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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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Ketone bodies and inflammation modulation:A mini-review on ketogenic diet’s potential mechanisms in mood disorders
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作者 YAN ZHENG SIHUI MA +2 位作者 KATSUHIKO SUZUKI HISANORI KATO HUIJUAN JIA 《BIOCELL》 SCIE 2023年第8期1897-1906,共10页
Mental disorders such as depression and anxiety inflict significant burdens on individuals and society.Commonly prescribed treatments often involve cognitive therapy and medications.However,for patients resistant to t... Mental disorders such as depression and anxiety inflict significant burdens on individuals and society.Commonly prescribed treatments often involve cognitive therapy and medications.However,for patients resistant to these conventional methods,alternative therapies like the Ketogenic Diet(KD)offer a promising avenue.KD and its key metabolite,β-hydroxybutyrate(BHB),have been hypothesized to alleviate mental disorders through antiinflammatory actions,a crucial pathway in the pathophysiology of depression.This mini-review examines 15 clinical trials exploring the influence of KD and BHB on inflammation and their potential roles in managing mental disorders.Both human and animal studies were scrutinized to elucidate possible cellular and molecular mechanisms.Out of the 15 trials,10 reported reduced levels of at least one inflammatory mediator or mRNA post KD or BHB treatment,while two observed an elevation in anti-inflammatory agents.These findings suggest that KD and BHB could modulate cellular inflammatory pathways,highlighting their potential for therapeutic application in mental disorders. 展开更多
关键词 ketone body Ketogenic diet DEPRESSION ANXIETY NEUROINFLAMMATION
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SYNTHESIS AND PROPERTIES OF NOVEL POLY(IMINO KETONE)S AS HIGH-PERFORMANCE POLYMERS 被引量:11
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作者 Chang, Guan-jun Luo, Xuan +1 位作者 Zhang, Lin Lin, Run-xiong 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2008年第1期55-61,共7页
Di(4-bromophenyl)ketone and various aromatic diamines as the monomers,a series of novel poly(imino ketone)s (PIKs)have been synthesized via palladium-catalyzed aryl amination,which is Hartwig-Buchwald polycondensation... Di(4-bromophenyl)ketone and various aromatic diamines as the monomers,a series of novel poly(imino ketone)s (PIKs)have been synthesized via palladium-catalyzed aryl amination,which is Hartwig-Buchwald polycondensation reaction.The structures of PIKs are characterized by means of elemental analysis,FT-IR,~1H-NMR and UV-Vis spectroscopy. The results show a good agreement with the proposed structure.The general properties of PIKs are studied by DSC,TG and wide-angle X-ray diffraction,the solubility behavior is... 展开更多
关键词 Di(4-bromophenyl)ketone Aromatic diamines Palladium-catalyzed aryl amination High-performance Poly(imino ketone
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Preparation of α-Bromoketones and Thiazoles from Ketones with NBS and Thioamides in Ionic Liquids
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作者 Yuhta Izumisawa Hideo Togo 《Green and Sustainable Chemistry》 2011年第3期54-62,共9页
Ketones smoothly reacted with NBS in the presence of a catalytic amount of ptoluenesulfonic acid to give α-bromoketones in good yields in typical ionic liquids, such as [bmim]PF6 and [bmpy]Tf2N, and the ionic liquids... Ketones smoothly reacted with NBS in the presence of a catalytic amount of ptoluenesulfonic acid to give α-bromoketones in good yields in typical ionic liquids, such as [bmim]PF6 and [bmpy]Tf2N, and the ionic liquids could be repeatedly used for the same reaction after the extraction of the α-bromoketones. Then, the one-pot conversion of ketones into thiazoles by the treatment with NBS, and subsequently with thioamides could be also carried out in [bmim]PF6 and [bmpy]Tf2N, respectively Thus, [bmim]PF6 and [bmpy]Tf2N could be used as recyclable reaction media for the preparation α-bromoketones and thiazoles from ketones. 展开更多
关键词 ketone α-Bromoketone Thiazole NBS THIOAMIDE Ionic Liquid
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Synthesis and characterization of quaternized poly(phthalazinone ether sulfone ketone)for anion-exchange membrane 被引量:9
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作者 Xi Gao Jian Chun Yan +3 位作者 Hua Min Zhang Shou Hai Zhang Cheng Liu Ping Zhao 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第10期1269-1272,共4页
