In order to resolve the increasing resistance phenomena of the Gram-negative bacteria against single chain quaternary ammonium salts (QAS), lysine with a pedant fluorinated bis-ammonium salts was synthesized and its...In order to resolve the increasing resistance phenomena of the Gram-negative bacteria against single chain quaternary ammonium salts (QAS), lysine with a pedant fluorinated bis-ammonium salts was synthesized and its antimicrobial properties were evaluated in this work. The novel fluorinated bis-ammonium salts shows similar activity with conventional single chain quaternary ammonium salts against Gram-positive bacteria but stronger activity against Gram-negative bacteria and yeast compared with the single chained counterpart.展开更多
The synergistic extraction of Cd(Ⅱ)with primary amine N-1923 and neutral organophosphorus reagents(TBP,DBBP,B)from hydrochloric acid has been investigated at μ=0.5,t=25℃.The compositions of the synergistic extracti...The synergistic extraction of Cd(Ⅱ)with primary amine N-1923 and neutral organophosphorus reagents(TBP,DBBP,B)from hydrochloric acid has been investigated at μ=0.5,t=25℃.The compositions of the synergistic extraction complexes and the mechanism of the synergistic extraction have been determined by the methods of slope and constant mole. The synergistic extraction complexes with composition(RNH_3Cl)_2·CdCl_2·B have been demonstrated.The synergistic extraction reactions and additional reaction of Cd(Ⅱ)have been proposed as follows: CdCl_2+2RNH_3Cl_(o)+B_(o)(RNH_3Cl)_2·CdCl_2·B_(o) (RNH_3Cl)_3·CdCl_(2(o)+B_(o)(RNH_3Cl)_2·CdCl_2·B_(o)+RNH_3Cl_(o) In addition,the equilibrium constants and the thermodynamic functions of the synergistic ex- traction reactions have been calculated.The IR and NMR spectra of the synergistic ext-ac- tion complexes of Cd(Ⅱ)have been studied as well.展开更多
Mechanism of extraction of Fe (III) from sulphate solution by primary amine N1923 and stripping of Fe loaded organic phase with dilute H_2SO_4 was investigated. The organic phase was characterized by FT-IR and photon ...Mechanism of extraction of Fe (III) from sulphate solution by primary amine N1923 and stripping of Fe loaded organic phase with dilute H_2SO_4 was investigated. The organic phase was characterized by FT-IR and photon correlation spectroscopy. The composition of extracted species as well as the content of H_2O in organic phase were determined. The dependence of both the rate of extraction and stripping on the formation of reverse micelle in primary amine (N1923)system has been confirmed. It is shown that the extraction of Fe(III) by primary amine sulphate may be related to the adduct formation or cation exchange reaction under different concentrations of H_2SO_4 in aqueous solution.展开更多
Direct alkylation with skipped enynes or cyclopropropylacetylenes represents an ideal process for the installation of pentadienyl group in terms of atom- and step-economy.The development of catalytic asymmetric versio...Direct alkylation with skipped enynes or cyclopropropylacetylenes represents an ideal process for the installation of pentadienyl group in terms of atom- and step-economy.The development of catalytic asymmetric versions has been frequently pursued and most of the successes have been achieved with enolizable aldehydes.We herein describe a synergistic chiral primary amine/Pd catalysis for asymmetric α-pentadienylation of β-ketocarbonyls and aldehydes with skipped enynes or cyclopropropylacetylenes.The reaction features the construction of acyclic all-carbon quaternary centers with high enantioselectivity,and good functional group tolerance and scalability.展开更多
Specific bioconjugation for native primary amines is highly valuable for both chemistry and biomedical research.Despite all the efforts,scientists lack a proper strategy to achieve high selectivity for primary amines,...Specific bioconjugation for native primary amines is highly valuable for both chemistry and biomedical research.Despite all the efforts,scientists lack a proper strategy to achieve high selectivity for primary amines,not to mention the requirement of fast response in real applications.Herein,we report a chromone-based aggregation-induced emission(AIE)fluorogen called CMVMN as a self-reporting bioconjugation reagent for selective primary amine identification,and its applications for monitoring bioprocesses of amination and protein labeling.CMVMN is AIE-active and capable of solid-state sensing.Thus,its electrospun films are manufactured for visualization of amine diffusion and leakage process.CMVMN also shows good biocompatibility and potential mitochondria-staining ability,which provides new insight for organelle-staining probe design.Combined with its facile synthesis and good reversibility,CMVMN would not only show wide potential applications in biology,but also offer new possibilities for molecular engineering.展开更多
