In this paper,a series of optically active MeO-BIPHEP-type ligands,（S）-6,6′-dimethoxy-2,2’-bis（di-p-alkoxyphenylphosphine）- 1,1′-biphenyl were synthesized and used to prepare the ruthenium complex.The effects o...In this paper,a series of optically active MeO-BIPHEP-type ligands,（S）-6,6′-dimethoxy-2,2’-bis（di-p-alkoxyphenylphosphine）- 1,1′-biphenyl were synthesized and used to prepare the ruthenium complex.The effects of para-substituted were observed,the results showed that the ruthenium catalysts[diphosphine RuCl;diamine]containing both t-Bu and i-Pr substitutions have better activities and enantioselectivities than the non-substituted ruthenium catalysts in the asymmetric hydrogenation of acetophenone.展开更多
Lead(Pb)^(0) and iodine(I)^(0) point defects generated during perovskite solar cell(PSC)fabrication and photoconversion form deep band energy levels as the carriers’recombination centers.These defects not only deteri...Lead(Pb)^(0) and iodine(I)^(0) point defects generated during perovskite solar cell(PSC)fabrication and photoconversion form deep band energy levels as the carriers’recombination centers.These defects not only deteriorate device efficiency,but also facilitate chemical degradation with ion migration,resulting in restricted device lifetime.Herein,we present a novel type of phosphines as the point defects stabilizer for hybrid perovskite solar cells with enhanced performances.Three phosphines with varied side groups of tributyl,trioctyl and triphenyl are exampled as the dopants in perovskite films.The group dependent redox properties were observed in the perovskite film,dependent on their molecular weights and steric hinderances of phosphines.The partially oxidized tributyl phosphine(TBUP)with additional tributyl phosphine oxides(TBPO)is efficient in reduction of lead(Pb)^(0) and iodine(I)^(0) concentrations during the device fabrication and operation.The device with TBUP-TBPO pair showed enhanced power conversion efficiency(PCE)to 20.48% and maintain 91.7% of their initial PCEs after 500 h at 65℃ thermal annealing.Thus,this work presents an efficient route of utilize the phosphine species to reduce point defects in the perovskite film,which promoting further development of novel phosphorous additives with defects stabilization,interface passivation and encapsulation for low-cost solution processed PSCs.展开更多
A divergent intramolecular reaction of phosphine tethered alkyne in protic solvent was developed.This provided a novel and simple access to a large variety of(Z)-alkenylphosphine oxides and phospholane oxides.Our prel...A divergent intramolecular reaction of phosphine tethered alkyne in protic solvent was developed.This provided a novel and simple access to a large variety of(Z)-alkenylphosphine oxides and phospholane oxides.Our preliminary studies suggested that these divergent reactions are closely related to the reaction condition and molecular structure.A possible mechanism of C-P bond cleavage of a pentacoordinated hydroxyphosphorane intermediate was proposed.展开更多
The new type of water-soluble phosphine with the involvement of the trivalent rare earth ion, TPPTS?Ln (Ln=Eu, Dy, Er, Tm, Yb, Lu; and TPPTS=tris (m-sulfonatophenyl) phosphine), were synthesized from the precursor TPP...The new type of water-soluble phosphine with the involvement of the trivalent rare earth ion, TPPTS?Ln (Ln=Eu, Dy, Er, Tm, Yb, Lu; and TPPTS=tris (m-sulfonatophenyl) phosphine), were synthesized from the precursor TPPTS?Na3 and oxides of rare earth. The chemical composition of TPPTS?Ln was determined by elemental analysis and ICP-AES. IR, Raman showed that the sulfonate group in the complexes was a tridentate ligand.31P NMR, TG-DTA, molar conductivity and the fluorescence of these complexes were also recorded and discussed.展开更多
Methyl 3-deoxy-3-(diphenylphosphino)-4,6-O-benzylidene-alpha-D-altropyranoside (1) and methyl 2-deoxy-2-(diphenylphosphino)-4,6-O-benzylidene-alpha-D-altropyranoside (2) were prepared from methyl 2,3-anhydro-4,6-O-ben...Methyl 3-deoxy-3-(diphenylphosphino)-4,6-O-benzylidene-alpha-D-altropyranoside (1) and methyl 2-deoxy-2-(diphenylphosphino)-4,6-O-benzylidene-alpha-D-altropyranoside (2) were prepared from methyl 2,3-anhydro-4,6-O-benzylidene-O-D-mannopyranoside and methyl 2,3-anhydro-4,6-O-benzylidene-alpha-D-allopyranoside, respectively, via regioselective and stereospecific ring-opening reactions in high yields. Compounds 1 and 2 were oxidized to give the corresponding phosphine oxides (3 and 4).展开更多
Ligand-stabilized metal nanoclusters with atomic precision have garnered significant attention for applications in catalysis,biomedicine,and nanoelectronics due to their tunable structures and unique physicochemical p...Ligand-stabilized metal nanoclusters with atomic precision have garnered significant attention for applications in catalysis,biomedicine,and nanoelectronics due to their tunable structures and unique physicochemical properties[1-3].While transition metals such as Au,Ag,Pt,and Pd dominate the core composition,surface ligands are predominantly limited to phosphines,thiols,alkynes,and carbenes.Among these,N-heterocyclic carbenes(NHCs)have emerged as a superior ligand class due to their dual capacity for strongσ-donation andπ-back bonding,which stabilizes diverse metal oxidation states and enhances metal-ligand interactions.Notably,NHC-protected clusters exhibit exceptional thermal stability attributed to CH-π/π-πinteractions and enlarged HOMO-LUMO gaps compared to thiol or phosphine analogues.Despite progress,synthetic limitations persist due to NHCs'sensitivity under harsh conditions.Current methods rely on direct reduction of metal-carbene precursors or ligand exchange reactions,with heterogeneous NHC-capped systems remaining unexplored.展开更多
