Heterogeneous metal-catalyzed chemical conversions with a recyclable catalyst are very ideal and challenging for sustainable organic synthesis.A new bipyridyl-Mo(IV)-carbon nitride(CN-K/Mo-Bpy)was prepared by supporti...Heterogeneous metal-catalyzed chemical conversions with a recyclable catalyst are very ideal and challenging for sustainable organic synthesis.A new bipyridyl-Mo(IV)-carbon nitride(CN-K/Mo-Bpy)was prepared by supporting molybdenum complex on C_(3)N_(4)-K and characterized by FT-IR,XRD,SEM,XPS and ICP-OES.Heterogeneous CN–Mo-Bpy catalyst can be applied to the direct amination of nitroarenes and arylboronic acid,thus constructing various valuable diarylamines in high to excellent yields with a wide substrate scope and good functional group tolerance.It is worth noting that this heterogeneous catalyst has high chemical stability and can be recycled for at least five times without reducing its activity.展开更多
The catalytic enantioselective electrophilic amination reaction has emerged as a highly efficient method for synthesizing diverse nitrogen-containing chiral molecules,with the development of various asymmetric catalys...The catalytic enantioselective electrophilic amination reaction has emerged as a highly efficient method for synthesizing diverse nitrogen-containing chiral molecules,with the development of various asymmetric catalysis systems.Chiral phosphoric acids(CPA)have been widely acknowledged as versatile chiral organocatalysts since it was first discovered in 2004,finding application in catalyzing diverse asymmetric reactions.A comprehensive overview of recent advances in CPA-catalyzed asymmetric electrophilic amination reactions using different N-electrophilic reagents,including azo reagents,aryldiazonium salts,and imine derivatives,is presented.Furthermore,insights into future developments in this field are offered.展开更多
A facile method for decarboxylative amination driven by the photoactivity of electron donor-acceptor(EDA)com-plexes assembled from iodide salts and redox-active esters has been proposed.A broad array of acyclic and cy...A facile method for decarboxylative amination driven by the photoactivity of electron donor-acceptor(EDA)com-plexes assembled from iodide salts and redox-active esters has been proposed.A broad array of acyclic and cyclic protected amines were readily synthesized without requiring exogenous transition-metal or photoredox catalysts.Moreover,this ap-proach facilitates late-stage functionalization of complex molecules and is amenable to continuous-flow process on gram scale.展开更多
Gold-catalyzed amination reactions based on azides viaα-imino gold carbene intermediates have attracted extensive attention in the past decades because this methodology leads to the facile and efficient construction ...Gold-catalyzed amination reactions based on azides viaα-imino gold carbene intermediates have attracted extensive attention in the past decades because this methodology leads to the facile and efficient construction of synthetically useful N-containing molecules,especially valuable N-heterocycles.However,successful examples of intermolecular generation ofα-imino gold carbenes by using azides as amination reagents are rarely explored probably due to the weak nucleophilicity of azides.Herein,we disclose an efficient gold-catalyzed intermolecular aminative cyclopropanation of ynamides with the allyl azides,enabling flexible synthesis of a wide range of valuable 3-azabicyclo[3.1.0]hex-2-ene derivatives in good to excellent yields with excellent diastereoselectivities.Importantly,this protocol represents the first use of allyl azide as an efficient amination reagent in gold-catalyzed alkyne amination reactions.展开更多
Synthesis of primary amines from alcohols is an economical and green route to access high-value N-compounds.However,challenges remain to develop both cost-effective and efficient catalysts.In this study,we developed a...Synthesis of primary amines from alcohols is an economical and green route to access high-value N-compounds.However,challenges remain to develop both cost-effective and efficient catalysts.In this study,we developed a Ru-Co/ZrO_(2)single-atom alloy catalyst which afforded diverse primary amines from alcohols in the presence of ammonia and hydrogen with exceptional conversion(up to 90%)and selectivity(80%)under mild conditions(0.7 MPa NH_(3),0.3 MPa H_(2),160℃)and exhibited satisfactory stability upon regeneration.The turnover rate was approximately 8.4 times higher than that observed over the Co/ZrO_(2)catalyst.Characterizations indicated that the alloyed Ru facilitated the reduction of Co,strengthened the interaction with H_(2)and mitigated the over-strong adsorption of aldehyde intermediates.These combined effects contributed significantly to the enhanced catalytic performances.This work presents a promising strategy for the development of advanced catalysts in the amination of alcohols.展开更多
Chiral N-substituted amino amides and esters are ubiquitous scaffolds in pesticides and pharmaceutical chemicals,but their asymmetric synthesis remains challenging especially for those with multiple chiral centers.In ...Chiral N-substituted amino amides and esters are ubiquitous scaffolds in pesticides and pharmaceutical chemicals,but their asymmetric synthesis remains challenging especially for those with multiple chiral centers.In this study,IR104 from Streptomyces aureocirculatus was identified from 157 wild-type imine reductases for the synthesis of(S)-2-((R)-2-oxo-4-propylpyrrolidin-1-yl)butanamide(antiepileptic drug Brivaracetam)via dynamic kinetic resolution reductive amination from ethyl 3-formylhexanoate and(S)-2-aminobutylamide with high diastereoselectivity.To further improve the catalytic efficiency of IR104,its mutant D191E/L195I/E253S/M258A(M3)was identified by saturation mutagenesis and iterative combinatorial mutagenesis,which exhibited a 102-fold increase in the catalytic efficiency relative to that of wild-type enzyme and high