4-hydroxybenzoic acid was synthesized by one pot method using polymer-bonded β-aminopropionic acid-2-β-cyclodextrin as a catalyst.by which the selectivity for 4-hydroxybenzoic acid is 87%. A possible carboxylation m...4-hydroxybenzoic acid was synthesized by one pot method using polymer-bonded β-aminopropionic acid-2-β-cyclodextrin as a catalyst.by which the selectivity for 4-hydroxybenzoic acid is 87%. A possible carboxylation mechanism in the presence of the title catalyst is discussed. Also.the recovery and reusage of the catalyst is studied.展开更多
Controllable syntheses of different-sized gold nanoclusters are of great significance for their fundamental science and practical applications. In this work, we achieve the controllable and selective syntheses of Au7 ...Controllable syntheses of different-sized gold nanoclusters are of great significance for their fundamental science and practical applications. In this work, we achieve the controllable and selective syntheses of Au7 and Au13 clusters through adding HCl to the traditional Aull synthetic route at different reaction time. Time-dependent mass spectra and UV- Vis spectra were ernployed to monitor these two HCl-directed processes, and revealed the distinct roles of HCl as an etchant or a growth prornotor, respectively. Furthermore, parallel experiments on independent synthetic routes involving only non-chlorine H＋ （acetic acid） or Cl （tetraethy larnrnoniurn chloride） instead of HCl were perforrned, which illustrated the main role of H^＋-etching and Cl^ -assisted growth in HCl-directed cluster synthetic routes. We propose the HCl-etching is mainly achieved via the H＋ action to break the Au（I）-PPh3 part of clusters, while the HCl-prornoted growth is realized via the attachment of Au-Cl species to the pre-forrned clusters.展开更多
A novel protocol was developed for the construction of highly functionalized pyridin-2(1H)-ones from 3-formylchromones,ethyl 2-(pyridin-2-yl)acetate derivatives and amines via a complex multicomponent cascade reaction...A novel protocol was developed for the construction of highly functionalized pyridin-2(1H)-ones from 3-formylchromones,ethyl 2-(pyridin-2-yl)acetate derivatives and amines via a complex multicomponent cascade reaction involving targeted duplicated ring-opening and duplicated cyclization reactions which form skeleton-reorganized target compounds.A series of pyridin-2(1H)-ones were produced by this reaction accompanied by the formation of three bonds(one C–N and two C–C bonds)and the cleavage of one bond in one step.This protocol can be used in combinatorial and parallel syntheses of various pyridin-2(1H)-ones with potent biological activity.The advantages of this approach include simple and practical operation(multicomponent one-pot),high yields(up to 91%),and products with potential biological activity.展开更多
E)-α-Aryltellurenylvinylstannanes have been synthesized stereoselectively via the hydrozirconation of alkynyl- stannanes, followed by the reactions with aryltellurenyl iodides. (E)-α-Aryltellurenylvinylstannanes ca...E)-α-Aryltellurenylvinylstannanes have been synthesized stereoselectively via the hydrozirconation of alkynyl- stannanes, followed by the reactions with aryltellurenyl iodides. (E)-α-Aryltellurenylvinylstannanes can undergo sequential cross coupling reactions with both electrophiles and nucleophiles in the presence of transition metal complexes to form two carbon-carbon bonds in the same olefinic carbon leading to trisubstituted alkenes stereose- lectively.展开更多
