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One-pot Synthesis of MoO_(3)/PI Composite with Enhanced Photocatalytic Performance for Oxidative Coupling of Amines to Imines
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作者 Zhao Wenjie Du Chengxin +4 位作者 Song Yu Zhou Yafen Wang Qing Zhou Limei Xu Bin 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第2期57-71,共15页
Organic-inorganic MoO_(3)/PI(MoPI)composites were prepared using a simple one-pot thermal copolymerization method.The resulting composites exhibited enhanced photocatalytic activity for the selective oxidation of benz... Organic-inorganic MoO_(3)/PI(MoPI)composites were prepared using a simple one-pot thermal copolymerization method.The resulting composites exhibited enhanced photocatalytic activity for the selective oxidation of benzylamine to N-benzylidene benzylamine(N-BDBA)in ambient air under simulated solar light irradiation compared to pristine MoO_(3) or polyimide(PI).In particular,the MoPI composite with a 0.3:1 molar ratio of Mo to melamine,referred to as MoPI-0.3,demonstrated the best performance in the photo-oxidation of benzylamine,achieving a benzylamine conversion of 95%with a N-BDBA selectivity exceeding 99%after 3 h irradiation.The enhanced photocatalytic activity of the MoPI-0.3 catalyst was attributed to the formation of a direct Z-scheme heterojunction between MoO_(3) and PI,facilitating more efficient separation of the photoinduced electrons and holes.Additionally,the MoPI-0.3 composite maintained considerably high activity over four consecutive cycles,highlighting its good stability and recyclability.Furthermore,the MoPI-0.3 composite could photo-oxidize benzylamine derivatives and heterocyclic amines to their corresponding imines,demonstrating the universal applicability of this composite catalyst. 展开更多
关键词 MoO3/PI composite photocatalysis amine oxidation IMINE
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A Metal-free Polyimide Photocatalyst for the Oxidation of Amines to Imines 被引量:1
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作者 Zhou Yafen Cheng Hong +5 位作者 Song Yu Wang Qing Zhao Wenjie Chen Qilin Zhou Limei Xu Bin 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2023年第3期92-103,共12页
Polyimide(PI) is an organic polymer material with good stability and diverse sources that has attracted widespread attention in the field of photocatalysis. In this study, a series of PI photocatalysts were synthesize... Polyimide(PI) is an organic polymer material with good stability and diverse sources that has attracted widespread attention in the field of photocatalysis. In this study, a series of PI photocatalysts were synthesized by a thermal polymerization approach using pyromellitic dianhydride(PMDA) and various diamine monomers(melamine(MA), 4,4′-oxydianiline, and melem) as the precursors as well as different heating rates. The effects of the diamine precursor and heating rate on the structure, composition, morphology, and optical properties of the as-prepared PI materials were systematically investigated by various characterization techniques. The selective photo-oxidation of benzylamine was used as a model reaction to evaluate the photocatalytic activities of the resulting PI samples for the oxidation of amines to imines. The results revealed that the PI sample prepared using MA and PMDA as the precursors and a heating rate of 7 ℃/min(MA-PI-7) exhibited the best catalytic performance, with 98% benzylamine conversion and 98% selectivity for N-benzylidene benzylamine after 4 h of irradiation. Several benzylamine derivatives and heterocyclic amines also underwent the photo-oxidation reaction over the MA-PI-7 catalyst to afford the corresponding imines with good activity. In addition, MA-PI-7 exhibited good stability over four successive photocatalytic cycles. 展开更多
关键词 POLYIMIDE PHOTOCATALYST OXIDATION amine IMINE
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Addition of Allyltrimethylsilane to tert-Butanesulfinyl Imines Triggered by Tetra-n-butylammonium Fluoride 被引量:1
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作者 Wan Xuan ZHANG Xue Long HOU 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第8期1037-1040,共4页
The addition of allyltrimethylsilane to tert-butanesulfinyl imines triggered by tetra-n-butylammonium fluoride (TBAF) in the presence of 4A molecular sieves has been studied, and homoallylsulfinamides were obtained ... The addition of allyltrimethylsilane to tert-butanesulfinyl imines triggered by tetra-n-butylammonium fluoride (TBAF) in the presence of 4A molecular sieves has been studied, and homoallylsulfinamides were obtained in good yields with moderate to high diastereoselectivities. 展开更多
关键词 Stereoselective addition tert-butanesulfinyl imines ALLYLTRIMETHYLSILANE tetra-n-butylammonium fluoride.