It has been found that the two-phase reactions of aqueous HCl, HOAc or H_3PO_4 with primary amine N_ 1923 in chloroform are oscillating reactions. Their power-time curves were measured by the titration microcalorimet...It has been found that the two-phase reactions of aqueous HCl, HOAc or H_3PO_4 with primary amine N_ 1923 in chloroform are oscillating reactions. Their power-time curves were measured by the titration microcalorimetric method, and the induction period (t_ in). The first oscillating period (t_ p.1) and the second oscillating period (t_ p.2) were determined. The apparent activating parameters and the orders of the oscillating systems were calculated and the following relationships were established: for the oscillating system of hydrochloric acid t_ in∝c 0.147_ HClexp(1.35×10 3T), t_ p.1∝c 0.241_ HCl· exp(4.33×10 3T), t_ p.2∝c 0.290_ HClexp(5.59×10 3T); for the oscillating system of acetic acid, t_ in∝c 0.883_ HOAcexp(2.32×10 3T), t_ p.1∝c 0.399_ HOAc· exp(4.50×10 3T), t_ p.2∝c 0.301_ HOAcexp(5.88×10 3T); for the oscillating system of phosphoric acid, t_ in∝c 1.14_ H_3PO_4exp(7.70×10 4T), t_ p.1∝c 1.42_ H_3PO_4exp(1.14×10 4T), t_ p.2∝c 1.47_ H_3PO_4exp(1.27×10 4T).展开更多
A novel, convenient and efficient approach to the synthesis of pyrrole and imidazole derivatives via the reaction between primary amines, alkyl propiolates or isothiocyanate and oxalyl chloride is described. The metho...A novel, convenient and efficient approach to the synthesis of pyrrole and imidazole derivatives via the reaction between primary amines, alkyl propiolates or isothiocyanate and oxalyl chloride is described. The method offers several advantages including high yields of products and performing reaction under solvent-free conditions.展开更多
A microwave enhanced, solventless Mannich condensation of terminal alkynes, primary amines with paraformaldehyde on cuprous iodide doped alumina has been investigated. The structures of products depend on the ratio o...A microwave enhanced, solventless Mannich condensation of terminal alkynes, primary amines with paraformaldehyde on cuprous iodide doped alumina has been investigated. The structures of products depend on the ratio of alkyne to amine and paraformaldehyde.展开更多
An intramolecular organocatalytic enantioselective aza-Michael reaction of carbamates, sulfonamides and acetamides to a,b-unsaturated ketones was developed. This process is promoted by 9-amino-9-deoxy-epi-quinine and ...An intramolecular organocatalytic enantioselective aza-Michael reaction of carbamates, sulfonamides and acetamides to a,b-unsaturated ketones was developed. This process is promoted by 9-amino-9-deoxy-epi-quinine and diphenyl hydrogen phosphate to afford a straightforward and expeditious synthesis of several synthetically useful five-and six-membered heterocycles with excellent enantioselectivity(92%–97.5% ee) and very good yields(up to 99%).展开更多
We report herein the first example of asymmetric hydroazidation of α-substituted vinyl ketones by using chiral primary amines as the catalysts.A simple chiral primary-tertiary diamine catalyst derived from lphenylala...We report herein the first example of asymmetric hydroazidation of α-substituted vinyl ketones by using chiral primary amines as the catalysts.A simple chiral primary-tertiary diamine catalyst derived from lphenylalanine was found to readily promote this aza-Michael addition reaction with enamine protonation as the key stereogenic step,thus enabling the effective synthesis of α-chiral β-azido ketones with good yields and moderate enantioselectivities.展开更多
A primary amine functionalized ordered mesoporous phenolic resin(NH2-MPR)was obtained by an evaporationinduced self-assembly method.The as-prepared NH2-MPR material possessed large surface area and ordered twodimensio...A primary amine functionalized ordered mesoporous phenolic resin(NH2-MPR)was obtained by an evaporationinduced self-assembly method.The as-prepared NH2-MPR material possessed large surface area and ordered twodimensional hexagonal mesoporous structure.Also,the amine groups were well-dispersed in the mesoporous channels.It can act as an efficient solid base to promote Knoevenagel condensation of various aldehydes with ethyl cyanoacetate in water with high conversion and selectivity.This excellent performance was attributed ordered mesopores and hydrophobic pore surface,which resulted in the decreased the interference of water solvent and the increased active sites accessibility.Noted that it was comparable with homogenous base catalysts in the water-medium Knoevenagel condensation reaction,and it can be reused for at least five times without significant reduction in the catalytic efficiency.展开更多
