The aminolysis of ethyl acetate was promoted significantly via continuous reaction in a tubular reactor.Npropylacetamide was thus synthesized without presence of solvent and catalyst.The optimum conditions were obtain...The aminolysis of ethyl acetate was promoted significantly via continuous reaction in a tubular reactor.Npropylacetamide was thus synthesized without presence of solvent and catalyst.The optimum conditions were obtained as follows:the reaction temperature is 218℃,the reaction pressure is 3.5 MPa,the molar ratio(ethyl acetate:N-propylamine)is 1:1,and the residence time is 350 min.Accordingly,the conversion of ethyl acetate is up to94.8%.Furthermore,the kinetics of the rapid reaction stage(when the conversion of ethyl acetate is 20%-80%)can be expressed as Ink=-4629.441/T+2.1366,and the apparent activation energy is Ea=38489 J·mol-1.展开更多
Direct aminolysis of selenoester in aqueous media was investigated as a glycopeptide ligation strategy.This strategy allows the peptide and glycopeptide ligation to proceed smoothly(even with hindered amino acids) wit...Direct aminolysis of selenoester in aqueous media was investigated as a glycopeptide ligation strategy.This strategy allows the peptide and glycopeptide ligation to proceed smoothly(even with hindered amino acids) without the need of cysteine residue, N-terminal thiol auxiliary or coupling additive, and to afford the corresponding amide products in excellent yields. No epimerization was observed during ligation reations. In this work, the selenoester of unprotected glycopeptide was readily prepared, and the direct aminolysis of glycopeptide selenoester was successfully applied to synthesize MUC1 mucin sequence efficiently.展开更多
A comprehensive exploration of the aminolysis mechanism for methyl indole-3-acetate with ammonia is carried out by employing the B3 LYP/6-311++G(d,p), M06-2 X/6-311++G(d,p) and MP2/6-311++G(d,p)//M06-2 X/6-311++G(d,p)...A comprehensive exploration of the aminolysis mechanism for methyl indole-3-acetate with ammonia is carried out by employing the B3 LYP/6-311++G(d,p), M06-2 X/6-311++G(d,p) and MP2/6-311++G(d,p)//M06-2 X/6-311++G(d,p) levels. Two alterative reaction channels of the concerted and addition/elimination stepwise processes including the uncatalyzed, base-catalyzed reactions are taken into consideration. Subsequently, the substituent effects and solvent effects in methanol are also evaluated at the M06-2 X/6-311++G(d,p) level. The calculated results indicate that the calculated values of M06-2 X level are quite close to those of MP2, the stepwise pathway has more advantages to the concerted one for all of the reaction processes and the catalyst facilitates the proton migration and decreases the energy barriers as well. It is shown that the most preferred mechanism is the based-catalyzed stepwise process, the substituent of NH2 group slightly accelerates all the aminolysis reaction processes, and the solvent effect does not remarkably change the mechanism of the reaction.展开更多
Lewis acidic guanidinium ionic liquid（LAGIL） 2c was used as a novel, efficient and recyclable catalyst for aminolysis of epoxides under solvent-free and room temperature conditions, giving the corresponding β-amino...Lewis acidic guanidinium ionic liquid（LAGIL） 2c was used as a novel, efficient and recyclable catalyst for aminolysis of epoxides under solvent-free and room temperature conditions, giving the corresponding β-amino alcohols with moderate to excellent regioselectivity（up to 91：9） in high yields（up to 97%）. In addition, LAGIL 2c was recycled three times without any loss of catalytic activity and selectivity to the product.展开更多
This paper reports a computational study elucidating reaction mechanism for amide bond formation from esters and amines catalyzed by acetic acid. Two optional mechanisms（namely, classic stepwise and concerted acyl su...This paper reports a computational study elucidating reaction mechanism for amide bond formation from esters and amines catalyzed by acetic acid. Two optional mechanisms（namely, classic stepwise and concerted acyl substitution mechanisms） have been studied. Calculation results establish the reaction energy profiles of both mechanisms and locate all the intermediates and transition states in both catalytic cycles. Our results propose that the concerted acyl substitution mechanism may be more likely wherein the formation of CààN bond and the cleavage of CààO bond occur concurrently without the need of rehybridization of the carbonyl carbon. This is also consistent with the fact that no significant racemization/epimerization were observed in the amide products when asymmetric esters and/or amines were used as the reactants, because concerted acyl substitution mechanism precludes the intermediacy of tetrahedral adducts and the accompanying generation/elimination of new chiral centers.Further discussion implies that the concerted acyl substitution mechanism may widely occur in related amidation reactions in the presence of different types of coupling reagents.展开更多
