A new palladium-catalyzed selective aminomethylation of conjugated 1,3-dienes with aminais via double C-N bond activation is described. This simple method provides an effective and rapid approach for the synthesis of ...A new palladium-catalyzed selective aminomethylation of conjugated 1,3-dienes with aminais via double C-N bond activation is described. This simple method provides an effective and rapid approach for the synthesis of linear a,13-unsaturated allylic amines with perfect regioselectivity. Mechanistic studies disclosed that one palladium catalyst cleaved two distinct C-N bond to furnish a cascade double C-N bond activation, in which an allylic 1,3-diamine and allylic 1,2-diamine were initially formed as key intermediates through the palladium-catalyzed C-N bond activation of aminal and the α,β-unsaturated allylic amine was subsequently produced via palladium-catalyzed C-N bond activation of the allylic diamines.展开更多
Chiral amines are synthetically versatile intermedi-ates used for the preparation of a wide range of biologically active compounds and drugs.Compared with the well-developed synthesis ofα-stereogenic amines,the estab...Chiral amines are synthetically versatile intermedi-ates used for the preparation of a wide range of biologically active compounds and drugs.Compared with the well-developed synthesis ofα-stereogenic amines,the establishment of enantioselective protocols to accessβ-stereogenic amines are very limited.展开更多
Main observation and conclusion A new strategy for the generation of the active Pd-alkyl species from aminal via C-N bond activation has been established,in which the formation of zwitterionic intermediate through aza...Main observation and conclusion A new strategy for the generation of the active Pd-alkyl species from aminal via C-N bond activation has been established,in which the formation of zwitterionic intermediate through aza-Michael addition of aminal to nitrodienes or dienones is identified as a key step for the activation of the C-N bond.The efficient strategy has enabled a new palladium-catalyzed a-aminomethylation of nitro-dienes and dienones via double C-N bond activation.The scope and versatility of the reaction were demonstrated and a broad range of substrates bearing electron-donating and-withdrawing groups on the aromatic rings were all compatible with this reaction to furnish the desired a-aminomethylated products in moderate to good yields with excellent regioselectivities and E/Z selectivities.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
The regioselective Mannich-type aminomethylation of hydroquinone afforded a nitrogen-containing compound, 2,5-bis-(morpholinomethyl)hydroquinone A, and its crystal structure was determined by single-crystal X-ray di...The regioselective Mannich-type aminomethylation of hydroquinone afforded a nitrogen-containing compound, 2,5-bis-(morpholinomethyl)hydroquinone A, and its crystal structure was determined by single-crystal X-ray diffraction. Crystal data for A: C16H24N2O4, Mr = 308.37, orthorhombic, space group Pbca, a = 10.479(4), b = 10.298(4), c = 14.865(5) ?, V = 1604.3(11) ?3, Z = 4, Dc = 1.277 g/cm3, F(000) = 664, μ = 0.092 mm-1, GOF = 1.078, the final R = 0.0508 and wR = 0.1075 for 1416 observed reflections with I > 2σ(I). There exist two intramolecular O–H…N hy- drogen bonds between the phenolic O atoms and the morpholine N donors and the morpholino rings assume the preferred chair conformation.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
The first example of TBAI/H_(2)O cooperative electrocatalytic coupling-annulation of quinoxalin-2(1H)-ones with N-arylglycines was developed. A broad range of tetrahydroimidazo[1,5-a]quinoxalin-4(5H)-ones were obtaine...The first example of TBAI/H_(2)O cooperative electrocatalytic coupling-annulation of quinoxalin-2(1H)-ones with N-arylglycines was developed. A broad range of tetrahydroimidazo[1,5-a]quinoxalin-4(5H)-ones were obtained in good to excellent yields with exclusive chemoselectivities and excellent regioselectivities. The H-hydrogen bond served as a key factor for the electrocatalytic production of aminomethyl radical at lower oxidative potential.展开更多