The oxidative coupling of primary aromatic amines was investigated. Ce(SO4)2 can mediate the oxidative coupling of primary aromatic amines in water to dimers, trimers and/or tetramers, which depended on the substitu...The oxidative coupling of primary aromatic amines was investigated. Ce(SO4)2 can mediate the oxidative coupling of primary aromatic amines in water to dimers, trimers and/or tetramers, which depended on the substituents of primary aromatic amines. When 2,6-dimethylaniline or 2,6-diethylaniline was used as substrate, dimer, and tetramer were formed as major products. When 2,6-diisopropylaniline or 2,6-dihaloanilines was used as substrate, dimer, and trimer were formed. The mechanistic aspect was also investigated.展开更多
Sterically congestedα-tertiary primary amines are ubiquitous substructures in pharmaceutical and agrochemical agents yet are challenging to access.Herein,straightforward photoredox-catalyzed access to structurally di...Sterically congestedα-tertiary primary amines are ubiquitous substructures in pharmaceutical and agrochemical agents yet are challenging to access.Herein,straightforward photoredox-catalyzed access to structurally diverseα,α,α-trisubstituted primary amines from denitrogenative alkylarylation or dialkylation of vinyl azides with N-hydroxyphthalimide(NHPI)esters and cyanoarenes or aryl aldehydes has been developed.The use of vinyl azide as a precursor to a primary aminewas enabled by the dual role of the Hantzsch ester to form an electron donor-acceptor complex and serve as a sacrificial reductant.This strategy provides a modular synthesis ofα-tertiary primary amines,including unprotected 1,2-amino alcohols,from simple materials with excellent functional group tolerance.The synthetic applicability of this method was demonstrated by streamlined access to 2,2-disubstituted tetrahydroquinolines.Preliminary investigations support two parallel reductive photocatalytic cycles allowing for the denitrogenative alkylarylation or dialkylation of vinyl azides via decarboxylative radical addition followed by heteroradical cross-coupling betweenα-amino radicals and aryl anion radicals or ketyl anion radicals.展开更多
Wormlike/lamellar microporous carbons were prepared by using long alkyl chain primary amine hydrochloride as the template and resorci- nol/formaldehyde as the carbon source under highly acidic conditions. The template...Wormlike/lamellar microporous carbons were prepared by using long alkyl chain primary amine hydrochloride as the template and resorci- nol/formaldehyde as the carbon source under highly acidic conditions. The template can be eliminated by high temperature treatment under an inert atmosphere. The obtained carbon materials were characterized by N2 adsorption-desorption, transmission electron microscopy, ther- mogravimetry and scanning electron microscopy. The results show that dodecylamine hydrochloride surfactant can be used as the template of wormlike micropores structure while octadecylamine hydrochloride results in both lamellar and wormlike micropores. The obtained carbon materials have the similar pore size in the range of 0.5-0.59 nm, but with various morphologies such as monolith, spheres, and coralline. The microporous carbon obtained from dodecylamine hydrochloride surfactant shows good adsorption performance to remove the refractory sulfur compounds and nitrogen-containing compounds in fuel.展开更多
An unexpected reaction of 10-bromomethyl-12-oxocalanolide A(2) with primary amine was demonstrated and studied. Consequentially,a new method for the preparation of N-substituted pyrroles starting fromγ-halo-α,β-u...An unexpected reaction of 10-bromomethyl-12-oxocalanolide A(2) with primary amine was demonstrated and studied. Consequentially,a new method for the preparation of N-substituted pyrroles starting fromγ-halo-α,β-unsaturated ketone was presented.展开更多
Direct C(sp3)-H functionalization of N-unprotected aliphatic amines represents one of the most efficient and straightforward strategies for amine synthesis.Despite some recent progress in this field,the NH2-directed y...Direct C(sp3)-H functionalization of N-unprotected aliphatic amines represents one of the most efficient and straightforward strategies for amine synthesis.Despite some recent progress in this field,the NH2-directed y-C(sp3)-H arylation of primary aliphatic amines exceptα-amino esters remained an unmet challenge.In this report,we established a simple and efficient method for site-selective C(sp3)-H arylation of primary aliphatic amines by aryl iodides.In the presence of only 5 mol%Pd(OAc)2,a wide range of aliphatic amines including O-benzyl and O-silyl amino alcohols were arylated at y-orδ-positions by aryl iodides containing a broad scope of functional groups.The synthetic application of this method had also been demonstrated by large-scale synthesis,the synthesis of a fingolimod analogue,and the conjugation with natural D-menthol and fluorescent 1,8-naphthalimide.展开更多