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Synthesis and extractive properties of bisthiophosphorylimines
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作者 唐瑞仁 石晓明 +1 位作者 张启修 唐子龙 《Journal of Central South University of Technology》 EI 2008年第3期329-333,共5页
Novel transition metal complexes of bis(diarylsubstitutedthiophosphoryl)imines ligand derived from O,O-di(p-methoxylphenyl)thiophosphoryl chloride and O,O-di-(p-methoxylphenyl)thiophosphoryl amine with Cu(Ⅱ ),Co( Ⅱ)... Novel transition metal complexes of bis(diarylsubstitutedthiophosphoryl)imines ligand derived from O,O-di(p-methoxylphenyl)thiophosphoryl chloride and O,O-di-(p-methoxylphenyl)thiophosphoryl amine with Cu(Ⅱ ),Co( Ⅱ) ,Ni( Ⅱ) ,Fe(Ⅱ ) and Mn( Ⅱ ) were synthesized. The formation mechanism of complexes and their stereochemistry structures were investigated according to elemental analysis,infrared spectra and 31P-nuclear magnetic resonance spectra. The extractions of the ligand for different divalent metal ions,such as Zn(Ⅱ ),Cd( Ⅱ) ,Cu( Ⅱ) ,Ni( Ⅱ ),Fe( Ⅱ) ,Sn( Ⅱ) ,Mn( Ⅱ) ,Pd( Ⅱ) ,Hg( Ⅱ) and Fe(Ⅲ),were investigated in sulphate solution,respectively. The results show the metal atom is coordinated by 4 sulfur atoms in a square-planar fashion,and the titled compound has not only powerful ability to coordinate with cadmium from aqueous solution with a high extractive rate about 61.20% and a relatively weak complexation for other divalent metals with the extractive rate from 2.46% to 36.66%,but also a good selectivity to Fe(Ⅲ ). 展开更多
关键词 bis(thiophosphoryl)imines transition metal complexes SYNTHESIS EXTRACTION
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Efficient Solvent-Free Preparation of Imines, and Their Subsequent Oxidation with <i>m</i>-CPBA to Afford Oxaziridines
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作者 Luis álvarez-Santamaría Eusebio Juaristi +3 位作者 Alexa Berenice Arroyo-Colín Jorge Palma-Flores Fanny Araceli Cabrera-Rivera Jaime Escalante 《Green and Sustainable Chemistry》 2019年第4期143-154,共12页
A simple one-pot procedure for the preparation of imines from the corresponding aldehydes and amines, and their subsequent oxidation reaction with m-CPBA to produce synthetically useful oxaziridines is reported. The m... A simple one-pot procedure for the preparation of imines from the corresponding aldehydes and amines, and their subsequent oxidation reaction with m-CPBA to produce synthetically useful oxaziridines is reported. The method is applicable to imines derived from both aliphatic and aromatic aldehydes and diverse alkyl amines. Short reaction times, essentially quantitative yields, very mild reaction conditions, and easy purification are the main features of the procedure reported herein. 展开更多
关键词 SOLVENT-FREE REACTION imines Oxaziridines OXIDATION REACTION M-CPBA
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Aerobic oxidative coupling of alcohols and amines to imines over iron catalysts supported on mesoporous carbon 被引量:1
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作者 Longlong Geng Jinling Song +4 位作者 Bin Zheng Shujie Wu Wenxiang Zhang Mingjun Jia Gang Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第9期1451-1460,共10页
Direct oxidative coupling of an alcohol and amine,with air or molecular oxygen as the oxygen source,is an environmentally friendly method for imine synthesis.We developed an Fe catalyst supported on mesoporous carbon... Direct oxidative coupling of an alcohol and amine,with air or molecular oxygen as the oxygen source,is an environmentally friendly method for imine synthesis.We developed an Fe catalyst supported on mesoporous carbon(denoted by FeOx/HCMK-3) for this reaction with excellent activity and recyclability.FeOx/HCMK-3 was prepared by impregnating HNO3-treated mesoporous carbon(CMK-3) with iron nitrate solution.The highly dispersed FeOx species give FeOx/HCMK-3 high reducibility and are responsible for the high catalytic performance.Imine synthesis over FeOx/HCMK-3 follows a redox mechanism.The oxygen species in FeOx/HCMK-3 participate in the reaction and are then regenerated by oxidation with molecular O2.The reaction involves two consecutive steps:oxidative dehydrogenation of an alcohol to an aldehyde and coupling of the aldehyde with an amine to give an imine.Oxidative dehydrogenation of the alcohol is the rate-determining step in the reaction. 展开更多
