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
The selectivity for monomethylamine plus dimethylamine is desired to be improved in the selective synthesis of methylamines due to their high value as chemical intermediates.ZK-5,a small-pore zeolite,shows high select...The selectivity for monomethylamine plus dimethylamine is desired to be improved in the selective synthesis of methylamines due to their high value as chemical intermediates.ZK-5,a small-pore zeolite,shows high selectivity for monomethylamine plus dimethylamine,while conventional synthetic methods of ZK-5 involve a long crystallization time and/or expensive organic structure-directing agents/explosive nitrates.展开更多
Presented herein is a condition-controlled selective synthesis of CF_(3)-chromene and CF_(3)-benzofuran based on the reaction of N-phenoxyacetamide and CF_(3)-ynone.When the reaction is carried out in MeOH under the c...Presented herein is a condition-controlled selective synthesis of CF_(3)-chromene and CF_(3)-benzofuran based on the reaction of N-phenoxyacetamide and CF_(3)-ynone.When the reaction is carried out in MeOH under the catalysis of Rh(III),CF_(3)-chromene is formed via C—H metalation-initiated alkenylation,acetamide group migration and intramolecular oxo-nucleophilic addition.On the other hand,when the reaction is run in DMSO under the promotion of CsOAc,CF_(3)-benzofuran is generated via aza-Michael addition-initiated[3,3]-σrearrangement,intramolecular oxo-nucleophilic addition and water elimination.To our knowledge,this is the first report on the selective construction of chromene or benzofuran scaffold along with introduction of a CF_(3) unit from the same starting materials.The methodology was scalable and the products could be readily transformed into other valuable products.Moreover,the products thus obtained possess decent anticancer activity.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 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 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...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
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(sp^(3))-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
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
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
Nitrile hydrogenation represents an atom-economical and green approach to yield the highly valueadded primary amines,which suffers from harsh conditions and serious selectivity challenges.Herein,we demonstrated Pd nan...Nitrile hydrogenation represents an atom-economical and green approach to yield the highly valueadded primary amines,which suffers from harsh conditions and serious selectivity challenges.Herein,we demonstrated Pd nanoparticles anchored on ultrathin plate-like porous magnesium hydrate(Mg(OH)_(2))supports for the highly selective synthesis of benzylamine from benzonitrile hydrogenation in the absence of additives at 30℃.展开更多
The rare molecular structures and application possibilities in a variety of fields has attracted the attention to molecular knots and catenanes in recent years.However,their selective synthesis remains a major challen...The rare molecular structures and application possibilities in a variety of fields has attracted the attention to molecular knots and catenanes in recent years.However,their selective synthesis remains a major challenge.Herein,a new diimidazole-based flexible ligand precursor L1 possessing two phenyl conjugated groups and two methylene moieties has been synthesized.In addition,five half-sandwich-based building units(B1–B5)featuring different sizes and functional groups were selected to combine with compound L1 for generating different molecular knots and catenanes,by following a classical coordination-driven self-assembly strategy.Thus,one double trefoil knot,two trefoil knots,one D-type[2]catenane and one metallamacrocycle have been isolated in remarkable yields.Interestingly,the D-type[2]catenane 2 could be converted into metallamacrocycle 1 upon light irradiation and introduction of Cl−ions.The formation of all the indicated structures has been unequivocally confirmed by single-crystal X-ray diffraction analysis,NMR spectroscopy and ESI-TOF-MS.Photothermal conversion studies showed that the double trefoil knot 5 exhibits remarkable photothermal conversion efficiency in near-infrared(NIR)experiments(31.32%–40.28%),which can be attributed to its unique topological structure andπ–πstacking interactions.Electron paramagnetic resonance(EPR)experiments fully confirmed the recorded results.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
The selection and optimization of synthesis routes for porous metal-organic materials are critical for their large-scale manufacture but remain largely underexplored.In this study,we compare mechanochemistry vs.slurry...The selection and optimization of synthesis routes for porous metal-organic materials are critical for their large-scale manufacture but remain largely underexplored.In this study,we compare mechanochemistry vs.slurry vs.solution methods for the synthesis of a 1D chain coordination polymer{[Co(bpy)(NCS)_(2)(H_(2)O)_(2)]·bpy}n(chn-1-Co-NCS-H_(2)O)that is an intermediate to the 2D switching coordination network[Co(bpy)_(2)(NCS)_(2)]n,sql-1-Co-NCS(1=bpy=4,4′-bipyridine).Although neat mechanosynthesis using Co(NCS)_(2) and bpy as the starting materials failed,both water slurry and water-assisted mechanochemical syntheses afforded the desired intermediate,chn-1-Co-NCS-H_(2)O,in high yield.Nevertheless,the resulting sql-1-Co-NCS products were observed to exhibit different CO_(2)sorption profiles depending on the synthesis methods used to prepare chn-1-Co-NCS-H_(2)O.This study reveals that water can play an important role in mechanosynthesis,not only by inducing and accelerating the reaction process,but also by enhancing product quality in a manner that is not readily detectable by PXRD.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financial support from the National Key Research and Development Program of China(2021YFA1500401 and 2021YFA1501202)the National Natural Science Foundation of China(U1967215,21835002,21621001,21991091,and 21875221)the 111 Project(B17020).
文摘The selectivity for monomethylamine plus dimethylamine is desired to be improved in the selective synthesis of methylamines due to their high value as chemical intermediates.ZK-5,a small-pore zeolite,shows high selectivity for monomethylamine plus dimethylamine,while conventional synthetic methods of ZK-5 involve a long crystallization time and/or expensive organic structure-directing agents/explosive nitrates.