The formation of toxic nitrogenous disinfection byproducts (N-DBPs), such as nitrosamines, halonitromethanes and haloacetonitriles, from reactions between chlorine/chloramine and dissolved organic nitrogen in drinki...The formation of toxic nitrogenous disinfection byproducts (N-DBPs), such as nitrosamines, halonitromethanes and haloacetonitriles, from reactions between chlorine/chloramine and dissolved organic nitrogen in drinking water has caused great concern with regarding public health. This study revealed the occurrence of 17 aliphatic amines, some of which have been confirmed to be the precursors of N-DBPs, in source water across China. A sensitive method based on benzenesulfonyl chloride derivatization and liquid-liquid extraction followed by GC-MS analysis was established for the simultaneous analysis of the selected amines in aqueous samples. In total, 37 source water samples from the capital cities of 20 provinces were collected for the survey. Among the 17 amines, 14 were detected with an average frequency of detection of 36%. The most relevant amines in terms of frequency and maximum concentrations detected were dimethylamine (100%, 24.82 μg/L), methylamine (78%, 0.92 μg/L), N-methylethylamine (70%, 8.84 μg/L), propylamine (59%, 10.69 μg/L), diethylamine (54%, 3.76μg/L), N-methylbutylamine (35%, 3.07 μg/L), N-ethylpropylamine (35%, 0.52μg/L), and piperidine (32%, 2.35 μg/L). This is the first large scale survey of the aliphatic amines occurrence in source water in the world. The wide presence of nitrosamine precursors like dimethylamine, N-methylethylamine and diethylamine, and the precursors of haloacetonitriles and halonitromethanes like methylamine and propylamine suggests that better source water management is required to ensure the safety of drinking water.展开更多
Herein,we report tunable asymmetric addition and telomerization of butadiene by synergistic chiral primary amine/achiral palladium catalysis.A selection of different achiral phosphine ligand in concert with the chiral...Herein,we report tunable asymmetric addition and telomerization of butadiene by synergistic chiral primary amine/achiral palladium catalysis.A selection of different achiral phosphine ligand in concert with the chiral primary amine-trifluoromethanesulfonic acid(TfOH)conjugates enables both chemo-and enantioselective control of the coupling with butadiene.Bidentate[(oxydi-2,1-phenylene)-bis-(diphenylphosphine)](DPEPhos)ligand led to 1,4-addition adduct whereas monodentate(p-Tol)3P ligand gave the telomerization product.A range ofα-branchedβ-ketoesters and aldehydes could be applied to afford allylation or telomerization products bearing allcarbon quaternary centers at high efficiency and good chemo-,regio-,and stereoselectivities.展开更多
Ion-absorbed rare earth ores radioactive residues(IREORR)are a class of waste residue from the production of rare earth elements(REEs).Because of its radioactive dose,IREORR are usually stored in waste warehouses.IREO...Ion-absorbed rare earth ores radioactive residues(IREORR)are a class of waste residue from the production of rare earth elements(REEs).Because of its radioactive dose,IREORR are usually stored in waste warehouses.IREORR are difficult to be disposed of.However,it contains relatively high concentrations of REEs,which can be considered as a valuable secondary resource.In this paper,a novel process is developed for the separation of thorium(Th)and recovery of REEs from IREORR hydrochloric acid leachate with primary amine N1923 and Cyanex?572,respectively.The effects of sulfate concentration,extractant concentration and pH on N1923 extraction in hydrochloric acid solution were investigated in detail.The results show that the extraction capacity of N1923 can be improved by adding sulfate to the solution and increasing the concentration of N1923.Acidity has little effect on the extraction of Th when pH is higher than 1.As for the stripping,REEs are more easily stripped from loaded organic phase than Th,and nitric acid is a better stripping agent than hydrochloric acid.Combined with the extraction of Cyanex■572 for REEs,a fractional extraction experiment for separating Th and enriching of REEs was performed.The yield of Th is higher than 99.9%and the concentration of REEs is enriched to 183.84 g/L.展开更多
文摘In order to resolve the increasing resistance phenomena of the Gram-negative bacteria against single chain quaternary ammonium salts (QAS), lysine with a pedant fluorinated bis-ammonium salts was synthesized and its antimicrobial properties were evaluated in this work. The novel fluorinated bis-ammonium salts shows similar activity with conventional single chain quaternary ammonium salts against Gram-positive bacteria but stronger activity against Gram-negative bacteria and yeast compared with the single chained counterpart.