关键词 Iron catalyst Imine synthesis Oxidative coupling Mesoporous carbon Molecular oxygen
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Controllable synthesis of novel nanoporous manganese oxide catalysts for the direct synthesis of imines from alcohols and amines
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作者 Fushan Chen Songlin Zhao +5 位作者 Tao Yang Taotao Jiang Jun Ni Houfeng Xiong Qunfeng Zhang Xiaonian Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第10期2438-2446,共9页
A novel template-free oxalate route was applied to synthesize different mesoporous manganese oxides(amorphous manganese oxide(AMO),Mn5 O8,Mn3 O4,Mn O2)in the narrow temperature range from 350°C to 400°C by c... A novel template-free oxalate route was applied to synthesize different mesoporous manganese oxides(amorphous manganese oxide(AMO),Mn5 O8,Mn3 O4,Mn O2)in the narrow temperature range from 350°C to 400°C by controlling the calcination conditions,which were employed as the efficient catalysts for the oxidative coupling of alcohols with amines to imines.The chemical and structural properties of the manganese oxides were characterized by the methods of thermogravimetry analysis and heat flow(TG-DSC),X-ray diffraction(XRD),nitrogen sorption,scanning electron microscope(SEM),transmission electron microscopy(TEM),X-ray photoelectron spectroscopy(XPS),H2 temperature-programmed reduction(H2-TPR),and inductively coupled plasma optical emission spectrometry(ICP-OES)techniques.The structures of different manganese oxides were confirmed by characterization.The M-350(AMO)presented the maximum surface area,amorphous nature,the lowest reduction temperature,the higher(Mn3++Mn4+)/Mn2+ratio,and the higher adsorbed oxygen species compared to other samples.Among the catalysts,M-350 showed the best catalytic performance using air as an oxidant,and the conversion of benzyl alcohol(BA)and the selectivity of N-benzylideneaniline(NBA)reached as high as 100%and 97.1%respectively at the lower reaction temperature(80°C)for 1 h.M-350 had also the highest TOF value(0.0100 mmol·mg-1·h-1)compared to the other manganese oxide catalysts.The catalyst was reusable and gave 95.8%conversion after 5 reuse tests,the XRD pattern of the reactivated M-350 did not show any obvious change.Lattice oxygen mobility and(Mn3++Mn4+)/Mn2+ratio were found to play the important roles in the catalytic activity of aerobic reactions. 展开更多
关键词 OXALATE route CONTROLLABLE SYNTHESIS Manganese oxide IMINE SYNTHESIS Heterogeneous catalysis Aerobic oxidation
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Practical reduction of imines by NaBH_4/alumina under solvent-free conditions:An efficient route to secondary amine
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作者 Foad Kazemi Ali Reza Kiasat Ebrahim Sarvestani 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第10期1167-1170,共4页
Sodium borohydride supported on alumina reduces imines to the corresponding secondary amines in high to excellent isolated yields under solvent-free conditions. Noteworthy is that highly chemoselective reactions were ... Sodium borohydride supported on alumina reduces imines to the corresponding secondary amines in high to excellent isolated yields under solvent-free conditions. Noteworthy is that highly chemoselective reactions were achieved in the presence of other functional groups such as halogen, nitro, and cyano groups. 展开更多
关键词 IMINE Secondary amine Solvent free REDUCTION Sodium borohydride