The aminolysis can effectively introduce primary amine （- quent surface fiiofunctionalization reactions. However, less NH2） groups onto polyester materials, enabling a variety of subse- attention has been paid to th...The aminolysis can effectively introduce primary amine （- quent surface fiiofunctionalization reactions. However, less NH2） groups onto polyester materials, enabling a variety of subse- attention has been paid to the basic knowledge of aminolysis reac- tion in terms of reaction kinetics and its influences on materials properties. In this study, taking the widely used poly（e-caprolactone） （PCL） as a typical example, the influences of diamines and solvent property on the surface -NH2 density are firstly assessed by using X-ray photoelectron spectroscopy （XPS） and colorimetric analysis. Results show that smaller dia- mine molecules and nonpolar alcohols could accelerate the reaction. The reaction kinetics with 1,6-hexanediamine is further investigated as a function of temperature, reaction time, and diamine concentration. During the initial stage, the reaction shows a 1^st order kinetics with the diamine concentration and has an activation energy of 54.5 kJ/mol. Ionization state of the -NH2 groups on the PCL surface is determined, revealing that the pKa of -NH3^＋ （〈5） is much lower than that of the corresponding diamine molecules in solution. After aminolysis, surface hydrophilicity of PCL membrane is significantly enhanced, while surface elastic modulus and average molecular weight are decreased to some extent, and others such as weight, surface mor- phology and bulk mechanical strength are not apparently changed. The introduced -NH2 groups are found to be largely lost at 37 ℃, but can be mostly maintained at low temperature.展开更多
Surface hydrophilization is required for numbers of applications such as biosensor,biomedical implants and marine coating.However,the preparation of hydrophilic surface from a solid substrate still suffers from limite...Surface hydrophilization is required for numbers of applications such as biosensor,biomedical implants and marine coating.However,the preparation of hydrophilic surface from a solid substrate still suffers from limited thicknesses,complex procedures,restricted substrates and harsh conditions.Herein,a method based on in-situ aminolysis of poly(pentafluorophenyl acrylate)(pPFPA)capable of generating arbitrary hydrophilic surface is proposed,enabling high design freedom and abundant choices of hydrophilic molecules.Simply immersing pPFPA coated substrates into 3-((3-aminopropyl)dimethylammonio)propane-1-sulfonate(ADPS),β-alanine and amine-terminal poly(ethylene glycol)(NH2-PEG)solutions for two hours drastically reduces the water contact angle of the corresponding surfaces,indicating the high efficiency and excellent generality of such method.Systematical studies reveal that these coatings are able to mitigate fog formation,self-clean the oil contaminant and exhibit excellent antifouling performance against algae.Notably,relying on the fast and quantitative feature of the aminolysis,these hydrophilic surfaces possess excellent regeneration capability and well-recover their hydrophilic feature after being physically damaged.This work represents a facile and universal way to fabricate versatile hydrophilic surfaces for multi-functional applications such as self-cleaning,patterning,sensing,antifogging and anti-biofouling.展开更多
The aminolysis and the effect of water on the aminolysis processes of n-methyl β-sultam have been studied using density functional theory （DFF） method at the B3LYP/6-31G＊ level. The stationary structures and energ...The aminolysis and the effect of water on the aminolysis processes of n-methyl β-sultam have been studied using density functional theory （DFF） method at the B3LYP/6-31G＊ level. The stationary structures and energies have been investigated for both reactions to find two different reaction channels. Specific and general solvent effects have been evaluated and the most favored pathway was found. The presence of solvent disfavors the reaction, whereas the participation of water in the aminolysis reaction plays a positive role and reduces the activation energy greatly. All transition states in the assisted aminolysis are 35-70 kJ/mol lower than those for the non-assisted reaction.展开更多
We first make use of aminolysis of calix[4]arene esters to synthesize calix[4]arene amides. When the two ethyl esters of the calix[4]arene esters are aminolysized, the 1, 3-amide derivative is formed selectively. The ...We first make use of aminolysis of calix[4]arene esters to synthesize calix[4]arene amides. When the two ethyl esters of the calix[4]arene esters are aminolysized, the 1, 3-amide derivative is formed selectively. The crystal structures of the calix-[4] arene with two butyl amide (3b) and four butyl amide moieties (4b) were determined. The intermolecular hydrogen bonds make 4b form two-dimensional net work insolid state. The 1H NMR spectra prove mat 3b is of a pinched cone conformation, while 4b and tetraheptylamide-calix[4]arene (6b) take fast interconversion between two C2r isomers in solution and appear an apparent cone conformation at room temperature. As decreasing temperature, the interconversion rate decreases gradually and, finally, the interconversion process is frozen at Tc = ?10°C, which makes both conformations of 4b and 6b the pinched cone structures. The hydrogen bond improves the interconversion barrier, and the large different values of the potential barrier between 6b and 4b (or 6b) may be of forming different hydrogen bonds.展开更多
