By virtue of the atom-and step-economy, utilization of simple arenes as a supplant of pre-prepared aryl metal species or aryl halides for the synthesis of arylated chiral molecules has attracted great attention from t...By virtue of the atom-and step-economy, utilization of simple arenes as a supplant of pre-prepared aryl metal species or aryl halides for the synthesis of arylated chiral molecules has attracted great attention from the synthetic community. While transition-metal-catalyzed enantioselective diarylation of tethered alkenes has been employed to prepare important chiral cyclic compounds, the direct use of simple arenes as aryl precursors is still underdeveloped, probably due to the difficulties in the effective control of the reactivity, site-selectivity and/or enantioselectivity. Herein we report an asymmetric Pd/Ag dual metal catalytic system for the non-directed, site-and enantioselective domino Heck/intermolecular C–H functionalization of arenes.Mechanistic studies showed that Pd and Ag act in cooperation in the catalysis and the chiral bisphosphine ligand plays a bifunctional role, i.e., assisting the silver species in the cleavage of the aryl C–H bond, while inducing the enantioselectivity on direct complexation with palladium. This method provides an efficient approach to the corresponding chiral oxindoles with good enantiomeric excesses from a broad scope of arenes, including fluoroarenes, heteroarenes and several complex products derived from medicines or natural products.展开更多
Enantioselective intermolecular three-component oxysulfenylations of alkenes with phenols and alcohols as O-nucleophiles were achieved using chiral BINAM-derived sulfide/phosphoric acid as the cocatalyst.Notably,chira...Enantioselective intermolecular three-component oxysulfenylations of alkenes with phenols and alcohols as O-nucleophiles were achieved using chiral BINAM-derived sulfide/phosphoric acid as the cocatalyst.Notably,chiral BINAM-derived sulfide/phosphoric acid co-catalysis was first explored to successfully catalyze highly enantioselective transformation.A variety of sulfur-containing benzylic aryl ethers and benzylic alkyl ethers,which contained two contiguous chiral stereocenters,were obtained readily in moderate to excellent yields with high to excellent enantioselectivities.展开更多
Due to new mechanism of action and ecofriendly characteristics,dicarboxamide insecticides have attracted more and more attentions in modern pest management.A series of 20 dual chiral N-cyano sulfilimines containing tw...Due to new mechanism of action and ecofriendly characteristics,dicarboxamide insecticides have attracted more and more attentions in modern pest management.A series of 20 dual chiral N-cyano sulfilimines containing two centers（carbon and sulfur） were designed and synthesized.All title compounds were determined by ^1H NMR,high-resolution mass spectrometry（HRMS） and optical polarimeter.The preliminary results indicated that some of them exhibited favourable insecticidal activities against oriental armyworm（Pseudaletia separata Walker）.These isomers exhibited different impact on activity following the sequence as（Sc,Ss） 〉（Sc,Rs）,and the rule of title compounds＇ activity against oriental armyworm was 3-CF3≥2—CH3—4—Cl〉2,3,4-trifluro in the anilide moiety.The results indicated that these groups such as 3-CF3,2—CH3—4—Cl or 2,3,4-trifluro were inefficient to replace heptafluoroisopropyl group for high larvicidal activity,which provided some guidance for the further modifications of sulfiliminyl dicarboxamides.展开更多
In this paper,we investigate the behaviors of dual fermion condensate in QED 3 under variation of temperature.By means of Dyson-Schwinger equation for the fermion propagator,we extract the dual fermion condensate and ...In this paper,we investigate the behaviors of dual fermion condensate in QED 3 under variation of temperature.By means of Dyson-Schwinger equation for the fermion propagator,we extract the dual fermion condensate and compare its behavior with the ordinary chiral fermion condensate and the chiral susceptibility.It is found that the dual fermion condensate cannot be regarded as the order parameter for the confinement-deconfinement phase transition in QED 3.Furthermore,the change of the dual fermion condensate around the chiral phase transition point observed in the present work must therefore be interpreted as solely induced by the chiral transition.展开更多
We report the rational design of a dual stimulus-activated quaternary chiral emission nematic liquid crystals(Q-N*-LCs)containing light-driven chiral dopant R-S-R-1,a static chiral dopant S-2 and an achiral Nile Red(N...We report the rational design of a dual stimulus-activated quaternary chiral emission nematic liquid crystals(Q-N*-LCs)containing light-driven chiral dopant R-S-R-1,a static chiral dopant S-2 and an achiral Nile Red(NR)in a nematic liquid crystal(SLC1717).The dopant R-S-R-1 acts as a dynamic chiral donor and an energy donor,and the achiral NR serves as a circularly polarized luminescence(CPL)emitter and energy acceptor.Interestingly,this kind of Q-N*-LCs appears reversal CPL emission direction(L-CPL)using 365 nm UV light irradiation compared with the initial state(R-CPL).Most importantly,the“On-Off”CPL switch behavior of Q-N*-LCs can be repeatedly driven by revoking or rearranging the applied direct current(DC)electric field.An OR chiral information logic gate demonstrates that this dual driven Q-N*-LCs can be potentially used for chiral information storage and coding.展开更多
