The precise synthesis of helicenes with topologically defined length and specific heteroatomic perturbation in the screw-like conjugated skeletons plays an emerging role in the manipulation of chiral materials.Facile,...The precise synthesis of helicenes with topologically defined length and specific heteroatomic perturbation in the screw-like conjugated skeletons plays an emerging role in the manipulation of chiral materials.Facile,selective,and programmable routes to helicenes or heterohelicenes are highly desirable yet challenging for structure-chiroptical property relationship studies.Herein,we report the synthesis and characterization of NBN-doped helicenes with boron atoms in the inner rims,enabled by the highly regioselective one-pot borylation of rationally designed precursors with,namely,fold-in or pan-out manner.The incorporation of nonbonded boron and nitrogen atoms resulted in narrow-band emission and improved optical properties for the single-stranded carbon helix.In addition,numbers and arrangement modes of fused six-membered rings have distinct effects on configurational stability and chiroptical properties,revealing that BN-[6]H with strong circular dichroism is a promising candidate for chiral sensors.The combination of experimental and theoretical studies on these helical structures might provide insights into the design of helically chiral small-molecule-based sensors or emitters.展开更多
Chiroptical properties including electronic circular dichroism(ECD) and optical rotatory dispersion(ORD) of artemisinin and artemether have been fully studied using quantum-chemical calculation based on time-depen...Chiroptical properties including electronic circular dichroism(ECD) and optical rotatory dispersion(ORD) of artemisinin and artemether have been fully studied using quantum-chemical calculation based on time-dependent density functional theory.Both theoretical ECD and ORD of these two compounds were in good match with the experimental data.ECD spectrum of artemether could be totally attributed to the peroxide group,and that of artemisinin was an overlay of contribution from δ-lactone and peroxide moieties,which leading to a positive maximum at 260 nm.Our results showed that peroxide group could produce a broad ECD band in the far-UV region originated from electron transitions of HOMO →LUMO,HOMO-1 →LUMO and HOMO-2 →LUMO in the case of artemether.This work provided a theoretical interpretation of the ECD behavior of peroxide bond.展开更多
Reported here is fabrication of optically active micelles with broad range of morphologies in water, such as spheres, cylinders, and vesicles, from self-assembly of poly(ethylene glycol) monomethyl ether-b-poly- (m...Reported here is fabrication of optically active micelles with broad range of morphologies in water, such as spheres, cylinders, and vesicles, from self-assembly of poly(ethylene glycol) monomethyl ether-b-poly- (methacryloyl-L-leucine methyl ester) (MPEG-b-PMALM) copolymer, which was prepared via atom transfer radical polymerization (ATRP) from vinyl monomer bearing chiral amino acid moieties, N-methacryloyl L-leucine methyl ester (MALM), using bromine (Br) end-capped poly(ethylene golycol) monomethylether (MPEG-Br) as macroinitiator in the presence of CuBr/Me6TREN as catalytic system.展开更多
Unraveling the key structural features to maximize the chiroptical properties is of significance for developing high-performance chiral materials.Here we present our first attempt to elucidate and understand the molec...Unraveling the key structural features to maximize the chiroptical properties is of significance for developing high-performance chiral materials.Here we present our first attempt to elucidate and understand the molecular design of excellent chiroptical properties via the combination of multiplicity and the alignment of subhelicenes.Two stereoisomeric PDI-bladed quintuple[6]helicenes,namely D_(5)-CRP and C_(2)-CRP,were revealed to show distinct spatial arrangements of subhelicenes.Circular dichroism(CD)spectra showed that the Cotton effects(Δε)are reaching 1,412 mol-1L cm-1for D_(5)-CRP and 669 mol^(-1)L cm^(-1)for C_(2)-CRP in the visible spectrum.The greatly amplifiedΔεrelative to the smaller analogue NPDH arises from the circular annulation of helicenes and high molecular symmetry that could significantly regulate the transition dipole moments and thereby make them tend to be(anti)parallel,as supported by TDDFT calculations for the rotatory strength(R).Consequently,the maximal dissymmetry factors(|g_(abs)|and|g_(lum)|)of this kind of chiral molecular carbon imides were estimated to be up to 0.021 and 0.012,respectively.This study provides a deep insight into the chiroptical properties of complicated chiral systems.展开更多