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Photochemical Reduction of Aromatic Imines by 2-Phenyl-N, N-dimethylbenzimidazoline
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作者 Mei Zhong JIN Li YANG +2 位作者 Long Ming WU You Chen LIU Zhong Li LIU 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第4期307-308,共2页
A series of aromatic imines were reduced to corresponding amines in excellent yields by 2-phenyl-N. N-dimethylbenzimidazoline (PDMBI) photochemically in the presence of magnesium perchloride (Mg(ClO4)(2)). A Mg2+ medi... A series of aromatic imines were reduced to corresponding amines in excellent yields by 2-phenyl-N. N-dimethylbenzimidazoline (PDMBI) photochemically in the presence of magnesium perchloride (Mg(ClO4)(2)). A Mg2+ mediated photoinduced electron transfer mechanism was proposed. 展开更多
关键词 Photoinduced electron transfer selective reduction IMINE PDMBI
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Study on Unexpected Cycloaddition Reactions of Imines with THF
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作者 Jun ZHAO Ping XIE +1 位作者 Shu Feng CHEN Xiao Tian LIANG (Institute of Materia Medica ,Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第6期475-478,共4页
An unexpected tricyclic compound 2,3,3a,4,5,9b-hexahydrophenylfuro[3.2-c] quinoline 4 and its aromatized product 6 were obtained when the cycloaddtion of imine 1 and substituted norbornene 2 was carried out in THF wit... An unexpected tricyclic compound 2,3,3a,4,5,9b-hexahydrophenylfuro[3.2-c] quinoline 4 and its aromatized product 6 were obtained when the cycloaddtion of imine 1 and substituted norbornene 2 was carried out in THF with a catalytic amount of boron trifluoride. The structures of the products were determined by spectral data and the mechanism of reaction was substantiated by the imitation reaction. 展开更多
关键词 IMINE THF cycloaddition reaction
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Environmentally Friendly Syntheses of Imines Applying the Pressure Reduction Technique: Reaction Cases of Less Reactive Amines and Studies by Computational Chemistry
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作者 Shoko Suzuki Hiroyuki Ito +9 位作者 Motoyoshi Noike Shinji Ishizuka Risehiro Nonaka Kenji Funaki Takeshi Kodama Shujiro Sakaki Tomomichi Nishino Mina Ito Toranosuke Takahasi Yasuo Yokoyama 《Green and Sustainable Chemistry》 2020年第1期1-17,共17页
Recently, the development of environmentally friendly syntheses of imine derivatives, which were attracting great attention for their reactivity and structure in various fields, progressed rapidly because the concept ... Recently, the development of environmentally friendly syntheses of imine derivatives, which were attracting great attention for their reactivity and structure in various fields, progressed rapidly because the concept of green chemistry had deeply penetrated into society. In our previous work, we had reported new synthetic methods of imine derivatives using some active amines under solvent- and catalyst-free reaction conditions. This synthetic reaction proceeded smoothly and target compounds were obtained in excellent yields. In this system, when less reactive amines were used as substrates, the synthetic reaction was not finished in the short reaction time, and the corresponding compounds were given in moderate yields. In order to solve this point, we tried to improve the reaction conditions of this method. Through this improvement, it was found that pure target compounds could be obtained in excellent yields by using 1.1 equivalents of less reactive amines to aldehydes and extending the reaction time compared with our previous work. In this paper, we will introduce the detail of this study, and also report the result of the investigation of the reaction property by computational chemistry. 展开更多
关键词 SOLVENT-FREE CATALYST-FREE Pressure REDUCTION TECHNIQUE IMINE Computational Chemistry
