A photoinduced intramolecular charge transfer complex(ICTC)-enabled photoreduction of trifluoromethyl phosphonium salt for the trifluoromethylation of heteroarenes was developed.It offers a convenient approach to intr...A photoinduced intramolecular charge transfer complex(ICTC)-enabled photoreduction of trifluoromethyl phosphonium salt for the trifluoromethylation of heteroarenes was developed.It offers a convenient approach to introduce trifluoromethyl group to a wide range of aromatic heterocycles,such as indoles,pyrrole,substituted benzene,coumarin,and chromone.This strategy provides operational simplicity,photocatalyst-,transition metal-,and oxidant-free conditions,making it highly advantageous.展开更多
Recently, tetrakis(hydroxymethyl)phosphonium sulfate(THPS) was found to play an important role in the sludge pretreatment process. However, the effects of THPS pretreatment on the characteristics of sewage sludge are ...Recently, tetrakis(hydroxymethyl)phosphonium sulfate(THPS) was found to play an important role in the sludge pretreatment process. However, the effects of THPS pretreatment on the characteristics of sewage sludge are still insufficiently understood.The properties of sludge after pretreatment with different concentrations of THPS were investigated in this study. The results showed that pH, dewatering ability, and particle size of sludge decreased with increase in THPS concentration. The volatile suspended solids(VSS) and total suspended solids(TSS) of sludge also decreased slightly with increase in THPS concentration. The specific oxygen uptake rate(SOUR) results suggested that lower THPS concentrations(≤ 1.87 mg/g VSS) enhanced the activity of sludge, but higher concentrations(≥ 1.87 mg/g VSS) inhibited it. Gram-negative bacteria with peritrichous flagellation(such as Pseudomonas, Escherichia, and Faecalibacterium) were extremely sensitive to THPS. The decrease in specific most probable numbers(MPNs) of pathogens(total coliforms and Escherichia coli) with the increase in THPS concentration also proved the sterilization ability of THPS in the sludge pretreatment process. Pretreatment of sludge with concentrations of THPS higher than 37.41 mg/g VSS would meet the pathogen requirements for land application of Class A biosolids.展开更多
Tetra-hydroxymethyl phosphonium chloride （THPC） has been considered as an important chrome-free tanning agent. To understand the THPC tanning mechanism, the structure, charge distribution, activity and tanning abili...Tetra-hydroxymethyl phosphonium chloride （THPC） has been considered as an important chrome-free tanning agent. To understand the THPC tanning mechanism, the structure, charge distribution, activity and tanning ability of each phosphorous compound in THPC tanning system were studied, by ^31p NMR, FT-IR spectroscopy, differential scanning calorimetry （DSC） and computational chemistry method, etc. When pH raised to 6.0, the decomposition of THPC would take place, which results in a production of free formaldehyde, tri-hydroxymethyl phosphonium （TrHP） and tri-hydroxymethyl phosphine oxide （TrHPO）. At pH 9.0, THPC will be converted completely to TrHP and most TrHP is further oxidized into TrHPO. It is possible that, in reaction of phosphorous compounds and collagens, both P-C and C-O bonds would break simultaneously or individually. From molecular charge distribution and bond polar properties, it is deduced that, if P-C bonds break, the activity is in order of TrHPO 〉 THPC 〉 TrHE whereas if C--O bonds break, the order is TrHP 〉 THPC 〉 TrHPO. It is more possible that P--C bonds will break in reaction with collagen, and TrHPO may be more active in the THPC tanning system. The results of tanning and DSC also prove the above conclusion. Furthermore, the fact that the shrinkage temperature of THPC tanned leather was below 70℃ when basified to pH 5.0 or lower suggests that the hydroxymethyl groups of THPC and TrHP are less possible to combine directly with amino groups of collagen.展开更多
Well-defined polycarbonate diol was successfully synthesized through a strategy using a combination of organocatalyst and water.Such strategy was less developed in organocatalyzed polymerization and frequently regarde...Well-defined polycarbonate diol was successfully synthesized through a strategy using a combination of organocatalyst and water.Such strategy was less developed in organocatalyzed polymerization and frequently regarded as side reactions.Herein,one-component phosphonium borane Lewis pairs PB1-PB8 were successfully applied in the copolymerization of CO_(2) and cyclohexene oxide(CHO)to generate poly(CHO-alt-CO_(2))carbonate(PCHC).Parameters of linker length and counter anion effects on the catalyst activity were investigated.It was found that Lewis pair PB3 served as a dual initiator and catalyst in the copolymerization of CHO and CO_(2) with or without the presence of water.In contrast,Lewis pair PB8 can serve as a true catalyst for the preparation of well-definedα,ω-hydroxyl PCHC diols.This was achieved by introducing a labile CF3COO group as counter anion through anion exchange reaction while water molecules acted as chain transfer agents.The function of trifluoroacetate group in the polymerization process was investigated in detail and possible mechanism was proposed.Upon changing the amount of water and catalyst loading,PCHC diols with varied molecular weight(1.5 kg/mol to 7.5 kg/mol),low dispersities(D<1.2)and carbonate content(>99%)could be easily obtained.The low molecular weight PCHC diol was used as a bifunctional macroinitiator for the ring-opening polymerization of L-lactide(LLA)to afford ABA triblock copolymer in one-pot synthesis.展开更多
