The authors did not obtain permission to use some of the data from Prof.Hiroyuki Isobe,who supervised the reported study in itsearlystages.The concept of cyclo[n]helicenes was initiated by Prof.Hiroyuki Isobe(The Univ...The authors did not obtain permission to use some of the data from Prof.Hiroyuki Isobe,who supervised the reported study in itsearlystages.The concept of cyclo[n]helicenes was initiated by Prof.Hiroyuki Isobe(The University of Tokyo),then at Tohoku University.Specifically,the molecules 1-a,1-t,2-c,and 2-r were synthesized by Yong Yang who was employed with the funding of Professor Isobe,and the crystal data,CCDC 2306989-2306991 and 2306993,were obtained and analyzed by Sota Sato who was working in Professor Isobe’s group.The necessary expenses for these parts of the work were covered by JST ERATO(JPMJER1301,H.I.).The concept of cyclo[n]helicenes was initiated years ago by Prof.Isobe,when Dr.Yong Yang was a postdoc and Dr.Sota Sata was also a member of the group.The starting materials used in this work,[4]CH and[5]CH,were synthesized by Dr.Yang and structurally characterized by Dr.Sato in the group.展开更多
A highly strained macrocycle comprising four[4]helicene panels,[4]cyclo[4]helicenylene([4]CH,1),was synthesized through a one-pot macrocyclization and chemically reduced by alkali metals(Na and K),revealing a four-ele...A highly strained macrocycle comprising four[4]helicene panels,[4]cyclo[4]helicenylene([4]CH,1),was synthesized through a one-pot macrocyclization and chemically reduced by alkali metals(Na and K),revealing a four-electron reduction process.The resulting di-,tri-,and tetraanions of compound 1 were isolated and crystallographically characterized by X-ray diffraction.Owing to the four axially chiral bi[4]helicenyl fragments,a reversible stereo transformation of 1 between the(S,R,S,R)-and(S,S,R,R)-configurations was disclosed upon the twoelectron uptake,which was rationally understood by theoretical calculations.The(S,S,R,R)-configuration of 1^(2-)was further stabilized in triply reduced and tetra-reduced states,where structural deformation led by charges and metal complexation was observed.This study proposed an approach to alter the configuration of cycloarylenes in addition to thermal treatment.展开更多
The synthesis of stable open-shell hydrocarbon system comprising of pentagon defects and zigzag edges remains unexplored,which can be considered as model compounds for unraveling the spin-localized states in graphene ...The synthesis of stable open-shell hydrocarbon system comprising of pentagon defects and zigzag edges remains unexplored,which can be considered as model compounds for unraveling the spin-localized states in graphene edges.With concise synthetic approaches,twoπ-extended fluorenyl radicals were synthesized and isolated in their crystalline state.X-ray crystallographic analysis and studies on the magnetic,optical and electrochemical properties of neutral and charged species have revealed an interesting edge-dependence of the spin/charge distribution,that is,the spin and charge distribution shifted from the pentagon defects to the zigzag edges with the elongation of conjugation.Such phenomenon was unprecedented for hydrocarbon radicals and can be rationalized by the recovery of Clar Sextets in the dominant resonance structures.Remarkably,one of the radicals exhibited exceptional stability in air-saturated solutions with the half-life time up to 260 d,thus providing opportunities for the applications as electronic materials.展开更多
文摘The authors did not obtain permission to use some of the data from Prof.Hiroyuki Isobe,who supervised the reported study in itsearlystages.The concept of cyclo[n]helicenes was initiated by Prof.Hiroyuki Isobe(The University of Tokyo),then at Tohoku University.Specifically,the molecules 1-a,1-t,2-c,and 2-r were synthesized by Yong Yang who was employed with the funding of Professor Isobe,and the crystal data,CCDC 2306989-2306991 and 2306993,were obtained and analyzed by Sota Sato who was working in Professor Isobe’s group.The necessary expenses for these parts of the work were covered by JST ERATO(JPMJER1301,H.I.).The concept of cyclo[n]helicenes was initiated years ago by Prof.Isobe,when Dr.Yong Yang was a postdoc and Dr.Sota Sata was also a member of the group.The starting materials used in this work,[4]CH and[5]CH,were synthesized by Dr.Yang and structurally characterized by Dr.Sato in the group.
基金support from the National Natural Science Foundation of China(22301219,22201035)the Fundamental Research Funds for the Central Universities(22120240039,2242023R40024)+4 种基金the Start-up Research Fund of Southeast University(RF1028623055)the Shanghai Synchrotron Radiation Facility(2024-NFPS-PT-501026)JSPS KAKENHI(19H02552)We are grateful to Prof.Hiroyuki Isobe(University of Tokyo)for helpful discussions,and to KEK Photon Factory BL-17A beamline(2023G604 and 2021G589)SPring-8 BL38B1 and BL45XU beamlines(2018B1394 and 2021B1517)for the access to the X-ray diffraction instruments.
文摘A highly strained macrocycle comprising four[4]helicene panels,[4]cyclo[4]helicenylene([4]CH,1),was synthesized through a one-pot macrocyclization and chemically reduced by alkali metals(Na and K),revealing a four-electron reduction process.The resulting di-,tri-,and tetraanions of compound 1 were isolated and crystallographically characterized by X-ray diffraction.Owing to the four axially chiral bi[4]helicenyl fragments,a reversible stereo transformation of 1 between the(S,R,S,R)-and(S,S,R,R)-configurations was disclosed upon the twoelectron uptake,which was rationally understood by theoretical calculations.The(S,S,R,R)-configuration of 1^(2-)was further stabilized in triply reduced and tetra-reduced states,where structural deformation led by charges and metal complexation was observed.This study proposed an approach to alter the configuration of cycloarylenes in addition to thermal treatment.
基金support from the National Natural Science Foundation of China(Grant No.21971187)the Natural ScienceFoundationof Tianjin(19JCJQJC62700)the Haihe Laboratory of Sustainable Chemical Transformations。
文摘The synthesis of stable open-shell hydrocarbon system comprising of pentagon defects and zigzag edges remains unexplored,which can be considered as model compounds for unraveling the spin-localized states in graphene edges.With concise synthetic approaches,twoπ-extended fluorenyl radicals were synthesized and isolated in their crystalline state.X-ray crystallographic analysis and studies on the magnetic,optical and electrochemical properties of neutral and charged species have revealed an interesting edge-dependence of the spin/charge distribution,that is,the spin and charge distribution shifted from the pentagon defects to the zigzag edges with the elongation of conjugation.Such phenomenon was unprecedented for hydrocarbon radicals and can be rationalized by the recovery of Clar Sextets in the dominant resonance structures.Remarkably,one of the radicals exhibited exceptional stability in air-saturated solutions with the half-life time up to 260 d,thus providing opportunities for the applications as electronic materials.