diastereoselectivity(98:2 d.r.).Crystal structural analysis and molecular dynamics simulations provided some insights into the molecular basis for the improved activity of the mutant enzyme.The imine reductase identified in this study could accept chiral amino amides/esters as amino donors for the dynamic kinetic resolution reductive amination of racemicα-substituted aldehydo-esters,expanding the substrate scope of imine reductases in the dynamic kinetic resolution-reductive amination.Finally,IR104-M3 was successfully used for the preparation of Brivaracetam at gram scale.Using this mutant,various N-substituted amino amides/esters with two chiral centers were also synthesized with up to 99:1 d.r.and 96%yields and subsequently converted intoγ-andδ-lactams,providing an efficient protocol for the synthesis of these important compounds via enzymatic dynamic kinetic resolution-reductive amination from simple building blocks.展开更多
Primary diamines play an important role in the chemical industry,where they are widely used as raw materials for the manufacture of pharmaceuticals and polymers.Currently,primary diamines are mainly derived from petro...Primary diamines play an important role in the chemical industry,where they are widely used as raw materials for the manufacture of pharmaceuticals and polymers.Currently,primary diamines are mainly derived from petroleum,while harsh or toxic conditions are often needed.Biomass is abundant and renewable,which serves as a promising alternative raw material to produce primary diamines.This review primarily focuses on the synthesis of 2,5-bis(aminomethyl)furan(BAMF),a bio-based diamine with potential as a biomonomer for polyamides and polyureas.Specifically,this review emphasizes the synthesis of BAMF fromthree biomass-derived alcohols and aldehydes,namely 5-hydroxymethylfurfural(HMF),2,5-bis(hydroxymethyl)furan(BHMF),and 2,5-diformylfuran(DFF).These are the key substrates to get BAMF and could be readily obtained from carbohydrates.Even though great effort has been put into the synthesis of BAMF,it remains a tough problem to obtain BAMF with a high yield at a low cost due to the inevitable side reactions,such as unwanted hydrogenation reactions and condensation reactions.Many strategies have been proposed to solve this problem,such as the hydrogen-borrowing strategy and stepwise reductive amination strategy.Herein,we will summarize the key advancements in this area,and discuss the challenges that need to be responded in the future,hoping to provide an insight into the design and development of a more efficient system for the production of biomass-derived diamines.展开更多
Hypercrosslinked polymers(HCPs)with large surface areas,high intrinsic porosities and low production costs may be available platforms for iodine capture.However,the lack of iodine-philicity binding sites limits their ...Hypercrosslinked polymers(HCPs)with large surface areas,high intrinsic porosities and low production costs may be available platforms for iodine capture.However,the lack of iodine-philicity binding sites limits their adsorption capacity.Here we use vapor-phase postsynthetic amination strategy to introduce electron-donating amino groups into the prefabricated HCPs for enhancing their iodine capture performance.Through simple vapor-phase exposure,the halogen-containing HCPs can be grafted by amines through nucleophilic substitution toward chloro groups.Combining with the abundant amino groups and high porosities,the amino-functionalized porous polymers show substantially increased iodine adsorption capacity,about 221%as that of original one,accompanied by excellent recyclability.Mechanism investigations reveal the key roles of the electron-donor amino groups andπ-conjugated benzene rings along with structure characteristics of porous polymer frameworks in iodine capture.Moreover,this vapor-phase amination strategy shows good generality and can be extended to various amines,e.g.,ethylenediamine,1,3-diaminopropane and diethylenetriamine.Our work proves that this simple vapor-phase postsynthetic functionalization strategy may be applied in other porous polymers with wide application prospects in adsorption,separation and storage.展开更多
The first example of sono-photocatalytic bond formation was reported.With both visible light and ultrasound wave as the energy,various 3-aminoquinoxalin-2(1H)-ones were efficiently obtained with good functional group ...The first example of sono-photocatalytic bond formation was reported.With both visible light and ultrasound wave as the energy,various 3-aminoquinoxalin-2(1H)-ones were efficiently obtained with good functional group tolerance in the absence of any additive or external photocatalyst.Compared with the conventional photocatalysis,sono-photocatalysis not only dramatically improved the reaction rates and yields,but also reduced energy consumption.展开更多
An optimization study on the amination reaction of epoxy polyisobutylene for synthesis of polyisobutylene amine is presented. The experimental results indicate that n-butanol and ethylenediamine are the suitable solve...An optimization study on the amination reaction of epoxy polyisobutylene for synthesis of polyisobutylene amine is presented. The experimental results indicate that n-butanol and ethylenediamine are the suitable solvent and amination agents for the reaction, respectively. The reaction yield of the amination reaction is notably increased with the enhanced molar ratio of either n-butanol against epoxy polyisobutylene or ethylenediamine against epoxy polyisobutylene. Also, the yield is enhanced with increasing temperature and time during the experimental range. Strikingly, the yield reaches as high as 91. 30% under optimal conditions; with the molar ratio of ethylenediamine, n-butanol and PIBO of 10∶ 6∶ 1, the reaction temperature of 150 ℃ and the reaction time of 6 h. In addition, the yield of the reaction is slightly decreased with the enhanced water content of the system. Accordingly, the mass concentration of water should be controlled within 1. 7% during the reaction.展开更多