基金supported by the National Key R&D Program of China (2021YFA1500100)the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB0610000)+2 种基金the National Natural Science Foundation of China (92256303, 22171278, 21821002)the Shanghai Science and Technology Committee (23ZR1482400)the Natural Science Foundation of Ningbo (2023J034)。
文摘By virtue of the atom-and step-economy, utilization of simple arenes as a supplant of pre-prepared aryl metal species or aryl halides for the synthesis of arylated chiral molecules has attracted great attention from the synthetic community. While transition-metal-catalyzed enantioselective diarylation of tethered alkenes has been employed to prepare important chiral cyclic compounds, the direct use of simple arenes as aryl precursors is still underdeveloped, probably due to the difficulties in the effective control of the reactivity, site-selectivity and/or enantioselectivity. Herein we report an asymmetric Pd/Ag dual metal catalytic system for the non-directed, site-and enantioselective domino Heck/intermolecular C–H functionalization of arenes.Mechanistic studies showed that Pd and Ag act in cooperation in the catalysis and the chiral bisphosphine ligand plays a bifunctional role, i.e., assisting the silver species in the cleavage of the aryl C–H bond, while inducing the enantioselectivity on direct complexation with palladium. This method provides an efficient approach to the corresponding chiral oxindoles with good enantiomeric excesses from a broad scope of arenes, including fluoroarenes, heteroarenes and several complex products derived from medicines or natural products.
基金the National Natural Science Foundation of China(NSFC)(nos.21871178,22071149,21901158,21702135)and the STCSM(no.19JC1430100)for their financial support.
文摘Enantioselective intermolecular three-component oxysulfenylations of alkenes with phenols and alcohols as O-nucleophiles were achieved using chiral BINAM-derived sulfide/phosphoric acid as the cocatalyst.Notably,chiral BINAM-derived sulfide/phosphoric acid co-catalysis was first explored to successfully catalyze highly enantioselective transformation.A variety of sulfur-containing benzylic aryl ethers and benzylic alkyl ethers,which contained two contiguous chiral stereocenters,were obtained readily in moderate to excellent yields with high to excellent enantioselectivities.
基金supported by National Natural Science Foundation of China(No.21602118)Innovation Center of Chemical Science and Engineering(Tianjin)the National Natural Science Foundation of China(No.21302104)
文摘Due to new mechanism of action and ecofriendly characteristics,dicarboxamide insecticides have attracted more and more attentions in modern pest management.A series of 20 dual chiral N-cyano sulfilimines containing two centers（carbon and sulfur） were designed and synthesized.All title compounds were determined by ^1H NMR,high-resolution mass spectrometry（HRMS） and optical polarimeter.The preliminary results indicated that some of them exhibited favourable insecticidal activities against oriental armyworm（Pseudaletia separata Walker）.These isomers exhibited different impact on activity following the sequence as（Sc,Ss） 〉（Sc,Rs）,and the rule of title compounds＇ activity against oriental armyworm was 3-CF3≥2—CH3—4—Cl〉2,3,4-trifluro in the anilide moiety.The results indicated that these groups such as 3-CF3,2—CH3—4—Cl or 2,3,4-trifluro were inefficient to replace heptafluoroisopropyl group for high larvicidal activity,which provided some guidance for the further modifications of sulfiliminyl dicarboxamides.
基金supported by the National Natural Science Foundation of China (Grant Nos.11047005,11105029,10935001 and 11075075)
文摘In this paper,we investigate the behaviors of dual fermion condensate in QED 3 under variation of temperature.By means of Dyson-Schwinger equation for the fermion propagator,we extract the dual fermion condensate and compare its behavior with the ordinary chiral fermion condensate and the chiral susceptibility.It is found that the dual fermion condensate cannot be regarded as the order parameter for the confinement-deconfinement phase transition in QED 3.Furthermore,the change of the dual fermion condensate around the chiral phase transition point observed in the present work must therefore be interpreted as solely induced by the chiral transition.
基金supported by the National Natural Science Foundation of China (21975118,92156014)
文摘We report the rational design of a dual stimulus-activated quaternary chiral emission nematic liquid crystals(Q-N*-LCs)containing light-driven chiral dopant R-S-R-1,a static chiral dopant S-2 and an achiral Nile Red(NR)in a nematic liquid crystal(SLC1717).The dopant R-S-R-1 acts as a dynamic chiral donor and an energy donor,and the achiral NR serves as a circularly polarized luminescence(CPL)emitter and energy acceptor.Interestingly,this kind of Q-N*-LCs appears reversal CPL emission direction(L-CPL)using 365 nm UV light irradiation compared with the initial state(R-CPL).Most importantly,the“On-Off”CPL switch behavior of Q-N*-LCs can be repeatedly driven by revoking or rearranging the applied direct current(DC)electric field.An OR chiral information logic gate demonstrates that this dual driven Q-N*-LCs can be potentially used for chiral information storage and coding.