Chloromethylated poly(phthalazinone ether sulfone ketone) (CMPPESK) was prepared from poly(phthalazinone ether sulfone ketone) (PPESK) using chloromethyl octyl ethers (CMOE) with lower toxicity as chlorometh... Chloromethylated poly(phthalazinone ether sulfone ketone) (CMPPESK) was prepared from poly(phthalazinone ether sulfone ketone) (PPESK) using chloromethyl octyl ethers (CMOE) with lower toxicity as chloromethylated regent. CMPPESK was soluble in N-methyl-2-pyrrolidone (NMP), N,N-dimethylacetamide (DMAc) and chloroform. Quaternized poly(phthalazinone ether sulfone ketone) (QAPPESK) was prepared from CMPPESK by quaternization. QAPPESK had excellent solvent resistance, which was only partly soluble in sulfuric acid (98%) and swollen in N,N-dimethylformamide (DMF). The vanadium redox flow battery (V-RFB) using QAPPESK anion-exchange membrane had better performance with 88.3% of overall energy efficiency. 展开更多
关键词 CHLOROMETHYLATION QUATERNIZATION Poly(phthalazinone ether sulfone ketone Anion-exchange membrane Vanadium redox flowbattery
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UV-induced Self-initiated Graft Polymerization of Acrylamide onto Poly(ether ether ketone) 被引量:6
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作者 CHEN Rui-chao, SUN Hui, LI Ang and XU Guo-zhi College of Materials Science and Mechanical Engineering, National Center for Quality Supervision and Test of Plastic Products, Beijing Technology and Business University, Beijing 100048, P. R. China 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第1期162-165,共4页
Photo-grafting of hydrophilic monomer was used to enhance the hydrophilicity of poly(ether ether ketone) (PEEK) with the aim of extending its applications to biological fields. PEEK sheets were surface modified by... Photo-grafting of hydrophilic monomer was used to enhance the hydrophilicity of poly(ether ether ketone) (PEEK) with the aim of extending its applications to biological fields. PEEK sheets were surface modified by grafting of acrylamide(AAm) with ultraviolet(UV) irradiation in the presence or absence of benzophenone(BP). The effects of BP, irradiation time and monomer concentration on the surface wettability of PEEK were investigated. Characteriza tion of modified PEEK using scanning electron microscopy(SEM), energy-disperse spectrometer(EDS) and water contact angle measurements shows that AAm was successfully grafted on PEEK surface both in presence and absence of BP. With the increase in irradiation time and monomer concentration, contact angles decrease to as low as 30°, demonstrating a significant improvement of surface hydrophilicity. In agreement with the decrease in contact angle, under identical conditions, the nitrogen concentration increases, suggesting the increase in grafting degree of the grafting polymerization. This investigation demonstrates a self-initiation of PEEK due to its BP-like structure in the backbone of the polymer. Though the graft polymerization proceeds more readily in the presence of BP, the self-initiated graft polymerization is clearly observed. 展开更多
关键词 Poly(ether ether ketone)(PEEK) UV-grafting Surface modification Self-initiation Graft polymerization
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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
关键词 Cerium trichloride heptahydrate Mannich reaction β-Amino ketones Lewis acid
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Synthesis and Crystal Structure of Lanthanum Nitrate with Methyl-2-pyridyl Ketone Benzoyl Hydrazone 被引量:5
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作者 TAIXi-shi YINXian-hong +2 位作者 LIUDe-bo TANMin-yu YUKai-bei 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第4期434-436,共3页
A novel La complex with methyl-2-pyridyl ketone benzoyl hydrazone has been synthesized and determined by single crystal X-ray diffraction. The crystal is monoclinic with space group C2/c, a =1 7081(3) nm, b =1 ... A novel La complex with methyl-2-pyridyl ketone benzoyl hydrazone has been synthesized and determined by single crystal X-ray diffraction. The crystal is monoclinic with space group C2/c, a =1 7081(3) nm, b =1 5660(3) nm, c =1 3512(3) nm, α=90 00°, β=94 39(1)°, γ=90 00°, V =3 6037(12) nm 3, Z =4 . The complex is a ten-coordinated one with a lanthanum ion surrounded by a N 4O 6 set. The crystal structure is stabilized by hydrogen bonds between water molecules and NO - 3 anions. 展开更多
关键词 SYNTHESIS Lanthanum complex Methyl-2-pyridyl ketone benzoyl hydrazone Crystal structure
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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
关键词 Ionic liquids sodium borohydride REDUCTION ALDEHYDE ketone.