Benzimidazole amino acid derivatives behave as supramolecular hosts to include organic acids via complementary hydrogen bonding whereby supramolecular chirality and chiroptical properties could be manipulated.Organic ...Benzimidazole amino acid derivatives behave as supramolecular hosts to include organic acids via complementary hydrogen bonding whereby supramolecular chirality and chiroptical properties could be manipulated.Organic acids enhanced the chiral assembly that showed tunable circularly polarized luminescence with high dissymmetry g-factors at 10^(-2)grade.展开更多
Two diastereoisomers(NTPH-P and NTPH-T1) as a C2-symmetric triple [5]helicene based on N-annulated triperylene hexaimide were synthesized.Aided by nuclear magnetic resonance spectroscopy(NMR) and theoretical calculati...Two diastereoisomers(NTPH-P and NTPH-T1) as a C2-symmetric triple [5]helicene based on N-annulated triperylene hexaimide were synthesized.Aided by nuclear magnetic resonance spectroscopy(NMR) and theoretical calculations,NTPH-P was assigned to three-blade propeller conformation while NTPH-T1 tended to exhibit twisted conformation with pyrrole ring fusing on a bowl-shaped PDI foil.Characterized by circular dichroism(CD) and circular polarized luminescence(CPL) measurements,the enantiomerically pure NTPH-P exhibited fairly good chiral activities both in the absorption and emission range with dissymmetry factors |gabs| of 4.1×10^-3 and |glum| of 1.2×10^-3.The diastereoisomers were further employed as acceptors for organic solar cells with distinct PCEs of 8.11% and 5.24% for NTPH-P and NTPH-T1 based devices,respectively,signifying the prospects in chiroptical electronics by designing molecularly defined aromatics.展开更多
hydrocarbon belts due to their potential applications in carbon nanotechnology.By contrast,heteroatomembedded zigzag hydrocarbon belts as advanced design strategies with fascinating structures and desirable,unique pro...hydrocarbon belts due to their potential applications in carbon nanotechnology.By contrast,heteroatomembedded zigzag hydrocarbon belts as advanced design strategies with fascinating structures and desirable,unique properties have remained largely unexplored,and inherently chiral ones are unknown.Herein,we report the synthesis of a diversity of symmetric and highly enantiopure inherently chiral O-and N-doped zigzag-type hydrocarbon belts starting from strainless macrocycles based on fjord-stitching strategy.The readily available pertriflated resorcin[6]arene underwent partial hydrolyses and intramolecular S_(N)Ar reactions to form a calix[3](9H-xanthene)derivative and a prochiral half-belt selectively.Straightforward transformations of calix[3](9H-xanthene)into C_(3v)-symmetric molecular belts were achieved by closing the rest of the fjords with triple intramolecular S_(N)Ar reactions and Yamamoto homo coupling reactions,as well as palladiumcatalyzed intermolecular acridination reactions with primary amines.The prochiral half-belt underwent enantioselective desymmetrizative mono-acridination to afford an inherently chiral N,O_(4)-bridged pseudo-belt with an enantiomeric excess(ee)value of>99%under the catalysis of Pd(OAc)_(2)and(R)-Antphos.Ring closure reactions of the pseudo-belt produced diverse heteroatom-inlayed zigzag-type hydrocarbon belts of inherent chirality.Further,we showed the unique cavity structures of the belts and demonstrated interesting chiroptic properties of the inherently enantiopure chiral belts.This research opens the door for the exploration of novel and sophisticated symmetric and inherently chiral molecular nanobelt structures with outstanding physical and chemical properties,as well as potential applications.展开更多