In this study we report a new reaction pathway in which the hydroxyl and the aldehyde groups of 5-hydroxymethyl furfural were aminated respectively. Hydroxyl group was aminated via Ritter reaction followed by direct r...In this study we report a new reaction pathway in which the hydroxyl and the aldehyde groups of 5-hydroxymethyl furfural were aminated respectively. Hydroxyl group was aminated via Ritter reaction followed by direct reductive amination of aldehyde group. For the Ritter reaction of 5-hydroxymethyl furfural, mixture of trifluoromethane sulfonic acid and phosphoric anhydride showed good performance and the intermediate N-acyl-5-aminomethyl furfural with the highest yield of 89.1 wt% was obtained.Optimization of direct reductive amination of 2,5-bis（aminomethyl） furan was conducted and a yield of45.7 wt% was achieved. This study presents a simple way for preparing bis（amino）furans from renewable biomass based 5-hydroxymethyl furfural, which enriches the biorefinery concept from biomass.展开更多
A convenient approach for the preparation of （4R,5R）-4,5-bis（aminomethyl）-2-isopropyl-l,3-dioxolane is described. The target compound via two steps is synthesized from diethyl-2,3-O-isobutylidene-D-tartrate, throu...A convenient approach for the preparation of （4R,5R）-4,5-bis（aminomethyl）-2-isopropyl-l,3-dioxolane is described. The target compound via two steps is synthesized from diethyl-2,3-O-isobutylidene-D-tartrate, through ammonolysis and reduction.展开更多
The stability constants of binary complexes Ln-L (Ln = La3+, Ce3+, Pr3+, Nd3+, Sm3+, Eu3+, Gd3+ Tb3+, Dy3+, Ho3+, L = N, N'-bis (2'-pyridine) methyl-1, 10-phenanthroline-2, 9-dimethanamine) were determined by ...The stability constants of binary complexes Ln-L (Ln = La3+, Ce3+, Pr3+, Nd3+, Sm3+, Eu3+, Gd3+ Tb3+, Dy3+, Ho3+, L = N, N'-bis (2'-pyridine) methyl-1, 10-phenanthroline-2, 9-dimethanamine) were determined by pH potentiometric titration method at 25 +/- 0.1degreesC in 0.1 mol . L-1 NaClO4. The probable structures of the corresponding complexes were proposed. The influence of the metal ions to the stability of binary complexes and the stability difference between the complexes of rare earth ion and the corresponding complexes of Co2+, Ni2+, Cu2+ ions were discussed. The stability constants of the corresponding binary complex of radioactive Pm3+ ion were estimated by linear regression.展开更多
Urokinase-type plasminogen activator （uPA） is a trypsin-like serine protease and plays a key role in several biological processes, including tissue remodeling, cell migration, and matrix degradation. The inhibitors ...Urokinase-type plasminogen activator （uPA） is a trypsin-like serine protease and plays a key role in several biological processes, including tissue remodeling, cell migration, and matrix degradation. The inhibitors of uPA have been shown to prevent the spread of metastasis and tumor growth, and accordingly uPA is widely recognized as a target for the treatment of cancer. In this work, we report the crystal structures of the complexes of uPA with its inhibitors： 4- （aminomethyl）-benzoic acid （AMBA） and 4-（aminomethyl-phenyl）-methanol （AMPM）, both at a resolution of 2.35 А. The inhibitory constants of these two inhibitors were measured by a chromogenic competitive assay, and it was found that AMBA is a better inhibitor for uPA （Ki = 2.68 mM） than AMPM （Ki = 13.99 mM）. The structural study shows that the binding mode of inhibitor AMBA on uPA is similar to that of AMPM on uPA, both docked into the active site S1 pocket of uPA. Structural details of these complexes are provided to explain the difference of inhibitory constants.展开更多