Organoboron compounds have become important intermediates for the construction of new compounds in synthetic chemistry and pharmaceutical chemistry,and it has been found that pinacol biborate(B_(2)pin_(2))as the boron...Organoboron compounds have become important intermediates for the construction of new compounds in synthetic chemistry and pharmaceutical chemistry,and it has been found that pinacol biborate(B_(2)pin_(2))as the boron source and Cu^(Ⅱ) organophosphorus complex(L)as the catalyst can effectively realize the hydrogen-reduced borylation products and dehydrohydrated borylation products of aryl olefins.The reaction regioselectivity involvingβ-C positions of aryl olefins can be controlled by regulating the ligand and additive types.The formation mechanism of the product is conducted at LCu^(Ⅰ)Bpin formed from Cu^(Ⅱ),L and B_(2)pin_(2).Subsequently the substrate aryl olefins undergo addition reaction to form the active intermediate PhCH(LCu^(Ⅰ))CH_(2)Bpin.Followed by the metathesis of the active intermediate with water to form hydrogen reduction products,the same active intermediate can be oxidized with 2,2,6,6-tetramethylpiperidoxyl(TEMPO)to form trans dehydrogenation products.展开更多
The chemo-,regio-,and enantio-controlled synthesis of P-chiral phosphines in a general and efficient manner remains a significant synthetic challenge.In this study,a Pd-catalyzed hydrofunctionalization is developed fo...The chemo-,regio-,and enantio-controlled synthesis of P-chiral phosphines in a general and efficient manner remains a significant synthetic challenge.In this study,a Pd-catalyzed hydrofunctionalization is developed for the highly selective synthesis of P-stereogenic alkenylphosphinates and alkenylphosphine oxides via conjugate addition of enynes.Notably,this methodology is suitable for both phosphine oxide and phosphinate nucleophiles,providing a versatile approach for the construction of diverse P-chiral organophosphosphorus compound.展开更多
Polycyclic compounds are widely found in natural products and drug molecules with important biological activities,which attracted the attention of many chemists.Phosphine-catalyzed nucleophilic addition is one of the ...Polycyclic compounds are widely found in natural products and drug molecules with important biological activities,which attracted the attention of many chemists.Phosphine-catalyzed nucleophilic addition is one of the most powerful tools for the construction of various cyclic compounds with the advantages of atom economy,mild reaction conditions and simplicity of operation.Allenolates,Morita−Baylis−Hillman(MBH)alcohols and their derivatives(MBHADs),electron-deficient olefins and alkynes are very efficient substrates in phosphine mediated annulations,which formed many phosphonium species such asβ-phosphonium enolates,β-phosphonium dienolates and vinyl phosphonium ylides as intermediates.This review describes the reactivities of these phosphonium zwitterions and summarizes the synthesis of polycycle compounds through phosphine-mediated intramolecular and intermolecular sequential annulations.Thus,a systematic summary of the research process based on the phosphine-mediated sequential annulations of allenolates,MBH alcohols and MBHADs,electron-deficient olefins and alkynes are presented in Chapters 2-6,respectively.展开更多
A cobalt pincer complex bearing both P and C-stereogenic centers has been designed and synthesized,allowing for the development of the first cobalt-catalyzed asymmetric hydrogenation of quinoxalines under relatively m...A cobalt pincer complex bearing both P and C-stereogenic centers has been designed and synthesized,allowing for the development of the first cobalt-catalyzed asymmetric hydrogenation of quinoxalines under relatively mild conditions.Valuable chiral 1,2,3,4-tetrahydroquinoxalines could be obtained with high yields and excellent enantioselectivities(35 examples,up to>99%ee).展开更多
