Chiroptical responses of chiral plasmonic nanoparticles are influenced by their morphology, yet the impact of supporting substrates is significant but not fully understood. In this study, we numerically investigate th...Chiroptical responses of chiral plasmonic nanoparticles are influenced by their morphology, yet the impact of supporting substrates is significant but not fully understood. In this study, we numerically investigate the effect of high-refractive-index dielectric substrates on the chiroptical response of individual chiral plasmonic nanoparticles. Using Au helicoid as an example, we observe that as the refractive index of the supporting substrate increases, there is a remarkable enhancement in the dissymmetry factor(g-factor), along with an abnormal peak separation between the absorption and scattering g-factor spectra, which is different from typical observations. This unique chiroptical evolution is attributed to the strong plasmon hybridization under circularly polarized in-plane excitation. To validate the universality of these findings, we vary the size and material of the helicoid, confirming the consistent occurrence of this phenomenon. Our findings provide valuable insights into the substrate effect of chiral plasmonic nanoparticles to facilitate their applications in on-chip devices and sensing technologies.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
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
Chiroptical materials are widely used in photonic devices,enantioselective catalysis and bio-sensors.Cellulose-base chiroptical materials with multilength scale structural hierarchy and unique light manipulation abili...Chiroptical materials are widely used in photonic devices,enantioselective catalysis and bio-sensors.Cellulose-base chiroptical materials with multilength scale structural hierarchy and unique light manipulation ability found in nature provide inspiration for materials design.Cellulose nanocrystals(CNC)display twisted rod morphology and hierarchical chirality.Leveraging the evaporation-induced self-assembly of negatively charged CNC,a broad realm of CNC-based chiroptical materials featuring one-dimensional photonic bandgap and novel chiroptical properties have been developed,which are of scientific and technological significance.Here we presented a brief overview on CNC-based chiroptical materials by evaporation-induced self-assembly,showed energy and chirality transfer in a host-vip environment leading to photonic bandgap modulation of optoelectronic properties,outlined novel chiroptical phenomena and their underlying principles,and demonstrated the application potentials of the CNC-based chiroptical materials.展开更多
Pillar[5]arene-based molecular universal joints(MUJs), bearing fused crown ether subring(MUJ1 and MUJ3) or a ring without ether oxygen atom(MUJ2), were synthesized and enantio–differentiated. Significant chiral inver...Pillar[5]arene-based molecular universal joints(MUJs), bearing fused crown ether subring(MUJ1 and MUJ3) or a ring without ether oxygen atom(MUJ2), were synthesized and enantio–differentiated. Significant chiral inversion was observed for the crown ether-fused MUJs upon the addition of equivalent cations Na+, showing an anisotropy(g) factor of 0.014, while alkyl subring-fused MUJ2 showed no CD inversions. Unprecedentedly, sodium ion triggered rolling-in motion of the subring to the pillar[5]arene cavity was verified, and the synergistic noncovalent interaction of cation-π interactions and C–H···π interactions were responsible for the stabilized self-included conformers. The addition of Me OH or competitive hosts 15-crown-5 ether disassembled the complex of MUJ1 and Na+followed by a rolling-out of the subring, which made the sodium-ion triggered chiroptical switching reversible.展开更多
In this contribution,we utilized surface initiated atom transfer radical polymerization(SI-ATRP)to prepare organicinorganic hybrid core/shell silila nanoparticles(NPs),where silia particles acted as cores and polymeri...In this contribution,we utilized surface initiated atom transfer radical polymerization(SI-ATRP)to prepare organicinorganic hybrid core/shell silila nanoparticles(NPs),where silia particles acted as cores and polymeric shells(PAzoMA*)were attached to silica particles via covalent bond.Subsequently,chiroptical switch was sccessfully constructed on silica NPs surface taking advantage of supramolecular chiral self-assembly of the grafted side chain Azo-containing polymer(PAzoMA*).We found that the supramolecular chirality was highly dependent on the