A quantum mechanical calculation was performed to study the hydrogen atom transfer of collinear OH…O/OD…O system, for which Delves' coordinates and R-matrix propagation method were applied in a Melius-Blint pote...A quantum mechanical calculation was performed to study the hydrogen atom transfer of collinear OH…O/OD…O system, for which Delves' coordinates and R-matrix propagation method were applied in a Melius-Blint potential energy surface. The calculation result showed that the state-state H atom transfer probability comported strong oscillation phenomena and collision delay time of the title system was in the fs-ps time scale. The kinetic isotope effect was calculated in this work too.展开更多
Deuterium labeling techniques are widely utilized as efficient tools to study the absorption,distribution,metabolism,and excretion(ADME)of pharmaceuticals.Moreover,deuterium‐labeled drugs are expected to prolong the ...Deuterium labeling techniques are widely utilized as efficient tools to study the absorption,distribution,metabolism,and excretion(ADME)of pharmaceuticals.Moreover,deuterium‐labeled drugs are expected to prolong the half‐life of drug metabolism,enhance the efficacy of drugs,close metabolic sites,and decrease side effects.Thus,there is a rising demand for the practical construction of deuterium‐labeled drugs and their intermediates under mild conditions.This paper timely provides an overview of the recent advances in both photo‐and electro‐catalytic mild and selective deuteration of fine chemicals and pharmaceuticals with low‐cost and sustainable deuterium source.Three types of deuteration strategies are discussed according to the deuteration mode,named deuterium atom transfer strategy,deuterium atom abstraction strategy and deuterated water splitting strategy respectively.The application scope and mechanistic insights are discussed comprehensively.Finally,the perspective on the challenges and future development trends for photo‐and electro‐catalytic deuteration strategies are also presented.展开更多
H-type amphiphilic liquid crystalline block copolymers containing azobenzene were synthesized by atom transfer radical polymerization (ATRP). Macroinitiators prepared by the esterification between poly(ethylene ox...H-type amphiphilic liquid crystalline block copolymers containing azobenzene were synthesized by atom transfer radical polymerization (ATRP). Macroinitiators prepared by the esterification between poly(ethylene oxide) (PEG) and 2,2-dichloroacetyl chloride were utilized to initiate the polymerization of 6-[4-(4-ethoxyphenylazo)phenoxy]hexyl rnethacrylate (M6C). The resulting macroinitiators and block copolymers were characterized by ^1H NMR, gel permeation chromatography (GPC). Polarizing optical microscopy (POM) and differential scanning calorimetry (DSC) preliminarily revealed the liquid crystalline property of these block copolymers. This series of liquid crystalline block copolymers are promising in some areas, such as optical data storage, optical switch, and molecular devices.展开更多
Cross sections of electron-loss in H(1s)+ H(1s) collisions and total collisional destruction of H(2s) in H(1s) 4- H(2s) collisions are calculatted by four-body classical-trajectory Monte Caylo (CTMC) meth...Cross sections of electron-loss in H(1s)+ H(1s) collisions and total collisional destruction of H(2s) in H(1s) 4- H(2s) collisions are calculatted by four-body classical-trajectory Monte Caylo (CTMC) method and compared with previous theoretical and experimental data over the energy range of 4-100 keV. For the former a good agreement is obtained within different four-body CTMC calculations, and for the incident energy Ep 〉 10 keV, comparison with the experimental data shows a better agreement than the results calculated by the impact parameter approx- imation. For the latter, our theory predicts the correct experimental behaviour, and the discrepancies between our results and experimental ones are less than 30%. Based on the successive comparison with experiments, the cross sections for excitation to H(2p), single- and double-ionization and H- formation in H(2s)+H(2s) collisions are calculated in the energy range of 4-100 keV for the first time, and compared with those in H(1s)+H(1s) and H(1s)+U(2s) collisions.展开更多
通过亚胺自由基引发的1,5-氢原子转移(Hydrogen Atom Transfer,HAT)途径实现C(sp^(3))—H键官能团化,可避免导向基团和当量氧化剂的使用,因而引起了研究人员的广泛关注。近年来,过渡金属和可见光氧化还原体系的发展为高效可控产生亚胺...通过亚胺自由基引发的1,5-氢原子转移(Hydrogen Atom Transfer,HAT)途径实现C(sp^(3))—H键官能团化,可避免导向基团和当量氧化剂的使用,因而引起了研究人员的广泛关注。近年来,过渡金属和可见光氧化还原体系的发展为高效可控产生亚胺自由基提供了可靠的方法。本文根据亚胺自由基的来源分类总结了亚胺自由基引发的1,5-氢原子转移实现C(sp^(3))—H键官能团化反应。展开更多
Described herein is an efficient protocol for the regioselective introduction of a vinyl trifluoromethylthioether to remote unactivated C(sp3)–H bonds.The cascade process involves the vinyl radical-mediated 1,5-hydro...Described herein is an efficient protocol for the regioselective introduction of a vinyl trifluoromethylthioether to remote unactivated C(sp3)–H bonds.The cascade process involves the vinyl radical-mediated 1,5-hydrogen atom transfer(HAT)and remote vinyl migration.During the transformation,inert C–H and C–C bonds are consecutively cleaved under mild conditions.The reaction features good functional group tolerance,broad substrate scope,and high regio-/stereo-selectivity.展开更多
Based on theab initio calculation results, the hydrogen atom transfer has been investigated. In order to explain the experimental results, a new mechanism is proposed, that is, hydrogen transfer occurs before but not ...Based on theab initio calculation results, the hydrogen atom transfer has been investigated. In order to explain the experimental results, a new mechanism is proposed, that is, hydrogen transfer occurs before but not after CI atom eliminates from aromatic ring. The calculation result strongly supports this mechanism.展开更多
基金Project supported by the National Natural Science Foundation of China (No. 29873023).
