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
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
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
This work describes intermolecular acylfluorination of gem-difluoroenynes using acyl fluorides as both acyl source and fluorine source.Trifluoromethyl-substituted allenones or furans could be selectively achieved via ...This work describes intermolecular acylfluorination of gem-difluoroenynes using acyl fluorides as both acyl source and fluorine source.Trifluoromethyl-substituted allenones or furans could be selectively achieved via phosphine and silver catalysis.These approaches exhibit high regioselectivity,atom econ-omy and broad functionality tolerance.展开更多
An inexpensive phosphine catalyst was used effectively for a transition-metal-free acyl-transfer of N-containing heteroaryl ketones for the rapid synthesis of N-fused heterocycles.The key pre-aromatic spirocyclic inte...An inexpensive phosphine catalyst was used effectively for a transition-metal-free acyl-transfer of N-containing heteroaryl ketones for the rapid synthesis of N-fused heterocycles.The key pre-aromatic spirocyclic intermediate initialized by the single electron transfer(SET)process of Togni's reagentⅡpromoted by the tertiary phosphine resulted in an intriguing and alternative tactic for the cleavage of C–C bonds.By using inexpensive tertiary phosphine as the catalyst,this skeleton-reorganizing approach of N-containing heteroaryl ketones allows a streamlined assembly of complex N-fused heterocycles with broad functional group tolerance.展开更多
A mild,green,convenient and scalable N-bromosuccinimide(NBS)promoted direct phosphorylation strategy of secondary phosphine oxides and alcohols for the synthesis of various phosphinate esters was developed.A variety o...A mild,green,convenient and scalable N-bromosuccinimide(NBS)promoted direct phosphorylation strategy of secondary phosphine oxides and alcohols for the synthesis of various phosphinate esters was developed.A variety of substrates are well-tolerated and the desirable compounds were afforded in moderate to excellent yields(up to 92%).This reaction is conducted at room temperature without the addition of any oxidant and metal catalyst,which provides a new strategy for the synthesis of phosphinate esters.展开更多
Tertiary phosphines and their oxides react with oxalyl bromide to generate corresponding quaternary phosphonium salts,which can be further transformed as active intermediates to facilitate the bromination of alcohols ...Tertiary phosphines and their oxides react with oxalyl bromide to generate corresponding quaternary phosphonium salts,which can be further transformed as active intermediates to facilitate the bromination of alcohols and the dibromination of unsaturated hydrocarbons.This chemical process carries substantial research significance in the field of organic synthesis.In this study,two types of triaryl phosphine oxides and benzyl diaryl phosphine oxides containing alkyne groups were designed and synthesized.These compounds were then subjected to reaction with oxalyl bromide,resulting in the formation of novel benzophosphonium tribromides and trans-phosphoryl dibromoalkenes,respectively.These findings demonstrate variations from their reactions with oxalyl chloride.Furthermore,the benzophosphonium tribromide obtained can act as an alternative reagent for bromine,enabling the direct bromination of aromatics compounds,olefin,alkyne and acetophenone derivatives.展开更多
Phosphine-catalyzed[5+1]annulation reaction of Morita-Baylis-Hillman(MBH)carbonates with 1,3-dicarbonyl compounds has been developed,producing biologically interesting spirocyclohexene derivatives in high yields with ...Phosphine-catalyzed[5+1]annulation reaction of Morita-Baylis-Hillman(MBH)carbonates with 1,3-dicarbonyl compounds has been developed,producing biologically interesting spirocyclohexene derivatives in high yields with moderate to excellent diastereoselectivities.The annulation was achieved through sequential 1,6-conjugate addition/nucleophilic substution reaction of phosphine ylides with dinucleophiles.展开更多
Cesium carbonate was used as a base to achieve the desulfurization reaction of alkenyl sulfonium salts and phosphine oxides at room temperature,forming C(sp2)—P bonds.This method features simple operation,mild reacti...Cesium carbonate was used as a base to achieve the desulfurization reaction of alkenyl sulfonium salts and phosphine oxides at room temperature,forming C(sp2)—P bonds.This method features simple operation,mild reaction conditions,and good functional group compatibility,offering a straightforward and efficient preparation route for terminal vinyl phosphine oxides.展开更多
A[4+4]annulation reaction for the construction of medium-sized N-heterocycles is reported.This process involves the generation of all-carbon 1,4-dipoles containing aπ-allylpalladium complex from Morita-Baylis-Hillman...A[4+4]annulation reaction for the construction of medium-sized N-heterocycles is reported.This process involves the generation of all-carbon 1,4-dipoles containing aπ-allylpalladium complex from Morita-Baylis-Hillman(MBH)carbonates under the catalysis of Pd/Synphos,which then undergo Michael addition/N-allylic alkylation with 1-azadienes.A spectrum of eight-membered N-heterocycles featuring a trisubstituted exo-cyclic double bond is furnished efficiently with moderate to good E/Z selectivity and moderate atroposelectivity.In addition,moderate enantioselectivity can be realized by using a chiral ligand or with the assistant of a chiral quaternary ammonium salt.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
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.