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Mannich-Type Reaction of Aldimines with 2-Silyloxydienes Catalyzed by Ammonium Chloride
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作者 Shoichi Fukumoto Miho Shigenobu Kaori Ishimaru 《International Journal of Organic Chemistry》 2019年第4期163-173,共11页
Reaction of imines with 2-silyloxydiene catalyzed by ammonium chloride has been perfectly proceeded under environmentally friendly conditions to give Mannich-type product selectively. The reaction would proceed via Ma... Reaction of imines with 2-silyloxydiene catalyzed by ammonium chloride has been perfectly proceeded under environmentally friendly conditions to give Mannich-type product selectively. The reaction would proceed via Mannich-type mechanism, not cyclization/ring-opening process. Cyclopropanation of the corresponding Mannich-type product gave the precursor of prasugrel skeleton in high yield. 展开更多
关键词 Mannich-Type Reaction AMMONIUM CHLORIDE IMINE 2-Silyloxydiene
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Carbohydrate-Derived Organocatalysts for the Reduction of Imines with Trichlorosilane
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作者 Xin Ge Chao Qian Xinzhi Chen 《Journal of Materials Science and Chemical Engineering》 2015年第6期48-53,共6页
The backbone of D-glucosamine hydrochloride was fine-tuned and modified by protecting the hydroxyl groups. In order to reduce imines with trichlorosilane, the carbohydrate-derived organocatalysts were prepared and scr... The backbone of D-glucosamine hydrochloride was fine-tuned and modified by protecting the hydroxyl groups. In order to reduce imines with trichlorosilane, the carbohydrate-derived organocatalysts were prepared and screened. Methyl-4,6-O-benzylidene-2-amino-2-deoxy-α-D-glucopyr anoside was found as the best catalyst. The reduction was proceeded under CHCl3 as solvent at 40?C, affording 68% - 94% yield. 展开更多
关键词 CARBOHYDRATE ORGANOCATALYST REDUCTION Imine
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Selective photosynthesis of imines from biomass-derived aldehydes over Ni/TiO_(2)
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作者 Wu-Lin Li Qing-Qing Zhang +3 位作者 Lin Dong Wen-Jun Zhang Li-Li Lin Zu-Peng Chen 《Rare Metals》 SCIE EI CAS CSCD 2024年第3期1116-1124,共9页
Photocatalytic reductive amination of biomass-derived aldehydes is a desirable way to selectively upgrade biomass into value-added nitrogen-containing chemicals under mild conditions.However,it is challenging to produ... Photocatalytic reductive amination of biomass-derived aldehydes is a desirable way to selectively upgrade biomass into value-added nitrogen-containing chemicals under mild conditions.However,it is challenging to produce imines in high selectivity because of the undesirable side reactions caused by the activity of functional groups.Here,we demonstrate the highly reactive and selective production of imines from biomass derived aldehydes via the photocatalytic reductive amination,using a defective TiO_(2)supported nickel catalyst.The employment of methanol as the hydrogen donor and ammonia solution as the nitrogen source avoids the use of high-pressure H_(2)and expensive amines,rendering the current catalytic process safe,economical,and environmentally friendly.In depth investigations attribute the improved separation and transfer of photogenerated charge carriers to the presence of oxygen vacancies and decorated Ni nanoparticles,thereby accelerating the production of imines from benzaldehyde amination(conversion,95.8%;seleetivity,95.2%).Furthermore,the developed system could be easily translated to the photocatalytic conversions of various biomass derived aldehydes,which provided an example of a cost-effective and sustainable approach for the valorization of biomass derived feedstocks. 展开更多
关键词 PHOTOCATALYSIS Biomass derivatives imines Reduction amination Heterogeneous catalyst