molecular weight of grafted PAzoMA*.Meanwhile,the supramolecular chirality could be regulated using 365 nm UV light iradiation and heating cooling treatment,and a reversible supramolecular chiroptical switch could be repeated for over five cycles on silia NPs surface.Moreover,when heated above the glass transition temperature(T_(g))of PAzoMA",the organic-inorganic hybrid nanoparticles(SiO_(2)@PAzoMA*NPs)still exhibited intense DRCD signals.Interestingly,the supramolecular chirality could be retained in solid film for more than 3 months.To conclude,we have prepared an organic inorganic hybrid core/shell chiral slia nanomaterial with dynamic reversible chirality,thermal stability and chiral storage functions,providing potential applications in dynamic asymmetric catalysis,chiral separation and so on.展开更多
The strong chiroptical effect is highly desirable and has a wide range of applications in biosensing, chiral catalysis,polarization tuning, and chiral photo detection. In this work, we find a simple method to enhance ...The strong chiroptical effect is highly desirable and has a wide range of applications in biosensing, chiral catalysis,polarization tuning, and chiral photo detection. In this work, we find a simple method to enhance the reflection circular dichroism(CDR) by placing the planar anisotropic chiral metamaterials(i.e., Z-shaped PACMs) on the interface of two media(i.e., Z-PCMI) with a large refractive index difference. The maximum reflection CDR from the complex system can reach about 0.840 when the refractive index is set as ntop = 4.0 and nbottom = 1.49, which is approximately three times larger than that of placing the Z-shaped PACMs directly on the substrate(i.e., Z-PCMS). While the minimum reflection CDR is 0.157 when the refractive index is set as ntop = 1.0 and nbottom = 1.49. So we can get a large available range of reflection CDR from -0.840 to -0.157. Meanwhile, the transmission CDT remains unchanged with the refractive index ntop increment. Our in-depth research indicates that the large reflection CDR is derived from the difference of non-conversion components of the planar anisotropic chiral metamaterials’ reflection matrices. In short, we provide a simple and practical method to enhance the chiroptical effect by changing the refractive index difference between two media without having to design a complex chiral structure.展开更多
A new alkylpyrrole derivative,fusariumin A(1),was isolated from the culture broth of the fungus Fusarium sp.The absolute configuration of fuasiumin A has been established as(2'R,3'R)using a combination of RDC(...A new alkylpyrrole derivative,fusariumin A(1),was isolated from the culture broth of the fungus Fusarium sp.The absolute configuration of fuasiumin A has been established as(2'R,3'R)using a combination of RDC(residual dipolar coupling)-based NMR and DFT-supported chiroptical spectroscopy.It is worth to note that in this study without the aid of the RDC analysis,an unambiguous determination of configuration and conformation was not feasible due to the excessive conformational possibilities of this open-chain compound.展开更多
The precise control of stereochemistry in organic π-conjugated chiral foldamers remains a fundamental challenge in synthetic chemistry due to the lack of universal design principles.Herein,we establish a versatile st...The precise control of stereochemistry in organic π-conjugated chiral foldamers remains a fundamental challenge in synthetic chemistry due to the lack of universal design principles.Herein,we establish a versatile strategy through cascade integration using a chiral building block Ⅰ-1 as a stereochemical template.Sequential imide functionalization yields Ⅰ-2,followed by parallel π-layer installation and structural expansion to construct foldamers Ⅱ-1,Ⅱ-2,Ⅲ-1,and Ⅲ-2,featuring naphthalimide bridges that interconnect distinct layers with preserved chirality.X-ray crystallography and electrostatic potential analysis conclusively resolve the layered architecture,multi-chiral elements and absolute configurations of this novel folding system.Frontier molecular orbitals and photophysical studies reveal unique luminescent properties arising from the naphthalimide core.The performance characterization indicates that both PLQY and the dissymmetry factors(g_(abs)/g_(lum))of chiroptical properties exhibit significant dependence on spatial modulation.Racemization kinetics and theoretical simulation show that π-layer incorporation significantly enhances interlayer van der Waals interactions,elevating the racemization Gibbs free energy to 41 kcal/mol for Ⅱ-1,which improvement over reported analogues.This work establishes a rational design platform for π-conjugated chiral foldamers,enabling the construction of configurationally stable,geometrically precise architectures with tailored optical properties.展开更多