文摘A quantum mechanical calculation was performed to study the hydrogen atom transfer of collinear OH…O/OD…O system, for which Delves' coordinates and R-matrix propagation method were applied in a Melius-Blint potential energy surface. The calculation result showed that the state-state H atom transfer probability comported strong oscillation phenomena and collision delay time of the title system was in the fs-ps time scale. The kinetic isotope effect was calculated in this work too.
文摘Deuterium labeling techniques are widely utilized as efficient tools to study the absorption,distribution,metabolism,and excretion(ADME)of pharmaceuticals.Moreover,deuterium‐labeled drugs are expected to prolong the half‐life of drug metabolism,enhance the efficacy of drugs,close metabolic sites,and decrease side effects.Thus,there is a rising demand for the practical construction of deuterium‐labeled drugs and their intermediates under mild conditions.This paper timely provides an overview of the recent advances in both photo‐and electro‐catalytic mild and selective deuteration of fine chemicals and pharmaceuticals with low‐cost and sustainable deuterium source.Three types of deuteration strategies are discussed according to the deuteration mode,named deuterium atom transfer strategy,deuterium atom abstraction strategy and deuterated water splitting strategy respectively.The application scope and mechanistic insights are discussed comprehensively.Finally,the perspective on the challenges and future development trends for photo‐and electro‐catalytic deuteration strategies are also presented.
基金financial support from the National Natural Science Foundation of China(No.20134020)the Science Research Fund of the Chinese Ministry of Education(No.104005)the Science Research Fund of Shandong Provincial Education Department of China(No.105D11).
文摘H-type amphiphilic liquid crystalline block copolymers containing azobenzene were synthesized by atom transfer radical polymerization (ATRP). Macroinitiators prepared by the esterification between poly(ethylene oxide) (PEG) and 2,2-dichloroacetyl chloride were utilized to initiate the polymerization of 6-[4-(4-ethoxyphenylazo)phenoxy]hexyl rnethacrylate (M6C). The resulting macroinitiators and block copolymers were characterized by ^1H NMR, gel permeation chromatography (GPC). Polarizing optical microscopy (POM) and differential scanning calorimetry (DSC) preliminarily revealed the liquid crystalline property of these block copolymers. This series of liquid crystalline block copolymers are promising in some areas, such as optical data storage, optical switch, and molecular devices.
基金Supported by the National Natural Science Foundation of China under Grant Nos 10434100, 10574018 and 10574020.
文摘Cross sections of electron-loss in H(1s)+ H(1s) collisions and total collisional destruction of H(2s) in H(1s) 4- H(2s) collisions are calculatted by four-body classical-trajectory Monte Caylo (CTMC) method and compared with previous theoretical and experimental data over the energy range of 4-100 keV. For the former a good agreement is obtained within different four-body CTMC calculations, and for the incident energy Ep 〉 10 keV, comparison with the experimental data shows a better agreement than the results calculated by the impact parameter approx- imation. For the latter, our theory predicts the correct experimental behaviour, and the discrepancies between our results and experimental ones are less than 30%. Based on the successive comparison with experiments, the cross sections for excitation to H(2p), single- and double-ionization and H- formation in H(2s)+H(2s) collisions are calculated in the energy range of 4-100 keV for the first time, and compared with those in H(1s)+H(1s) and H(1s)+U(2s) collisions.
基金supported by USTC Research Funds of the Double First-Class Initiative(YD2060002024)Youth Innovation Promotion Association CAS(2020448)+2 种基金National Natur-al Science Foundation of China(22171254)Anhui Provincial Natural Science Foundation(2108085MB58)Start-up Research Fund from University of Science and Technology of China(KY2060000216).
文摘通过亚胺自由基引发的1,5-氢原子转移(Hydrogen Atom Transfer,HAT)途径实现C(sp^(3))—H键官能团化,可避免导向基团和当量氧化剂的使用,因而引起了研究人员的广泛关注。近年来,过渡金属和可见光氧化还原体系的发展为高效可控产生亚胺自由基提供了可靠的方法。本文根据亚胺自由基的来源分类总结了亚胺自由基引发的1,5-氢原子转移实现C(sp^(3))—H键官能团化反应。
基金supported by Soochow University,the National Natural Science Foundation of China(21722205)the Project of Scientific and Technologic Infrastructure of Suzhou(SZS201708)the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Described herein is an efficient protocol for the regioselective introduction of a vinyl trifluoromethylthioether to remote unactivated C(sp3)–H bonds.The cascade process involves the vinyl radical-mediated 1,5-hydrogen atom transfer(HAT)and remote vinyl migration.During the transformation,inert C–H and C–C bonds are consecutively cleaved under mild conditions.The reaction features good functional group tolerance,broad substrate scope,and high regio-/stereo-selectivity.
文摘Based on theab initio calculation results, the hydrogen atom transfer has been investigated. In order to explain the experimental results, a new mechanism is proposed, that is, hydrogen transfer occurs before but not after CI atom eliminates from aromatic ring. The calculation result strongly supports this mechanism.