The oxygen evolution reaction(OER)is a key process in water splitting for hydrogen production,yet its sluggish kinetics pose significant challenges for catalyst development.In this work,we present the first systematic...The oxygen evolution reaction(OER)is a key process in water splitting for hydrogen production,yet its sluggish kinetics pose significant challenges for catalyst development.In this work,we present the first systematic study on isostructural 2D coordination polymers(CPs)based on 1,10-ferrocenediyl-bis(H-phosphinic)acid,with cobalt,manganese,and cadmium metals as electrocatalysts for OER.These polymers were synthesized via a facile solution reaction,yielding crystalline materials with excellent structural integrity.The electrocatalytic performance of CPs composites,prepared with carbon and phosphonium ionic liquid,was evaluated in 0.1 M KOH using a three-electrode system.Notably,the Co-and Cd-based CPs demonstrated exceptional OER activity,achieving an overpotential as low as 236–255 mV at 10 mA cm^(-2),surpassing those of many previously reported CP-based OER catalysts.Furthermore,these materials exhibited high stability over prolonged electrolysis,maintaining their activity without significant degradation.This work not only introduces a new class of ferrocenyl phosphinatebased CPs as highly active and durable OER catalysts but also provides valuable insights into their structureactivity relationships,paving the way for future advancements in electrocatalysis.展开更多
Rh/SiO2 catalysts with tethered-phosphines with different alkyl spacer lengths have been prepared,tested and characterized.Lengthening the alkyl spacer of the tethered-phosphine improved the flexibility of tethered-ph...Rh/SiO2 catalysts with tethered-phosphines with different alkyl spacer lengths have been prepared,tested and characterized.Lengthening the alkyl spacer of the tethered-phosphine improved the flexibility of tethered-phospine,promoted the formation of active species and enhanced the activity of hydroformylation over other tethered-phosphine modified Rh/SiO2 catalysts.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
Nucleophilic chiral phosphine catalysis has been prosperous in asymmetric synthesis over the past two decades. Various tunable chiral phosphines display excellent activity and selectivity in asymmetric transformations...Nucleophilic chiral phosphine catalysis has been prosperous in asymmetric synthesis over the past two decades. Various tunable chiral phosphines display excellent activity and selectivity in asymmetric transformations including acycloaddition reactions and cycloaddition reactions. Enantiomerically enriched cyclic compounds are ubiquitous in natural products and drug molecules. These phosphinecatalyzed reactions provide effective and extensive strategies for the synthesis of a series of complex cyclic compounds as well as the synthesis of chiral compounds which could be easily transformed to carbocycles and heterocycles. This minireview summarizes recent developments in this area and highlights meaningful breakthroughs.展开更多
The （COCl）2/Hantzsch ester is found to be an effective system for the metal-free reduction of tertiary phosphine oxides. The reaction proceeds under mild conditions, and is applicable to triarylphosphine oxides and ...The （COCl）2/Hantzsch ester is found to be an effective system for the metal-free reduction of tertiary phosphine oxides. The reaction proceeds under mild conditions, and is applicable to triarylphosphine oxides and alkyldiarylphosphine oxides to produce the corresponding tertiary phosphines in good to excellent yields. This new finding provides a practical, convenient and metal-free method for the reduction of tertiary phosphine oxides to tertiary phosphines, and shows potential application in organic synthesis.展开更多
The neutral palladium（Ⅱ） complex bis-[1-（5＇-diphenylphosphinothiazol-2＇-yl）-imidazolyl]dichloropalladium（Ⅱ）（1A） ligated by thiazolylimidazolyl-based phosphine（L1） in which thiazolylimidazolyl acted as an...The neutral palladium（Ⅱ） complex bis-[1-（5＇-diphenylphosphinothiazol-2＇-yl）-imidazolyl]dichloropalladium（Ⅱ）（1A） ligated by thiazolylimidazolyl-based phosphine（L1） in which thiazolylimidazolyl acted as an S- and N-donor provider with weak coordinating nature,and the ionic complex bis-[1-（5＇-diphenylphosphinothiazol-2＇-yl）-3-methylimidazolium]dichloropalladium（Ⅱ） trifluoromethanesulfonate（2A） ligated by thiazolylimidazolium-based phosphine（L2） after quaternization of L1 using methyl trifluoromethanesulphonate were synthesized.It was found that the introduced positive charges and strong electron-withdrawing effect in 2A not only led to changes in the configuration and structural stability of the complex,but also lowered its catalytic performance in carbonylative Sonogashira reactions.These effects reveal the important role of the N-donor in 1A.In addition,as an ionic palladium complex,2A combined with the room-temperature ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate could be recycled eight times as the catalyst in carbonylative Sonogashira reactions without detectable metal leaching.展开更多
[Objective] This study aimed to investigate the killing effect of mixed fumi- gation of phosphine and carbon dioxide on eggs of Lasioderma serricorne F. [Method] The outside-storage phosphine generator was placed in a...[Objective] This study aimed to investigate the killing effect of mixed fumi- gation of phosphine and carbon dioxide on eggs of Lasioderma serricorne F. [Method] The outside-storage phosphine generator was placed in a tabernacled smoke box, and the mortality rates of L. serricome F. eggs in the smoke box under conditions of different aluminium phosphide usage amount and different fumigation time were studied. In addition, the times needed by tabernacle and smoke box cen- ter to reach the phosphine concentration peak were recorded. [Result] The optimum conditions for killing the eggs of L. serricorne were as follows： temperature of （27± 2） ℃, relatively humidity of （45±5）%, aluminium phosphide usage amount of 1.5 g/m3 and effective exposure time of 96 h. The killing effect of mixed fumigation of phos- phine and carbon dioxide was increased with the extension of fumigation time. The increased usage amount of aluminium phosphide showed no significant effect on killing effect. The tabernacle space and smoke box center all required relatively short time to reach the phosphine concentration peak. If the tabernacle had a good airtightness, the overall fumigation time could be shortened. [Conclusion] The fumi- gation method is reliable, and it can be used for the control of L. serricorne F. in tobacco storage.展开更多
