Alkyl chlorides are abundant and easily accessible starting materials.However,due to the high reduction potentials associated with unactivated alkyl chlorides,achieving their single electron reduction remains a persis...Alkyl chlorides are abundant and easily accessible starting materials.However,due to the high reduction potentials associated with unactivated alkyl chlorides,achieving their single electron reduction remains a persistent challenge.This challenge has spurred the exploration of efficient activation methods to overcome this issue.In recent years,photocatalysis has emerged as a mild and potent tool for the single electron reduction of unactivated alkyl chlorides,opening up new possibilities in this field.Considering the rapid advancements in this area,a comprehensive review that provides a conceptual understanding of this emerging field,with a specific focus on reaction design and catalytic mechanisms,would be timely and highly valuable.Hence,we present an overview of various synthetic techniques for photoinduced single electron reduction of unactivated alkyl chlorides.Furthermore,we also discuss the limitations of the present methods and future directions that lie ahead in this field.展开更多
Alkyl chlorides are robust precursors to carbon radicals;however,their relative inertness has hampered their practical use.Although modern photochemical strategies have greatly enhanced the utility of alkyl chlorides ...Alkyl chlorides are robust precursors to carbon radicals;however,their relative inertness has hampered their practical use.Although modern photochemical strategies have greatly enhanced the utility of alkyl chlorides as radical precursors,these methods often depend on strongly reducing conditions leading to unproductive side reactions.Here,we report a catalytic radical generation from 1°,2°,and 3°unactivated alkyl chlorides with zirconocene and photoredox catalysis,which enables both hydrogenation and borylation on a range of structurally complex molecules.This mild zirconocene-catalyzed protocol shows that zirconium can render the C−Cl bond cleavage more exergonic and can lower the activation energy of the transition state,amplifying the ability of metallocenes toward halogen atom transfer.展开更多
The cationic polymerizations of 1, 3-pentadiene were initiated by AlCl_3 in n-hexaneat 30℃ in the presence of alkyl halides, i.e., tert-butyl chloride, tert-butyl bromide andisobutyl chloride. The effects of these ha...The cationic polymerizations of 1, 3-pentadiene were initiated by AlCl_3 in n-hexaneat 30℃ in the presence of alkyl halides, i.e., tert-butyl chloride, tert-butyl bromide andisobutyl chloride. The effects of these halides on the polymer yield, molecular weight,crosslinking reaction, cyclization and polymer microstructure, have been investigated. Twomain side reactions, crosslinking and cyclization, were suppressed and reduced by theaddition of the halides. The proportion of 1, 4 units of polymer chains was increasedby the presence of the halides, which reduced the polymer yield and the molecular weightof polymers.展开更多
A convenient synthetic approach leading to protected inositol was described based on regioselective O-alkylation using alkyl halide under solid-liquid PTC condition
Five novel bis—(N—alkyl—N,N—dimethyl ammoni(?)n)polyethyleneglyool ether salts prepared by our previously reported proced(?)e show high catalytic efficiency in the condensation of 1,4—diacetyl— 2,5—piperazinedi...Five novel bis—(N—alkyl—N,N—dimethyl ammoni(?)n)polyethyleneglyool ether salts prepared by our previously reported proced(?)e show high catalytic efficiency in the condensation of 1,4—diacetyl— 2,5—piperazinedione and aldehydes at both higher and lower temperature even in lower concentration.They al so show catalytic selectivity at lower temperature.展开更多