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).
基金support from the National Natural Science Foundation of China(Nos.21971107,22071101,22271147).
文摘This work describes intermolecular acylfluorination of gem-difluoroenynes using acyl fluorides as both acyl source and fluorine source.Trifluoromethyl-substituted allenones or furans could be selectively achieved via phosphine and silver catalysis.These approaches exhibit high regioselectivity,atom econ-omy and broad functionality tolerance.
基金the financial support from the National Natural Science Foundation of China(Nos.21971205 and 22271231)the Natural Science Basic Research Plan in Shaanxi Province of China(No.2023-JC-YB-126)+1 种基金Natural Science Basic Research Plan for Distinguished Young Scholars in Shaanxi Province of China(No.2022JC-08)Key Research and Invention Program in Shaanxi Province of China(No.2021SF-299)。
文摘An inexpensive phosphine catalyst was used effectively for a transition-metal-free acyl-transfer of N-containing heteroaryl ketones for the rapid synthesis of N-fused heterocycles.The key pre-aromatic spirocyclic intermediate initialized by the single electron transfer(SET)process of Togni's reagentⅡpromoted by the tertiary phosphine resulted in an intriguing and alternative tactic for the cleavage of C–C bonds.By using inexpensive tertiary phosphine as the catalyst,this skeleton-reorganizing approach of N-containing heteroaryl ketones allows a streamlined assembly of complex N-fused heterocycles with broad functional group tolerance.
文摘A mild,green,convenient and scalable N-bromosuccinimide(NBS)promoted direct phosphorylation strategy of secondary phosphine oxides and alcohols for the synthesis of various phosphinate esters was developed.A variety of substrates are well-tolerated and the desirable compounds were afforded in moderate to excellent yields(up to 92%).This reaction is conducted at room temperature without the addition of any oxidant and metal catalyst,which provides a new strategy for the synthesis of phosphinate esters.
文摘Tertiary phosphines and their oxides react with oxalyl bromide to generate corresponding quaternary phosphonium salts,which can be further transformed as active intermediates to facilitate the bromination of alcohols and the dibromination of unsaturated hydrocarbons.This chemical process carries substantial research significance in the field of organic synthesis.In this study,two types of triaryl phosphine oxides and benzyl diaryl phosphine oxides containing alkyne groups were designed and synthesized.These compounds were then subjected to reaction with oxalyl bromide,resulting in the formation of novel benzophosphonium tribromides and trans-phosphoryl dibromoalkenes,respectively.These findings demonstrate variations from their reactions with oxalyl chloride.Furthermore,the benzophosphonium tribromide obtained can act as an alternative reagent for bromine,enabling the direct bromination of aromatics compounds,olefin,alkyne and acetophenone derivatives.
文摘Phosphine-catalyzed[5+1]annulation reaction of Morita-Baylis-Hillman(MBH)carbonates with 1,3-dicarbonyl compounds has been developed,producing biologically interesting spirocyclohexene derivatives in high yields with moderate to excellent diastereoselectivities.The annulation was achieved through sequential 1,6-conjugate addition/nucleophilic substution reaction of phosphine ylides with dinucleophiles.
文摘Cesium carbonate was used as a base to achieve the desulfurization reaction of alkenyl sulfonium salts and phosphine oxides at room temperature,forming C(sp2)—P bonds.This method features simple operation,mild reaction conditions,and good functional group compatibility,offering a straightforward and efficient preparation route for terminal vinyl phosphine oxides.
文摘A[4+4]annulation reaction for the construction of medium-sized N-heterocycles is reported.This process involves the generation of all-carbon 1,4-dipoles containing aπ-allylpalladium complex from Morita-Baylis-Hillman(MBH)carbonates under the catalysis of Pd/Synphos,which then undergo Michael addition/N-allylic alkylation with 1-azadienes.A spectrum of eight-membered N-heterocycles featuring a trisubstituted exo-cyclic double bond is furnished efficiently with moderate to good E/Z selectivity and moderate atroposelectivity.In addition,moderate enantioselectivity can be realized by using a chiral ligand or with the assistant of a chiral quaternary ammonium salt.
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.