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Asymmetric Transfer Hydrogenation of Stable NH Imines for the Synthesis of Enantiopure α-Chiral Primary Amines
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作者 Mangang Zhang Hui Li +4 位作者 Keqin Wu Nianxin Rong Shaoquan Lin Hua Yang Qin Yin 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2024年第18期2211-2216,共6页
Although it offers a direct route to access synthetically valuableα-chiral primary amines,asymmetric transfer hydrogenation of NH imines has been rarely studied,due in large part to the inaccessibility and instabilit... Although it offers a direct route to access synthetically valuableα-chiral primary amines,asymmetric transfer hydrogenation of NH imines has been rarely studied,due in large part to the inaccessibility and instability of NH imines.Herein,we report a Rh-catalyzed asymmetric transfer hydrogenation of a kind of novel and stable NH imines which are prepared via condensation of easily available sulfonylated 2'-aminoacetophenones with NH3 in methanol.With this method,enantioenriched chiral 2-(1-aminoalkyl)anilines,which are privileged pharmacore groups,have been synthesized with good functional group compatibility,and with up to 99%ee.A gram-scale reaction using 0.2 mol%of catalyst has been successfully performed to highlight the practicality.Furthermore,the products can be derivatized into enantiopure bioactive molecules as well as chiral tridentate ligands for metal catalysis. 展开更多
关键词 Asymmetric transfer hydrogenation Asymmetric hydrogenation α-Chiral primary amine NH imines 2-(1-Aminoalkyl)anilines
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Iridium-Catalyzed Asymmetric Hydrogenation of Dialkyl Imines
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作者 Zheng Wang Xin-Yi Yang +1 位作者 Yue Xu Qi-Lin Zhou 《CCS Chemistry》 CSCD 2024年第4期905-911,共7页
Asymmetric hydrogenation of dialkyl imines to chiral amines is difficult because the two alkyls of imines are so similar in spatial and electronic structure that chiral catalysts are difficult to distinguish between t... Asymmetric hydrogenation of dialkyl imines to chiral amines is difficult because the two alkyls of imines are so similar in spatial and electronic structure that chiral catalysts are difficult to distinguish between them.In this study,we described an asymmetric hydrogenation of dialkyl imines by a chiral iridium catalyst containing spiro phosphine-amine-phosphine ligand.By precisely adjusting the chiral pocket of catalyst,a highly efficient catalyst was developed.Using this catalyst,a variety of dialkyl imines were hydrogenated to chiral amines with high yield and enantioselectivity. 展开更多
关键词 spiro PNP ligand iridium catalyst enantioselective hydrogenation dialkyl imines chiral amines
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Catalyst-free and atom-economical [4+3] cycloaddition of azadienes with cyclic azomethine imines for facile synthesis of 1,2,4-triazepines
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作者 Lesong Li Tao Liu +1 位作者 Weiwu Ren Yang Wang 《Green Synthesis and Catalysis》 2024年第1期57-61,共5页
A catalyst-free and atom-economical[4+3]cycloaddition of azadienes with C,N-cyclic azomethine imines has been developed,providing an efficient and environmentally benign access to 1,2,4-triazepines with high diastereo... A catalyst-free and atom-economical[4+3]cycloaddition of azadienes with C,N-cyclic azomethine imines has been developed,providing an efficient and environmentally benign access to 1,2,4-triazepines with high diastereoselectivities and yields.This reaction can be performed in 2-methyltetrahydrofuran under mild conditions smoothly. 展开更多
关键词 CATALYST-FREE Atom-economical[4+3] Cycloaddition C N-cyclic Azomethine imine Azadiene 1 2 4-triazepine
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Diastereoselective and Enantioselective Nickel-Catalyzed Reductive Coupling of Imines and Unactivated Alkenes 被引量:1
