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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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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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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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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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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 cycloaddition of N-acyliminium cations withα,β-unsaturated ketones and esters
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作者 Ling Feng Qian Yue Hua Zhou Wei Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第7期805-808,共4页
The cycloaddition of N-acyliminium cations with some deactivated alkenes such as α,β-unsaturate ketones and esters has been investigated. In most cases, the N-acyliminium cations produced from 3-hydroxy-2-arylisoind... The cycloaddition of N-acyliminium cations with some deactivated alkenes such as α,β-unsaturate ketones and esters has been investigated. In most cases, the N-acyliminium cations produced from 3-hydroxy-2-arylisoindol-1-ones in the presence of BFa.OEt2 could be reacted with α,β-unsaturated ketones and esters to afford stereoselectively the cycloaddition products 6-acylisoindolo[2,1- a]quinolin-11-ones in moderate to high yields. C 2009 Wei Zhang. Published by Elsevier B.V, on behalf of Chinese Chemical Society. All rights reserved. 展开更多
关键词 CYCLOADDITION N-acyliminium cation 3-Hydroxy-2-arylisoindol- 1-one α β-unsaturated ketones 6-Acylisoindolo[2 1-a]quinolin- 11- ones
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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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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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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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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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Enantioselective[3 t 2]cycloadditions of terminal allenoates withβ-sulfonyl-α,β-unsaturated ketones
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作者 Xiuzheng Li Jun Liao +4 位作者 Xiaobin Zhuo Huamin Wang Xiaoyun Chai Yan Zou Qingjie Zhao 《Green Synthesis and Catalysis》 2023年第1期54-57,共4页
A highly efficient and mild method for[3 t 2]cycloaddition ofβ-sulfonyl-α,β-unsaturated ketones with terminal allenoates was well-explored and developed.The reactions were successfully performed by applying multifu... A highly efficient and mild method for[3 t 2]cycloaddition ofβ-sulfonyl-α,β-unsaturated ketones with terminal allenoates was well-explored and developed.The reactions were successfully performed by applying multifunctional chiral phosphine P6 which was screened from eight chiral phosphorus reagents to finally result in a variety of enantioenriched sulfone-substituted cyclopentenes with two chiral centers(up to 81%yield with 94%ee).Moreover,2.5 mol%catalytic equivalents were proved to be feasible when this reaction was performed on a 10 mmol scale. 展开更多
关键词 [3t2]Cycloadditions Terminal allenoates α β-unsaturated ketones ENANTIOSELECTIVE Chiral phosphine
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Visible-Light-Induced[4+1]Cyclization-Aromatization of Acylsilanes andα,β-Unsaturated Ketones 被引量:1
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作者 Zhihong Zhu Weilu Zhang +2 位作者 Yizhi Zhang Shanshan Liu Xiao Shen 《CCS Chemistry》 CAS CSCD 2023年第2期325-333,共9页
Herein we report the first[4+1]cyclization-aromatization reaction of acylsilanes andα,β-unsaturated ketones.The unprecedented visible-light-induced reaction proceeded through mild conditions without addition of any ... Herein we report the first[4+1]cyclization-aromatization reaction of acylsilanes andα,β-unsaturated ketones.The unprecedented visible-light-induced reaction proceeded through mild conditions without addition of any catalyst or additive,affording a variety of furans with broad substrate scope and good functional-group tolerance.The synthetic utility of the method was demonstrated by various downstream transformations of the otherwise difficult-to-access sulfone-containing silyl furans.The mechanism study reveals that 1,4-diketones are not likely to be the intermediates of the reaction. 展开更多
关键词 acylsilane α β-unsaturated ketone CARBENE photo chemistry cyclization-aromatization FURAN
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Asymmetric Hydrogenation of Tetrasubstituted α,β-Unsaturated Ketones:Access to Chiral 2-Substituted Cyclopentyl Aryl Ketones
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作者 Zhengdong Ding Feng Gao +3 位作者 Yining Lu Qianjia Yuan Wei-Ping Deng Wanbin Zhang 《Precision Chemistry》 2023年第3期146-152,共7页
Asymmetric hydrogenation of tetrasubstituted alkenes is an important but challenging research topic.Herein,we report an efficient iridium-catalyzed asymmetric hydrogenation of tetrasubstituted α,β-unsaturated ketone... Asymmetric hydrogenation of tetrasubstituted alkenes is an important but challenging research topic.Herein,we report an efficient iridium-catalyzed asymmetric hydrogenation of tetrasubstituted α,β-unsaturated ketones for the synthesis of chiral 2-substituted cyclopentyl aryl ketones,an important chiral structural motif for the preparation of chiral pharmaceuticals and bioactive molecules.The reaction proceeded very well with good functional group compatibility and delivered the hydrogenated products in high yields and stereoselectivities(up to 99% yield,>20:1 dr and 99%ee).In addition,the reaction could be carried out on a gram-scale,and all four stereoisomers of the hydrogenated products bearing two contiguous stereocenters were obtained.Furthermore,the hydrogenated product can be transformed into the ERβ agonist Erteberel,and the reaction pathway was also studied via deuterium-labelling experiments. 展开更多
关键词 asymmetric hydrogenation tetrasubstituted alkenes IRIDIUM chiral cyclopentane 2-substituted cyclopentyl aryl ketones
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Conjugate Addition of Indoles to α, β-Unsaturated Ketones (Chalcones) Catalyzed by KHSO4 under Ultrasonic Conditions 被引量:2