A novel protocol was developed for the construction of highly functionalized 2-(diarylphosphoryl)-1,2-dihydropyridine derivatives(DAPDHPs)from 3-formylchromones(1),heterocyclic ketene aminals(HKAs,2),and phosphine oxi...A novel protocol was developed for the construction of highly functionalized 2-(diarylphosphoryl)-1,2-dihydropyridine derivatives(DAPDHPs)from 3-formylchromones(1),heterocyclic ketene aminals(HKAs,2),and phosphine oxides(R_(2)P(O)H,3)via a novel,one-pot cascade reaction.Optimization of the reaction conditions determined that refluxing the mixture of the 3-formylchromones,HKAs,and various R_(2)P(O)H in propylene carbonate(PC)in the presence of triethylamine as a base facilitated the highest yields of the DAPDHP products.This cascade reaction,which involved the cleavage of one C-O bond in the 3-formylchromone substrates and the formation of three new bonds(one C-C,one C-N,and one C-P bond),enabled the synthesis of a small library of DAPDHP products.The dearomatized DAPDHP products were formed by the regioselective nucleophilic addition of the R_(2)P(O)H reagents to the intermediate pyridinium salts 8.This approach has several advantages such as the use of an environmentally-friendly solvent,simple and practical operation(with filtration and washing without column chromatography separation),good yields,and a product with potential biological activity.展开更多
A new type of cyclodextrin dimers (2a-c) bridged with multidentate coordination units has been synthesized by treatment of 6-deoxy-6-hydroxyethylamino-beta-cyclodextrin 1 with corresponding dibromides in the presence ...A new type of cyclodextrin dimers (2a-c) bridged with multidentate coordination units has been synthesized by treatment of 6-deoxy-6-hydroxyethylamino-beta-cyclodextrin 1 with corresponding dibromides in the presence of base.展开更多
The reaction of the reduced Schiff base HL（N-（4-hydroxybenzyl）-L-serine） with Zn（CH3COO）2·2H2O in aqueous solution afforded [Zn（L）2]·3H2O（I）. The complex has been characterized by elemental analysi...The reaction of the reduced Schiff base HL（N-（4-hydroxybenzyl）-L-serine） with Zn（CH3COO）2·2H2O in aqueous solution afforded [Zn（L）2]·3H2O（I）. The complex has been characterized by elemental analysis, FT-IR, powder X-ray diffraction, electrospray ionization mass spectrometry and single-crystal X-ray diffraction. Complex I crystallizes in the orthorhombic system, space group P212121, with a=9.197（2）, b=10.445（2）, c=24.149（5） , V=2319.8（8） 3, Z=4, C（20）H（30）N2O11 Zn, Mr=539.83, Dc=1.546 g·cm3, μ=1.122 mm（-1）, F（000）=1128, GOOF=0.971, the final R=0.0206 and w R=0.0506 for 4346 observed reflections（I ＆gt; 2σ（I））. In complex I, each Zn（II） ion coordinates with three carboxyl oxygen atoms and two amine nitrogen atoms from three L-anions, forming a distorted five-coordinated trigonal bipyramidal geometry. Complex I exhibits a 1D wavy chain structure that is extended by hydrogen-bonding interactions to form a supramolecular network. The bioactivity of the complex as a potential PTPs inhibitor in vitro was investigated, displaying potent inhibition against PTP1B（IC（50）, 0.24 μM） and TCPTP（IC（50）, 0.53 μM） with a moderate selectivity.展开更多
The use of nanostructured composites as catalyst supports is a promising route to prepare catalysts with high selectivity and productivity. In this work, reduced graphene oxide-TiO_2(rGP-x) composites with a variation...The use of nanostructured composites as catalyst supports is a promising route to prepare catalysts with high selectivity and productivity. In this work, reduced graphene oxide-TiO_2(rGP-x) composites with a variation of reduced graphene oxide(rGO) content were synthesized by hydrothermal method. Pd/rGP-x catalysts were prepared in incipient-wetness impregnation method for the direct synthesis of H_2O_2 from H2 and O_2. The morphology and electronic properties of catalysts were investigated by XPS, TEM, and Raman spectroscopy.The ratio of Pd^(2+)/Pd^0 and the hydrophobicity of the catalysts were increased with the rising content of rGO. As the amount of rGO in the catalysts varied in the range of 0.025 wt%–2 wt%, the selectivity of H_2O_2 exhibited a tendency of increasing firstly and then decreasing from 0.1 wt% to 2 wt%. It indicates that good catalytic performance for H_2O_2 synthesis can be achieved only when appropriate amount of rGO is introduced. The H_2O_2 selectivity and productivity of Pd/r GP-0.025 both improved remarkably compared with Pd/P25. This enhancement originated from the combined effects of the proper ratio of Pd^(2+)/Pd^0 and hydrophobicity of the catalyst.展开更多