Heterometallic 3d-4f clusters represent a promising class of multifunctional molecular materials,driven by the synergistic interactions between d-and f-electrons.Incorporating chirality into these systems further expa...Heterometallic 3d-4f clusters represent a promising class of multifunctional molecular materials,driven by the synergistic interactions between d-and f-electrons.Incorporating chirality into these systems further expands their potential applications,particularly in chiroptical and magneto-optical technologies.Herein,we report the successful synthesis of chiral[Ln_(3)Co_(2)](Ln=Er and Y)clusters using binaphthol-based ligands.Single-crystal X-ray diffraction reveals the coexistence of two distinct Co^(2+)coordination geometries:six-coordinate octahedron and five-coordinate trigonal bipyramid.Spectroscopic analyses demonstrate geometry-dependent chiroptical behavior:pentacoordinate Co^(2+)ions predominantly contribute to the circular dichroism(CD)features,while both geometries exhibit distinguishable signals in the magnetic circular dichroism(MCD)spectra.Notably,a pronounced magnetic dipole transition(^(4)I_(15/2)→^(4)I_(13/2))from Er^(3+)centers is observed in the near-infrared MCD region,displaying a high g-factor of 0.0078 T-1.This work highlights the configuration-and ligand field-dependent chiroptical responses in 3d-4f systems,providing new insights for the rational design of advanced magneto-optical devices.展开更多
While extensive research has explored manipulating supramolecular chirality through internal and external factors,the specific solvation effect remains uncharted territory.This study synthesized ortho-functionalized p...While extensive research has explored manipulating supramolecular chirality through internal and external factors,the specific solvation effect remains uncharted territory.This study synthesized ortho-functionalized pillar[5]arene(P[5])derivatives Mn and Dn via thiol-Michael addition,characterizing them through spectroscopic and X-ray single-crystal analyses.Mn and Dn interacted with chiral amines,yielding significant circular dichroism(CD)responses.Intriguingly,the chiral induction exhibited pronounced specific solvation effects,where achiral alcohols either enhanced,attenuated,or reversed CD signals.Testing over 40 alcohols revealed correlations between the specific solvation effects and alcohol polarity and acidity.Molecular dynamics simulations unveiled that the alcohol interacted distinctly through hydrogen bonding,with one ion pair bonding up to four alcohol molecules.The Rp-and Sp-preference of the P[5]core could be altered by the number of bonded alcohols.This work uncovers the critical role of alcohol-specific solvation in ion pair-involved chiral assembly,pertinent for asymmetric ion-pairing catalysis and the use of alcohol additives in organic solvents.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
Plasmonic chiroptical materials,coupled by chirality and surface plasmons,have been attracting great interest due to their potential applications,such as photonics,chiral recognition,asymmetric catalysis and biosensin...Plasmonic chiroptical materials,coupled by chirality and surface plasmons,have been attracting great interest due to their potential applications,such as photonics,chiral recognition,asymmetric catalysis and biosensing.Herein,we constructed a new chiral plasmonic nanostructure—helically grooved gold nanoarrows(HeliGNAs)by introducing L-/Dcysteine(L-/D-Cys)during the growth of the gold nanoarrows(GNAs).The variation of the concentration of L-/D-Cys leads to the HeliGNAs with a tunable plasmonic circular dichroism(PCD).展开更多
Near-infrared(NIR)chiroptical response has been less explored because it is chal-lenging to achieve both chirality and NIR absorption/emission.Herein,we describe the design of heterohelicene-typeβ-isoindigo-based bor...Near-infrared(NIR)chiroptical response has been less explored because it is chal-lenging to achieve both chirality and NIR absorption/emission.Herein,we describe the design of heterohelicene-typeβ-isoindigo-based boron-dipyrromethene(BOD-IPY)analogs(β-IBs),which shift the absorption peak to 800 nm and produce significant Cotton effects(127.8 M-1 cm-1)and absorbance dissymmetry factors(|gabs|3.5=×10-3).The luminescence dissymmetry factor(glum)and circu-larly polarized luminescence(CPL)brightness(BCPL)of up to 1.24×10-3 and 1.78 M-1 cm-1 were realized beyond 800 nm.Theseβ-IBs are thefirst examples of helicene-type compounds with the highest gabs in the NIR region and CPL beyond 800 nm.Theoretical calculations demonstrate that the strong chiroptical activities are triggered by their large transition magnetic dipole moments.This study not only provides a new approach to the synthesis of a larger variety of unprecedented helicene-type BODIPY analogs but also demonstrates excellent NIR chiroptical properties.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