To minimize the loading level of the char-forming phosphorus based flame retardants in the poly（lactic acid） （PLA） with reduced flammability, we have developed the flame-retarded PLA nanocomposites by melt blendin...To minimize the loading level of the char-forming phosphorus based flame retardants in the poly（lactic acid） （PLA） with reduced flammability, we have developed the flame-retarded PLA nanocomposites by melt blending method incorporating organically modified montmorillonite （OMMT） and aluminium diethylphosphinate （A1Pi） additives. The influence of A1Pi and OMMT on flame retardancy and thermal stability of PLA was thoroughly investigated by means of the limiting oxygen index （LOI）, UL94 test, cone calorimeter, X-ray diffraction （XRD）, thermogravimetric analysis and scanning electronic microscopy （SEM）. The experimental results show that the PLA/A1Pi/OMMT system has excellent fire retardancy. The LOI value increases from 19% for pristine PLA to 28% for the flame-retarded PLA. Cone calorimeter analysis of the PLA/A1Pi/OMMT exhibits a reduction in the peak heat release rate values by 26.2%. Thermogravimetric analysis and SEM of cone calorimeter residues indicate that OMMT significantly enhances the thermal stability, promotes char-forming and suppresses the melt dripping. The research of this study implies that the combining of the flame retardant and organoclay results in a synergistic effect. In addition, the flame-retarded PLA nanocomposite also exhibits notable increase in the impact strength and the elongation at break.展开更多
[Objective] This study aimed to investigate the effects of phosphine on germination and physiological characteristics of rice seeds. [Method] Simulation envi- ronments were conducted to study the effects of high-level...[Objective] This study aimed to investigate the effects of phosphine on germination and physiological characteristics of rice seeds. [Method] Simulation envi- ronments were conducted to study the effects of high-level phosphine on germination status and physiological characteristics of rice seeds and explore the early environ- mental and ecological effects of phosphine on rice growth in phosphorus cycle of paddy field. [Result] Experimental results showed that the increase of phosphine con- centration in the environment resulted in the decrease of germination rate and ger- mination potential by 11.11% and 19.71%, respectively. In addition, the activities of catalase （CAT） and peroxidase （POD） were reduced to 94.35% and 92.61%, respec- tively; the content of malondialdehyde （MDA） was maximally increased by 29.11%, indicating that both germination potential and growth condition of rice seeds were in- hibited under conditions of high-level phosphine. [Conclusion] This study provided theoretical basis for investigating the effects of phosphine on germination of rice seeds under natural environment.展开更多
We prepared a kind of metal oxide-modified walnut-shell activated carbon(MWAC) by KOH chemical activation method and used for PH_3 adsorption removal. Meanwhile, the PH_3 adsorption equilibrium was investigated experi...We prepared a kind of metal oxide-modified walnut-shell activated carbon(MWAC) by KOH chemical activation method and used for PH_3 adsorption removal. Meanwhile, the PH_3 adsorption equilibrium was investigated experimentally and fitted by the Toth equation, and the isosteric heat of PH_3 adsorption was calculated by the Clausius-Clapeyron Equation. The exhausted MWAC was regenerated by water washing and air drying. Moreover, the properties of five different samples were characterized by N_2 adsorption isotherm, SEM/EDS, XPS, and FTIR. The results showed that the maximum PH_3 equilibrium adsorption capacity was 595.56 mg/g. The MWAC had an energetically heterogeneous surface due to values of isosteric heat of adsorption ranging from 43 to 90 kJ/mol. The regeneration method provided an effective way for both adsorption species recycling and exhausted carbon regeneration. The high removal efficiency and big equilibrium adsorption capacity for PH_3 adsorption on the MWAC were related to its large surface area and high oxidation activity in PH_3 adsorption-oxidation to H_3 PO_4 and P_2 O_5. Furthermore, a possible PH_3 adsorption mechanism was proposed.展开更多
基金the NSFC(No.20272037),the Doctor's Foundation of Education Ministry of China(No.20030610022)Foundation of Xihua University(No.R0723315) and(No.07ZA109) for the financial support of this work.