Both of quaternary ammonium and quaternary phosphonium salts of bis-hydroxyethyl terephthalate （BHET） were successfully synthesized and characterized by fourier transform infrared spectroscopy （FT-IR）. These two k...Both of quaternary ammonium and quaternary phosphonium salts of bis-hydroxyethyl terephthalate （BHET） were successfully synthesized and characterized by fourier transform infrared spectroscopy （FT-IR）. These two kinds of salts were used to intercalate Na-MMT to yield two kinds of respective organo-modified MMTs. Basal spacing and thermal stability were investigated by using X-ray diffraction （XRD） and thermogravimetric analysis （TGA）, respectively. The experimental results show that, as compared with Na-MMT, basal spacings of both of MMTs modified by the quaternary phosphonium salt of BHET （BHETPP） and the quaternary ammonium salt of BHET （BHEA）, increase from 12.4 A to 19.7/k and 31.3 A, respec-tively. Thermal stability of BHETPP-modified MMT is much better than that of BHEA-modified MMT, i e, T otof BHETPP-modified MMT is around 400℃ while Tcmset of BHEA-modified MMT is near 250℃. Therefore, with en-larged basal spacing and excellent thermal stability, BHETPP-modified MMT is a promising organo-modified MMT which may be used to prepare polyethylene terephthalate/MMT nanocomposite with high thermal and mechanical performance.展开更多
Na-montruorillonite （Na-MMT） was exchanged with three quaternary atkylphosphonium salts： decyl tributylphosphonium bromide （DTBPBr）, dodecyl tributylphosphonium bromide （DDTBPBr） and hexadecyl tributylphosphoni...Na-montruorillonite （Na-MMT） was exchanged with three quaternary atkylphosphonium salts： decyl tributylphosphonium bromide （DTBPBr）, dodecyl tributylphosphonium bromide （DDTBPBr） and hexadecyl tributylphosphonium bromide （HDTBPBr）, to investigate the effects of phosphonium salts species and relative molecular mass on the characteristics, morphology, thermal stability and long-acting antibacterial property of phosphonium montmorillonites. The resulting modified montmorillonites were characterized by the FTIR, XRD, TEM, and TG/DTG techniques. And minimum inhibitory concentration （MIC） was used to investigate antibacterial activity. The results show that the phosphonium salts are intercalated into Na-MMT, and the basal spacing of P-MMTs is enlarged with the increase of phosphonium salt content or the growth of alkyl chain length. DDTBP-MMT-3 with 19.83% （mass fraction of dodecyl tributylphosphonium salts, displays excellent thermal stability and long-acting antibacterial activity.展开更多
ByBimolecular Nucleophilic Substitution, four new types of alkylene triphenyl double quaternary phosphonium salt were synthesized respectively by using triphenylphosphine, 1,3-dibromopropane, 1,6-dibromohexane,1,10-di...ByBimolecular Nucleophilic Substitution, four new types of alkylene triphenyl double quaternary phosphonium salt were synthesized respectively by using triphenylphosphine, 1,3-dibromopropane, 1,6-dibromohexane,1,10-dibromo- decane, 1,12-dibromododecane as raw materials and using DMAC as the solvent, under a certain temperature and reac- tion time. The productivity is 58% - 83%. The molecular structures of the products were characterized by IR, NMR and elemental analysis. The sterilizing effect of 1,6-hexylidene triphenyl double phosphonium bromide(HTDPB) and 1,12- dodecylidene triphenyl double phosphonium bromide(DoTDPB) was evaluated by using extinct dilution method.The experimental result shows that the sterilizing effect of DoTDPB is better than the effect of HTDPB under the same drug concentration and contact time. When the concentration of DoTDPB was 20 mg/L and the contact time was 0.5 h, the sterilizing rate of DoTDPB used to kill saprophytic bacteria (TGB), sulfate-reducing bacteria (SRB) and iron bacteria (IB) was 95.56%, 84% and 99.58% respectively.展开更多
The phosphine-functionalized phosphonium-based ionic liquids(dppm-Q, dppe-Q, dppp-Q and dppb-Q) as the bi-functional ligands enable the efficient one-pot tandem hydroformylationeacetalization. It was found that, in dp...The phosphine-functionalized phosphonium-based ionic liquids(dppm-Q, dppe-Q, dppp-Q and dppb-Q) as the bi-functional ligands enable the efficient one-pot tandem hydroformylationeacetalization. It was found that, in dppm-Q, dppe-Q, dppp-Q and dppb-Q, the incorporated phosphino-fragments were responsible for Rh-catalyzed hydroformylation and the phosphoniums were in charge of the subsequent acetalization as the Lewis acid catalysts. Moreover, the diphosphonium-based ionic liquid of dppb-DQ could be applied as a co-solvent to immobilize the Rh/dppb-Q catalytic system with the advantages of the improved catalytic performance, the available catalyst recyclability, and the wide generality for the substrates.展开更多
Phosphonium or arsonium salt 1 can undergo the tandem reaction of deprotonation -oxidation-Wittig reaction with alcohol 2 in the presence of sodium hydroxide and manganese dioxide, which affords a general simplified m...Phosphonium or arsonium salt 1 can undergo the tandem reaction of deprotonation -oxidation-Wittig reaction with alcohol 2 in the presence of sodium hydroxide and manganese dioxide, which affords a general simplified method for the stereoselective synthesis of (E)- a, b-unsaturated esters 3.展开更多