SAPO-34 was synthesized with n-butylamine（BA） as a template for the first time.Crystallization temperature and initial Si amount were important factors leading to successful syntheses.Lamellar AlPO-kanemite tends to...SAPO-34 was synthesized with n-butylamine（BA） as a template for the first time.Crystallization temperature and initial Si amount were important factors leading to successful syntheses.Lamellar AlPO-kanemite tends to form as the major phase or as an impurity of SAPO-34 at lower crystallization temperatures,though a higher initial Si amount may offer a positive effect on the crystallization of SAPO-34 that mitigates the low temperature.Higher temperature（240℃） can effectively suppress the generation of lamellar materials and allow the synthesis of pure SAPO-34 with a wider range of Si incorporation.The crystallization processes at 200 and 240℃ were investigated and compared.We used the aminothermal method to synthesize SAPO-34-BA at 240℃ and also found n-propylamine is a suitable template for the synthesis of SAPO-34.The SAPO-34-BA products were characterized by many techniques.SAPO-34-BA has good thermal stability,crystallinity and porosity.BA remained intact in the crystals with ~1.8 BA molecule per chabazite cage.The catalytic performance of SAPO-34 was tested in the methanol amination reaction,which showed high methanol conversion and selectivity for methylamine plus dimethylamine under the conditions investigated,suggesting that this material is a good candidate for the synthesis of methylamines.展开更多
Ni-Re/SiO2 catalysts with controllable Ni particle sizes(4.5–18.0 nm)were synthesized to investigate the effects of the particle size on the amination of monoethanolamine(MEA).The catalysts were characterized by vari...Ni-Re/SiO2 catalysts with controllable Ni particle sizes(4.5–18.0 nm)were synthesized to investigate the effects of the particle size on the amination of monoethanolamine(MEA).The catalysts were characterized by various techniques and evaluated for the amination reaction in a trickle bed reactor at 170℃,8.0 MPa,and 0.5 h^-1 liquid hourly space velocity of MEA(LHSVMEA)in NH3/H2 atmosphere.The Ni-Re/SiO2 catalyst with the lowest Ni particle size(4.5 nm)exhibited the highest yield(66.4%)of the desired amines(ethylenediamine(EDA)and piperazine(PIP)).The results of the analysis show that the turnover frequency of MEA increased slightly(from 193 to 253 h^-1)as the Ni particle sizes of the Ni-Re/SiO2 catalysts increased from 4.5 to 18.0 nm.Moreover,the product distribution could be adjusted by varying the Ni particle size.The ratio of primary to secondary amines increased from 1.0 to 2.0 upon increasing the Ni particle size from 4.5 to 18.0 nm.Further analyses reveal that the Ni particle size influenced the electronic properties of surface Ni,which in turn affected the adsorption of MEA and the reaction pathway of MEA amination.Compared to those of small Ni particles,large particles possessed a higher proportion of high-coordinated terrace Ni sites and a higher surface electron density,which favored the amination of MEA and NH3 to form EDA.展开更多
A shaped binderless and two binder‐containing ZSM‐11 zeolite catalysts were prepared and characterized by powder X‐ray diffraction, N2 adsorption‐desorption, and pyridine adsorption‐infrared measurements. The bin...A shaped binderless and two binder‐containing ZSM‐11 zeolite catalysts were prepared and characterized by powder X‐ray diffraction, N2 adsorption‐desorption, and pyridine adsorption‐infrared measurements. The binderless catalyst was synthesized using a dry‐gel conversion technique, inwhich 1,6‐hexanediamine and tetrabutylammonium bromide were used as structure‐directingagents and no other alkaline materials were added. The catalytic performance of the zeolites in the direct amination of isobutene to tert‐butylamine was evaluated in a fixed‐bed reactor. By virtue of its high crystallinity as well as its good mechanical strength, the shaped binderless ZSM‐11 catalyst showed a higher rate of formation of tert‐butylamine than did the binder‐containing catalysts.展开更多
A novel tandem reductive amination/intermolecular nucleophilic aromatic substitution (SNAr) sequence has been established for the synthesis of amine containing pyrimidine in formation of one carbon-oxygen and one carb...A novel tandem reductive amination/intermolecular nucleophilic aromatic substitution (SNAr) sequence has been established for the synthesis of amine containing pyrimidine in formation of one carbon-oxygen and one carbon-nitrogen bonds in a one-pot fashion. Treatment of aldehyde with arylamine, 2-methanesulfonyl-4,6-dimeth-oxypyrimidine and sodium borohydride provides good overall yield. The p-toluenesulfonic acid (PTSA) can be used as activator and is generally needed in the reaction. Dioxane is the preferred reaction solvent, but reactions can also be carried out in tetrahydrofuran (THF), MeCN, toluene and dichloromethane. The procedure is carried out effectively in the presence of K2CO3. The reaction proceeds smoothly with aromatic aldehydes and arylamines possessing elec-tron-donating or-withdrawing groups. This method can be applied to the synthesis of the oilseed rape herbicide and is superior to the classical one in several aspects: cutting out several purification steps, minimizing solvent use and chemical waste, and saving time. Its advantages such as operational convenience, high-efficient synthesis, and starting material availability make it a desirable method for preparing amines with molecular diversity and biological activity.展开更多