文摘In this paper,a series of optically active MeO-BIPHEP-type ligands,（S）-6,6′-dimethoxy-2,2’-bis（di-p-alkoxyphenylphosphine）- 1,1′-biphenyl were synthesized and used to prepare the ruthenium complex.The effects of para-substituted were observed,the results showed that the ruthenium catalysts[diphosphine RuCl;diamine]containing both t-Bu and i-Pr substitutions have better activities and enantioselectivities than the non-substituted ruthenium catalysts in the asymmetric hydrogenation of acetophenone.
基金supported financially by the National Key Research and Development Plan,China(2017YFE0131900)the National Science Foundation of China(NSFC 51672202,21875178)+1 种基金the Technological Innovation Key Project of Hubei Province(2018AAA048)the support the“Chutian Scholar Program”of Hubei Province,China。
文摘Lead(Pb)^(0) and iodine(I)^(0) point defects generated during perovskite solar cell(PSC)fabrication and photoconversion form deep band energy levels as the carriers’recombination centers.These defects not only deteriorate device efficiency,but also facilitate chemical degradation with ion migration,resulting in restricted device lifetime.Herein,we present a novel type of phosphines as the point defects stabilizer for hybrid perovskite solar cells with enhanced performances.Three phosphines with varied side groups of tributyl,trioctyl and triphenyl are exampled as the dopants in perovskite films.The group dependent redox properties were observed in the perovskite film,dependent on their molecular weights and steric hinderances of phosphines.The partially oxidized tributyl phosphine(TBUP)with additional tributyl phosphine oxides(TBPO)is efficient in reduction of lead(Pb)^(0) and iodine(I)^(0) concentrations during the device fabrication and operation.The device with TBUP-TBPO pair showed enhanced power conversion efficiency(PCE)to 20.48% and maintain 91.7% of their initial PCEs after 500 h at 65℃ thermal annealing.Thus,this work presents an efficient route of utilize the phosphine species to reduce point defects in the perovskite film,which promoting further development of novel phosphorous additives with defects stabilization,interface passivation and encapsulation for low-cost solution processed PSCs.
基金National Natural Science Foundation of China(Nos.21672193,21272218)Henan Province postdoctoral research start-up projectZhengzhou University of China for financial support of this research。
文摘A divergent intramolecular reaction of phosphine tethered alkyne in protic solvent was developed.This provided a novel and simple access to a large variety of(Z)-alkenylphosphine oxides and phospholane oxides.Our preliminary studies suggested that these divergent reactions are closely related to the reaction condition and molecular structure.A possible mechanism of C-P bond cleavage of a pentacoordinated hydroxyphosphorane intermediate was proposed.
文摘The new type of water-soluble phosphine with the involvement of the trivalent rare earth ion, TPPTS?Ln (Ln=Eu, Dy, Er, Tm, Yb, Lu; and TPPTS=tris (m-sulfonatophenyl) phosphine), were synthesized from the precursor TPPTS?Na3 and oxides of rare earth. The chemical composition of TPPTS?Ln was determined by elemental analysis and ICP-AES. IR, Raman showed that the sulfonate group in the complexes was a tridentate ligand.31P NMR, TG-DTA, molar conductivity and the fluorescence of these complexes were also recorded and discussed.
基金Project supported by the State Key Project for Fundamental Research and the National Natural Science Foundation of China.