Microbial contamination in water has emerged as a critical concern and thus developing biocide materials for controlling microbial contamination is crucial.Removing all pathogenic bacteria in water is difficult when u...Microbial contamination in water has emerged as a critical concern and thus developing biocide materials for controlling microbial contamination is crucial.Removing all pathogenic bacteria in water is difficult when using traditional water treatment technologies.Moreover,these bacteria can easily reproduce during pipeline distribution.In this work,a facile and effective chitosan derivative biocide denoted as PCC was developed by grafting with quaternary phosphonium salt(QPS).PCC became positively charged with a wide range of p H and demonstrated antibacterial activity up to 95%and 100%against Escherichia coli and Staphylococcus aureus as model pathogens,respectively.The grafting of QPS may disrupt the cell membrane and lead to bacterial inactivation,as demonstrated by the scanning electron microscopy image and the concentration of intracellular substance leakage.MTT assay results indicate that PCC achieved good biocompatibility with negligible in vitro cytotoxicity.These findings introduce a promising approach for bacterial decontamination due to its low cytotoxicity and high biocidal activity.展开更多
Chemoselective,living/controlled polymerizations of allyl methacrylate(AMA) and vinyl methacrylate(VMA) with/without methyl methacrylate(MMA) by using the phosphonium ylide/organoaluminum based Lewis pairs(LPs) have b...Chemoselective,living/controlled polymerizations of allyl methacrylate(AMA) and vinyl methacrylate(VMA) with/without methyl methacrylate(MMA) by using the phosphonium ylide/organoaluminum based Lewis pairs(LPs) have been realized.The P-ylide-2/AIMe(BHT)_(2)(Pylide-2=Ph_(3)P=CHMe and BHT=2,6-iBu_(2)-4-MeC_(6)H_(2)O) was demonstrated to be superior by which homopolymers PAMAs(M_(n)=27.6-111.5kg/mol and ■=1.14-1.25) and PVMAs(M_(n)=28.4-78.4 kg/mol and ■=1.12-1.18) and block copolymers PMMA-b-PAMA,PAMA-b-PVMA,PAMA-bPMMA,PMMA-b-PAMA-b-PMMA,PAMA-b-PMMA-b-PAMA,and PAMA-b-PVMA-b-PAMA were synthesized.In the polymerizations,all of the monomers were reacted by the conjugated ester vinyl groups leaving intactly the nonconjugated acryloxy groups.The pendant acryloxy groups attached to the main chain enable further to post-functionalization by the AIBN-induced radical "thiol-ene" reaction using PhCH_(2)SH.The thiolether side group-containing polymers PAMA-SCH_(2)Ph and PAMA-SCH_(2)Ph-b-PMMA-b-PAMA-SCH_(2)Ph were thus prepared.展开更多
A charge transfer complex(CTC)-enabled photoreduction of ether phosphonium salts for the generation of oxyalkyl radicals was described.The photoreduction provides a convenient method to achieve selective oxyalkylation...A charge transfer complex(CTC)-enabled photoreduction of ether phosphonium salts for the generation of oxyalkyl radicals was described.The photoreduction provides a convenient method to achieve selective oxyalkylation of enamides with broad substrate scope.The method features operational simplicity,mild and inherent green conditions.展开更多
[ Objective] To understand the toxicity and sterilization effects of the tetrakis hydroxmethyl phosphonium sulfate （THPS） as a novel quatemary phosphonium biocide. [ Method] Under hydrostatic conditions, the acute t...[ Objective] To understand the toxicity and sterilization effects of the tetrakis hydroxmethyl phosphonium sulfate （THPS） as a novel quatemary phosphonium biocide. [ Method] Under hydrostatic conditions, the acute toxicity and bactericidal property of THPS on the Fiexibacter coiumnaris （ F. columnaris） were observed in Japanese eel. The semi-lethal concentration （LCso）, safe concentration （Sc）, minimum inhibitory concentration （MIC）, minimum bactericidal concentration （MBC） and the sterilization rate of THPS were calculated, respectively. [ Result ] The LCso of THPS at 24, 48 and 96 h were 11.9, 9.9 and 9.1 mg/L, respectively. The Sc of THPS at 24 h was 2.1 mg/L; the MIC and MBC of THPS to the F. columnaris were 0.36 and 0.72 mg/L; and the sterilization rate was 100% at a concentration of 0.7 mg/L at 12 h. The sterilization rate of THPS had no great change with pH values varying from 5.5 to 9.5. [ Condusion] The THPS is a novel, safe and effective biocide for prevention and treatment of bacterial diseases of Japanese eel.展开更多
Synthesis of terpolymers consisting of two electron-donating monomers, viz. styrene and vinyl acetate with one electron-accepting monomer, i.e. acrylonitrile, initiated by p-nitrobenzyl triphenyl phosphonim ylide in d...Synthesis of terpolymers consisting of two electron-donating monomers, viz. styrene and vinyl acetate with one electron-accepting monomer, i.e. acrylonitrile, initiated by p-nitrobenzyl triphenyl phosphonim ylide in dioxane as diluent at 65°C for 150 min has been studied. The kinetic expression is Rpα[I]0.8[Sty] 1.2[VA] 1.4 [AN]1.2. The terpolymer composition was determined by the Kelen-Tüdos method. The values of reactivity ratios using r1 (Sty + VA) = 0.1 and r2 (AN) = 0.005. The overall activation energy is 46 kJ●mol●L–1. The formation of terpolymer is confirmed by the FTIR spectra showing bands at 3030 cm–1, 1598 cm–1, and 2362 cm–1, confirming the presence of phenyl, acetoxy and nitrile group respectively. The terpolymer has been characterized by 1H-Nuclear Magnetic Resonance, 13C-Nuclear Magnetic Resonance. The Differential Scanning Calorimetric curve shows the Tg of the polymer as 149.5°C. A scanning electron microscope confirms the polymer to be phosphorus free. Electron.Spin.Resonance spectra confirms phenyl radical responsible for initiation.展开更多