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Synthesis and characterization of novel poly(aryl ether sulfone ketone)s containing phthalazinone and biphenyl moieties 被引量:3
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作者 Li Hong Xiao Cheng Liu Xi Gao Jian 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第2期227-229,共3页
A novel series of poly(aryl ether sulfone ketone)s (PPESKs) containing phthalazinone and biphenyl moieties were prepared by two-step nucleophilic polycondensation reaction. The ^-Mw values of these copolymers were... A novel series of poly(aryl ether sulfone ketone)s (PPESKs) containing phthalazinone and biphenyl moieties were prepared by two-step nucleophilic polycondensation reaction. The ^-Mw values of these copolymers were between 38,330 and 67,900. The glass transition temperatures (Tg) and 5% decomposition temperatures were ranged in 253-269 ℃ and 488-500 ℃, respectively, The structures of these copolymers were confirmed by FT-IR and ^1H NMR. Moreover, all the resultant copolymers were amorphous determined by wide angle X-ray diffraction (WAXD). 展开更多
关键词 Poly(aryl ether sulfone ketone PHTHALAZINONE BIPHENYL Thermal property Solubility
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Effects of ketogenic diet and ketone bodies on the cardiovascular system:Concentration matters 被引量:4
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作者 Souad Nasser Varvara Vialichka +2 位作者 Marta Biesiekierska Aneta Balcerczyk Luciano Pirola 《World Journal of Diabetes》 SCIE 2020年第12期584-595,共12页
Ketone bodies have emerged as central mediators of metabolic health,and multiple beneficial effects of a ketogenic diet,impacting metabolism,neuronal pathologies and,to a certain extent,tumorigenesis,have been reporte... Ketone bodies have emerged as central mediators of metabolic health,and multiple beneficial effects of a ketogenic diet,impacting metabolism,neuronal pathologies and,to a certain extent,tumorigenesis,have been reported both in animal models and clinical research.Ketone bodies,endogenously produced by the liver,act pleiotropically as metabolic intermediates,signaling molecules,and epigenetic modifiers.The endothelium and the vascular system are central regulators of the organism’s metabolic state and become dysfunctional in cardiovascular disease,atherosclerosis,and diabetic micro-and macrovascular complications.As physiological circulating ketone bodies can attain millimolar concentrations,the endothelium is the first-line cell lineage exposed to them.While in diabetic ketoacidosis high ketone body concentrations are detrimental to the vasculature,recent research revealed that ketone bodies in the low millimolar range may exert beneficial effects on endothelial cell(EC)functioning by modulating the EC inflammatory status,senescence,and metabolism.Here,we review the long-held evidence of detrimental cardiovascular effects of ketoacidosis as well as the more recent evidence for a positive impact of ketone bodies—at lower concentrations—on the ECs metabolism and vascular physiology and the subjacent cellular and molecular mechanisms.We also explore arising controversies in the field and discuss the importance of ketone body concentrations in relation to their effects.At low concentration,endogenously produced ketone bodies upon uptake of a ketogenic diet or supplemented ketone bodies(or their precursors)may prove beneficial to ameliorate endothelial function and,consequently,pathologies in which endothelial damage occurs. 展开更多
关键词 Endothelial cells ketone bodies Vascular physiology β-Hydroxybutyrate β-Hydroxybutyrylation Histone post-translational modifications
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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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Baeyer-Villiger oxidation of cyclic ketones utilizing potassium peroxydisulfate(K_2S_2O_8) or sodium perborate(NaBO_3) in acidic media 被引量:6
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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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Synthesis and Thermal Crosslinking Behavior of Poly(aryl ether ketone)s Containing 1,4-Naphthalene Moieties 被引量:3