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作者 曾晓飞 纪顺俊 沈舒苏 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2007年第12期1777-1780,共4页
Conjugate addition of indoles to a variety of α,β-unsaturated ketones (chalcones) mediated by a catalytic amount of KHSO4 at room temperature under ultrasonic conditions to afford the corresponding Michael adducts... Conjugate addition of indoles to a variety of α,β-unsaturated ketones (chalcones) mediated by a catalytic amount of KHSO4 at room temperature under ultrasonic conditions to afford the corresponding Michael adducts in good to excellent yields was reported. 展开更多
关键词 KHSO4 INDOLES α β-unsaturated ketones conjugate addition reaction
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Efficient synthesis of terminal α,β-unsaturated ketones as the intermediates of the proteasome epoxyketone inhibitors via Weinreb amide
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作者 吕杨 邹晓民 +4 位作者 牟科 傅翌秋 马超 周博 徐萍 《Journal of Chinese Pharmaceutical Sciences》 CAS 2009年第1期33-36,共4页
Peptidyl epoxyketones were potential antitumor agents due to their 20S proteasome inhibitory activities. Based on their structures and special inhibitory mechanism, a series of compounds were designed by linking the e... Peptidyl epoxyketones were potential antitumor agents due to their 20S proteasome inhibitory activities. Based on their structures and special inhibitory mechanism, a series of compounds were designed by linking the epoxyketone moiety (the Cterminal pharmacophore) and the peptide backbones. To make these compounds, we used a novel method to prepare the terminal α,β-unsaturated ketone, the crucial intermediate, from Weinreb amide with satisfactory yield (62%-65%). 展开更多
关键词 Epoxyketone SYNTHESIS α β-unsaturated ketone Weinreb amide
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Catalytic conjugate addition of indole toα,β-unsaturated ketones by Co(ClO_4)-2·6H_2O/bis-Schiff base complexes 被引量:1
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作者 Yong Hai Hui Chun Mei Chen Zheng Feng Xie 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第5期525-528,共4页
Co(ClO_4))_2·6H_2O/bis-Schiff base complexes promoted the conjugate addition of indole toα,β-unsaturated ketones under mild conditions,giving the corresponding addition products with high yields.And the comp... Co(ClO_4))_2·6H_2O/bis-Schiff base complexes promoted the conjugate addition of indole toα,β-unsaturated ketones under mild conditions,giving the corresponding addition products with high yields.And the complex has been characterized with XRD and IR. 展开更多
关键词 Conjugate addition INDOLE α β-unsaturated ketone Schiff base
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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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Enantioselective Hydrogenation of α,β-Unsaturated Cyclic Ketones by Double Asymmetric Induction Preparation of (R)-Muscone 被引量:1
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作者 Bao Han XIE Shi Jie LU +1 位作者 Hong Xiang FU Lan Yong GAO (State Key Laboratory for Oxo Srnthesis and Selective Oxidation Lanzhou Institute of Chemical Physics. Chinese Academy of Sciences, Lanzhou 730000) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第6期477-478,共2页
By ketal formation with chiral glycols like methyl or ethyl ester of tartaric acid,hydrogenation of ketals from the correspondingα,β-unsaturated 15-membered cyclic ketone produces (R)-muscone in good chemical and op... By ketal formation with chiral glycols like methyl or ethyl ester of tartaric acid,hydrogenation of ketals from the correspondingα,β-unsaturated 15-membered cyclic ketone produces (R)-muscone in good chemical and optical yield in the presence of chiral catalysts 展开更多
关键词 Unsaturated Cyclic ketones by Double Asymmetric Induction Preparation of MUSCONE
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Asymmetric epoxidation of α,β-unsaturated ketones using α,α-diarylprolinols as catalysts 被引量:1
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作者 ZHENG ChangWu ZHAO Gang 《Chinese Science Bulletin》 SCIE EI CAS 2010年第17期1712-1722,共11页
Asymmetric epoxidation of α,β-unsaturated ketones has been extensively studied and several important procedures have been developed in the last decade. This review addresses the most significant advances in asymmetr... Asymmetric epoxidation of α,β-unsaturated ketones has been extensively studied and several important procedures have been developed in the last decade. This review addresses the most significant advances in asymmetric epoxidation of α,β-unsaturated ketones using proline-derived α,α-diarylprolinols as catalysts. Special attention has been paid to the enantioselective epoxidation of chalcones, α,β-unsaturated trifluoromethyl, trichloromethyl ketones and β,γ-unsaturated α-keto esters based on the reseach of our group. 展开更多
关键词 β-不饱和酮 不对称环氧化 催化剂 对映选择性 三氟甲基 脯氨酸 查尔酮 甲基酮
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Transition Metal Free Chemoselective Reduction ofα,β-Unsaturated Ketones to Saturated Ketones Using Tosyl Hydrazide as a Hydrogen Donor
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作者 Yarabally R Girish Kanchipura R Raghavendra +2 位作者 Dasappa Nagaraja Kothanahally S Sharath Kumar Sheena Shashikanth 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2015年第2期181-184,共4页
An efficient,inexpensive and simple method for the reduction of variousα,β-unsaturated ketones to corre-sponding saturated ketones using tosyl hydrazide as a hydrogen donor in DMF using calcium oxide powder has been... An efficient,inexpensive and simple method for the reduction of variousα,β-unsaturated ketones to corre-sponding saturated ketones using tosyl hydrazide as a hydrogen donor in DMF using calcium oxide powder has been reported.A variety of enones underwent reduction without forming undesirable side products.High chemose-lectivity,broad functional group tolerance and good yields are the noteworthy features of this protocol. 展开更多
关键词 α β-unsaturated carbonyl compounds tosyl hydrazide transition metal free saturated ketones
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