysis described provides a practically easy and operationally safe method for the reduction of olefinic bonds in α,β-unsaturated ketone compounds. 展开更多
关键词 α β-unsaturated ketones Transfer hydrogenation METHANOL Rhodium complex CHEMOSELECTIVITY
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A mild,simple and efficient method for selectiveα-monobromination of 1,3-diketones and β-ketoesters using pyridinium bromochromate 被引量:2
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作者 Yaghoub Sarrafi Marzieh Sadatshahabi Kamal Alimohammadi 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第4期393-396,共4页
Pyridinium bromochromate has been found to be a highly efficient and selective reagent for the α-monobromination of 1,3- diketones and β-keto-esters in the absence of base, Lewis acid, or other catalyst. The product... Pyridinium bromochromate has been found to be a highly efficient and selective reagent for the α-monobromination of 1,3- diketones and β-keto-esters in the absence of base, Lewis acid, or other catalyst. The products were formed in high to excellent yields under mild reaction conditions and in short reaction times. 展开更多
关键词 α-Monobromination β-ketoesters Pyridinium bromochromate 1 3-Diketones
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Nickel (Ⅱ) Complex Catalyzed Conjugate Addition Reaction of Functionalised Organozinc Reagents to α,β -Unsaturated Esters 被引量:1
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作者 Yu Lai HU Jian Hua YU +2 位作者 Shi Yan YANG Yuan Qi YIN Jin Xian WANG(State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics. Chinese Academy of Sciences, Lanzhou 730000)(Department of Chemistry, Northwest Normal U 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第1期17-18,共2页
Functionalized organozinc reagents can easily under 1, 4-addition reaction withunsaturated esters in the presence of catalytic amount of Ni (acac)_2 and tertiary ammes under verymild conditions to give the products in... Functionalized organozinc reagents can easily under 1, 4-addition reaction withunsaturated esters in the presence of catalytic amount of Ni (acac)_2 and tertiary ammes under verymild conditions to give the products in excellent yields. 展开更多
关键词 Conjugate addition reaction organozinc reagents α β-unsaturated esters nickel complex CATALYSIS
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Addition of Organosamarium Reagents toα, β-Unsaturated Esters
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作者 Yun Fa ZHENG Wei Liang BAO Yong Min ZHANG( Department of Chemistry, Zhejiang University, Xi Xi Campus, Hangzhou 310028 Li Shui Teachers College. Zhejiang 323000) 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第1期5-8,共4页
Allylsamarium bromide reacts with Q, 6 -unsaturated esters and a -alkyloxy carbonyl α, β-unsaturated esters to give l,2-addition and 1 .4-addition products respectively.
关键词 SAMARIUM Grignard reagent conjugate addition α β-unsaturated esters.
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Cyclization Reaction of α-Triazolyl-α, β-unsaturated Ketones with Phenyl hydrazine
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作者 Guo Feng ZHAO Jun REN +1 位作者 Yu Chang LI Gui Yu JIN (Institute of Elemento-Organic Chemistry, National Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071) 《Chinese Chemical Letters》 SCIE CAS CSCD 1998年第11期979-982,共4页
The reaction of α-triazolyl-α, β-unsaturated ketones with phenyl hydrazine was studied. The result indicated that cyclization took place and new heterocyclic compounds of substituted 4,5-2H-pyrazoles were obtained,... The reaction of α-triazolyl-α, β-unsaturated ketones with phenyl hydrazine was studied. The result indicated that cyclization took place and new heterocyclic compounds of substituted 4,5-2H-pyrazoles were obtained, whose structures and conformation were characterized by 1H NMR, IR, MS, elemental analysis and X-ray diffraction. 展开更多
关键词 α β-unsaturated ketones phenyl hydrazine TRIAZOLE CYCLIZATION PYRAZOLES
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Stereoselective Addition of N-Alkylhydroxylamines to α,β-Unsaturated Nitro Compounds
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作者 Ai Jun LI Ji Cheng CHU +2 位作者 Hong Sheng GUO Xue Qin ZHOU Dong Zhi LIU 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第7期859-862,共4页
N-Alkylhydroxylamines have been shown to undergo a stereospecific cis addition to 1-phenyl-2 -nitropropene compounds, whereas the corresponding O-alkylhydroxylamines give no diastereoselectivity. The concerted additio... N-Alkylhydroxylamines have been shown to undergo a stereospecific cis addition to 1-phenyl-2 -nitropropene compounds, whereas the corresponding O-alkylhydroxylamines give no diastereoselectivity. The concerted addition mechanism was provided to explain the difference. 展开更多
关键词 N-Alkylhydroxylamines O-alkylhydroxylamines concerted addition mechanism α β-unsaturated nitro compounds stereoselectivity.