Three new functional group containing borazine derivatives, 2,4,6-tri（allylamino）borazine, 2,4,6-tri（3-ethynylanilino）borazine, and 2,4,6-tri（4-propargyl oxyanilino）borazine were synthesized by aminolysis reacti...Three new functional group containing borazine derivatives, 2,4,6-tri（allylamino）borazine, 2,4,6-tri（3-ethynylanilino）borazine, and 2,4,6-tri（4-propargyl oxyanilino）borazine were synthesized by aminolysis reaction of 2,4,6-trichloroborazine ClaB3N3H3（TCB）. The new compounds were characterized by infrared （IR） spectra, nuclear magnetic resonance （NMR）, and mass spectrometry （MS）.展开更多
The derivatives of 4-alkyl-2-quinolones possess a variety of biological activities. The general synthetic method of 4-alkyl-2-quinolones is the reaction of aryl amines with β-ketoesters to form β-ketoamides, which a...The derivatives of 4-alkyl-2-quinolones possess a variety of biological activities. The general synthetic method of 4-alkyl-2-quinolones is the reaction of aryl amines with β-ketoesters to form β-ketoamides, which are then heated in concentrated sulfuric acid to complete the ring closure. Although a number of its 4-methyl and aryl derivatives have been obtained, other 4-alkyl-2-quinolones are rarely mentioned for lack of a convenient method to prepare the appropriate β-ketoesters used in condensation.展开更多
Some 1-imino-3,3-disubstituted-1,3-dihydro isobenzofuran and 2-(1,1-disubstituted hydroxymethyl) benzamide derivatives have been obtained by the aminolysis of phthalide in the presence of triethylamine/aluminum chlori...Some 1-imino-3,3-disubstituted-1,3-dihydro isobenzofuran and 2-(1,1-disubstituted hydroxymethyl) benzamide derivatives have been obtained by the aminolysis of phthalide in the presence of triethylamine/aluminum chloride. 1-Benzylimino-3,3-disubstituted-1,3-dihydro isobenzofuran can be peroxidized to the corresponding hydroperoxides on exposure to the air for a long period. The structure was characterized by single crystal X-ray diffraction and the possible mechanism was suggested.展开更多
A one-pot reaction sequence of sequential phosphine-promoted tandem annulations of aryl trifluoromethyl ketones and MBH（Morita-Baylis-Hillman） carbonates and DBU-mediated aminolysis was developed. This method provid...A one-pot reaction sequence of sequential phosphine-promoted tandem annulations of aryl trifluoromethyl ketones and MBH（Morita-Baylis-Hillman） carbonates and DBU-mediated aminolysis was developed. This method provides a step-economical approach to trifluoromethylated dienamides with diverse structural complexity from readily available starting materials in moderate yields.展开更多
We develop here a simple wet chemistry to prepare covalent functionalized graphenes （FGs） through epoxide aminolysis espe- cially under alkaline aqueous condition. Remarkably, a series of typical monoamines, such as...We develop here a simple wet chemistry to prepare covalent functionalized graphenes （FGs） through epoxide aminolysis espe- cially under alkaline aqueous condition. Remarkably, a series of typical monoamines, such as industrial Huntsman Jeffamine M-2070 and M-2005 polymer with hydrophilic or hydrophobic polyetheramine chains, positively-charged 2-amino-N,N,N- trimethylpropanaminium, negatively-charged sulfanilic acid, even oligopeptide sequence, can be effectively grafted on the platelets of graphene oxide precursor with covalent functionalization and partially reduced features. This strategy provides the researchers a facile and convenient approach to design and synthesize solution processable, biocompatible and functionalized graphenes for the potent applications in electronic inks, drug carriers and biomedicines. Expansion of the current study is actively ongoing in our laboratory.展开更多
A six-step synthesis of （-）-clausenamide is described. Optically pure （R,E）-1,3-diphenylallylic alcohol was ac-etylated and then subjected to an Ireland-Claisen rearrangement, giving the γ,δ-unsaturated acid, wh...A six-step synthesis of （-）-clausenamide is described. Optically pure （R,E）-1,3-diphenylallylic alcohol was ac-etylated and then subjected to an Ireland-Claisen rearrangement, giving the γ,δ-unsaturated acid, which underwent a substrate-induced stereoselective bromolactonization to afford the expected all-equatorial substituted bromo-δ-lac-one. An unusual chemo-selective aminolysis of the lactone resulted in the formation of a γ,δ-epoxy-amide in stereospecific manner. Base-promoted cyclization of this intermediate and the subsequent Davis oxidation furnished the synthesis, delivering the final product in 〉99% ee and up to 34% overall yield.展开更多
基金financial support from the National Natural Science Foundation of China(21476194)the National Key Research and Development Program of China(2016YFB0301800).