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作者 Biao Wang Xian-Ming Liu +3 位作者 Kai-Xiang Zhang Wei-Min Feng Li-Jun Xiao Qi-Lin Zhou 《CCS Chemistry》 CSCD 2023年第4期814-822,共9页
Herein we report a method for highly diastereoselective and enantioselective nickel-catalyzed reductive coupling of imines and unactivated alkenes.A monodentate chiral spiro phosphoramidite ligand is the key to contro... Herein we report a method for highly diastereoselective and enantioselective nickel-catalyzed reductive coupling of imines and unactivated alkenes.A monodentate chiral spiro phosphoramidite ligand is the key to controlling the enantioselectivity.This efficient,straightforward method allows for the construction of chiral benzocyclic and indole-fused cyclic amines with two contiguous stereogenic centers in good yields from readily accessible starting materials. 展开更多
关键词 nickel catalysis ENANTIOSELECTIVE ALKENES imines reductive coupling
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Base-controlled annulation of tryptamine-derived isocyanides with nitrile imines for access to polycyclic spiroindoline derivatives
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作者 Xiaofeng Wang Luorong Yuan +1 位作者 Xiaoping Xu Shunjun Ji 《Green Synthesis and Catalysis》 2023年第2期181-185,共5页
An annulation reaction of tryptamine-derived isocyanides with hydrazonyl chlorides in the presence of bases was developed.Controlled by different bases,[1+2+3]annulation and[1+2+3]/[2+3]annulation cascade were realize... An annulation reaction of tryptamine-derived isocyanides with hydrazonyl chlorides in the presence of bases was developed.Controlled by different bases,[1+2+3]annulation and[1+2+3]/[2+3]annulation cascade were realized.In the latter reaction,five new chemical bonds as well as three new heterocycles were formed in one step.It showed extremely high efficiency,relatively broad substrate scope,milder reaction conditions,good tolerance of functional groups and good chemoselectivity. 展开更多
关键词 3-(2-Isocyanoethyl)indoles Nitrile imines Tetracyclic spiroindolines Pentacyclic bispiroindolines Chemoselective cycloaddition
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Divergent synthesis of chiral amines via Ni-catalyzed chemo-and enantioselective hydrogenation of alkynone imines
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作者 Yuchuan Ma Kai Liu +1 位作者 Lin He Hui Lv 《Science China Chemistry》 SCIE EI CAS CSCD 2023年第11期3186-3192,共7页
Ligand-mediated nickel-catalyzed asymmetric hydrogenation of alkynone imines has been achieved. By using Ni(OAc)_2·4H_2O/(S,S)-Ph-BPE complex as a catalyst, the chemo-and enantioselective hydrogenation of alkynon... Ligand-mediated nickel-catalyzed asymmetric hydrogenation of alkynone imines has been achieved. By using Ni(OAc)_2·4H_2O/(S,S)-Ph-BPE complex as a catalyst, the chemo-and enantioselective hydrogenation of alkynone imines occurred efficiently to afford chiral propargyl amines with high yields and excellent enantioselectivities(up to 99% yield, >99% ee), leaving the readily reducible alkynyl group intact. Both the C=N and C≡C bonds of alkynone imines were hydrogenated efficiently in the presence of Ni(OAc)_2·4H_2O and Josiphos SL-J011-1, furnishing unfunctionalized chiral imines efficiently(up to 99% yield, >99% ee).The(Z)-allylamines and(E)-allylamines were also efficiently prepared from alkynone imines by the combination of the different catalytic systems. The preliminary mechanism study revealed that the reduction of alkynone imines was a stepwise process and the C=N bonds were preferably hydrogenated in the complete reduction of alkynone imines. The synthetic utility of this method was demonstrated by its application in the late-stage modification of the antiviral drug Zidovudine and the concise synthesis of chiral dibenzoazepine. 展开更多
关键词 alkynone imine asymmetric hydrogenation propargyl amine ENANTIOSELECTIVITY chiral amine
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