On basis of thermodynamic empirical equations, the thermodynamic parameters for the direct amination of isobutylene to tert‐butylamine, an atomically economic and green chemical reaction,were calculated. In particula...On basis of thermodynamic empirical equations, the thermodynamic parameters for the direct amination of isobutylene to tert‐butylamine, an atomically economic and green chemical reaction,were calculated. In particular, the equilibrium conversion of isobutylene under various reactionconditions close to those used in industry was calculated and discussed. Isobutylene amination is atemperature sensitive reaction due to its exothermic nature and isobutylene equilibrium conversiondecreases with temperature. However, kinetically, the amination reaction will be faster at ahigher temperature. Thus, there must be an optimum temperature for the reaction. A high pressureand n(NH3)/n(i‐C4H8) molar ratio promote the transformation of isobutylene to tert‐butylamine.Developing a highly efficient catalyst under mild reaction conditions is preferred for the aminationprocess. The reaction was investigated over a series of acidic zeolites. ZSM‐11 zeolite exhibited thebest performance with 14.2% isobutylene conversion (52.2% of the equilibrium conversion) and >99.0% tert‐butylamine selectivity. The effect of reaction conditions on the performance of the ZSM‐11 catalyst agreed with the thermodynamic results, which provides guidance for further catalyst development and reaction condition optimization.展开更多
Selective reductive amination of carbonyl compounds with high activity is very essential for the chemical and pharmaceutical industry,but scarcely successful paradigm was reported via efficient photocatalytic reaction...Selective reductive amination of carbonyl compounds with high activity is very essential for the chemical and pharmaceutical industry,but scarcely successful paradigm was reported via efficient photocatalytic reactions.Herein,the ultrasmall Ru nanoclusters(~0.9 nm)were successfully fabricated over P25 support with positive charged Ru^(δ+)species at the interface.A new route was developed to achieve the furfural(FAL)to furfurylamine(FAM)by coupling the light-driven reductive amination and hydrogen transfer of ethanol over this type catalyst.Strikingly,the photocatalytic activity and selectivity are strongly dependent on the particle size and electronic structure of Ruthenium.The Ru^(δ+)species at the interface promote the formation of active imine intermediates;moreover,the Ru nanoclusters facilitate the separation efficiency of electrons and holes as well as accelerate the further hydrogenation of imine intermediates to product primary amines.In contrast Ru particles in larger nanometer size facilitate the formation of the furfuryl alcohol and excessive hydrogenation products.In addition,the coupling byproducts can be effectively inhibited via the construction of sub-nanocluster.This study offers a new path to produce the primary amines from biomass-derived carbonyl compounds over hybrid semiconductor/metal-clusters photocatalyst via light-driven tandem catalytic process.展开更多
In this work, the amination of sulfonated polystyrene resin with alkyl secondary amine is investigated. The catalytic activities of the modified resins are determined through the hydration of l-butene. The optimum cha...In this work, the amination of sulfonated polystyrene resin with alkyl secondary amine is investigated. The catalytic activities of the modified resins are determined through the hydration of l-butene. The optimum chain length and the best range of amination rate are determined. It is found that the single-pass conversion of 1 -butene was raised 2% on average, and the relative activity was increased over 30% after modification. A hypothesis about the enhancement of catalytic activities by the inclusion of alkyl chain to wrap up the butene molecule is proposed.展开更多
The atomically economic and green chemical reaction of direct amination of isobutylene to tertbutylamine, particularly under the relative mild reaction conditions available for future industrial use,was carried out ov...The atomically economic and green chemical reaction of direct amination of isobutylene to tertbutylamine, particularly under the relative mild reaction conditions available for future industrial use,was carried out over zeolite catalysts possessing different topological structures, from one dimensional to three dimensional pore system, and from small 8-member ring pore（MRP） to medium 10 MRP and further to large 12 MRP zeolites, to disclose the relationship between the zeolite properties/topologies and their amination performance systematically under the mild reaction conditions. It was discovered that the pore structure and the acidities of zeolite catalysts played crucial roles in the isobutylene amination process, and suitable pore diameter（larger than 0.5 nm or with large side pockets/cups in the outside surface） and a certain number of mid-strong acid sites are indispensable to catalyze the amination reaction,while too strong acid strength was not conducive to the process of isobutylene amination. Among them,zeolites with topologies of BEA, MFI, MEL, MWW and EUO exhibited good amination performance, with which the isobutylene conversion was higher than 12.61%（>46.42% of the equilibrium conversion） under the studied mild reaction conditions. Due to the good amination performance and the large adjustable Si/Al;ratio range, ZSM-5 was selected to further study the effect of acidity on the amination performance systematically under the mild reaction conditions, and the activity-acidity relationship in the amination process was disclosed: the amination activity（isobutylene conversion） had a linear correlation with the amount of mid-strong B acidity under the studied conditions over ZSM-5 catalyst, which can provide guidance for further developing high-efficient amination catalyst under mild reaction conditions available for future industrial use.展开更多