文摘The aminolysis of ethyl acetate was promoted significantly via continuous reaction in a tubular reactor.Npropylacetamide was thus synthesized without presence of solvent and catalyst.The optimum conditions were obtained as follows:the reaction temperature is 218℃,the reaction pressure is 3.5 MPa,the molar ratio(ethyl acetate:N-propylamine)is 1:1,and the residence time is 350 min.Accordingly,the conversion of ethyl acetate is up to94.8%.Furthermore,the kinetics of the rapid reaction stage(when the conversion of ethyl acetate is 20%-80%)can be expressed as Ink=-4629.441/T+2.1366,and the apparent activation energy is Ea=38489 J·mol-1.
基金supported by the National Key Research and Development Program of China (No. 2017YFA0505200)the National Natural Science Foundation of China (No. 21772056)+2 种基金Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation Open Foundation (No. JXMS201701)the self-determined research funds of CCNU from the colleges' basic research and operation of MOE (No. CCNU18TS011)the Program of Introducing Talents of Discipline to Universities of China(111 program, No. B17019)
文摘Direct aminolysis of selenoester in aqueous media was investigated as a glycopeptide ligation strategy.This strategy allows the peptide and glycopeptide ligation to proceed smoothly(even with hindered amino acids) without the need of cysteine residue, N-terminal thiol auxiliary or coupling additive, and to afford the corresponding amide products in excellent yields. No epimerization was observed during ligation reations. In this work, the selenoester of unprotected glycopeptide was readily prepared, and the direct aminolysis of glycopeptide selenoester was successfully applied to synthesize MUC1 mucin sequence efficiently.
基金supported by the Special Funds of the National Natural Science Foundation of China(No.11347161)
文摘A comprehensive exploration of the aminolysis mechanism for methyl indole-3-acetate with ammonia is carried out by employing the B3 LYP/6-311++G(d,p), M06-2 X/6-311++G(d,p) and MP2/6-311++G(d,p)//M06-2 X/6-311++G(d,p) levels. Two alterative reaction channels of the concerted and addition/elimination stepwise processes including the uncatalyzed, base-catalyzed reactions are taken into consideration. Subsequently, the substituent effects and solvent effects in methanol are also evaluated at the M06-2 X/6-311++G(d,p) level. The calculated results indicate that the calculated values of M06-2 X level are quite close to those of MP2, the stepwise pathway has more advantages to the concerted one for all of the reaction processes and the catalyst facilitates the proton migration and decreases the energy barriers as well. It is shown that the most preferred mechanism is the based-catalyzed stepwise process, the substituent of NH2 group slightly accelerates all the aminolysis reaction processes, and the solvent effect does not remarkably change the mechanism of the reaction.
文摘Lewis acidic guanidinium ionic liquid（LAGIL） 2c was used as a novel, efficient and recyclable catalyst for aminolysis of epoxides under solvent-free and room temperature conditions, giving the corresponding β-amino alcohols with moderate to excellent regioselectivity（up to 91：9） in high yields（up to 97%）. In addition, LAGIL 2c was recycled three times without any loss of catalytic activity and selectivity to the product.