为了提升经济效益,甲醇制汽油（MTG）生产企业配套MTG副产重质芳烃的再加工工艺是首选方案之一。在非临氢条件下,以甲苯为烷基授体,通过20 m L小试评价装置和100 m L中试评价装置,考察了TCDTO-1催化剂对富含均四甲苯的MTG重质芳烃的轻...为了提升经济效益,甲醇制汽油（MTG）生产企业配套MTG副产重质芳烃的再加工工艺是首选方案之一。在非临氢条件下,以甲苯为烷基授体,通过20 m L小试评价装置和100 m L中试评价装置,考察了TCDTO-1催化剂对富含均四甲苯的MTG重质芳烃的轻质化效果。小试结果表明,TCDTO-1催化剂对模型化合物中的甲苯转化率≥50%,均四甲苯转化率≥68%,产物中C8~C9芳烃选择性≥80%。中试结果表明,以MTG工业重质芳烃为原料时,TCDTO-1催化剂的甲苯转化率≥45%,均四甲苯转化率≥55%,产物中C8~C9芳烃选择性≥85%,催化剂稳定运行时间达到60 d,液态烃类累计收率≥99%。轻质化后的产物与轻汽油馏分调和后,可满足国V汽油指标。展开更多
A simple and environmentally friendly method is described for the efficient conversion of alkyl halide to alkyl thiocyanate using tetrabutylammonium bromide （TBAB） as a phase transfer catalyst. The reactions occur i...A simple and environmentally friendly method is described for the efficient conversion of alkyl halide to alkyl thiocyanate using tetrabutylammonium bromide （TBAB） as a phase transfer catalyst. The reactions occur in water and furnish the corresponding alkyl thiocyanate in high yields. No evidence for the formation of isothiocyanates as by-product of the reaction was observed and the products were obtained in pure form without further purification.展开更多
Linear Alkyl Benzene （LAB） is a promising liquid scintillator solvent in neutrino experiments because it has many appealing properties. The timing properties of LAB-based liquid scintillator have been studied throug...Linear Alkyl Benzene （LAB） is a promising liquid scintillator solvent in neutrino experiments because it has many appealing properties. The timing properties of LAB-based liquid scintillator have been studied through ultraviolet and ionization excitation in this study. The decay time of LAB, PPO and bis-MSB is found to be 48.6 ns, 1.55 ns and 1.5 ns, respectively. A model can describe the absorption and re-emission process between PPO and bis-MSB perfectly. The energy transfer time between LAB and PPO with different concentrations can be obtained via another model. We also show that the LAB-based liquid scintillator has good （n, γ） and （α, γ） discrimination power.展开更多
1,4-Bis（triphenylphosphonium）-2-butene dichloride（BTPBDC） and 1,4-bis（triphenyl phosphonium）-2-butene dithiocyanate （BTPBDT） were prepared and used as phase-transfer catalysts.Alkyl halides were converted effi...1,4-Bis（triphenylphosphonium）-2-butene dichloride（BTPBDC） and 1,4-bis（triphenyl phosphonium）-2-butene dithiocyanate （BTPBDT） were prepared and used as phase-transfer catalysts.Alkyl halides were converted efficiently to the corresponding alkyl thiocyanates under mild reaction conditions in water.No evidence for the formation of isothiocyanates as by-product of the reaction was observed.展开更多
基金supported by the National Natural Science Foundation of China (22001248)the Fundamental Research Funds for the Central Universitiesthe University of the Chinese Academy of Sciences。
文摘Alkyl chlorides are abundant and easily accessible starting materials.However,due to the high reduction potentials associated with unactivated alkyl chlorides,achieving their single electron reduction remains a persistent challenge.This challenge has spurred the exploration of efficient activation methods to overcome this issue.In recent years,photocatalysis has emerged as a mild and potent tool for the single electron reduction of unactivated alkyl chlorides,opening up new possibilities in this field.Considering the rapid advancements in this area,a comprehensive review that provides a conceptual understanding of this emerging field,with a specific focus on reaction design and catalytic mechanisms,would be timely and highly valuable.Hence,we present an overview of various synthetic techniques for photoinduced single electron reduction of unactivated alkyl chlorides.Furthermore,we also discuss the limitations of the present methods and future directions that lie ahead in this field.