基金the Program for Science&Technology Innovation Talents in Universities of Henan Province(24HASTIT069)Postdoctoral Research Grant in Henan Province(HN2022041)+1 种基金Key Research Projects of Universities in Henan Province(24A150018)NMPA Key Laboratory for Research and Evaluation of Innovative Drug,Henan Key Laboratory of Organic Functional Molecules and Drug Innovation,and 111 Project(D17007)for financial support.
文摘Presented herein is a condition-controlled selective synthesis of CF_(3)-chromene and CF_(3)-benzofuran based on the reaction of N-phenoxyacetamide and CF_(3)-ynone.When the reaction is carried out in MeOH under the catalysis of Rh(III),CF_(3)-chromene is formed via C—H metalation-initiated alkenylation,acetamide group migration and intramolecular oxo-nucleophilic addition.On the other hand,when the reaction is run in DMSO under the promotion of CsOAc,CF_(3)-benzofuran is generated via aza-Michael addition-initiated[3,3]-σrearrangement,intramolecular oxo-nucleophilic addition and water elimination.To our knowledge,this is the first report on the selective construction of chromene or benzofuran scaffold along with introduction of a CF_(3) unit from the same starting materials.The methodology was scalable and the products could be readily transformed into other valuable products.Moreover,the products thus obtained possess decent anticancer activity.
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.
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This project(No.29632004)is supported by the National Natural Science Foundation of Chinathe Special Funds of the State Educational Committee for Doctorate Scientific Research.
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(sp^(3))-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.
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.
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supported by the National Natural Science Foundation of China(21872109 and 22002115)the Fundamental Research Funds for the Central Universities(D5000210283,D5000210601 and D5000210829)+2 种基金S.Zhang is also supported by the Guangdong Basic and Applied Basic Research Foundation(2022B1515020092)the Young Elite Scientists Sponsorship Program by CAST(2019QNRC001)Technology and the support of the National Natural Science Foundation of China(Grant No:22038011).
文摘Nitrile hydrogenation represents an atom-economical and green approach to yield the highly valueadded primary amines,which suffers from harsh conditions and serious selectivity challenges.Herein,we demonstrated Pd nanoparticles anchored on ultrathin plate-like porous magnesium hydrate(Mg(OH)_(2))supports for the highly selective synthesis of benzylamine from benzonitrile hydrogenation in the absence of additives at 30℃.
基金supported by the National Natural Science Foundation of China(No.22471113 and 22171123)the Natural Science Foundation for Excellent Young Scholars of Henan Province(No.242300421139 and 232300421083)+2 种基金the Science and Technology Innovation Talent Program of University in Henan Province(No.25HASTIT001)Henan Center for Outstanding Overseas Scientists(GZS2024020)the Heluo Young Talent Lifting Project(2023HLTJ02).
文摘The rare molecular structures and application possibilities in a variety of fields has attracted the attention to molecular knots and catenanes in recent years.However,their selective synthesis remains a major challenge.Herein,a new diimidazole-based flexible ligand precursor L1 possessing two phenyl conjugated groups and two methylene moieties has been synthesized.In addition,five half-sandwich-based building units(B1–B5)featuring different sizes and functional groups were selected to combine with compound L1 for generating different molecular knots and catenanes,by following a classical coordination-driven self-assembly strategy.Thus,one double trefoil knot,two trefoil knots,one D-type[2]catenane and one metallamacrocycle have been isolated in remarkable yields.Interestingly,the D-type[2]catenane 2 could be converted into metallamacrocycle 1 upon light irradiation and introduction of Cl−ions.The formation of all the indicated structures has been unequivocally confirmed by single-crystal X-ray diffraction analysis,NMR spectroscopy and ESI-TOF-MS.Photothermal conversion studies showed that the double trefoil knot 5 exhibits remarkable photothermal conversion efficiency in near-infrared(NIR)experiments(31.32%–40.28%),which can be attributed to its unique topological structure andπ–πstacking interactions.Electron paramagnetic resonance(EPR)experiments fully confirmed the recorded results.
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support of Science Foundation Ireland(16/IA/4624)the Irish Research Council(IRCLA/2019/167).
文摘The selection and optimization of synthesis routes for porous metal-organic materials are critical for their large-scale manufacture but remain largely underexplored.In this study,we compare mechanochemistry vs.slurry vs.solution methods for the synthesis of a 1D chain coordination polymer{[Co(bpy)(NCS)_(2)(H_(2)O)_(2)]·bpy}n(chn-1-Co-NCS-H_(2)O)that is an intermediate to the 2D switching coordination network[Co(bpy)_(2)(NCS)_(2)]n,sql-1-Co-NCS(1=bpy=4,4′-bipyridine).Although neat mechanosynthesis using Co(NCS)_(2) and bpy as the starting materials failed,both water slurry and water-assisted mechanochemical syntheses afforded the desired intermediate,chn-1-Co-NCS-H_(2)O,in high yield.Nevertheless,the resulting sql-1-Co-NCS products were observed to exhibit different CO_(2)sorption profiles depending on the synthesis methods used to prepare chn-1-Co-NCS-H_(2)O.This study reveals that water can play an important role in mechanosynthesis,not only by inducing and accelerating the reaction process,but also by enhancing product quality in a manner that is not readily detectable by PXRD.