文摘The synergistic extraction of Cd(Ⅱ)with primary amine N-1923 and neutral organophosphorus reagents(TBP,DBBP,B)from hydrochloric acid has been investigated at μ=0.5,t=25℃.The compositions of the synergistic extraction complexes and the mechanism of the synergistic extraction have been determined by the methods of slope and constant mole. The synergistic extraction complexes with composition(RNH_3Cl)_2·CdCl_2·B have been demonstrated.The synergistic extraction reactions and additional reaction of Cd(Ⅱ)have been proposed as follows: CdCl_2+2RNH_3Cl_(o)+B_(o)(RNH_3Cl)_2·CdCl_2·B_(o) (RNH_3Cl)_3·CdCl_(2(o)+B_(o)(RNH_3Cl)_2·CdCl_2·B_(o)+RNH_3Cl_(o) In addition,the equilibrium constants and the thermodynamic functions of the synergistic ex- traction reactions have been calculated.The IR and NMR spectra of the synergistic ext-ac- tion complexes of Cd(Ⅱ)have been studied as well.
文摘Mechanism of extraction of Fe (III) from sulphate solution by primary amine N1923 and stripping of Fe loaded organic phase with dilute H_2SO_4 was investigated. The organic phase was characterized by FT-IR and photon correlation spectroscopy. The composition of extracted species as well as the content of H_2O in organic phase were determined. The dependence of both the rate of extraction and stripping on the formation of reverse micelle in primary amine (N1923)system has been confirmed. It is shown that the extraction of Fe(III) by primary amine sulphate may be related to the adduct formation or cation exchange reaction under different concentrations of H_2SO_4 in aqueous solution.
基金the Natural Science Foundation of China(21861132003 and 22031006)Tsinghua University Initiative Scientific Research Program for financial support.
文摘Direct alkylation with skipped enynes or cyclopropropylacetylenes represents an ideal process for the installation of pentadienyl group in terms of atom- and step-economy.The development of catalytic asymmetric versions has been frequently pursued and most of the successes have been achieved with enolizable aldehydes.We herein describe a synergistic chiral primary amine/Pd catalysis for asymmetric α-pentadienylation of β-ketocarbonyls and aldehydes with skipped enynes or cyclopropropylacetylenes.The reaction features the construction of acyclic all-carbon quaternary centers with high enantioselectivity,and good functional group tolerance and scalability.
基金National Natural Science Foundation of China,Grant/Award Number:21788102Research Grants Council of Hong Kong,Grant/Award Numbers:16307020,16306620,16305518,N_HKUST609/19,C6009-17G,C6014-20w+1 种基金Innovation and Technology Commission,Grant/Award Numbers:ITC-CNERC14SC01,ITCPD/17-9Natural Science Foundation of Guangdong Province,Grant/Award Number:201913121205002。
文摘Specific bioconjugation for native primary amines is highly valuable for both chemistry and biomedical research.Despite all the efforts,scientists lack a proper strategy to achieve high selectivity for primary amines,not to mention the requirement of fast response in real applications.Herein,we report a chromone-based aggregation-induced emission(AIE)fluorogen called CMVMN as a self-reporting bioconjugation reagent for selective primary amine identification,and its applications for monitoring bioprocesses of amination and protein labeling.CMVMN is AIE-active and capable of solid-state sensing.Thus,its electrospun films are manufactured for visualization of amine diffusion and leakage process.CMVMN also shows good biocompatibility and potential mitochondria-staining ability,which provides new insight for organelle-staining probe design.Combined with its facile synthesis and good reversibility,CMVMN would not only show wide potential applications in biology,but also offer new possibilities for molecular engineering.