We herein report the electrosynthesis of an aminomethyl functionalized poly（3,4-ethylenedioxythiophene）（PEDOT） derivative, poly（2＇-aminomethyl-3,4-ethylenedioxythiophene）（PEDOT-Me NH2）, in CH2Cl2-Bu4NPF6（0.1...We herein report the electrosynthesis of an aminomethyl functionalized poly（3,4-ethylenedioxythiophene）（PEDOT） derivative, poly（2＇-aminomethyl-3,4-ethylenedioxythiophene）（PEDOT-Me NH2）, in CH2Cl2-Bu4NPF6（0.1 mol·L^-1） system containing 2% boron trifluoride diethyl etherate（BFEE）. The electrochemical behavior, structure characterization, thermal properties and surface morphology of this novel polymer were systematically investigated by cyclic voltammetry（CV）, Fourier-transform infrared spectroscopy（FTIR）, thermogravimetry（TG） and scanning electron microscopy（SEM）, respectively. Electrochemistry results demonstrated that PEDOT-Me NH2 film displayed good redox properties and high electrochemical stability. Besides, PEDOT-Me NH2 films exhibited the electrochromic nature with obvious color changing from purple in the reduced form to blue upon oxidation. By further investigation, kinetic studies revealed that PEDOT-Me NH2 film had decent contrast ratio（41.8%）, favorable coloration efficiency（152.1 cm^2·C^-1）, low switching voltages and moderate response time（2.4 s）. Satisfactory results implied that the obtained PEDOT-Me NH2 film is a promising optoelectronic material and holds promise for electrochromic devices and display applications.展开更多
1 Introduction Immobilization of homogeneous catalysts onto polymer supports through covalent attachment has received wide attention because these materials offer advantage features of heterogeneous catalysis to homog...1 Introduction Immobilization of homogeneous catalysts onto polymer supports through covalent attachment has received wide attention because these materials offer advantage features of heterogeneous catalysis to homogeneous systems.The polymer-supported catalysts enhance their thermal stability,selectivity,recyclability and easy separation from reaction products leading to the operationally flexible[1-2].Such behaviour prompted us to know the effect of pore structures of polymer supporters on catalytic ...展开更多
b Institute of Oceanography and Environment, Xiamen University, Xiamen, Fujian 361005, China In this paper, a new ligand, 2,9 bis[ N,N bis(carboxymeth yl) aminomethyl] 1,10 phenanthroline, was synt...b Institute of Oceanography and Environment, Xiamen University, Xiamen, Fujian 361005, China In this paper, a new ligand, 2,9 bis[ N,N bis(carboxymeth yl) aminomethyl] 1,10 phenanthroline, was synthesized and used to establish a novel fluorimetric method for the determination of trace amounts of europium. The fluorescence intensity was a linear function of the concentration of europium in the range of 4.0×10 -9 -1.0×10 -6 mol/L. The detection limit was 1.0×10 -9 mol/L. The standard addition method was used to determine the europium in a synthetic rare earth sample and high purity Y 2O 3 matrix with satisfactory results.展开更多
基金This research was supported by the National Natural Science Foundation of China （Nos. 21672199 and 21790333） and CAS Interdisciplinary Innovation Team.
文摘A new palladium-catalyzed selective aminomethylation of conjugated 1,3-dienes with aminais via double C-N bond activation is described. This simple method provides an effective and rapid approach for the synthesis of linear a,13-unsaturated allylic amines with perfect regioselectivity. Mechanistic studies disclosed that one palladium catalyst cleaved two distinct C-N bond to furnish a cascade double C-N bond activation, in which an allylic 1,3-diamine and allylic 1,2-diamine were initially formed as key intermediates through the palladium-catalyzed C-N bond activation of aminal and the α,β-unsaturated allylic amine was subsequently produced via palladium-catalyzed C-N bond activation of the allylic diamines.
基金This work was supported by the Ministry of Education(MOE)of Singapore(no.R-143-000-A93-112).
文摘Chiral amines are synthetically versatile intermedi-ates used for the preparation of a wide range of biologically active compounds and drugs.Compared with the well-developed synthesis ofα-stereogenic amines,the establishment of enantioselective protocols to accessβ-stereogenic amines are very limited.
基金the National Natural Science Foundation of China(Nos.21672199,21790333,21925111 and 21702197)the Fundamental Research Funds for the Central Universities(No.WK2060190086).