Circularly polarized luminescence(CPL)is the emission featured spatial orientation equivalent to circular dichroism.Owning to the unique magnetic dipole-allowed but electric-dipole-forbidden 4f→4f transitions,chiral ...Circularly polarized luminescence(CPL)is the emission featured spatial orientation equivalent to circular dichroism.Owning to the unique magnetic dipole-allowed but electric-dipole-forbidden 4f→4f transitions,chiral lanthanide complexes have been recognized as ideal candidates to achieve unprecedented luminescence dissymmetry factor(glum).Their inherent electric-dipole-forbidden transition can be partly allowed,through the rational design of coordination ligands to lower the surrounding symmetry,further endowing them with relatively high quantum yields(QYs).Moreover,the blossom of supramolecular chemistry in lanthanide complexes allows for the construction of discrete oligomers and hierarchical assemblies,rendering them with enhanced chiroptical activities.Here,we deploy this review by summarizing recent advances in the chiroptical properties of lanthanide complexes,spanning multiple scales from isolated mononuclear individuals,discrete polynuclear oligomers,to infinite hierarchical assemblies.We first introduce the basic concept and several important parameters for the assessment of CPL activity.Then,isolated mononuclear lanthanide complexes coordinated with different types of antennas,along with the unique chirality transfer and induction in achiral lanthanide complexes were discussed.Next,the systematical discussion on chiroptical properties in discrete polynuclear lanthanide oligomers and infinite hierarchical lanthanide assemblies was presented.Meanwhile,the state-of-the-art applications of CPL-active lanthanide complexes were revisited.We end up this review with the conclusion and prospects,involving the rational design of ligands,directed and hierarchically precise self-assembly,and extending applications of chiral lanthanide complexes.展开更多
The paper addresses the creation of circular optical properties from a femtosecond laser light beam with a linear polarization in an achiral material(glass)under an orthogonal incidence.In this situation,all aspects o...The paper addresses the creation of circular optical properties from a femtosecond laser light beam with a linear polarization in an achiral material(glass)under an orthogonal incidence.In this situation,all aspects of the experiment are achiral and therefore should not give rise to chiral property creation.From that observation,we propose an interpretation that involves the action of a light-induced torque on the matter carrying a light-induced dielectric moment.We found that a direct current(DC)electric field could be produced in the lattice by the femtosecond laser in our conditions and that a non-collinear dielectric moment is created by a nonlinear effect between the DC electric field and the stress field due to the transformation of the material.We reveal that it is possible to break the chiral symmetry of glass using an intense,ultrashort laser light pulse.展开更多
Helix structures at atomic/molecular level have not been found in self-assembled peptide seque nce with less than three residues.Asβ-sheet supramolecular secondary structures have been discovered in solidstate amino ...Helix structures at atomic/molecular level have not been found in self-assembled peptide seque nce with less than three residues.Asβ-sheet supramolecular secondary structures have been discovered in solidstate amino acids,we here report the conjugation of simple N-terminal aryl protecting group could give rise to helical supramolecular secondary structures in solid-state,which determines the optical activities of the adjacent aryl groups.The carboxylic acid-involved asymmetric H-bonds in N-te rminal aryl amino acids induce the emergence of super-helical structures of amino acid residues and aryl groups.In most cases,supramolecular tilted chirality of aryl groups is opposite to that of amino acid sequences,of which handedness and helical pitch are determined by the H-bond modalities.Determining correlation between supramolecular tilted chirality of aryl segments and their chiroptical activities is firstly unveiled,which was verified by the computational results based on density functional theory.Most aryl amino acids self-assembled by nanoprecipitation method via crystallization induced self-assembly into rigid one-dimensional microstructures with ultra-high Young's modulus.This study reveals the generic existence of chiral supramolecular structure s in aggregated amino acid derivatives and gives an in-depth investigation into the structural-property relationships,which could guide the rational design and screening of chiroptical supramolecular materials.展开更多
基金supported by the Hong Kong Research Grants Council(27301720,17304021)National Natural Science Foundation of China(22122114,22122503,21790361).