文摘Alkyl chlorides are robust precursors to carbon radicals;however,their relative inertness has hampered their practical use.Although modern photochemical strategies have greatly enhanced the utility of alkyl chlorides as radical precursors,these methods often depend on strongly reducing conditions leading to unproductive side reactions.Here,we report a catalytic radical generation from 1°,2°,and 3°unactivated alkyl chlorides with zirconocene and photoredox catalysis,which enables both hydrogenation and borylation on a range of structurally complex molecules.This mild zirconocene-catalyzed protocol shows that zirconium can render the C−Cl bond cleavage more exergonic and can lower the activation energy of the transition state,amplifying the ability of metallocenes toward halogen atom transfer.
文摘The cationic polymerizations of 1, 3-pentadiene were initiated by AlCl_3 in n-hexaneat 30℃ in the presence of alkyl halides, i.e., tert-butyl chloride, tert-butyl bromide andisobutyl chloride. The effects of these halides on the polymer yield, molecular weight,crosslinking reaction, cyclization and polymer microstructure, have been investigated. Twomain side reactions, crosslinking and cyclization, were suppressed and reduced by theaddition of the halides. The proportion of 1, 4 units of polymer chains was increasedby the presence of the halides, which reduced the polymer yield and the molecular weightof polymers.
文摘A convenient synthetic approach leading to protected inositol was described based on regioselective O-alkylation using alkyl halide under solid-liquid PTC condition
文摘Five novel bis—(N—alkyl—N,N—dimethyl ammoni(?)n)polyethyleneglyool ether salts prepared by our previously reported proced(?)e show high catalytic efficiency in the condensation of 1,4—diacetyl— 2,5—piperazinedione and aldehydes at both higher and lower temperature even in lower concentration.They al so show catalytic selectivity at lower temperature.
文摘为了提升经济效益,甲醇制汽油（MTG）生产企业配套MTG副产重质芳烃的再加工工艺是首选方案之一。在非临氢条件下,以甲苯为烷基授体,通过20 m L小试评价装置和100 m L中试评价装置,考察了TCDTO-1催化剂对富含均四甲苯的MTG重质芳烃的轻质化效果。小试结果表明,TCDTO-1催化剂对模型化合物中的甲苯转化率≥50%,均四甲苯转化率≥68%,产物中C8~C9芳烃选择性≥80%。中试结果表明,以MTG工业重质芳烃为原料时,TCDTO-1催化剂的甲苯转化率≥45%,均四甲苯转化率≥55%,产物中C8~C9芳烃选择性≥85%,催化剂稳定运行时间达到60 d,液态烃类累计收率≥99%。轻质化后的产物与轻汽油馏分调和后,可满足国V汽油指标。
基金Partial support for this work by Chamran University Research Council is gratefully acknowledged.
文摘A simple and environmentally friendly method is described for the efficient conversion of alkyl halide to alkyl thiocyanate using tetrabutylammonium bromide （TBAB） as a phase transfer catalyst. The reactions occur in water and furnish the corresponding alkyl thiocyanate in high yields. No evidence for the formation of isothiocyanates as by-product of the reaction was observed and the products were obtained in pure form without further purification.
基金Supported by National Natural Science Foundation of China (10890094, 11011120080)
文摘Linear Alkyl Benzene （LAB） is a promising liquid scintillator solvent in neutrino experiments because it has many appealing properties. The timing properties of LAB-based liquid scintillator have been studied through ultraviolet and ionization excitation in this study. The decay time of LAB, PPO and bis-MSB is found to be 48.6 ns, 1.55 ns and 1.5 ns, respectively. A model can describe the absorption and re-emission process between PPO and bis-MSB perfectly. The energy transfer time between LAB and PPO with different concentrations can be obtained via another model. We also show that the LAB-based liquid scintillator has good （n, γ） and （α, γ） discrimination power.
文摘1,4-Bis（triphenylphosphonium）-2-butene dichloride（BTPBDC） and 1,4-bis（triphenyl phosphonium）-2-butene dithiocyanate （BTPBDT） were prepared and used as phase-transfer catalysts.Alkyl halides were converted efficiently to the corresponding alkyl thiocyanates under mild reaction conditions in water.No evidence for the formation of isothiocyanates as by-product of the reaction was observed.