文摘Methyl 3-deoxy-3-(diphenylphosphino)-4,6-O-benzylidene-alpha-D-altropyranoside (1) and methyl 2-deoxy-2-(diphenylphosphino)-4,6-O-benzylidene-alpha-D-altropyranoside (2) were prepared from methyl 2,3-anhydro-4,6-O-benzylidene-O-D-mannopyranoside and methyl 2,3-anhydro-4,6-O-benzylidene-alpha-D-allopyranoside, respectively, via regioselective and stereospecific ring-opening reactions in high yields. Compounds 1 and 2 were oxidized to give the corresponding phosphine oxides (3 and 4).
文摘Ligand-stabilized metal nanoclusters with atomic precision have garnered significant attention for applications in catalysis,biomedicine,and nanoelectronics due to their tunable structures and unique physicochemical properties[1-3].While transition metals such as Au,Ag,Pt,and Pd dominate the core composition,surface ligands are predominantly limited to phosphines,thiols,alkynes,and carbenes.Among these,N-heterocyclic carbenes(NHCs)have emerged as a superior ligand class due to their dual capacity for strongσ-donation andπ-back bonding,which stabilizes diverse metal oxidation states and enhances metal-ligand interactions.Notably,NHC-protected clusters exhibit exceptional thermal stability attributed to CH-π/π-πinteractions and enlarged HOMO-LUMO gaps compared to thiol or phosphine analogues.Despite progress,synthetic limitations persist due to NHCs'sensitivity under harsh conditions.Current methods rely on direct reduction of metal-carbene precursors or ligand exchange reactions,with heterogeneous NHC-capped systems remaining unexplored.
文摘Organoboron compounds have become important intermediates for the construction of new compounds in synthetic chemistry and pharmaceutical chemistry,and it has been found that pinacol biborate(B_(2)pin_(2))as the boron source and Cu^(Ⅱ) organophosphorus complex(L)as the catalyst can effectively realize the hydrogen-reduced borylation products and dehydrohydrated borylation products of aryl olefins.The reaction regioselectivity involvingβ-C positions of aryl olefins can be controlled by regulating the ligand and additive types.The formation mechanism of the product is conducted at LCu^(Ⅰ)Bpin formed from Cu^(Ⅱ),L and B_(2)pin_(2).Subsequently the substrate aryl olefins undergo addition reaction to form the active intermediate PhCH(LCu^(Ⅰ))CH_(2)Bpin.Followed by the metathesis of the active intermediate with water to form hydrogen reduction products,the same active intermediate can be oxidized with 2,2,6,6-tetramethylpiperidoxyl(TEMPO)to form trans dehydrogenation products.
基金the National Natural Science Foundation of China(NSFC,No.22271241),Yunnan Key Laboratory of Chiral Functional Substance Research and Application(No.202402AN360010)Research Grants Council of Hong Kong(GRF,No.12303422)HKBU KRPS grant for financial support.
文摘The chemo-,regio-,and enantio-controlled synthesis of P-chiral phosphines in a general and efficient manner remains a significant synthetic challenge.In this study,a Pd-catalyzed hydrofunctionalization is developed for the highly selective synthesis of P-stereogenic alkenylphosphinates and alkenylphosphine oxides via conjugate addition of enynes.Notably,this methodology is suitable for both phosphine oxide and phosphinate nucleophiles,providing a versatile approach for the construction of diverse P-chiral organophosphosphorus compound.
基金the National Natural Science Foundation of China(Nos.22171147 and 21871148)for the financial support。
文摘Polycyclic compounds are widely found in natural products and drug molecules with important biological activities,which attracted the attention of many chemists.Phosphine-catalyzed nucleophilic addition is one of the most powerful tools for the construction of various cyclic compounds with the advantages of atom economy,mild reaction conditions and simplicity of operation.Allenolates,Morita−Baylis−Hillman(MBH)alcohols and their derivatives(MBHADs),electron-deficient olefins and alkynes are very efficient substrates in phosphine mediated annulations,which formed many phosphonium species such asβ-phosphonium enolates,β-phosphonium dienolates and vinyl phosphonium ylides as intermediates.This review describes the reactivities of these phosphonium zwitterions and summarizes the synthesis of polycycle compounds through phosphine-mediated intramolecular and intermolecular sequential annulations.Thus,a systematic summary of the research process based on the phosphine-mediated sequential annulations of allenolates,MBH alcohols and MBHADs,electron-deficient olefins and alkynes are presented in Chapters 2-6,respectively.