文摘The precise synthesis of helicenes with topologically defined length and specific heteroatomic perturbation in the screw-like conjugated skeletons plays an emerging role in the manipulation of chiral materials.Facile,selective,and programmable routes to helicenes or heterohelicenes are highly desirable yet challenging for structure-chiroptical property relationship studies.Herein,we report the synthesis and characterization of NBN-doped helicenes with boron atoms in the inner rims,enabled by the highly regioselective one-pot borylation of rationally designed precursors with,namely,fold-in or pan-out manner.The incorporation of nonbonded boron and nitrogen atoms resulted in narrow-band emission and improved optical properties for the single-stranded carbon helix.In addition,numbers and arrangement modes of fused six-membered rings have distinct effects on configurational stability and chiroptical properties,revealing that BN-[6]H with strong circular dichroism is a promising candidate for chiral sensors.The combination of experimental and theoretical studies on these helical structures might provide insights into the design of helically chiral small-molecule-based sensors or emitters.
基金supported by the Fundamental Research Funds for the Central Institutes of China(No.2012ZD03)
文摘Chiroptical properties including electronic circular dichroism(ECD) and optical rotatory dispersion(ORD) of artemisinin and artemether have been fully studied using quantum-chemical calculation based on time-dependent density functional theory.Both theoretical ECD and ORD of these two compounds were in good match with the experimental data.ECD spectrum of artemether could be totally attributed to the peroxide group,and that of artemisinin was an overlay of contribution from δ-lactone and peroxide moieties,which leading to a positive maximum at 260 nm.Our results showed that peroxide group could produce a broad ECD band in the far-UV region originated from electron transitions of HOMO →LUMO,HOMO-1 →LUMO and HOMO-2 →LUMO in the case of artemether.This work provided a theoretical interpretation of the ECD behavior of peroxide bond.
基金support by the National Natural Science Foundation of China(No.20474068)the support from the Outstanding Overseas Chinese Scholars Funds of the Chinese Academy of Sciences.
文摘Reported here is fabrication of optically active micelles with broad range of morphologies in water, such as spheres, cylinders, and vesicles, from self-assembly of poly(ethylene glycol) monomethyl ether-b-poly- (methacryloyl-L-leucine methyl ester) (MPEG-b-PMALM) copolymer, which was prepared via atom transfer radical polymerization (ATRP) from vinyl monomer bearing chiral amino acid moieties, N-methacryloyl L-leucine methyl ester (MALM), using bromine (Br) end-capped poly(ethylene golycol) monomethylether (MPEG-Br) as macroinitiator in the presence of CuBr/Me6TREN as catalytic system.
基金supported by the National Natural Science Foundation of China(22122503,22235005,and 22275112)the Shandong Provincial Natural Science Foundation(ZR2019ZD50)。
文摘Unraveling the key structural features to maximize the chiroptical properties is of significance for developing high-performance chiral materials.Here we present our first attempt to elucidate and understand the molecular design of excellent chiroptical properties via the combination of multiplicity and the alignment of subhelicenes.Two stereoisomeric PDI-bladed quintuple[6]helicenes,namely D_(5)-CRP and C_(2)-CRP,were revealed to show distinct spatial arrangements of subhelicenes.Circular dichroism(CD)spectra showed that the Cotton effects(Δε)are reaching 1,412 mol-1L cm-1for D_(5)-CRP and 669 mol^(-1)L cm^(-1)for C_(2)-CRP in the visible spectrum.The greatly amplifiedΔεrelative to the smaller analogue NPDH arises from the circular annulation of helicenes and high molecular symmetry that could significantly regulate the transition dipole moments and thereby make them tend to be(anti)parallel,as supported by TDDFT calculations for the rotatory strength(R).Consequently,the maximal dissymmetry factors(|g_(abs)|and|g_(lum)|)of this kind of chiral molecular carbon imides were estimated to be up to 0.021 and 0.012,respectively.This study provides a deep insight into the chiroptical properties of complicated chiral systems.