基金ProjectsupportedbytheNaturalScienceFoundationofShandongProvince (No .Y2 0 0 0B0 3)
文摘It has been found that the two-phase reactions of aqueous HCl, HOAc or H_3PO_4 with primary amine N_ 1923 in chloroform are oscillating reactions. Their power-time curves were measured by the titration microcalorimetric method, and the induction period (t_ in). The first oscillating period (t_ p.1) and the second oscillating period (t_ p.2) were determined. The apparent activating parameters and the orders of the oscillating systems were calculated and the following relationships were established: for the oscillating system of hydrochloric acid t_ in∝c 0.147_ HClexp(1.35×10 3T), t_ p.1∝c 0.241_ HCl· exp(4.33×10 3T), t_ p.2∝c 0.290_ HClexp(5.59×10 3T); for the oscillating system of acetic acid, t_ in∝c 0.883_ HOAcexp(2.32×10 3T), t_ p.1∝c 0.399_ HOAc· exp(4.50×10 3T), t_ p.2∝c 0.301_ HOAcexp(5.88×10 3T); for the oscillating system of phosphoric acid, t_ in∝c 1.14_ H_3PO_4exp(7.70×10 4T), t_ p.1∝c 1.42_ H_3PO_4exp(1.14×10 4T), t_ p.2∝c 1.47_ H_3PO_4exp(1.27×10 4T).
文摘A novel, convenient and efficient approach to the synthesis of pyrrole and imidazole derivatives via the reaction between primary amines, alkyl propiolates or isothiocyanate and oxalyl chloride is described. The method offers several advantages including high yields of products and performing reaction under solvent-free conditions.
基金ProjectsupportedbytheNationalNaturalScienceFoundationofChina (No .2 0 172 0 18) theExcellentScientistFoundationofAnhuiProvince (No .2 0 0 10 40 ) +1 种基金theNaturalScienceFoundationoftheEducationDepartmentofAnhuiProvince (No .2 0 0 2kj2 5 4ZD) theSci e
文摘A microwave enhanced, solventless Mannich condensation of terminal alkynes, primary amines with paraformaldehyde on cuprous iodide doped alumina has been investigated. The structures of products depend on the ratio of alkyne to amine and paraformaldehyde.
基金financial support from the National Natural Science Foundation of China (No. 21262022)
文摘An intramolecular organocatalytic enantioselective aza-Michael reaction of carbamates, sulfonamides and acetamides to a,b-unsaturated ketones was developed. This process is promoted by 9-amino-9-deoxy-epi-quinine and diphenyl hydrogen phosphate to afford a straightforward and expeditious synthesis of several synthetically useful five-and six-membered heterocycles with excellent enantioselectivity(92%–97.5% ee) and very good yields(up to 99%).
基金National Natural Science Foundation of China(NSFC Nos.21390400,21521002 and 21502198)the Ministry of Science and Technology,Chinese Academy of Sciences(No.QYZDJSSW-SLH023)for generous financial supportsupported by National Program for Support of Top-notch Young Professionals,CAS Youth Innovation Promotion Association and CAS onehundred talented program(D)
文摘We report herein the first example of asymmetric hydroazidation of α-substituted vinyl ketones by using chiral primary amines as the catalysts.A simple chiral primary-tertiary diamine catalyst derived from lphenylalanine was found to readily promote this aza-Michael addition reaction with enamine protonation as the key stereogenic step,thus enabling the effective synthesis of α-chiral β-azido ketones with good yields and moderate enantioselectivities.
基金This work is supported by the National Natural Science Foundation of China(No.21677098)Shanghai government(Nos.19SG42,19520710700 and 18230742500)the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning(No.TP2016034).
文摘A primary amine functionalized ordered mesoporous phenolic resin(NH2-MPR)was obtained by an evaporationinduced self-assembly method.The as-prepared NH2-MPR material possessed large surface area and ordered twodimensional hexagonal mesoporous structure.Also,the amine groups were well-dispersed in the mesoporous channels.It can act as an efficient solid base to promote Knoevenagel condensation of various aldehydes with ethyl cyanoacetate in water with high conversion and selectivity.This excellent performance was attributed ordered mesopores and hydrophobic pore surface,which resulted in the decreased the interference of water solvent and the increased active sites accessibility.Noted that it was comparable with homogenous base catalysts in the water-medium Knoevenagel condensation reaction,and it can be reused for at least five times without significant reduction in the catalytic efficiency.