基金supported by the National Natural Science Foundation of China (No. 21472068)Financial support from MOE & SAFEA for the 111 Project (No. B13025)is also gratefully acknowledged
文摘This paper reports a computational study elucidating reaction mechanism for amide bond formation from esters and amines catalyzed by acetic acid. Two optional mechanisms（namely, classic stepwise and concerted acyl substitution mechanisms） have been studied. Calculation results establish the reaction energy profiles of both mechanisms and locate all the intermediates and transition states in both catalytic cycles. Our results propose that the concerted acyl substitution mechanism may be more likely wherein the formation of CààN bond and the cleavage of CààO bond occur concurrently without the need of rehybridization of the carbonyl carbon. This is also consistent with the fact that no significant racemization/epimerization were observed in the amide products when asymmetric esters and/or amines were used as the reactants, because concerted acyl substitution mechanism precludes the intermediacy of tetrahedral adducts and the accompanying generation/elimination of new chiral centers.Further discussion implies that the concerted acyl substitution mechanism may widely occur in related amidation reactions in the presence of different types of coupling reagents.
基金financially supported by the National Natural Science Foundation of China (20934003)the National Basic Research Program of China (2011CB606203)
文摘The aminolysis can effectively introduce primary amine （- quent surface fiiofunctionalization reactions. However, less NH2） groups onto polyester materials, enabling a variety of subse- attention has been paid to the basic knowledge of aminolysis reac- tion in terms of reaction kinetics and its influences on materials properties. In this study, taking the widely used poly（e-caprolactone） （PCL） as a typical example, the influences of diamines and solvent property on the surface -NH2 density are firstly assessed by using X-ray photoelectron spectroscopy （XPS） and colorimetric analysis. Results show that smaller dia- mine molecules and nonpolar alcohols could accelerate the reaction. The reaction kinetics with 1,6-hexanediamine is further investigated as a function of temperature, reaction time, and diamine concentration. During the initial stage, the reaction shows a 1^st order kinetics with the diamine concentration and has an activation energy of 54.5 kJ/mol. Ionization state of the -NH2 groups on the PCL surface is determined, revealing that the pKa of -NH3^＋ （〈5） is much lower than that of the corresponding diamine molecules in solution. After aminolysis, surface hydrophilicity of PCL membrane is significantly enhanced, while surface elastic modulus and average molecular weight are decreased to some extent, and others such as weight, surface mor- phology and bulk mechanical strength are not apparently changed. The introduced -NH2 groups are found to be largely lost at 37 ℃, but can be mostly maintained at low temperature.
基金supported by the funding(E055AJ0101)from FJIRSM-CASNational Natural Science foundation of China(51803214)。
文摘Surface hydrophilization is required for numbers of applications such as biosensor,biomedical implants and marine coating.However,the preparation of hydrophilic surface from a solid substrate still suffers from limited thicknesses,complex procedures,restricted substrates and harsh conditions.Herein,a method based on in-situ aminolysis of poly(pentafluorophenyl acrylate)(pPFPA)capable of generating arbitrary hydrophilic surface is proposed,enabling high design freedom and abundant choices of hydrophilic molecules.Simply immersing pPFPA coated substrates into 3-((3-aminopropyl)dimethylammonio)propane-1-sulfonate(ADPS),β-alanine and amine-terminal poly(ethylene glycol)(NH2-PEG)solutions for two hours drastically reduces the water contact angle of the corresponding surfaces,indicating the high efficiency and excellent generality of such method.Systematical studies reveal that these coatings are able to mitigate fog formation,self-clean the oil contaminant and exhibit excellent antifouling performance against algae.Notably,relying on the fast and quantitative feature of the aminolysis,these hydrophilic surfaces possess excellent regeneration capability and well-recover their hydrophilic feature after being physically damaged.This work represents a facile and universal way to fabricate versatile hydrophilic surfaces for multi-functional applications such as self-cleaning,patterning,sensing,antifogging and anti-biofouling.
基金Project supported by the National Natural Science Foundation of China （Nos. 20373034, 20173032）, and Ph.D. Special Research Foundation of The Ministry of Education of China.
文摘The aminolysis and the effect of water on the aminolysis processes of n-methyl β-sultam have been studied using density functional theory （DFF） method at the B3LYP/6-31G＊ level. The stationary structures and energies have been investigated for both reactions to find two different reaction channels. Specific and general solvent effects have been evaluated and the most favored pathway was found. The presence of solvent disfavors the reaction, whereas the participation of water in the aminolysis reaction plays a positive role and reduces the activation energy greatly. All transition states in the assisted aminolysis are 35-70 kJ/mol lower than those for the non-assisted reaction.
基金Project supported by the National Natural Science Foundation of China.