A study of the quenching of pyrene fluorescence by a series of alkyltriphenylphosphonium bromides indi- cated the coiling conformation of ionic surfactant in aqueous solution.Formation of pyrene excimer in cetyltriph-...A study of the quenching of pyrene fluorescence by a series of alkyltriphenylphosphonium bromides indi- cated the coiling conformation of ionic surfactant in aqueous solution.Formation of pyrene excimer in cetyltriph- enylphosphonium solution strengthened the conclusion.展开更多
Quaternary phosphonium salts （QPS） with reactive groups used as antibacterial agents are promising which could be covalently linked to inert polymer surfaces by in situ polymerization. In this work, two kinds of qua...Quaternary phosphonium salts （QPS） with reactive groups used as antibacterial agents are promising which could be covalently linked to inert polymer surfaces by in situ polymerization. In this work, two kinds of quaternary phosphonium salts with hydroxyl groups were synthesized successfully. Characterization of these two quaternary phosphonium salts was performed by the Fourier transform infrared spectroscopy （FT-IR） and nuclear magnetic resonance （NMR） spectrometry. The thermal stability and antibacterial activity of antibacterial agents were also investigated by using thermo-gravimetric analysis, differential scanning calorimetry （TG-DSC） and agar diffusion method. The test results showed that these two QPS exhibited good thermal stability and excellent antibacterial activity against both bacteria： Staphylococcus aureus and Escherichia coll.展开更多
In this study was to investigate, by phase-transfer catalysis, the activity of single and mixed ammonium and phosphonium salts grafted on a 揼el-type?styrene-7% divinylbenzene copolymer in the oxidation of benzyl alco...In this study was to investigate, by phase-transfer catalysis, the activity of single and mixed ammonium and phosphonium salts grafted on a 揼el-type?styrene-7% divinylbenzene copolymer in the oxidation of benzyl alcohol with hydrogen peroxide. A wide variety of catalysts with different quaternary groups and different quaternary chain length substituents were examined. The activity of single 搊nium?salts increases as a consequence of the association of ammonium and phosphonium salts grafted on the same polymeric support. The activity of polymer-supported ammonium and phosphonium salts increases with the number of carbon atoms contained in the alkyl radicals of the onium and of the functionalization degree with phosphonium groups.展开更多
A systematic study on the synthesis and antibacterial activity of the quaternary "onium" salts grafted on an insoluble "gel-type" styrene-7% divinylbenzene copolymer by polymer-analogous reactions ...A systematic study on the synthesis and antibacterial activity of the quaternary "onium" salts grafted on an insoluble "gel-type" styrene-7% divinylbenzene copolymer by polymer-analogous reactions is showed. Antibacterial activity of quaternary ammonium and/or phosphonium salts grafted on polymer-supports has been studied against Staphylococcus aureus and Escherichia coli. A wide variety of "onium" salts bound to macromolecular supports with different quaternary groups and different quaternary chain length substituents were examined. The antibacterial activity of mixed "onium" salts increases as a consequence of the association of ammonium and phosphonium salts grafted on the same polymeric support.展开更多
Phosphorus-containing functional materials have diverse applications in optoelectronics and bioscience owing to their unique properties.However,polycyclicπ-conjugated phosphonium salts have been rarely explored due t...Phosphorus-containing functional materials have diverse applications in optoelectronics and bioscience owing to their unique properties.However,polycyclicπ-conjugated phosphonium salts have been rarely explored due to their complex synthesis.In this work,a facile and efficient method for constructing polycyclicπ-conjugated phosphonium salts(TBPIMe derivatives)is proposed,based on the photocyclization of phosphindolium salts(TPPIMe derivatives).Systematic experimental and theoretical investigations reveal the changed photophysical and photochemical properties when TPPIMe derivatives are converted to TBPIMe derivatives.Notably,the novel polycyclicπ-conjugated phosphonium salt p-MOTBPIMe exhibits improved reactive oxygen species generation ability and much stronger specific affinity toward DNA than phosphindolium salts p-MOTPPIMe.Moreover,in vitro experiments demonstrate that p-MOTPPIMe can also be efficiently converted into p-MOTBPIMe under 405 nm laser irradiation in living cells,accompanied by the migration from cytoplasm to nucleus to enhance the photodynamic effect.Additionally,p-MOTBPIMe shows superior antibacterial activity against not only Gram-positive drug-resistant bacteria but also fungi,by leveraging both dark and light cytotoxicity.This work opens up a new chemical toolkit for novel polycyclicπ-conjugated phosphonium salts,which are promising for developing advanced theranostic agents with satisfactory accuracy and efficacy.展开更多
文摘A photoinduced intramolecular charge transfer complex(ICTC)-enabled photoreduction of trifluoromethyl phosphonium salt for the trifluoromethylation of heteroarenes was developed.It offers a convenient approach to introduce trifluoromethyl group to a wide range of aromatic heterocycles,such as indoles,pyrrole,substituted benzene,coumarin,and chromone.This strategy provides operational simplicity,photocatalyst-,transition metal-,and oxidant-free conditions,making it highly advantageous.