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Doebner condensation in ionic liquids [Bmim]BF_4 and [Bpy]BF_4 to synthesize α,β-unsaturated carboxylic acid
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作者 Dong Jiang Yuan Yuan Wang Yan Nan Xu Li Yi Dai 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第3期279-282,共4页
Ionic liquids [Bmim]BF4 and [Bpy]BF4 were employed as environmentally benign media in Doebner condensation to synthesize α, β-unsaturated carboxylic acid. The good results showed that [Bmim]BF4 and [Bpy]BF4 were ef... Ionic liquids [Bmim]BF4 and [Bpy]BF4 were employed as environmentally benign media in Doebner condensation to synthesize α, β-unsaturated carboxylic acid. The good results showed that [Bmim]BF4 and [Bpy]BF4 were efficient media for Doebner condensation, which could be recycled easily. The highest yields could reach 93% and 90% in [Bmim]BF4 and [Bpy]BF4, respectively. 展开更多
关键词 Ionic liquid Doebner condensation α β-unsaturated carboxylic acid DECARBOXYLATION
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Conjugate Addition Reactions of Functionalized Organozinc-copper Reagents to α,β-Unsaturated Esters
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作者 Yu Lai HU Jian Hua YU +3 位作者 Shi Yan YANG Yuan Qi YIN Tian Quan JIAO Jin Xian WANG(State. Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of sciences, Lanzhou 730000)(Department of Chemistry, 《Chinese Chemical Letters》 SCIE CAS CSCD 1998年第8期699-700,共2页
Functionalized organozinc reagents can easily conduct 1,4-addition reaction with unsaturated esters in the presence of Cu(OAc)2 and LiCl under very Anld conditions to give the products in excellent yields.
关键词 conjugate addition reaction organozinc reagents α β-unsaturated esters
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Organocatalyzed Highly Efficient Michael Addition of Malonate Derivatives to α,β-Unsaturated Ketones Using Chiral Schiff Bases
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作者 Yonghai Hui Jianzhong Zhang +1 位作者 Wanfu Sun Zhengfeng Xie 《Journal of Chemistry and Chemical Engineering》 2011年第9期847-853,共7页
An efficient enantioselective Michael addition of ethyl-2-cyanoacetate and diethyl malonate to α,β-unsaturated ketones catalyzed by a simple chiral Schiff base, and products were obtained in good yields at room temp... An efficient enantioselective Michael addition of ethyl-2-cyanoacetate and diethyl malonate to α,β-unsaturated ketones catalyzed by a simple chiral Schiff base, and products were obtained in good yields at room temperature. 展开更多
关键词 α β-unsaturated ketones cyanoacetate MALONATE Michael addition Schiffbase.
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Ceric Ammonium Nitrate-mediated Oxidative Cycloaddition of 1,3-Dicarbonyls to β-Aryl-α, β-unsaturated Ketones
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作者 WeiZHANG CongDeHUO ZhengGangLIU ZhongLiLIU 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第4期389-391,共3页
Regio and stereoselective synthesis of substituted dihydrofurans were accomplished by eeric ammonium nitrate mediated oxidative cycloaddition of 1,3-dicarbonyls to β-aryl-α,β-unsaturated ketones in moderate yields.
关键词 cerie ammonium nitrate CYCLOADDITION DIHYDROFURANS dicarbonyls compounds β-ary1 α β-unsaturated ketones
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A New Method for the Transformation of Alkenes intoα, β-Unsaturated Ketones via Cycloaddition with Dichloroketene
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作者 徐福培 ThsanErden JamesR.Keeffe 《Advances in Manufacturing》 SCIE CAS 1997年第3期257-259,共3页
A new synthetic method is described here to obtain α, β-unsaturated ketones through alkenes through a sequence involving f (1) cycloaddition of alkenes with dichloroketene, (2) dechlorination of adducts, (3)acidprom... A new synthetic method is described here to obtain α, β-unsaturated ketones through alkenes through a sequence involving f (1) cycloaddition of alkenes with dichloroketene, (2) dechlorination of adducts, (3)acidpromoted ring-opening isomerization ofcyclobutanones in CF3 CO2H. 展开更多
关键词 alkenes. α β-unsaturated ketones cycloaddition dichloroketene
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Michael Additions of Activated Methylene Compounds to α,β-Unsaturated Esters Promoted by Samarium (Ⅲ) Iodide
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作者 Xiao Yuan CHEN Wei Liang BAO Yong Min ZHANG (Department of Chemistry, Zhejiang University at Xixi Campus, Hangzhou 310028)Department of Chemistry Hunan Jishou University, Hunan Jishou 416000) 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第6期483-484,共2页
Promoted by SmI3 β -diketones, β-ketoesters and α -cyano esters were added to α,β -unsaturated esters to form δ-carbonyl esters in mild conditions in moderate to good yields.
关键词 SAMARIUM Michael addition α β-unsaturated ester β-diketones δ-carbonyl esters
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Ytterbium triflate hydrate catalyzed Michael addition and cyclocondensation of α,β-unsaturated ketones with active methylene compounds
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作者 Zhi Wei Chen Yan Li Wang +1 位作者 Ren Er Chen Wei Ke Su 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第9期1024-1026,共3页
Catalyzed by ytterbium(III) triflate hydrate [Yb(OTf)3.xH20], the Michael addition and cyclocondensation of α,β-unsaturated ketones with active methylene compounds to afford the 1,4-adducts and benzo[b]pyran der... Catalyzed by ytterbium(III) triflate hydrate [Yb(OTf)3.xH20], the Michael addition and cyclocondensation of α,β-unsaturated ketones with active methylene compounds to afford the 1,4-adducts and benzo[b]pyran derivatives, respectively were studied. 展开更多
关键词 Ytterbium(Ⅲ) triflate hydrate α β-unsaturated ketones Active methylene compounds Benzo[b]pyran derivatives
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