基金supported by the National Natural Science Foundation of China(Nos.21901145,22171165)the financial support from Youth Cross-Scientific Innovation Group of Shandong University(No.2020QNQT003)。
文摘Benzimidazole amino acid derivatives behave as supramolecular hosts to include organic acids via complementary hydrogen bonding whereby supramolecular chirality and chiroptical properties could be manipulated.Organic acids enhanced the chiral assembly that showed tunable circularly polarized luminescence with high dissymmetry g-factors at 10^(-2)grade.
基金supported by the National Natural Science Foundation of China(21790361,21734009)the National Key R&D Program of China(2017YFA0204701)+1 种基金the Youth Innovation Promotion Association of Chinese Academy of Sciences(2017048)DFG within TRR 61
文摘Two diastereoisomers(NTPH-P and NTPH-T1) as a C2-symmetric triple [5]helicene based on N-annulated triperylene hexaimide were synthesized.Aided by nuclear magnetic resonance spectroscopy(NMR) and theoretical calculations,NTPH-P was assigned to three-blade propeller conformation while NTPH-T1 tended to exhibit twisted conformation with pyrrole ring fusing on a bowl-shaped PDI foil.Characterized by circular dichroism(CD) and circular polarized luminescence(CPL) measurements,the enantiomerically pure NTPH-P exhibited fairly good chiral activities both in the absorption and emission range with dissymmetry factors |gabs| of 4.1×10^-3 and |glum| of 1.2×10^-3.The diastereoisomers were further employed as acceptors for organic solar cells with distinct PCEs of 8.11% and 5.24% for NTPH-P and NTPH-T1 based devices,respectively,signifying the prospects in chiroptical electronics by designing molecularly defined aromatics.
基金supported by the National Natural Science Foundation of China(NSFC,grant nos.22050005,21920102001,22171160,and 22371161)Tsinghua University Dushi Program,and China National Postdoctoral Program for Innovative Talents(grant no.BX20220184).
文摘hydrocarbon belts due to their potential applications in carbon nanotechnology.By contrast,heteroatomembedded zigzag hydrocarbon belts as advanced design strategies with fascinating structures and desirable,unique properties have remained largely unexplored,and inherently chiral ones are unknown.Herein,we report the synthesis of a diversity of symmetric and highly enantiopure inherently chiral O-and N-doped zigzag-type hydrocarbon belts starting from strainless macrocycles based on fjord-stitching strategy.The readily available pertriflated resorcin[6]arene underwent partial hydrolyses and intramolecular S_(N)Ar reactions to form a calix[3](9H-xanthene)derivative and a prochiral half-belt selectively.Straightforward transformations of calix[3](9H-xanthene)into C_(3v)-symmetric molecular belts were achieved by closing the rest of the fjords with triple intramolecular S_(N)Ar reactions and Yamamoto homo coupling reactions,as well as palladiumcatalyzed intermolecular acridination reactions with primary amines.The prochiral half-belt underwent enantioselective desymmetrizative mono-acridination to afford an inherently chiral N,O_(4)-bridged pseudo-belt with an enantiomeric excess(ee)value of>99%under the catalysis of Pd(OAc)_(2)and(R)-Antphos.Ring closure reactions of the pseudo-belt produced diverse heteroatom-inlayed zigzag-type hydrocarbon belts of inherent chirality.Further,we showed the unique cavity structures of the belts and demonstrated interesting chiroptic properties of the inherently enantiopure chiral belts.This research opens the door for the exploration of novel and sophisticated symmetric and inherently chiral molecular nanobelt structures with outstanding physical and chemical properties,as well as potential applications.