基金the financial support of the National Natural Science Foundation of China(No.21672133)the Opening Foundation of Key Laboratory of Applied Surface and Colloid Chemistry,Ministry of Education(No.GK202205011)the Fundamental Research Funds for the Central Universities(Nos.GK202307007 and GK202002003)。
文摘A cobalt pincer complex bearing both P and C-stereogenic centers has been designed and synthesized,allowing for the development of the first cobalt-catalyzed asymmetric hydrogenation of quinoxalines under relatively mild conditions.Valuable chiral 1,2,3,4-tetrahydroquinoxalines could be obtained with high yields and excellent enantioselectivities(35 examples,up to>99%ee).
文摘The oxygen evolution reaction(OER)is a key process in water splitting for hydrogen production,yet its sluggish kinetics pose significant challenges for catalyst development.In this work,we present the first systematic study on isostructural 2D coordination polymers(CPs)based on 1,10-ferrocenediyl-bis(H-phosphinic)acid,with cobalt,manganese,and cadmium metals as electrocatalysts for OER.These polymers were synthesized via a facile solution reaction,yielding crystalline materials with excellent structural integrity.The electrocatalytic performance of CPs composites,prepared with carbon and phosphonium ionic liquid,was evaluated in 0.1 M KOH using a three-electrode system.Notably,the Co-and Cd-based CPs demonstrated exceptional OER activity,achieving an overpotential as low as 236–255 mV at 10 mA cm^(-2),surpassing those of many previously reported CP-based OER catalysts.Furthermore,these materials exhibited high stability over prolonged electrolysis,maintaining their activity without significant degradation.This work not only introduces a new class of ferrocenyl phosphinatebased CPs as highly active and durable OER catalysts but also provides valuable insights into their structureactivity relationships,paving the way for future advancements in electrocatalysis.
基金financially supported by the National Natural Science Foundation of China(21273227,20903090)~~
文摘Rh/SiO2 catalysts with tethered-phosphines with different alkyl spacer lengths have been prepared,tested and characterized.Lengthening the alkyl spacer of the tethered-phosphine improved the flexibility of tethered-phospine,promoted the formation of active species and enhanced the activity of hydroformylation over other tethered-phosphine modified Rh/SiO2 catalysts.
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financial support from the National Basic Research Program of China(973 Project,No.2015CB856603)the National Natural Science Foundation of China(Nos.20472096,21372241,21361140350,20672127,21421091,21372250,21121062,21302203,20732008 and 21572052)
文摘Nucleophilic chiral phosphine catalysis has been prosperous in asymmetric synthesis over the past two decades. Various tunable chiral phosphines display excellent activity and selectivity in asymmetric transformations including acycloaddition reactions and cycloaddition reactions. Enantiomerically enriched cyclic compounds are ubiquitous in natural products and drug molecules. These phosphinecatalyzed reactions provide effective and extensive strategies for the synthesis of a series of complex cyclic compounds as well as the synthesis of chiral compounds which could be easily transformed to carbocycles and heterocycles. This minireview summarizes recent developments in this area and highlights meaningful breakthroughs.
基金the Natural Science Foundation of China(Nos.21021001,21072134 and J1103315/J0104)for financial support
文摘The （COCl）2/Hantzsch ester is found to be an effective system for the metal-free reduction of tertiary phosphine oxides. The reaction proceeds under mild conditions, and is applicable to triarylphosphine oxides and alkyldiarylphosphine oxides to produce the corresponding tertiary phosphines in good to excellent yields. This new finding provides a practical, convenient and metal-free method for the reduction of tertiary phosphine oxides to tertiary phosphines, and shows potential application in organic synthesis.
基金supported by the National Natural Science Foundation of China(21473058,21273077)~~
文摘The neutral palladium（Ⅱ） complex bis-[1-（5＇-diphenylphosphinothiazol-2＇-yl）-imidazolyl]dichloropalladium（Ⅱ）（1A） ligated by thiazolylimidazolyl-based phosphine（L1） in which thiazolylimidazolyl acted as an S- and N-donor provider with weak coordinating nature,and the ionic complex bis-[1-（5＇-diphenylphosphinothiazol-2＇-yl）-3-methylimidazolium]dichloropalladium（Ⅱ） trifluoromethanesulfonate（2A） ligated by thiazolylimidazolium-based phosphine（L2） after quaternization of L1 using methyl trifluoromethanesulphonate were synthesized.It was found that the introduced positive charges and strong electron-withdrawing effect in 2A not only led to changes in the configuration and structural stability of the complex,but also lowered its catalytic performance in carbonylative Sonogashira reactions.These effects reveal the important role of the N-donor in 1A.In addition,as an ionic palladium complex,2A combined with the room-temperature ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate could be recycled eight times as the catalyst in carbonylative Sonogashira reactions without detectable metal leaching.