Converting hydrocarbons into aldehydes in a green and environmentally benign way is of great signif-icance in fine chemistry.In this work,all-inorganic Cs_(3)Bi_(2)B_(9) perovskite nanoparticles were uniformly loaded ...Converting hydrocarbons into aldehydes in a green and environmentally benign way is of great signif-icance in fine chemistry.In this work,all-inorganic Cs_(3)Bi_(2)B_(9) perovskite nanoparticles were uniformly loaded on BiOBr nanosheets via an in-situ growth method,which can selectivity photoactivate aromatic C(sp3)-H bond of toluene to generate benzaldehyde.According to the in-situ X-ray photoelectron spec-troscopy characterization,the photogenerated electrons of BiOBr transfer to Cs_(3)Bi_(2)B_(9) enforced by the in-ternal electric field under light irradiation,resulting in S-scheme heterojunction.Furthermore,theoretical calculations indicate that toluene molecules are inclined to adsorb on the BiOBr surface,subsequently in-volving the oxidation reaction to generate benzyl radical(PhCH_(2)·)by using the energetic holes of BiOBr,while the remaining photoinduced electrons in the conduction band(CB)of Cs_(3)Bi_(2)B_(9) with powerful reduction ability reduce O2 into·O_(2)^(-),which is the vital oxidative active species working on toluene selective oxidation process.Such an unexceptionable charge carrier utilization mode and tendentious ad-sorption behavior of reactants contribute to the optimized Cs_(3)Bi_(2)B_(9)/BiOBr heterojunction with excellent photocatalytic performance,achieving a maximum of 22.5%toluene conversion and 96.2%selectivity to-wards benzaldehyde formation.This work provides a rational photocatalyst heterojunction construction protocol for the selective oxidation of saturated aromatic C-H bonds.展开更多
Environmental concerns have highlighted the need of cleaner technologies. A cleaner, convenient and selective technology has been developed for the preparation of 3-(4,6-dimethoxy-pyrimidin-2-yloxy)-2-methyl-phenol (...Environmental concerns have highlighted the need of cleaner technologies. A cleaner, convenient and selective technology has been developed for the preparation of 3-(4,6-dimethoxy-pyrimidin-2-yloxy)-2-methyl-phenol (DPMP) from 2-methyl-benzene-1,3-diol in water as solvent. The isolated yield of DPMP is up to 86% in good selectivity. The product structure was characterized by conventional methods, H-NMR and MS. This technology belongs to the modern concept of 1 environmentally friendly low wastes or non-wastes technology (LWNWT).展开更多
Cu2O nanocubes and Cu nanoparticles were prepared by reducing Cu（ Ⅱ ） salt with ethanol as the reducing agent and solvent in the presence of multidentate ligand poly（vinylpyrrolidone） （PVP） under different cond...Cu2O nanocubes and Cu nanoparticles were prepared by reducing Cu（ Ⅱ ） salt with ethanol as the reducing agent and solvent in the presence of multidentate ligand poly（vinylpyrrolidone） （PVP） under different conditions. The morphologies and the crystalline structures of the products were characterized by using scanning electron microscopy （SEM）, transmission electron microscopy（TEM）, selected-area electron diffraction（ SAED）, and powder X-ray diffraction（XRD）. In particular, the influences of the solvothennal reaction temperature and alkalinity on the products were investigated. A lower temperature and a lower alkali concentration favor the formation of the Cu2O phase, whereas a higher temperature and a higher alkali concentration generally lead to the formation of the Cu phase.展开更多