The direct reductive amination of 2,5-diformylfuran (DFF) with ammonia to 2,5-bis(aminomethyl)furan (BAF) was demonstrated, for the first time, over the commercial type Nickel-Raney and acid treated Nickel-Raney catal...The direct reductive amination of 2,5-diformylfuran (DFF) with ammonia to 2,5-bis(aminomethyl)furan (BAF) was demonstrated, for the first time, over the commercial type Nickel-Raney and acid treated Nickel-Raney catalysts. The effects of reaction parameters such as reaction medium, temperature and hydrogen pressure were described. The acid treated Nickel-Raney catalyst exhibited the highest BAF yield in the THF-water mixed reaction medium. The relatively higher Ni0 species composition and larger surface area of the acid treated Nickel-Raney catalyst with specific reaction conditions contributed greatly to the BAF formation. The oligomeric species, such as furanic imine trimers and tetramers confirmed by MALDI-MS analysis were presented as the intermediates of DFF reductive amination.展开更多
Copper-catalyzed synthesis of N-aryl anthranilic acid derivatives using effective amination of 2-chloro and 2-bromobenzoic acid under microwave irradiation is reported. Some of the advantages of this method are high c...Copper-catalyzed synthesis of N-aryl anthranilic acid derivatives using effective amination of 2-chloro and 2-bromobenzoic acid under microwave irradiation is reported. Some of the advantages of this method are high chemoselectivity, short reaction times, ease of work up procedure and elimination of the need for acid protection. 2009 Published by Elsevier B.V. on behalf of Chinese Chemical Society.展开更多
基金support for this work by Hebei Education Department(No.JZX2024004)Central Guidance on Local Science and Technology Development Fund of Hebei Province(No.236Z1404G)+3 种基金the National Natural Science Foundation of China(Nos.22301060 and 21272053)China Postdoctoral Science Foundation(No.2023M730914)the Natural Science Foundation of Hebei Province(Biopharmaceutical Joint Fund No.B2022206008)Project of Science and Technology Department of Hebei Province(No.22567622H)。
文摘Heterogeneous metal-catalyzed chemical conversions with a recyclable catalyst are very ideal and challenging for sustainable organic synthesis.A new bipyridyl-Mo(IV)-carbon nitride(CN-K/Mo-Bpy)was prepared by supporting molybdenum complex on C_(3)N_(4)-K and characterized by FT-IR,XRD,SEM,XPS and ICP-OES.Heterogeneous CN–Mo-Bpy catalyst can be applied to the direct amination of nitroarenes and arylboronic acid,thus constructing various valuable diarylamines in high to excellent yields with a wide substrate scope and good functional group tolerance.It is worth noting that this heterogeneous catalyst has high chemical stability and can be recycled for at least five times without reducing its activity.
文摘The catalytic enantioselective electrophilic amination reaction has emerged as a highly efficient method for synthesizing diverse nitrogen-containing chiral molecules,with the development of various asymmetric catalysis systems.Chiral phosphoric acids(CPA)have been widely acknowledged as versatile chiral organocatalysts since it was first discovered in 2004,finding application in catalyzing diverse asymmetric reactions.A comprehensive overview of recent advances in CPA-catalyzed asymmetric electrophilic amination reactions using different N-electrophilic reagents,including azo reagents,aryldiazonium salts,and imine derivatives,is presented.Furthermore,insights into future developments in this field are offered.
文摘A facile method for decarboxylative amination driven by the photoactivity of electron donor-acceptor(EDA)com-plexes assembled from iodide salts and redox-active esters has been proposed.A broad array of acyclic and cyclic protected amines were readily synthesized without requiring exogenous transition-metal or photoredox catalysts.Moreover,this ap-proach facilitates late-stage functionalization of complex molecules and is amenable to continuous-flow process on gram scale.
基金financial support from the National Natural Science Foundation of China(Nos.22125108,22331004 and 22121001)Yunnan Normal University,Applied Basic Research Projects of Yunnan Province(No.202101AT070217)+1 种基金the Jiangxi Provincial Natural Science Foundation(No.20224BAB213013)the Jiangxi Provincial Department of Education in Science and Technology Program Project(No.GJJ210906)。
文摘Gold-catalyzed amination reactions based on azides viaα-imino gold carbene intermediates have attracted extensive attention in the past decades because this methodology leads to the facile and efficient construction of synthetically useful N-containing molecules,especially valuable N-heterocycles.However,successful examples of intermolecular generation ofα-imino gold carbenes by using azides as amination reagents are rarely explored probably due to the weak nucleophilicity of azides.Herein,we disclose an efficient gold-catalyzed intermolecular aminative cyclopropanation of ynamides with the allyl azides,enabling flexible synthesis of a wide range of valuable 3-azabicyclo[3.1.0]hex-2-ene derivatives in good to excellent yields with excellent diastereoselectivities.Importantly,this protocol represents the first use of allyl azide as an efficient amination reagent in gold-catalyzed alkyne amination reactions.
文摘Synthesis of primary amines from alcohols is an economical and green route to access high-value N-compounds.However,challenges remain to develop both cost-effective and efficient catalysts.In this study,we developed a Ru-Co/ZrO_(2)single-atom alloy catalyst which afforded diverse primary amines from alcohols in the presence of ammonia and hydrogen with exceptional conversion(up to 90%)and selectivity(80%)under mild conditions(0.7 MPa NH_(3),0.3 MPa H_(2),160℃)and exhibited satisfactory stability upon regeneration.The turnover rate was approximately 8.4 times higher than that observed over the Co/ZrO_(2)catalyst.Characterizations indicated that the alloyed Ru facilitated the reduction of Co,strengthened the interaction with H_(2)and mitigated the over-strong adsorption of aldehyde intermediates.These combined effects contributed significantly to the enhanced catalytic performances.This work presents a promising strategy for the development of advanced catalysts in the amination of alcohols.
