Water radical cations,the crucial intermediates in many aqueous reactions and biochemical processes,are difficult to investigate experimentally due to their short lifetime andlowabundance.Herein,ahomemade device based...Water radical cations,the crucial intermediates in many aqueous reactions and biochemical processes,are difficult to investigate experimentally due to their short lifetime andlowabundance.Herein,ahomemade device based on energy-tunable discharge was employed to deposit suitable amounts of energy to atmospheric pressure pure water vapor for abundant production of water radical cations,stabilized as(H_(2)O)n^(+·)(n=2-5)with a maximal abundance of≥8.3×10^(6) cps for(H_(2)O)_(2)^(+·),characterized by mass spectrometry(MS).The abundance of water radical cations was optimized by adjusting the experimental parameters such as the discharge voltage(2.5 kV),temperature of the MS inlet(140℃),carrier gas flow(20mL/min),and the distance between the discharge tip and MS inlet(12 mm).The ambient formation of water radical cationswas further confirmedby thehigh reactivity of as-prepared water radical cations,which reacted with benzene,ethyl acetate,and dimethyl disulfide instantly,showing rich chemistry with ionic and radical characteristics.Moreover,the computations usingCCSD(T)//MP2 method and density functional theory confirmed that the O-O single-electron bound dimer(B),as well as the hydronium hydroxyl radical complex(A),accounted for the unusual chemistry of the water radical cations,providing a facile approach to access the high reactivity ofwater radical cations under the ambient conditions.展开更多
Two naphthalene（NP） and bipyridinium（BIPY^2＋） alternately incorporated polymers P1 and P2 have been prepared through the formation of dynamic hydrazone bonds. The polymers formed NP–BIPY^2＋donor–acceptor inter...Two naphthalene（NP） and bipyridinium（BIPY^2＋） alternately incorporated polymers P1 and P2 have been prepared through the formation of dynamic hydrazone bonds. The polymers formed NP–BIPY^2＋donor–acceptor interaction-induced pleated secondary structure. Upon reducing the BIPY^2＋units to radical cation BIPY＋, intramolecular dimerization of the BIPY＋units induced the backbones to afford another pleated secondary structure. Adding electron-rich macrocyclic polyether bis-1,5-dinaphtho[38]crown-10 or electron-deficient cyclobis（paraquat-p-phenylene） cyclophane did not break the first foldamer by complexing the BIPY^2＋or NP units of the polymers, whereas the di（radical cationic）ring of the second cyclophane could break the second foldamer by forming threading complexes with the BIPY＋units of the polymers.展开更多
基金supported by a grant from the National Natural Science Foundation of China(grant no.215201-02007)the US National Science Foundation(grant no.1905087).
文摘Water radical cations,the crucial intermediates in many aqueous reactions and biochemical processes,are difficult to investigate experimentally due to their short lifetime andlowabundance.Herein,ahomemade device based on energy-tunable discharge was employed to deposit suitable amounts of energy to atmospheric pressure pure water vapor for abundant production of water radical cations,stabilized as(H_(2)O)n^(+·)(n=2-5)with a maximal abundance of≥8.3×10^(6) cps for(H_(2)O)_(2)^(+·),characterized by mass spectrometry(MS).The abundance of water radical cations was optimized by adjusting the experimental parameters such as the discharge voltage(2.5 kV),temperature of the MS inlet(140℃),carrier gas flow(20mL/min),and the distance between the discharge tip and MS inlet(12 mm).The ambient formation of water radical cationswas further confirmedby thehigh reactivity of as-prepared water radical cations,which reacted with benzene,ethyl acetate,and dimethyl disulfide instantly,showing rich chemistry with ionic and radical characteristics.Moreover,the computations usingCCSD(T)//MP2 method and density functional theory confirmed that the O-O single-electron bound dimer(B),as well as the hydronium hydroxyl radical complex(A),accounted for the unusual chemistry of the water radical cations,providing a facile approach to access the high reactivity ofwater radical cations under the ambient conditions.
基金supported by The Ministry of Science and Technology of China (No. 2013CB834501)The Science and Technology Commission of Shanghai Municipality (No. 13M1400200)+1 种基金The Ministry of Education of China research fund for the doctoral programthe National Natural Science Foundation of China (Nos. 21432004 and 21472023)
文摘Two naphthalene（NP） and bipyridinium（BIPY^2＋） alternately incorporated polymers P1 and P2 have been prepared through the formation of dynamic hydrazone bonds. The polymers formed NP–BIPY^2＋donor–acceptor interaction-induced pleated secondary structure. Upon reducing the BIPY^2＋units to radical cation BIPY＋, intramolecular dimerization of the BIPY＋units induced the backbones to afford another pleated secondary structure. Adding electron-rich macrocyclic polyether bis-1,5-dinaphtho[38]crown-10 or electron-deficient cyclobis（paraquat-p-phenylene） cyclophane did not break the first foldamer by complexing the BIPY^2＋or NP units of the polymers, whereas the di（radical cationic）ring of the second cyclophane could break the second foldamer by forming threading complexes with the BIPY＋units of the polymers.