文摘Main observation and conclusion A new strategy for the generation of the active Pd-alkyl species from aminal via C-N bond activation has been established,in which the formation of zwitterionic intermediate through aza-Michael addition of aminal to nitrodienes or dienones is identified as a key step for the activation of the C-N bond.The efficient strategy has enabled a new palladium-catalyzed a-aminomethylation of nitro-dienes and dienones via double C-N bond activation.The scope and versatility of the reaction were demonstrated and a broad range of substrates bearing electron-donating and-withdrawing groups on the aromatic rings were all compatible with this reaction to furnish the desired a-aminomethylated products in moderate to good yields with excellent regioselectivities and E/Z selectivities.
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This work was financially supported by the Natural Science Foundation of Tianjin (No. 013606111)
文摘The regioselective Mannich-type aminomethylation of hydroquinone afforded a nitrogen-containing compound, 2,5-bis-(morpholinomethyl)hydroquinone A, and its crystal structure was determined by single-crystal X-ray diffraction. Crystal data for A: C16H24N2O4, Mr = 308.37, orthorhombic, space group Pbca, a = 10.479(4), b = 10.298(4), c = 14.865(5) ?, V = 1604.3(11) ?3, Z = 4, Dc = 1.277 g/cm3, F(000) = 664, μ = 0.092 mm-1, GOF = 1.078, the final R = 0.0508 and wR = 0.1075 for 1416 observed reflections with I > 2σ(I). There exist two intramolecular O–H…N hy- drogen bonds between the phenolic O atoms and the morpholine N donors and the morpholino rings assume the preferred chair conformation.
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financial support from the University of South China。
文摘The first example of TBAI/H_(2)O cooperative electrocatalytic coupling-annulation of quinoxalin-2(1H)-ones with N-arylglycines was developed. A broad range of tetrahydroimidazo[1,5-a]quinoxalin-4(5H)-ones were obtained in good to excellent yields with exclusive chemoselectivities and excellent regioselectivities. The H-hydrogen bond served as a key factor for the electrocatalytic production of aminomethyl radical at lower oxidative potential.
基金the financial support from the National Natural Science Foundation of China(no.21676223 and no.21506177)the Fujian Provincial Development and Reform Commission,China(no.2015489)+1 种基金the Natural Science Foundation of Fujian Province of China(no.2016J01077 and no.2015J05034)the Fundamental Research Funds for the Central Universities of China(nos.20720160077 and 20720160087)
文摘In this study we report a new reaction pathway in which the hydroxyl and the aldehyde groups of 5-hydroxymethyl furfural were aminated respectively. Hydroxyl group was aminated via Ritter reaction followed by direct reductive amination of aldehyde group. For the Ritter reaction of 5-hydroxymethyl furfural, mixture of trifluoromethane sulfonic acid and phosphoric anhydride showed good performance and the intermediate N-acyl-5-aminomethyl furfural with the highest yield of 89.1 wt% was obtained.Optimization of direct reductive amination of 2,5-bis（aminomethyl） furan was conducted and a yield of45.7 wt% was achieved. This study presents a simple way for preparing bis（amino）furans from renewable biomass based 5-hydroxymethyl furfural, which enriches the biorefinery concept from biomass.
文摘A convenient approach for the preparation of （4R,5R）-4,5-bis（aminomethyl）-2-isopropyl-l,3-dioxolane is described. The target compound via two steps is synthesized from diethyl-2,3-O-isobutylidene-D-tartrate, through ammonolysis and reduction.
文摘The stability constants of binary complexes Ln-L (Ln = La3+, Ce3+, Pr3+, Nd3+, Sm3+, Eu3+, Gd3+ Tb3+, Dy3+, Ho3+, L = N, N'-bis (2'-pyridine) methyl-1, 10-phenanthroline-2, 9-dimethanamine) were determined by pH potentiometric titration method at 25 +/- 0.1degreesC in 0.1 mol . L-1 NaClO4. The probable structures of the corresponding complexes were proposed. The influence of the metal ions to the stability of binary complexes and the stability difference between the complexes of rare earth ion and the corresponding complexes of Co2+, Ni2+, Cu2+ ions were discussed. The stability constants of the corresponding binary complex of radioactive Pm3+ ion were estimated by linear regression.