文摘Chiral N-substituted amino amides and esters are ubiquitous scaffolds in pesticides and pharmaceutical chemicals,but their asymmetric synthesis remains challenging especially for those with multiple chiral centers.In this study,IR104 from Streptomyces aureocirculatus was identified from 157 wild-type imine reductases for the synthesis of(S)-2-((R)-2-oxo-4-propylpyrrolidin-1-yl)butanamide(antiepileptic drug Brivaracetam)via dynamic kinetic resolution reductive amination from ethyl 3-formylhexanoate and(S)-2-aminobutylamide with high diastereoselectivity.To further improve the catalytic efficiency of IR104,its mutant D191E/L195I/E253S/M258A(M3)was identified by saturation mutagenesis and iterative combinatorial mutagenesis,which exhibited a 102-fold increase in the catalytic efficiency relative to that of wild-type enzyme and high diastereoselectivity(98:2 d.r.).Crystal structural analysis and molecular dynamics simulations provided some insights into the molecular basis for the improved activity of the mutant enzyme.The imine reductase identified in this study could accept chiral amino amides/esters as amino donors for the dynamic kinetic resolution reductive amination of racemicα-substituted aldehydo-esters,expanding the substrate scope of imine reductases in the dynamic kinetic resolution-reductive amination.Finally,IR104-M3 was successfully used for the preparation of Brivaracetam at gram scale.Using this mutant,various N-substituted amino amides/esters with two chiral centers were also synthesized with up to 99:1 d.r.and 96%yields and subsequently converted intoγ-andδ-lactams,providing an efficient protocol for the synthesis of these important compounds via enzymatic dynamic kinetic resolution-reductive amination from simple building blocks.
基金financially supported by China Scholarship Council,Science and Technology Project of the State Administration for Market Regulation(2022MK111)the Fundamental Research Funds for the Central Universities.
文摘Primary diamines play an important role in the chemical industry,where they are widely used as raw materials for the manufacture of pharmaceuticals and polymers.Currently,primary diamines are mainly derived from petroleum,while harsh or toxic conditions are often needed.Biomass is abundant and renewable,which serves as a promising alternative raw material to produce primary diamines.This review primarily focuses on the synthesis of 2,5-bis(aminomethyl)furan(BAMF),a bio-based diamine with potential as a biomonomer for polyamides and polyureas.Specifically,this review emphasizes the synthesis of BAMF fromthree biomass-derived alcohols and aldehydes,namely 5-hydroxymethylfurfural(HMF),2,5-bis(hydroxymethyl)furan(BHMF),and 2,5-diformylfuran(DFF).These are the key substrates to get BAMF and could be readily obtained from carbohydrates.Even though great effort has been put into the synthesis of BAMF,it remains a tough problem to obtain BAMF with a high yield at a low cost due to the inevitable side reactions,such as unwanted hydrogenation reactions and condensation reactions.Many strategies have been proposed to solve this problem,such as the hydrogen-borrowing strategy and stepwise reductive amination strategy.Herein,we will summarize the key advancements in this area,and discuss the challenges that need to be responded in the future,hoping to provide an insight into the design and development of a more efficient system for the production of biomass-derived diamines.
基金financially supported by National Natural Science Foundation of China(No.22178143)Guangdong Basic and Applied Basic Research Foundation(Nos.2021A1515110365 and2020B1515120036)+3 种基金Natural Science Foundation of Anhui Higher Education Institutions(No.2023AH050168)Innovation and Entrepreneurship Training Program for China College Students(No.202310878049)Director Foundation of Anhui Province Engineering Laboratory of Advanced Building Materials(No.JZCL2305ZR)Ph.D.Startup Foundation of Anhui Jianzhu University(No.2023QDZ34)。
文摘Hypercrosslinked polymers(HCPs)with large surface areas,high intrinsic porosities and low production costs may be available platforms for iodine capture.However,the lack of iodine-philicity binding sites limits their adsorption capacity.Here we use vapor-phase postsynthetic amination strategy to introduce electron-donating amino groups into the prefabricated HCPs for enhancing their iodine capture performance.Through simple vapor-phase exposure,the halogen-containing HCPs can be grafted by amines through nucleophilic substitution toward chloro groups.Combining with the abundant amino groups and high porosities,the amino-functionalized porous polymers show substantially increased iodine adsorption capacity,about 221%as that of original one,accompanied by excellent recyclability.Mechanism investigations reveal the key roles of the electron-donor amino groups andπ-conjugated benzene rings along with structure characteristics of porous polymer frameworks in iodine capture.Moreover,this vapor-phase amination strategy shows good generality and can be extended to various amines,e.g.,ethylenediamine,1,3-diaminopropane and diethylenetriamine.Our work proves that this simple vapor-phase postsynthetic functionalization strategy may be applied in other porous polymers with wide application prospects in adsorption,separation and storage.
基金financial support from the University of South China。
文摘The first example of sono-photocatalytic bond formation was reported.With both visible light and ultrasound wave as the energy,various 3-aminoquinoxalin-2(1H)-ones were efficiently obtained with good functional group tolerance in the absence of any additive or external photocatalyst.Compared with the conventional photocatalysis,sono-photocatalysis not only dramatically improved the reaction rates and yields,but also reduced energy consumption.
基金The Natural Science Foundation of Jiangsu Province(No.BK20130602)the Project of the Collaborative Innovation Center of Suzhou Nano Science and Technology
文摘An optimization study on the amination reaction of epoxy polyisobutylene for synthesis of polyisobutylene amine is presented. The experimental results indicate that n-butanol and ethylenediamine are the suitable solvent and amination agents for the reaction, respectively. The reaction yield of the amination reaction is notably increased with the enhanced molar ratio of either n-butanol against epoxy polyisobutylene or ethylenediamine against epoxy polyisobutylene. Also, the yield is enhanced with increasing temperature and time during the experimental range. Strikingly, the yield reaches as high as 91. 30% under optimal conditions; with the molar ratio of ethylenediamine, n-butanol and PIBO of 10∶ 6∶ 1, the reaction temperature of 150 ℃ and the reaction time of 6 h. In addition, the yield of the reaction is slightly decreased with the enhanced water content of the system. Accordingly, the mass concentration of water should be controlled within 1. 7% during the reaction.