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作者 NIUYa-ming ZHANGYun-he CHENXing-bo WANGGui-bin JIANGZhen-hua 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第1期109-113,共5页
A new monomer, 1,4-bis(4-fluorobenzoyl) naphthalene(compound 2) was synthesized via a two-step reaction. 1,4-Naphthalenedicarboxylic acid chloride(compound 1) was prepared by using the acyl chlorization reaction of 1,... A new monomer, 1,4-bis(4-fluorobenzoyl) naphthalene(compound 2) was synthesized via a two-step reaction. 1,4-Naphthalenedicarboxylic acid chloride(compound 1) was prepared by using the acyl chlorization reaction of 1,4-naphthalenedicarboxylic acid with thionyl chloride. The Friedel-Crafts acylation of compound 1 with fluorobenzene afforded compound 2 in a 80% yield. The polycondensation of compound 2 with various bisphenols in tetramethylene sulfone(TMS) in the presence of excess potassium carbonate as a condensation reagent was carried out at 210 ℃ to quantitatively afford the corresponding poly(aryl ether ketone)s(compounds 3_8) containing 1,4-naphthalene moieties. Thermal analyses showed that the polymers have T g values ranging from 496 to 500 K and are thermally stable in air with initial mass loss above 500 ℃. These novel polymers exhibited an excellent solubility in organic solvents including NMP, DMAc, and chloroform, etc. In addition, the glass transition temperatures of these polymers increased and the polymers became insoluble in chloroform after treated at 260 ℃, indicating the occurrence of a thermal crosslinking reaction. 展开更多
关键词 Poly(aryl ether ketone) Naphthalene derivatives Friedel-Crafts acylation Thermal crosslinking properties
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Synthesis of Poly(phthalazinone ether ketone) Containing Sodium Sulfonate Groups via Direct Polymerization 被引量:3
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作者 Shou Hai ZHANG Xi Gao JIAN +1 位作者 Guo Qing WANG Wen Xia LI 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第10期926-928,共3页
Dihydro-4-(4-hydroxyphenyl)(2H)phthalazin-1-one(DHPZ) was sulfonated in con- centrated sulfuric acid. Poly(phthalazinone ether ketone) containing pendant sodium sulfonate group was synthesized from sulfonated and pure... Dihydro-4-(4-hydroxyphenyl)(2H)phthalazin-1-one(DHPZ) was sulfonated in con- centrated sulfuric acid. Poly(phthalazinone ether ketone) containing pendant sodium sulfonate group was synthesized from sulfonated and pure 1,2-dihydro-4-(4-hydroxyphenyl)(2H)phthalazin- 1-one, and 4,4-difluorodiphenylketone. The sulfonated monomer and sulfonated polymer were characterized with FT-IR and 1H-NMR. 展开更多
关键词 SULFONATION SYNTHESIS poly(phthalazinone ether ketone)
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Immobilization of Bovine Serum Albumin on Poly(ether ether ketone) for Surface Biocompatibility Improvement 被引量:4
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作者 SUN Hui CHEN Rui-chao +1 位作者 LI Ang XU Guo-zhi 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第2期353-357,共5页
UV-induced graft polymerization of acrylic acid(AA) on poly(ether ether ketone)(PEEK) films was carried out to introduce ―COOH for the subsequent immobilization of bovine serum albumin(BSA).BSA was introduced... UV-induced graft polymerization of acrylic acid(AA) on poly(ether ether ketone)(PEEK) films was carried out to introduce ―COOH for the subsequent immobilization of bovine serum albumin(BSA).BSA was introduced on PEEK surface based on the condensation reaction between ―NH 2 and ―COOH.The modified surface(PEEK-BSA) was characterized by energy-disperse spectrometry(EDS),X-ray photoelectron spectroscopy(XPS),water contact angle measurement and UV spectrum analysis.The contact angle was found to decrease from 104° for the virgin PEEK films to 63° for the BSA-immobilized PEEK films,demonstrating a significant improvement of surface hydrophilicity.Moreover,the appearance of nitrogen on PEEK film confirmed by XPS and EDS indicates the immobilization of BSA on PEEK surface. 展开更多
关键词 Poly(ether ether ketone)(PEEK) UV-grafting Bovine serum albumin immobilization
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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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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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