文摘We first make use of aminolysis of calix[4]arene esters to synthesize calix[4]arene amides. When the two ethyl esters of the calix[4]arene esters are aminolysized, the 1, 3-amide derivative is formed selectively. The crystal structures of the calix-[4] arene with two butyl amide (3b) and four butyl amide moieties (4b) were determined. The intermolecular hydrogen bonds make 4b form two-dimensional net work insolid state. The 1H NMR spectra prove mat 3b is of a pinched cone conformation, while 4b and tetraheptylamide-calix[4]arene (6b) take fast interconversion between two C2r isomers in solution and appear an apparent cone conformation at room temperature. As decreasing temperature, the interconversion rate decreases gradually and, finally, the interconversion process is frozen at Tc = ?10°C, which makes both conformations of 4b and 6b the pinched cone structures. The hydrogen bond improves the interconversion barrier, and the large different values of the potential barrier between 6b and 4b (or 6b) may be of forming different hydrogen bonds.
文摘Three new functional group containing borazine derivatives, 2,4,6-tri（allylamino）borazine, 2,4,6-tri（3-ethynylanilino）borazine, and 2,4,6-tri（4-propargyl oxyanilino）borazine were synthesized by aminolysis reaction of 2,4,6-trichloroborazine ClaB3N3H3（TCB）. The new compounds were characterized by infrared （IR） spectra, nuclear magnetic resonance （NMR）, and mass spectrometry （MS）.
基金Supported by the National Natural Science Foundation of China
文摘The derivatives of 4-alkyl-2-quinolones possess a variety of biological activities. The general synthetic method of 4-alkyl-2-quinolones is the reaction of aryl amines with β-ketoesters to form β-ketoamides, which are then heated in concentrated sulfuric acid to complete the ring closure. Although a number of its 4-methyl and aryl derivatives have been obtained, other 4-alkyl-2-quinolones are rarely mentioned for lack of a convenient method to prepare the appropriate β-ketoesters used in condensation.
基金the Postdoctoral Foundation of China for the tlnancial support.
文摘Some 1-imino-3,3-disubstituted-1,3-dihydro isobenzofuran and 2-(1,1-disubstituted hydroxymethyl) benzamide derivatives have been obtained by the aminolysis of phthalide in the presence of triethylamine/aluminum chloride. 1-Benzylimino-3,3-disubstituted-1,3-dihydro isobenzofuran can be peroxidized to the corresponding hydroperoxides on exposure to the air for a long period. The structure was characterized by single crystal X-ray diffraction and the possible mechanism was suggested.
基金supported by the National Natural Science Foundation of China (No. 21302034)the Fundamental Research Funds for the Central Universities (No. 2013HGQC0028)
文摘A one-pot reaction sequence of sequential phosphine-promoted tandem annulations of aryl trifluoromethyl ketones and MBH（Morita-Baylis-Hillman） carbonates and DBU-mediated aminolysis was developed. This method provides a step-economical approach to trifluoromethylated dienamides with diverse structural complexity from readily available starting materials in moderate yields.
基金supported by the Ministry of Science and Technology of China (2014CB239402, 2013CB834505, 2013CB834804)the National Natural Science Foundation of China (91427303, 21372232, 21204052)+1 种基金the Key Research Programme of the Chinese Academy of Sciences (KGZD-EW-T05)the Foundation of Director of TIPC
文摘We develop here a simple wet chemistry to prepare covalent functionalized graphenes （FGs） through epoxide aminolysis espe- cially under alkaline aqueous condition. Remarkably, a series of typical monoamines, such as industrial Huntsman Jeffamine M-2070 and M-2005 polymer with hydrophilic or hydrophobic polyetheramine chains, positively-charged 2-amino-N,N,N- trimethylpropanaminium, negatively-charged sulfanilic acid, even oligopeptide sequence, can be effectively grafted on the platelets of graphene oxide precursor with covalent functionalization and partially reduced features. This strategy provides the researchers a facile and convenient approach to design and synthesize solution processable, biocompatible and functionalized graphenes for the potent applications in electronic inks, drug carriers and biomedicines. Expansion of the current study is actively ongoing in our laboratory.
文摘A six-step synthesis of （-）-clausenamide is described. Optically pure （R,E）-1,3-diphenylallylic alcohol was ac-etylated and then subjected to an Ireland-Claisen rearrangement, giving the γ,δ-unsaturated acid, which underwent a substrate-induced stereoselective bromolactonization to afford the expected all-equatorial substituted bromo-δ-lac-one. An unusual chemo-selective aminolysis of the lactone resulted in the formation of a γ,δ-epoxy-amide in stereospecific manner. Base-promoted cyclization of this intermediate and the subsequent Davis oxidation furnished the synthesis, delivering the final product in 〉99% ee and up to 34% overall yield.