A condition-controlled strategy for selectively synthesis of 2-acylbenzothiazoles and bibenzo[b][1,4]thiazines from aryl methyl ketones and disulfanediyldianilines was realized using I_(2)/DMSO or I_(2)/MeCN systems,r...A condition-controlled strategy for selectively synthesis of 2-acylbenzothiazoles and bibenzo[b][1,4]thiazines from aryl methyl ketones and disulfanediyldianilines was realized using I_(2)/DMSO or I_(2)/MeCN systems,respectively.The desired products were synthesized in only 15 min with moderate to excellent yields(50%-90%)under microwave-assisted,metal-free conditions.The strategy provides a great advantage for selective synthetic applications in the efficient synthesis of benzothiazoles and bibenzothiazines heterocycle compounds.展开更多
An efficient synthesis of functionalized 4H-chromenes by the tandem reaction of β,γ-unsaturated α- ketoesters with 2-naphthols, 1 -naphthols, and 1,3-dihydroxynaphthalenes has been accomplished with high selectivit...An efficient synthesis of functionalized 4H-chromenes by the tandem reaction of β,γ-unsaturated α- ketoesters with 2-naphthols, 1 -naphthols, and 1,3-dihydroxynaphthalenes has been accomplished with high selectivity and excellent yields in the presence of a catalytic amount of bismuth triflate [Bi（OTf）3, 5 mol%] under mild conditions. The functionalized 4H-chromene synthesis and our previous 2H- chromene hemiacetal synthesis could complement each other to enrich reaction diversity.展开更多
A novel and simple cyanide chemosensor 2-（naphthalen-1-ylmethylene）malononitrile（L） was designed and synthesized via a green chemistry method in water without using any catalyst.The chemosensor showed an excellent...A novel and simple cyanide chemosensor 2-（naphthalen-1-ylmethylene）malononitrile（L） was designed and synthesized via a green chemistry method in water without using any catalyst.The chemosensor showed an excellent sensitivity and selectivity for CN in aqueous solution.The detection limit could be as low as 1.6×10~7 moI/L（0.16μmol/L）,which is far lower than the WHO guideline of 1.9μmol/L cyanide for drink water.展开更多
文摘4-hydroxybenzoic acid was synthesized by one pot method using polymer-bonded β-aminopropionic acid-2-β-cyclodextrin as a catalyst.by which the selectivity for 4-hydroxybenzoic acid is 87%. A possible carboxylation mechanism in the presence of the title catalyst is discussed. Also.the recovery and reusage of the catalyst is studied.
基金supported by the National Natural Science Foundation of China (No.11475176, No.U1632263, and No.21533007)the Foundation for Innovative Research Groups of the National Natural Science Foundation of China (No.11621063)
文摘Controllable syntheses of different-sized gold nanoclusters are of great significance for their fundamental science and practical applications. In this work, we achieve the controllable and selective syntheses of Au7 and Au13 clusters through adding HCl to the traditional Aull synthetic route at different reaction time. Time-dependent mass spectra and UV- Vis spectra were ernployed to monitor these two HCl-directed processes, and revealed the distinct roles of HCl as an etchant or a growth prornotor, respectively. Furthermore, parallel experiments on independent synthetic routes involving only non-chlorine H＋ （acetic acid） or Cl （tetraethy larnrnoniurn chloride） instead of HCl were perforrned, which illustrated the main role of H^＋-etching and Cl^ -assisted growth in HCl-directed cluster synthetic routes. We propose the HCl-etching is mainly achieved via the H＋ action to break the Au（I）-PPh3 part of clusters, while the HCl-prornoted growth is realized via the attachment of Au-Cl species to the pre-forrned clusters.