基金supported by the Major Science and Technology Program for Water Pollution Control and Treatment of China (No. 2017ZX07106003)the National Natural Science Foundation of China (Nos. 51378492 and 51308068)
文摘Recently, tetrakis(hydroxymethyl)phosphonium sulfate(THPS) was found to play an important role in the sludge pretreatment process. However, the effects of THPS pretreatment on the characteristics of sewage sludge are still insufficiently understood.The properties of sludge after pretreatment with different concentrations of THPS were investigated in this study. The results showed that pH, dewatering ability, and particle size of sludge decreased with increase in THPS concentration. The volatile suspended solids(VSS) and total suspended solids(TSS) of sludge also decreased slightly with increase in THPS concentration. The specific oxygen uptake rate(SOUR) results suggested that lower THPS concentrations(≤ 1.87 mg/g VSS) enhanced the activity of sludge, but higher concentrations(≥ 1.87 mg/g VSS) inhibited it. Gram-negative bacteria with peritrichous flagellation(such as Pseudomonas, Escherichia, and Faecalibacterium) were extremely sensitive to THPS. The decrease in specific most probable numbers(MPNs) of pathogens(total coliforms and Escherichia coli) with the increase in THPS concentration also proved the sterilization ability of THPS in the sludge pretreatment process. Pretreatment of sludge with concentrations of THPS higher than 37.41 mg/g VSS would meet the pathogen requirements for land application of Class A biosolids.
基金the National Basic Research Program (2007CB616909)Startup Foundation of Applied Chemistry of the Key Discipline of Zhejiang University of Technology and Zhejiang Provincial Science and Technology Plan (2006C21107)
文摘Tetra-hydroxymethyl phosphonium chloride （THPC） has been considered as an important chrome-free tanning agent. To understand the THPC tanning mechanism, the structure, charge distribution, activity and tanning ability of each phosphorous compound in THPC tanning system were studied, by ^31p NMR, FT-IR spectroscopy, differential scanning calorimetry （DSC） and computational chemistry method, etc. When pH raised to 6.0, the decomposition of THPC would take place, which results in a production of free formaldehyde, tri-hydroxymethyl phosphonium （TrHP） and tri-hydroxymethyl phosphine oxide （TrHPO）. At pH 9.0, THPC will be converted completely to TrHP and most TrHP is further oxidized into TrHPO. It is possible that, in reaction of phosphorous compounds and collagens, both P-C and C-O bonds would break simultaneously or individually. From molecular charge distribution and bond polar properties, it is deduced that, if P-C bonds break, the activity is in order of TrHPO 〉 THPC 〉 TrHE whereas if C--O bonds break, the order is TrHP 〉 THPC 〉 TrHPO. It is more possible that P--C bonds will break in reaction with collagen, and TrHPO may be more active in the THPC tanning system. The results of tanning and DSC also prove the above conclusion. Furthermore, the fact that the shrinkage temperature of THPC tanned leather was below 70℃ when basified to pH 5.0 or lower suggests that the hydroxymethyl groups of THPC and TrHP are less possible to combine directly with amino groups of collagen.