文摘[Objective] This study aimed to investigate the killing effect of mixed fumi- gation of phosphine and carbon dioxide on eggs of Lasioderma serricorne F. [Method] The outside-storage phosphine generator was placed in a tabernacled smoke box, and the mortality rates of L. serricome F. eggs in the smoke box under conditions of different aluminium phosphide usage amount and different fumigation time were studied. In addition, the times needed by tabernacle and smoke box cen- ter to reach the phosphine concentration peak were recorded. [Result] The optimum conditions for killing the eggs of L. serricorne were as follows： temperature of （27± 2） ℃, relatively humidity of （45±5）%, aluminium phosphide usage amount of 1.5 g/m3 and effective exposure time of 96 h. The killing effect of mixed fumigation of phos- phine and carbon dioxide was increased with the extension of fumigation time. The increased usage amount of aluminium phosphide showed no significant effect on killing effect. The tabernacle space and smoke box center all required relatively short time to reach the phosphine concentration peak. If the tabernacle had a good airtightness, the overall fumigation time could be shortened. [Conclusion] The fumi- gation method is reliable, and it can be used for the control of L. serricorne F. in tobacco storage.
基金financially supported by the National Natural Science Foundation of China(No.51203118)the Shanghai Automotive Industry Science and Technology Development Foundation(No.1006)
文摘To minimize the loading level of the char-forming phosphorus based flame retardants in the poly（lactic acid） （PLA） with reduced flammability, we have developed the flame-retarded PLA nanocomposites by melt blending method incorporating organically modified montmorillonite （OMMT） and aluminium diethylphosphinate （A1Pi） additives. The influence of A1Pi and OMMT on flame retardancy and thermal stability of PLA was thoroughly investigated by means of the limiting oxygen index （LOI）, UL94 test, cone calorimeter, X-ray diffraction （XRD）, thermogravimetric analysis and scanning electronic microscopy （SEM）. The experimental results show that the PLA/A1Pi/OMMT system has excellent fire retardancy. The LOI value increases from 19% for pristine PLA to 28% for the flame-retarded PLA. Cone calorimeter analysis of the PLA/A1Pi/OMMT exhibits a reduction in the peak heat release rate values by 26.2%. Thermogravimetric analysis and SEM of cone calorimeter residues indicate that OMMT significantly enhances the thermal stability, promotes char-forming and suppresses the melt dripping. The research of this study implies that the combining of the flame retardant and organoclay results in a synergistic effect. In addition, the flame-retarded PLA nanocomposite also exhibits notable increase in the impact strength and the elongation at break.
基金Supported by National Natural Science Foundation of China(41071305)~~
文摘[Objective] This study aimed to investigate the effects of phosphine on germination and physiological characteristics of rice seeds. [Method] Simulation envi- ronments were conducted to study the effects of high-level phosphine on germination status and physiological characteristics of rice seeds and explore the early environ- mental and ecological effects of phosphine on rice growth in phosphorus cycle of paddy field. [Result] Experimental results showed that the increase of phosphine con- centration in the environment resulted in the decrease of germination rate and ger- mination potential by 11.11% and 19.71%, respectively. In addition, the activities of catalase （CAT） and peroxidase （POD） were reduced to 94.35% and 92.61%, respec- tively; the content of malondialdehyde （MDA） was maximally increased by 29.11%, indicating that both germination potential and growth condition of rice seeds were in- hibited under conditions of high-level phosphine. [Conclusion] This study provided theoretical basis for investigating the effects of phosphine on germination of rice seeds under natural environment.
基金Funded by the National Natural Science Foundation of China(51566017)
文摘We prepared a kind of metal oxide-modified walnut-shell activated carbon(MWAC) by KOH chemical activation method and used for PH_3 adsorption removal. Meanwhile, the PH_3 adsorption equilibrium was investigated experimentally and fitted by the Toth equation, and the isosteric heat of PH_3 adsorption was calculated by the Clausius-Clapeyron Equation. The exhausted MWAC was regenerated by water washing and air drying. Moreover, the properties of five different samples were characterized by N_2 adsorption isotherm, SEM/EDS, XPS, and FTIR. The results showed that the maximum PH_3 equilibrium adsorption capacity was 595.56 mg/g. The MWAC had an energetically heterogeneous surface due to values of isosteric heat of adsorption ranging from 43 to 90 kJ/mol. The regeneration method provided an effective way for both adsorption species recycling and exhausted carbon regeneration. The high removal efficiency and big equilibrium adsorption capacity for PH_3 adsorption on the MWAC were related to its large surface area and high oxidation activity in PH_3 adsorption-oxidation to H_3 PO_4 and P_2 O_5. Furthermore, a possible PH_3 adsorption mechanism was proposed.