基金supported by the National Natural Science Foundation of China(21676262,21476228,21506207)the Key Research Program of Frontier Sciences of CAS(QYZDB-SSW-JSC040)~~
文摘SAPO-34 was synthesized with n-butylamine（BA） as a template for the first time.Crystallization temperature and initial Si amount were important factors leading to successful syntheses.Lamellar AlPO-kanemite tends to form as the major phase or as an impurity of SAPO-34 at lower crystallization temperatures,though a higher initial Si amount may offer a positive effect on the crystallization of SAPO-34 that mitigates the low temperature.Higher temperature（240℃） can effectively suppress the generation of lamellar materials and allow the synthesis of pure SAPO-34 with a wider range of Si incorporation.The crystallization processes at 200 and 240℃ were investigated and compared.We used the aminothermal method to synthesize SAPO-34-BA at 240℃ and also found n-propylamine is a suitable template for the synthesis of SAPO-34.The SAPO-34-BA products were characterized by many techniques.SAPO-34-BA has good thermal stability,crystallinity and porosity.BA remained intact in the crystals with ~1.8 BA molecule per chabazite cage.The catalytic performance of SAPO-34 was tested in the methanol amination reaction,which showed high methanol conversion and selectivity for methylamine plus dimethylamine under the conditions investigated,suggesting that this material is a good candidate for the synthesis of methylamines.
基金supported by the National Natural Science Foundation of China(21273227)Strategic Priority Research Program of Chinese Academy of Sciences(XDB17000000)~~
文摘Ni-Re/SiO2 catalysts with controllable Ni particle sizes(4.5–18.0 nm)were synthesized to investigate the effects of the particle size on the amination of monoethanolamine(MEA).The catalysts were characterized by various techniques and evaluated for the amination reaction in a trickle bed reactor at 170℃,8.0 MPa,and 0.5 h^-1 liquid hourly space velocity of MEA(LHSVMEA)in NH3/H2 atmosphere.The Ni-Re/SiO2 catalyst with the lowest Ni particle size(4.5 nm)exhibited the highest yield(66.4%)of the desired amines(ethylenediamine(EDA)and piperazine(PIP)).The results of the analysis show that the turnover frequency of MEA increased slightly(from 193 to 253 h^-1)as the Ni particle sizes of the Ni-Re/SiO2 catalysts increased from 4.5 to 18.0 nm.Moreover,the product distribution could be adjusted by varying the Ni particle size.The ratio of primary to secondary amines increased from 1.0 to 2.0 upon increasing the Ni particle size from 4.5 to 18.0 nm.Further analyses reveal that the Ni particle size influenced the electronic properties of surface Ni,which in turn affected the adsorption of MEA and the reaction pathway of MEA amination.Compared to those of small Ni particles,large particles possessed a higher proportion of high-coordinated terrace Ni sites and a higher surface electron density,which favored the amination of MEA and NH3 to form EDA.
基金supported by K.C.Wong Education Foundation, Hong Kong (201611)Youth Innovation Promotion Association, CAS (20120155)~~
文摘A shaped binderless and two binder‐containing ZSM‐11 zeolite catalysts were prepared and characterized by powder X‐ray diffraction, N2 adsorption‐desorption, and pyridine adsorption‐infrared measurements. The binderless catalyst was synthesized using a dry‐gel conversion technique, inwhich 1,6‐hexanediamine and tetrabutylammonium bromide were used as structure‐directingagents and no other alkaline materials were added. The catalytic performance of the zeolites in the direct amination of isobutene to tert‐butylamine was evaluated in a fixed‐bed reactor. By virtue of its high crystallinity as well as its good mechanical strength, the shaped binderless ZSM‐11 catalyst showed a higher rate of formation of tert‐butylamine than did the binder‐containing catalysts.
基金Project (Nos. Y407118 and D3080282) supported by the Natural Science Foundation of Zhejiang Province, China
文摘A novel tandem reductive amination/intermolecular nucleophilic aromatic substitution (SNAr) sequence has been established for the synthesis of amine containing pyrimidine in formation of one carbon-oxygen and one carbon-nitrogen bonds in a one-pot fashion. Treatment of aldehyde with arylamine, 2-methanesulfonyl-4,6-dimeth-oxypyrimidine and sodium borohydride provides good overall yield. The p-toluenesulfonic acid (PTSA) can be used as activator and is generally needed in the reaction. Dioxane is the preferred reaction solvent, but reactions can also be carried out in tetrahydrofuran (THF), MeCN, toluene and dichloromethane. The procedure is carried out effectively in the presence of K2CO3. The reaction proceeds smoothly with aromatic aldehydes and arylamines possessing elec-tron-donating or-withdrawing groups. This method can be applied to the synthesis of the oilseed rape herbicide and is superior to the classical one in several aspects: cutting out several purification steps, minimizing solvent use and chemical waste, and saving time. Its advantages such as operational convenience, high-efficient synthesis, and starting material availability make it a desirable method for preparing amines with molecular diversity and biological activity.