基金financially supported by the National Key R&D Program of China(No.2021YFA1501600)the National Natural Science Foundation of China(Nos.22175105 and 22031005)。
文摘Well-defined polycarbonate diol was successfully synthesized through a strategy using a combination of organocatalyst and water.Such strategy was less developed in organocatalyzed polymerization and frequently regarded as side reactions.Herein,one-component phosphonium borane Lewis pairs PB1-PB8 were successfully applied in the copolymerization of CO_(2) and cyclohexene oxide(CHO)to generate poly(CHO-alt-CO_(2))carbonate(PCHC).Parameters of linker length and counter anion effects on the catalyst activity were investigated.It was found that Lewis pair PB3 served as a dual initiator and catalyst in the copolymerization of CHO and CO_(2) with or without the presence of water.In contrast,Lewis pair PB8 can serve as a true catalyst for the preparation of well-definedα,ω-hydroxyl PCHC diols.This was achieved by introducing a labile CF3COO group as counter anion through anion exchange reaction while water molecules acted as chain transfer agents.The function of trifluoroacetate group in the polymerization process was investigated in detail and possible mechanism was proposed.Upon changing the amount of water and catalyst loading,PCHC diols with varied molecular weight(1.5 kg/mol to 7.5 kg/mol),low dispersities(D<1.2)and carbonate content(>99%)could be easily obtained.The low molecular weight PCHC diol was used as a bifunctional macroinitiator for the ring-opening polymerization of L-lactide(LLA)to afford ABA triblock copolymer in one-pot synthesis.
文摘Both of quaternary ammonium and quaternary phosphonium salts of bis-hydroxyethyl terephthalate （BHET） were successfully synthesized and characterized by fourier transform infrared spectroscopy （FT-IR）. These two kinds of salts were used to intercalate Na-MMT to yield two kinds of respective organo-modified MMTs. Basal spacing and thermal stability were investigated by using X-ray diffraction （XRD） and thermogravimetric analysis （TGA）, respectively. The experimental results show that, as compared with Na-MMT, basal spacings of both of MMTs modified by the quaternary phosphonium salt of BHET （BHETPP） and the quaternary ammonium salt of BHET （BHEA）, increase from 12.4 A to 19.7/k and 31.3 A, respec-tively. Thermal stability of BHETPP-modified MMT is much better than that of BHEA-modified MMT, i e, T otof BHETPP-modified MMT is around 400℃ while Tcmset of BHEA-modified MMT is near 250℃. Therefore, with en-larged basal spacing and excellent thermal stability, BHETPP-modified MMT is a promising organo-modified MMT which may be used to prepare polyethylene terephthalate/MMT nanocomposite with high thermal and mechanical performance.
基金Projects(20676049, 20871058) supported by the National Natural Science Foundation of China Project(05200555) supported by the Natural Science Foundation of Guangdong Province, China Projects(2007B090400105, 2008A010500005) supported by the Foundation of Enterprise-University-Research Institute Cooperation from Guangdong Province and Ministry of Education of China
文摘Na-montruorillonite （Na-MMT） was exchanged with three quaternary atkylphosphonium salts： decyl tributylphosphonium bromide （DTBPBr）, dodecyl tributylphosphonium bromide （DDTBPBr） and hexadecyl tributylphosphonium bromide （HDTBPBr）, to investigate the effects of phosphonium salts species and relative molecular mass on the characteristics, morphology, thermal stability and long-acting antibacterial property of phosphonium montmorillonites. The resulting modified montmorillonites were characterized by the FTIR, XRD, TEM, and TG/DTG techniques. And minimum inhibitory concentration （MIC） was used to investigate antibacterial activity. The results show that the phosphonium salts are intercalated into Na-MMT, and the basal spacing of P-MMTs is enlarged with the increase of phosphonium salt content or the growth of alkyl chain length. DDTBP-MMT-3 with 19.83% （mass fraction of dodecyl tributylphosphonium salts, displays excellent thermal stability and long-acting antibacterial activity.
文摘ByBimolecular Nucleophilic Substitution, four new types of alkylene triphenyl double quaternary phosphonium salt were synthesized respectively by using triphenylphosphine, 1,3-dibromopropane, 1,6-dibromohexane,1,10-dibromo- decane, 1,12-dibromododecane as raw materials and using DMAC as the solvent, under a certain temperature and reac- tion time. The productivity is 58% - 83%. The molecular structures of the products were characterized by IR, NMR and elemental analysis. The sterilizing effect of 1,6-hexylidene triphenyl double phosphonium bromide(HTDPB) and 1,12- dodecylidene triphenyl double phosphonium bromide(DoTDPB) was evaluated by using extinct dilution method.The experimental result shows that the sterilizing effect of DoTDPB is better than the effect of HTDPB under the same drug concentration and contact time. When the concentration of DoTDPB was 20 mg/L and the contact time was 0.5 h, the sterilizing rate of DoTDPB used to kill saprophytic bacteria (TGB), sulfate-reducing bacteria (SRB) and iron bacteria (IB) was 95.56%, 84% and 99.58% respectively.
基金financially supported by the National Natural Science Foundation of China(Nos.21673077,21473058,and 21273077)
文摘The phosphine-functionalized phosphonium-based ionic liquids(dppm-Q, dppe-Q, dppp-Q and dppb-Q) as the bi-functional ligands enable the efficient one-pot tandem hydroformylationeacetalization. It was found that, in dppm-Q, dppe-Q, dppp-Q and dppb-Q, the incorporated phosphino-fragments were responsible for Rh-catalyzed hydroformylation and the phosphoniums were in charge of the subsequent acetalization as the Lewis acid catalysts. Moreover, the diphosphonium-based ionic liquid of dppb-DQ could be applied as a co-solvent to immobilize the Rh/dppb-Q catalytic system with the advantages of the improved catalytic performance, the available catalyst recyclability, and the wide generality for the substrates.