基金Supported by the National Natural Science Foundation of China (30430190, 30625011)973 (2007CB914304)Young Talent Programme of Fujian Province (2007F3119)
文摘Urokinase-type plasminogen activator （uPA） is a trypsin-like serine protease and plays a key role in several biological processes, including tissue remodeling, cell migration, and matrix degradation. The inhibitors of uPA have been shown to prevent the spread of metastasis and tumor growth, and accordingly uPA is widely recognized as a target for the treatment of cancer. In this work, we report the crystal structures of the complexes of uPA with its inhibitors： 4- （aminomethyl）-benzoic acid （AMBA） and 4-（aminomethyl-phenyl）-methanol （AMPM）, both at a resolution of 2.35 А. The inhibitory constants of these two inhibitors were measured by a chromogenic competitive assay, and it was found that AMBA is a better inhibitor for uPA （Ki = 2.68 mM） than AMPM （Ki = 13.99 mM）. The structural study shows that the binding mode of inhibitor AMBA on uPA is similar to that of AMPM on uPA, both docked into the active site S1 pocket of uPA. Structural details of these complexes are provided to explain the difference of inhibitory constants.
基金financially supported by the National Natural Science Foundation of China(Nos.51263010,51303073,51272096 and 51403008)Natural Science Foundation of Jiangxi Province(Nos.20122BAB216011,20142BAB206028 and 2014BAB216029)the Science and Technology Landing Plan of Universities in Jiangxi province(No.KJLD14069)
文摘We herein report the electrosynthesis of an aminomethyl functionalized poly（3,4-ethylenedioxythiophene）（PEDOT） derivative, poly（2＇-aminomethyl-3,4-ethylenedioxythiophene）（PEDOT-Me NH2）, in CH2Cl2-Bu4NPF6（0.1 mol·L^-1） system containing 2% boron trifluoride diethyl etherate（BFEE）. The electrochemical behavior, structure characterization, thermal properties and surface morphology of this novel polymer were systematically investigated by cyclic voltammetry（CV）, Fourier-transform infrared spectroscopy（FTIR）, thermogravimetry（TG） and scanning electron microscopy（SEM）, respectively. Electrochemistry results demonstrated that PEDOT-Me NH2 film displayed good redox properties and high electrochemical stability. Besides, PEDOT-Me NH2 films exhibited the electrochromic nature with obvious color changing from purple in the reduced form to blue upon oxidation. By further investigation, kinetic studies revealed that PEDOT-Me NH2 film had decent contrast ratio（41.8%）, favorable coloration efficiency（152.1 cm^2·C^-1）, low switching voltages and moderate response time（2.4 s）. Satisfactory results implied that the obtained PEDOT-Me NH2 film is a promising optoelectronic material and holds promise for electrochromic devices and display applications.
文摘1 Introduction Immobilization of homogeneous catalysts onto polymer supports through covalent attachment has received wide attention because these materials offer advantage features of heterogeneous catalysis to homogeneous systems.The polymer-supported catalysts enhance their thermal stability,selectivity,recyclability and easy separation from reaction products leading to the operationally flexible[1-2].Such behaviour prompted us to know the effect of pore structures of polymer supporters on catalytic ...
基金theOcean 86 3ProjectFoundation (No .8190 70 4 )theNaturalScienceFoundation (No.D0 110 0 0 2 )ofFujianProvince China
文摘b Institute of Oceanography and Environment, Xiamen University, Xiamen, Fujian 361005, China In this paper, a new ligand, 2,9 bis[ N,N bis(carboxymeth yl) aminomethyl] 1,10 phenanthroline, was synthesized and used to establish a novel fluorimetric method for the determination of trace amounts of europium. The fluorescence intensity was a linear function of the concentration of europium in the range of 4.0×10 -9 -1.0×10 -6 mol/L. The detection limit was 1.0×10 -9 mol/L. The standard addition method was used to determine the europium in a synthetic rare earth sample and high purity Y 2O 3 matrix with satisfactory results.