基金Supported by the National Natural Science Foundation of China(No.20572058)
文摘The oxidative coupling of primary aromatic amines was investigated. Ce(SO4)2 can mediate the oxidative coupling of primary aromatic amines in water to dimers, trimers and/or tetramers, which depended on the substituents of primary aromatic amines. When 2,6-dimethylaniline or 2,6-diethylaniline was used as substrate, dimer, and tetramer were formed as major products. When 2,6-diisopropylaniline or 2,6-dihaloanilines was used as substrate, dimer, and trimer were formed. The mechanistic aspect was also investigated.
基金This research was made possible as a result of a generous grant from NSFC(grant nos.21971101 and 22171127)Guangdong Basic and Applied Basic Research Foundation(grant no.2022A1515011806)+3 种基金Department of Education of Guangdong Province(grant nos.2022JGXM054 and 2021KTSCX106)Shenzhen Science and Technology Innovation Committee(grant no.JCYJ20220519201425001)Thousand Talents Program for Young Scholars,The Pearl River Talent Recruitment Program(grant no.2019QN01Y261)Guangdong Provincial Key Laboratory of Catalysis(grant no.2020B121201002).
文摘Sterically congestedα-tertiary primary amines are ubiquitous substructures in pharmaceutical and agrochemical agents yet are challenging to access.Herein,straightforward photoredox-catalyzed access to structurally diverseα,α,α-trisubstituted primary amines from denitrogenative alkylarylation or dialkylation of vinyl azides with N-hydroxyphthalimide(NHPI)esters and cyanoarenes or aryl aldehydes has been developed.The use of vinyl azide as a precursor to a primary aminewas enabled by the dual role of the Hantzsch ester to form an electron donor-acceptor complex and serve as a sacrificial reductant.This strategy provides a modular synthesis ofα-tertiary primary amines,including unprotected 1,2-amino alcohols,from simple materials with excellent functional group tolerance.The synthetic applicability of this method was demonstrated by streamlined access to 2,2-disubstituted tetrahydroquinolines.Preliminary investigations support two parallel reductive photocatalytic cycles allowing for the denitrogenative alkylarylation or dialkylation of vinyl azides via decarboxylative radical addition followed by heteroradical cross-coupling betweenα-amino radicals and aryl anion radicals or ketyl anion radicals.
基金sponsored by the Foundation for the Author of National Excellent Doctoral Dissertation of PR China (NO.200346)Program for New Century Excellent Talents in University (NCET-04-0270)National Natural Science Foundation of China (NO.20406005)
文摘Wormlike/lamellar microporous carbons were prepared by using long alkyl chain primary amine hydrochloride as the template and resorci- nol/formaldehyde as the carbon source under highly acidic conditions. The template can be eliminated by high temperature treatment under an inert atmosphere. The obtained carbon materials were characterized by N2 adsorption-desorption, transmission electron microscopy, ther- mogravimetry and scanning electron microscopy. The results show that dodecylamine hydrochloride surfactant can be used as the template of wormlike micropores structure while octadecylamine hydrochloride results in both lamellar and wormlike micropores. The obtained carbon materials have the similar pore size in the range of 0.5-0.59 nm, but with various morphologies such as monolith, spheres, and coralline. The microporous carbon obtained from dodecylamine hydrochloride surfactant shows good adsorption performance to remove the refractory sulfur compounds and nitrogen-containing compounds in fuel.
基金supported financially by the National Natural Science Foundation of China(No.90713045)the National 863 Program of China(No.2006AA020501)Basic scientific research foundation of IMM,CAMS(No. 2007ZD03)
文摘An unexpected reaction of 10-bromomethyl-12-oxocalanolide A(2) with primary amine was demonstrated and studied. Consequentially,a new method for the preparation of N-substituted pyrroles starting fromγ-halo-α,β-unsaturated ketone was presented.
基金the National Natural Science Foundation of China(No.21502006)Beijing National Laboratory for Molecular Sciences and Beijing Institute of Technology(BIT)for financial support。
文摘Direct C(sp3)-H functionalization of N-unprotected aliphatic amines represents one of the most efficient and straightforward strategies for amine synthesis.Despite some recent progress in this field,the NH2-directed y-C(sp3)-H arylation of primary aliphatic amines exceptα-amino esters remained an unmet challenge.In this report,we established a simple and efficient method for site-selective C(sp3)-H arylation of primary aliphatic amines by aryl iodides.In the presence of only 5 mol%Pd(OAc)2,a wide range of aliphatic amines including O-benzyl and O-silyl amino alcohols were arylated at y-orδ-positions by aryl iodides containing a broad scope of functional groups.The synthetic application of this method had also been demonstrated by large-scale synthesis,the synthesis of a fingolimod analogue,and the conjugation with natural D-menthol and fluorescent 1,8-naphthalimide.