基金We thank the National Natural Science Foundation of China for financial support of the project 29972036 and the Foundation of Educational Ministry for the Scholars Returning from Abroad. .
文摘Phosphonium or arsonium salt 1 can undergo the tandem reaction of deprotonation -oxidation-Wittig reaction with alcohol 2 in the presence of sodium hydroxide and manganese dioxide, which affords a general simplified method for the stereoselective synthesis of (E)- a, b-unsaturated esters 3.
基金supported by the National Natural Science Foundation of China(Nos.51778230,22376065)Program of Shanghai Outstanding Technology Leaders(No.20XD1433900)+1 种基金the Science and Technology Commission of Shanghai Municipality(No.22ZR1418600)Shanghai Municipal Science and Technology(No.20DZ2250400)。
文摘Microbial contamination in water has emerged as a critical concern and thus developing biocide materials for controlling microbial contamination is crucial.Removing all pathogenic bacteria in water is difficult when using traditional water treatment technologies.Moreover,these bacteria can easily reproduce during pipeline distribution.In this work,a facile and effective chitosan derivative biocide denoted as PCC was developed by grafting with quaternary phosphonium salt(QPS).PCC became positively charged with a wide range of p H and demonstrated antibacterial activity up to 95%and 100%against Escherichia coli and Staphylococcus aureus as model pathogens,respectively.The grafting of QPS may disrupt the cell membrane and lead to bacterial inactivation,as demonstrated by the scanning electron microscopy image and the concentration of intracellular substance leakage.MTT assay results indicate that PCC achieved good biocompatibility with negligible in vitro cytotoxicity.These findings introduce a promising approach for bacterial decontamination due to its low cytotoxicity and high biocidal activity.
基金financially supported by the National Natural Science Foundation of China (Nos. 21972112 and 22225104)China Postdoctoral Science Foundation (Nos. 2022TQ0115 and 2022M711297)。
文摘Chemoselective,living/controlled polymerizations of allyl methacrylate(AMA) and vinyl methacrylate(VMA) with/without methyl methacrylate(MMA) by using the phosphonium ylide/organoaluminum based Lewis pairs(LPs) have been realized.The P-ylide-2/AIMe(BHT)_(2)(Pylide-2=Ph_(3)P=CHMe and BHT=2,6-iBu_(2)-4-MeC_(6)H_(2)O) was demonstrated to be superior by which homopolymers PAMAs(M_(n)=27.6-111.5kg/mol and ■=1.14-1.25) and PVMAs(M_(n)=28.4-78.4 kg/mol and ■=1.12-1.18) and block copolymers PMMA-b-PAMA,PAMA-b-PVMA,PAMA-bPMMA,PMMA-b-PAMA-b-PMMA,PAMA-b-PMMA-b-PAMA,and PAMA-b-PVMA-b-PAMA were synthesized.In the polymerizations,all of the monomers were reacted by the conjugated ester vinyl groups leaving intactly the nonconjugated acryloxy groups.The pendant acryloxy groups attached to the main chain enable further to post-functionalization by the AIBN-induced radical "thiol-ene" reaction using PhCH_(2)SH.The thiolether side group-containing polymers PAMA-SCH_(2)Ph and PAMA-SCH_(2)Ph-b-PMMA-b-PAMA-SCH_(2)Ph were thus prepared.
基金supported by the National Natural Science Foundation of China(No.22001248)the Fundamental Research Funds for the Central Universities and University of Chinese Academy of Sciences.
文摘A charge transfer complex(CTC)-enabled photoreduction of ether phosphonium salts for the generation of oxyalkyl radicals was described.The photoreduction provides a convenient method to achieve selective oxyalkylation of enamides with broad substrate scope.The method features operational simplicity,mild and inherent green conditions.
基金supported by the Public Welfare Specialized Research Fund,Ministry of Agriculture ( 200803013)the Director Fund of Pearl River Fisheries Research Institute( 2007-G-6)
文摘[ Objective] To understand the toxicity and sterilization effects of the tetrakis hydroxmethyl phosphonium sulfate （THPS） as a novel quatemary phosphonium biocide. [ Method] Under hydrostatic conditions, the acute toxicity and bactericidal property of THPS on the Fiexibacter coiumnaris （ F. columnaris） were observed in Japanese eel. The semi-lethal concentration （LCso）, safe concentration （Sc）, minimum inhibitory concentration （MIC）, minimum bactericidal concentration （MBC） and the sterilization rate of THPS were calculated, respectively. [ Result ] The LCso of THPS at 24, 48 and 96 h were 11.9, 9.9 and 9.1 mg/L, respectively. The Sc of THPS at 24 h was 2.1 mg/L; the MIC and MBC of THPS to the F. columnaris were 0.36 and 0.72 mg/L; and the sterilization rate was 100% at a concentration of 0.7 mg/L at 12 h. The sterilization rate of THPS had no great change with pH values varying from 5.5 to 9.5. [ Condusion] The THPS is a novel, safe and effective biocide for prevention and treatment of bacterial diseases of Japanese eel.