基金supported by K. C. Wong Education FoundationYouth Innovation Promotion Association of CAS (20120155)Dalian Eminent Young Scientist Program (2015R009)~~
文摘On basis of thermodynamic empirical equations, the thermodynamic parameters for the direct amination of isobutylene to tert‐butylamine, an atomically economic and green chemical reaction,were calculated. In particular, the equilibrium conversion of isobutylene under various reactionconditions close to those used in industry was calculated and discussed. Isobutylene amination is atemperature sensitive reaction due to its exothermic nature and isobutylene equilibrium conversiondecreases with temperature. However, kinetically, the amination reaction will be faster at ahigher temperature. Thus, there must be an optimum temperature for the reaction. A high pressureand n(NH3)/n(i‐C4H8) molar ratio promote the transformation of isobutylene to tert‐butylamine.Developing a highly efficient catalyst under mild reaction conditions is preferred for the aminationprocess. The reaction was investigated over a series of acidic zeolites. ZSM‐11 zeolite exhibited thebest performance with 14.2% isobutylene conversion (52.2% of the equilibrium conversion) and >99.0% tert‐butylamine selectivity. The effect of reaction conditions on the performance of the ZSM‐11 catalyst agreed with the thermodynamic results, which provides guidance for further catalyst development and reaction condition optimization.
基金financially supported by the National Natural Science Foundation of China(202102007,21978147 and 21935001)the Fundamental Research Funds for the Central Universities(buctrc202112)。
文摘Selective reductive amination of carbonyl compounds with high activity is very essential for the chemical and pharmaceutical industry,but scarcely successful paradigm was reported via efficient photocatalytic reactions.Herein,the ultrasmall Ru nanoclusters(~0.9 nm)were successfully fabricated over P25 support with positive charged Ru^(δ+)species at the interface.A new route was developed to achieve the furfural(FAL)to furfurylamine(FAM)by coupling the light-driven reductive amination and hydrogen transfer of ethanol over this type catalyst.Strikingly,the photocatalytic activity and selectivity are strongly dependent on the particle size and electronic structure of Ruthenium.The Ru^(δ+)species at the interface promote the formation of active imine intermediates;moreover,the Ru nanoclusters facilitate the separation efficiency of electrons and holes as well as accelerate the further hydrogenation of imine intermediates to product primary amines.In contrast Ru particles in larger nanometer size facilitate the formation of the furfuryl alcohol and excessive hydrogenation products.In addition,the coupling byproducts can be effectively inhibited via the construction of sub-nanocluster.This study offers a new path to produce the primary amines from biomass-derived carbonyl compounds over hybrid semiconductor/metal-clusters photocatalyst via light-driven tandem catalytic process.
文摘In this work, the amination of sulfonated polystyrene resin with alkyl secondary amine is investigated. The catalytic activities of the modified resins are determined through the hydration of l-butene. The optimum chain length and the best range of amination rate are determined. It is found that the single-pass conversion of 1 -butene was raised 2% on average, and the relative activity was increased over 30% after modification. A hypothesis about the enhancement of catalytic activities by the inclusion of alkyl chain to wrap up the butene molecule is proposed.
基金the financial support of K.C.Wong Education FoundationDalian Eminent Young Scientist Program(2015R009)
文摘The atomically economic and green chemical reaction of direct amination of isobutylene to tertbutylamine, particularly under the relative mild reaction conditions available for future industrial use,was carried out over zeolite catalysts possessing different topological structures, from one dimensional to three dimensional pore system, and from small 8-member ring pore（MRP） to medium 10 MRP and further to large 12 MRP zeolites, to disclose the relationship between the zeolite properties/topologies and their amination performance systematically under the mild reaction conditions. It was discovered that the pore structure and the acidities of zeolite catalysts played crucial roles in the isobutylene amination process, and suitable pore diameter（larger than 0.5 nm or with large side pockets/cups in the outside surface） and a certain number of mid-strong acid sites are indispensable to catalyze the amination reaction,while too strong acid strength was not conducive to the process of isobutylene amination. Among them,zeolites with topologies of BEA, MFI, MEL, MWW and EUO exhibited good amination performance, with which the isobutylene conversion was higher than 12.61%（>46.42% of the equilibrium conversion） under the studied mild reaction conditions. Due to the good amination performance and the large adjustable Si/Al;ratio range, ZSM-5 was selected to further study the effect of acidity on the amination performance systematically under the mild reaction conditions, and the activity-acidity relationship in the amination process was disclosed: the amination activity（isobutylene conversion） had a linear correlation with the amount of mid-strong B acidity under the studied conditions over ZSM-5 catalyst, which can provide guidance for further developing high-efficient amination catalyst under mild reaction conditions available for future industrial use.
文摘The direct reductive amination of 2,5-diformylfuran (DFF) with ammonia to 2,5-bis(aminomethyl)furan (BAF) was demonstrated, for the first time, over the commercial type Nickel-Raney and acid treated Nickel-Raney catalysts. The effects of reaction parameters such as reaction medium, temperature and hydrogen pressure were described. The acid treated Nickel-Raney catalyst exhibited the highest BAF yield in the THF-water mixed reaction medium. The relatively higher Ni0 species composition and larger surface area of the acid treated Nickel-Raney catalyst with specific reaction conditions contributed greatly to the BAF formation. The oligomeric species, such as furanic imine trimers and tetramers confirmed by MALDI-MS analysis were presented as the intermediates of DFF reductive amination.
基金the financial support of this work by the Research Council of Mazandaran University.
文摘Copper-catalyzed synthesis of N-aryl anthranilic acid derivatives using effective amination of 2-chloro and 2-bromobenzoic acid under microwave irradiation is reported. Some of the advantages of this method are high chemoselectivity, short reaction times, ease of work up procedure and elimination of the need for acid protection. 2009 Published by Elsevier B.V. on behalf of Chinese Chemical Society.