基金support from the Natural Science Foundation of Yunnan Province(No.2019FY003003)the National Natural Science Foundation of China(No.21662042)the Scientific and Technological Innovation Team of Green Synthesis and Activity Research of Natural-like Heterocyclic Compound Libraries in Universities of Yunnan Province(No.C17624011121).
文摘A novel protocol was developed for the construction of highly functionalized pyridin-2(1H)-ones from 3-formylchromones,ethyl 2-(pyridin-2-yl)acetate derivatives and amines via a complex multicomponent cascade reaction involving targeted duplicated ring-opening and duplicated cyclization reactions which form skeleton-reorganized target compounds.A series of pyridin-2(1H)-ones were produced by this reaction accompanied by the formation of three bonds(one C–N and two C–C bonds)and the cleavage of one bond in one step.This protocol can be used in combinatorial and parallel syntheses of various pyridin-2(1H)-ones with potent biological activity.The advantages of this approach include simple and practical operation(multicomponent one-pot),high yields(up to 91%),and products with potential biological activity.
基金Project supported by the National Natural Science Foundation of China (No. 20062002).
文摘E)-α-Aryltellurenylvinylstannanes have been synthesized stereoselectively via the hydrozirconation of alkynyl- stannanes, followed by the reactions with aryltellurenyl iodides. (E)-α-Aryltellurenylvinylstannanes can undergo sequential cross coupling reactions with both electrophiles and nucleophiles in the presence of transition metal complexes to form two carbon-carbon bonds in the same olefinic carbon leading to trisubstituted alkenes stereose- lectively.
基金We are grateful for financial support from the Natural Science Foundation of Yunnan Province(Nos.2019fy003003 and 2017fa003)the National Natural Science Foundation of China(No.21662042)Scientific and Technological Innovation Team of Green Synthesis and Activity Research of Natural-like Heterocyclic Compound Libraries in Universities of Yunnan Province.Authors thank advanced analysis and measurement center of Yunnan University for the sample testing service.
文摘A novel protocol was developed for the construction of highly functionalized 2-(diarylphosphoryl)-1,2-dihydropyridine derivatives(DAPDHPs)from 3-formylchromones(1),heterocyclic ketene aminals(HKAs,2),and phosphine oxides(R_(2)P(O)H,3)via a novel,one-pot cascade reaction.Optimization of the reaction conditions determined that refluxing the mixture of the 3-formylchromones,HKAs,and various R_(2)P(O)H in propylene carbonate(PC)in the presence of triethylamine as a base facilitated the highest yields of the DAPDHP products.This cascade reaction,which involved the cleavage of one C-O bond in the 3-formylchromone substrates and the formation of three new bonds(one C-C,one C-N,and one C-P bond),enabled the synthesis of a small library of DAPDHP products.The dearomatized DAPDHP products were formed by the regioselective nucleophilic addition of the R_(2)P(O)H reagents to the intermediate pyridinium salts 8.This approach has several advantages such as the use of an environmentally-friendly solvent,simple and practical operation(with filtration and washing without column chromatography separation),good yields,and a product with potential biological activity.
文摘A new type of cyclodextrin dimers (2a-c) bridged with multidentate coordination units has been synthesized by treatment of 6-deoxy-6-hydroxyethylamino-beta-cyclodextrin 1 with corresponding dibromides in the presence of base.