基金supported by the National Natural Science Foundation of China (No.21077118)the National Special Funding Project for Water Pollution Control and Management of China (No.2009ZX07419-001)
文摘The formation of toxic nitrogenous disinfection byproducts (N-DBPs), such as nitrosamines, halonitromethanes and haloacetonitriles, from reactions between chlorine/chloramine and dissolved organic nitrogen in drinking water has caused great concern with regarding public health. This study revealed the occurrence of 17 aliphatic amines, some of which have been confirmed to be the precursors of N-DBPs, in source water across China. A sensitive method based on benzenesulfonyl chloride derivatization and liquid-liquid extraction followed by GC-MS analysis was established for the simultaneous analysis of the selected amines in aqueous samples. In total, 37 source water samples from the capital cities of 20 provinces were collected for the survey. Among the 17 amines, 14 were detected with an average frequency of detection of 36%. The most relevant amines in terms of frequency and maximum concentrations detected were dimethylamine (100%, 24.82 μg/L), methylamine (78%, 0.92 μg/L), N-methylethylamine (70%, 8.84 μg/L), propylamine (59%, 10.69 μg/L), diethylamine (54%, 3.76μg/L), N-methylbutylamine (35%, 3.07 μg/L), N-ethylpropylamine (35%, 0.52μg/L), and piperidine (32%, 2.35 μg/L). This is the first large scale survey of the aliphatic amines occurrence in source water in the world. The wide presence of nitrosamine precursors like dimethylamine, N-methylethylamine and diethylamine, and the precursors of haloacetonitriles and halonitromethanes like methylamine and propylamine suggests that better source water management is required to ensure the safety of drinking water.
基金the Natural Science Foundation of China(nos.21672217,21861132003,and 22031006)Tsinghua University Initiative Scientific Research Program for financial support.
文摘Herein,we report tunable asymmetric addition and telomerization of butadiene by synergistic chiral primary amine/achiral palladium catalysis.A selection of different achiral phosphine ligand in concert with the chiral primary amine-trifluoromethanesulfonic acid(TfOH)conjugates enables both chemo-and enantioselective control of the coupling with butadiene.Bidentate[(oxydi-2,1-phenylene)-bis-(diphenylphosphine)](DPEPhos)ligand led to 1,4-addition adduct whereas monodentate(p-Tol)3P ligand gave the telomerization product.A range ofα-branchedβ-ketoesters and aldehydes could be applied to afford allylation or telomerization products bearing allcarbon quaternary centers at high efficiency and good chemo-,regio-,and stereoselectivities.
基金supported by the National Key R&D Program of China(2017YFE0106900)Science and Technology Major Project of Ganzhou(2018)Fujian Program for High-Level Entrepreneurial and Innovative Talents Introduction and Science and Technology Service Network Initiative from Chinese Academy of Sciences。
文摘Ion-absorbed rare earth ores radioactive residues(IREORR)are a class of waste residue from the production of rare earth elements(REEs).Because of its radioactive dose,IREORR are usually stored in waste warehouses.IREORR are difficult to be disposed of.However,it contains relatively high concentrations of REEs,which can be considered as a valuable secondary resource.In this paper,a novel process is developed for the separation of thorium(Th)and recovery of REEs from IREORR hydrochloric acid leachate with primary amine N1923 and Cyanex?572,respectively.The effects of sulfate concentration,extractant concentration and pH on N1923 extraction in hydrochloric acid solution were investigated in detail.The results show that the extraction capacity of N1923 can be improved by adding sulfate to the solution and increasing the concentration of N1923.Acidity has little effect on the extraction of Th when pH is higher than 1.As for the stripping,REEs are more easily stripped from loaded organic phase than Th,and nitric acid is a better stripping agent than hydrochloric acid.Combined with the extraction of Cyanex■572 for REEs,a fractional extraction experiment for separating Th and enriching of REEs was performed.The yield of Th is higher than 99.9%and the concentration of REEs is enriched to 183.84 g/L.