文摘Synthesis of terpolymers consisting of two electron-donating monomers, viz. styrene and vinyl acetate with one electron-accepting monomer, i.e. acrylonitrile, initiated by p-nitrobenzyl triphenyl phosphonim ylide in dioxane as diluent at 65°C for 150 min has been studied. The kinetic expression is Rpα[I]0.8[Sty] 1.2[VA] 1.4 [AN]1.2. The terpolymer composition was determined by the Kelen-Tüdos method. The values of reactivity ratios using r1 (Sty + VA) = 0.1 and r2 (AN) = 0.005. The overall activation energy is 46 kJ●mol●L–1. The formation of terpolymer is confirmed by the FTIR spectra showing bands at 3030 cm–1, 1598 cm–1, and 2362 cm–1, confirming the presence of phenyl, acetoxy and nitrile group respectively. The terpolymer has been characterized by 1H-Nuclear Magnetic Resonance, 13C-Nuclear Magnetic Resonance. The Differential Scanning Calorimetric curve shows the Tg of the polymer as 149.5°C. A scanning electron microscope confirms the polymer to be phosphorus free. Electron.Spin.Resonance spectra confirms phenyl radical responsible for initiation.
文摘A study of the quenching of pyrene fluorescence by a series of alkyltriphenylphosphonium bromides indi- cated the coiling conformation of ionic surfactant in aqueous solution.Formation of pyrene excimer in cetyltriph- enylphosphonium solution strengthened the conclusion.
文摘Quaternary phosphonium salts （QPS） with reactive groups used as antibacterial agents are promising which could be covalently linked to inert polymer surfaces by in situ polymerization. In this work, two kinds of quaternary phosphonium salts with hydroxyl groups were synthesized successfully. Characterization of these two quaternary phosphonium salts was performed by the Fourier transform infrared spectroscopy （FT-IR） and nuclear magnetic resonance （NMR） spectrometry. The thermal stability and antibacterial activity of antibacterial agents were also investigated by using thermo-gravimetric analysis, differential scanning calorimetry （TG-DSC） and agar diffusion method. The test results showed that these two QPS exhibited good thermal stability and excellent antibacterial activity against both bacteria： Staphylococcus aureus and Escherichia coll.
文摘In this study was to investigate, by phase-transfer catalysis, the activity of single and mixed ammonium and phosphonium salts grafted on a 揼el-type?styrene-7% divinylbenzene copolymer in the oxidation of benzyl alcohol with hydrogen peroxide. A wide variety of catalysts with different quaternary groups and different quaternary chain length substituents were examined. The activity of single 搊nium?salts increases as a consequence of the association of ammonium and phosphonium salts grafted on the same polymeric support. The activity of polymer-supported ammonium and phosphonium salts increases with the number of carbon atoms contained in the alkyl radicals of the onium and of the functionalization degree with phosphonium groups.
文摘A systematic study on the synthesis and antibacterial activity of the quaternary "onium" salts grafted on an insoluble "gel-type" styrene-7% divinylbenzene copolymer by polymer-analogous reactions is showed. Antibacterial activity of quaternary ammonium and/or phosphonium salts grafted on polymer-supports has been studied against Staphylococcus aureus and Escherichia coli. A wide variety of "onium" salts bound to macromolecular supports with different quaternary groups and different quaternary chain length substituents were examined. The antibacterial activity of mixed "onium" salts increases as a consequence of the association of ammonium and phosphonium salts grafted on the same polymeric support.
基金supported by the National Natural Science Foundation of China(U23A20594 and 22375066)the Guangdong Basic and Applied Basic Research Foundation(2023B1515040003)the Fundamental Research Funds for the Central Universities(2024ZYGXZR004).
文摘Phosphorus-containing functional materials have diverse applications in optoelectronics and bioscience owing to their unique properties.However,polycyclicπ-conjugated phosphonium salts have been rarely explored due to their complex synthesis.In this work,a facile and efficient method for constructing polycyclicπ-conjugated phosphonium salts(TBPIMe derivatives)is proposed,based on the photocyclization of phosphindolium salts(TPPIMe derivatives).Systematic experimental and theoretical investigations reveal the changed photophysical and photochemical properties when TPPIMe derivatives are converted to TBPIMe derivatives.Notably,the novel polycyclicπ-conjugated phosphonium salt p-MOTBPIMe exhibits improved reactive oxygen species generation ability and much stronger specific affinity toward DNA than phosphindolium salts p-MOTPPIMe.Moreover,in vitro experiments demonstrate that p-MOTPPIMe can also be efficiently converted into p-MOTBPIMe under 405 nm laser irradiation in living cells,accompanied by the migration from cytoplasm to nucleus to enhance the photodynamic effect.Additionally,p-MOTBPIMe shows superior antibacterial activity against not only Gram-positive drug-resistant bacteria but also fungi,by leveraging both dark and light cytotoxicity.This work opens up a new chemical toolkit for novel polycyclicπ-conjugated phosphonium salts,which are promising for developing advanced theranostic agents with satisfactory accuracy and efficacy.