基金Supported by NNSFC(Nos.21271121,21471092,21571118)
文摘The reaction of the reduced Schiff base HL（N-（4-hydroxybenzyl）-L-serine） with Zn（CH3COO）2·2H2O in aqueous solution afforded [Zn（L）2]·3H2O（I）. The complex has been characterized by elemental analysis, FT-IR, powder X-ray diffraction, electrospray ionization mass spectrometry and single-crystal X-ray diffraction. Complex I crystallizes in the orthorhombic system, space group P212121, with a=9.197（2）, b=10.445（2）, c=24.149（5） , V=2319.8（8） 3, Z=4, C（20）H（30）N2O11 Zn, Mr=539.83, Dc=1.546 g·cm3, μ=1.122 mm（-1）, F（000）=1128, GOOF=0.971, the final R=0.0206 and w R=0.0506 for 4346 observed reflections（I ＆gt; 2σ（I））. In complex I, each Zn（II） ion coordinates with three carboxyl oxygen atoms and two amine nitrogen atoms from three L-anions, forming a distorted five-coordinated trigonal bipyramidal geometry. Complex I exhibits a 1D wavy chain structure that is extended by hydrogen-bonding interactions to form a supramolecular network. The bioactivity of the complex as a potential PTPs inhibitor in vitro was investigated, displaying potent inhibition against PTP1B（IC（50）, 0.24 μM） and TCPTP（IC（50）, 0.53 μM） with a moderate selectivity.
基金Supported by the National Key Basic Research Program of China(2013CB733505,2013CB733501)the National Natural Science Foundation of China(91334202)+2 种基金the Natural Science Foundation of Jiangsu Province of China(BK2012421,BK20130062)the Research Fund for the Doctoral Program of Higher Education of China(20123221120015)the Project for Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘The use of nanostructured composites as catalyst supports is a promising route to prepare catalysts with high selectivity and productivity. In this work, reduced graphene oxide-TiO_2(rGP-x) composites with a variation of reduced graphene oxide(rGO) content were synthesized by hydrothermal method. Pd/rGP-x catalysts were prepared in incipient-wetness impregnation method for the direct synthesis of H_2O_2 from H2 and O_2. The morphology and electronic properties of catalysts were investigated by XPS, TEM, and Raman spectroscopy.The ratio of Pd^(2+)/Pd^0 and the hydrophobicity of the catalysts were increased with the rising content of rGO. As the amount of rGO in the catalysts varied in the range of 0.025 wt%–2 wt%, the selectivity of H_2O_2 exhibited a tendency of increasing firstly and then decreasing from 0.1 wt% to 2 wt%. It indicates that good catalytic performance for H_2O_2 synthesis can be achieved only when appropriate amount of rGO is introduced. The H_2O_2 selectivity and productivity of Pd/r GP-0.025 both improved remarkably compared with Pd/P25. This enhancement originated from the combined effects of the proper ratio of Pd^(2+)/Pd^0 and hydrophobicity of the catalyst.
基金National Natural Science Foundation of China(Nos.21905209,52171145,and 51973078)Natural Science Foundation of Xinjiang Uygur Autonomous Region(No.2020D01B25).
文摘Converting hydrocarbons into aldehydes in a green and environmentally benign way is of great signif-icance in fine chemistry.In this work,all-inorganic Cs_(3)Bi_(2)B_(9) perovskite nanoparticles were uniformly loaded on BiOBr nanosheets via an in-situ growth method,which can selectivity photoactivate aromatic C(sp3)-H bond of toluene to generate benzaldehyde.According to the in-situ X-ray photoelectron spec-troscopy characterization,the photogenerated electrons of BiOBr transfer to Cs_(3)Bi_(2)B_(9) enforced by the in-ternal electric field under light irradiation,resulting in S-scheme heterojunction.Furthermore,theoretical calculations indicate that toluene molecules are inclined to adsorb on the BiOBr surface,subsequently in-volving the oxidation reaction to generate benzyl radical(PhCH_(2)·)by using the energetic holes of BiOBr,while the remaining photoinduced electrons in the conduction band(CB)of Cs_(3)Bi_(2)B_(9) with powerful reduction ability reduce O2 into·O_(2)^(-),which is the vital oxidative active species working on toluene selective oxidation process.Such an unexceptionable charge carrier utilization mode and tendentious ad-sorption behavior of reactants contribute to the optimized Cs_(3)Bi_(2)B_(9)/BiOBr heterojunction with excellent photocatalytic performance,achieving a maximum of 22.5%toluene conversion and 96.2%selectivity to-wards benzaldehyde formation.This work provides a rational photocatalyst heterojunction construction protocol for the selective oxidation of saturated aromatic C-H bonds.