基金The authors sincerely acknowledge the financial support from the National Natural Science Foundation of China(12174151,61935009,11974142,and U21A2068)the Science and Technology Development Program of Jilin Province(20200401059GX).
文摘Circularly polarized luminescence(CPL)is the emission featured spatial orientation equivalent to circular dichroism.Owning to the unique magnetic dipole-allowed but electric-dipole-forbidden 4f→4f transitions,chiral lanthanide complexes have been recognized as ideal candidates to achieve unprecedented luminescence dissymmetry factor(glum).Their inherent electric-dipole-forbidden transition can be partly allowed,through the rational design of coordination ligands to lower the surrounding symmetry,further endowing them with relatively high quantum yields(QYs).Moreover,the blossom of supramolecular chemistry in lanthanide complexes allows for the construction of discrete oligomers and hierarchical assemblies,rendering them with enhanced chiroptical activities.Here,we deploy this review by summarizing recent advances in the chiroptical properties of lanthanide complexes,spanning multiple scales from isolated mononuclear individuals,discrete polynuclear oligomers,to infinite hierarchical assemblies.We first introduce the basic concept and several important parameters for the assessment of CPL activity.Then,isolated mononuclear lanthanide complexes coordinated with different types of antennas,along with the unique chirality transfer and induction in achiral lanthanide complexes were discussed.Next,the systematical discussion on chiroptical properties in discrete polynuclear lanthanide oligomers and infinite hierarchical lanthanide assemblies was presented.Meanwhile,the state-of-the-art applications of CPL-active lanthanide complexes were revisited.We end up this review with the conclusion and prospects,involving the rational design of ligands,directed and hierarchically precise self-assembly,and extending applications of chiral lanthanide complexes.
基金the support of FP7-PEOPLE-IRSES e-FLAG 247635 from the Agence Nationale pour la Recherche(ANR-09-BLAN-0172-01).
文摘The paper addresses the creation of circular optical properties from a femtosecond laser light beam with a linear polarization in an achiral material(glass)under an orthogonal incidence.In this situation,all aspects of the experiment are achiral and therefore should not give rise to chiral property creation.From that observation,we propose an interpretation that involves the action of a light-induced torque on the matter carrying a light-induced dielectric moment.We found that a direct current(DC)electric field could be produced in the lattice by the femtosecond laser in our conditions and that a non-collinear dielectric moment is created by a nonlinear effect between the DC electric field and the stress field due to the transformation of the material.We reveal that it is possible to break the chiral symmetry of glass using an intense,ultrashort laser light pulse.
基金supported by the Qilu Young Scholarship Funding of Shandong Universitysupported by the National Natural Science Foundation of China(Nos.21872087,21901145)Natural Science Foundation of Jiangsu Province(No.BK20190209)the financial support from Youth cross-scientific innovation group of Shandong University(No.2020QNQT003)。
文摘Helix structures at atomic/molecular level have not been found in self-assembled peptide seque nce with less than three residues.Asβ-sheet supramolecular secondary structures have been discovered in solidstate amino acids,we here report the conjugation of simple N-terminal aryl protecting group could give rise to helical supramolecular secondary structures in solid-state,which determines the optical activities of the adjacent aryl groups.The carboxylic acid-involved asymmetric H-bonds in N-te rminal aryl amino acids induce the emergence of super-helical structures of amino acid residues and aryl groups.In most cases,supramolecular tilted chirality of aryl groups is opposite to that of amino acid sequences,of which handedness and helical pitch are determined by the H-bond modalities.Determining correlation between supramolecular tilted chirality of aryl segments and their chiroptical activities is firstly unveiled,which was verified by the computational results based on density functional theory.Most aryl amino acids self-assembled by nanoprecipitation method via crystallization induced self-assembly into rigid one-dimensional microstructures with ultra-high Young's modulus.This study reveals the generic existence of chiral supramolecular structure s in aggregated amino acid derivatives and gives an in-depth investigation into the structural-property relationships,which could guide the rational design and screening of chiroptical supramolecular materials.