文摘Environmental concerns have highlighted the need of cleaner technologies. A cleaner, convenient and selective technology has been developed for the preparation of 3-(4,6-dimethoxy-pyrimidin-2-yloxy)-2-methyl-phenol (DPMP) from 2-methyl-benzene-1,3-diol in water as solvent. The isolated yield of DPMP is up to 86% in good selectivity. The product structure was characterized by conventional methods, H-NMR and MS. This technology belongs to the modern concept of 1 environmentally friendly low wastes or non-wastes technology (LWNWT).
基金Supported by the National Natural Science Foundation of China(Nos. 20331010 and 90406002) and Specialized ResearchFund for the Doctoral Program of Higher Education(No. 20030007014).
文摘Cu2O nanocubes and Cu nanoparticles were prepared by reducing Cu（ Ⅱ ） salt with ethanol as the reducing agent and solvent in the presence of multidentate ligand poly（vinylpyrrolidone） （PVP） under different conditions. The morphologies and the crystalline structures of the products were characterized by using scanning electron microscopy （SEM）, transmission electron microscopy（TEM）, selected-area electron diffraction（ SAED）, and powder X-ray diffraction（XRD）. In particular, the influences of the solvothennal reaction temperature and alkalinity on the products were investigated. A lower temperature and a lower alkali concentration favor the formation of the Cu2O phase, whereas a higher temperature and a higher alkali concentration generally lead to the formation of the Cu phase.
基金financially supported by the National Natural Science Foundation of China(No.21871125)the Natural Science Foundation of Shandong Province,China(Nos.ZR2019MB043 and ZR2019QB022)the Construction Project of Quality Curriculum for Postgraduate Education of Shandong Province(No.SDYKC19057).
文摘A condition-controlled strategy for selectively synthesis of 2-acylbenzothiazoles and bibenzo[b][1,4]thiazines from aryl methyl ketones and disulfanediyldianilines was realized using I_(2)/DMSO or I_(2)/MeCN systems,respectively.The desired products were synthesized in only 15 min with moderate to excellent yields(50%-90%)under microwave-assisted,metal-free conditions.The strategy provides a great advantage for selective synthetic applications in the efficient synthesis of benzothiazoles and bibenzothiazines heterocycle compounds.
基金supported by the Science and Technology Development Project of Weihai (Nos.2011DXGJ13,2012DXGJ02)the Natural Science Foundation of Shandong Province (No.ZR2012BM002)the National Natural Science Foundation of China (Nos.21202028,21372054)
文摘An efficient synthesis of functionalized 4H-chromenes by the tandem reaction of β,γ-unsaturated α- ketoesters with 2-naphthols, 1 -naphthols, and 1,3-dihydroxynaphthalenes has been accomplished with high selectivity and excellent yields in the presence of a catalytic amount of bismuth triflate [Bi（OTf）3, 5 mol%] under mild conditions. The functionalized 4H-chromene synthesis and our previous 2H- chromene hemiacetal synthesis could complement each other to enrich reaction diversity.
基金supported by the National Natural Science Foundation of China(NSFC)(Nos.21064006,21161018, 21262032)the Natural Science Foundation of Gansu Province (No.1010RJZA018)the Program for Changjiang Scholars and Innovative Research Team in University of Ministry of Education of China(No.IRT1177)
文摘A novel and simple cyanide chemosensor 2-（naphthalen-1-ylmethylene）malononitrile（L） was designed and synthesized via a green chemistry method in water without using any catalyst.The chemosensor showed an excellent sensitivity and selectivity for CN in aqueous solution.The detection limit could be as low as 1.6×10~7 moI/L（0.16μmol/L）,which is far lower than the WHO guideline of 1.9μmol/L cyanide for drink water.