With the development of chiral materials, remarkable progress has been made in the application fields of biology, chemistry, and physics in the past decades. Here we develop a solo-Ag-nanowire(NW)-based, bottom-up chi...With the development of chiral materials, remarkable progress has been made in the application fields of biology, chemistry, and physics in the past decades. Here we develop a solo-Ag-nanowire(NW)-based, bottom-up chiral construction strategy to fabricate a chiral plasmonic film with strong chiroptical activity in the purple-blue band. Finitedifference time-domain simulations predict that helical structures made by Ag NWs with certain interlayer angles possess strong chiroptical intensity. We then apply a Langmuir-Blodgett technique to construct the layered NW assemblies with both handedness via regulating interlayer angle direction. The Ag NW assemblies show the interlayer-angleand film-thickness-dependent circular dichroism, reaching the highest anisotropic factor of 0.03. These new chiral structures will serve as ideal candidates for chiral sensors thanks to their specific plasmonic properties.展开更多
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
The superchiral field that enables ultrasensitive detection and discrimination of chiral matter beyond that of circularly polarized light by its field structure has emerged as a powerful tool in chiroptical spectrosco...The superchiral field that enables ultrasensitive detection and discrimination of chiral matter beyond that of circularly polarized light by its field structure has emerged as a powerful tool in chiroptical spectroscopy,spin photonics,and analytical chemistry.Specially,the superchiral field at the wavelength beyond 15μm is indispensable for various mid-infrared applications,such as ultrasensitive chiroptical sensing in the molecular fingerprint region.Here we propose and present a new strategy to realize the superchiral field with a Kuhn’s dissymmetric factor up to∼90 at the wavelength beyond 15μm.This is enabled by the high-quality(up to∼10^(4))multipole resonance induced by Brillouin-zone-folding-driven quasi-guided mode in a diamond metasurface.This work opens up a new avenue towards realizing mid-infrared superchiral fields at the wavelength beyond 15μm.展开更多
Circularly polarized luminescence(CPL)-active materials have a wide range of technological applications.Traditionally,creating CPL-active materials relies on the use of chiral luminophores.In contrast,supramolecular a...Circularly polarized luminescence(CPL)-active materials have a wide range of technological applications.Traditionally,creating CPL-active materials relies on the use of chiral luminophores.In contrast,supramolecular assembly introduces an innovative and promising strategy for developing CPL-active materials not only from chiral luminophores but also from achiral species.This approach significantly enriches the diversity of CPL-active materials.It also offers an effective means to optimize the performance of CPL-active materials,such as enhancing the asymmetry factor|glum|.Compared to polymers,the assembly of small molecules is generally easier to control.This review systematically summarizes the recent progress and developments in CPL from small-molecule assemblies,particularly focusing on differences,merits,and demerits of three typical assembly modes.The aim is to provide valuable insights for the future development of chiroptical materials.展开更多
Chirality,the property that an object cannot coincide with its mirror image arising from lack of mirror symmetry,is ubiquitous in nature at various length scales.The physical and chemical properties are strongly relat...Chirality,the property that an object cannot coincide with its mirror image arising from lack of mirror symmetry,is ubiquitous in nature at various length scales.The physical and chemical properties are strongly related to the nature of chiral complexes,playing a significant role in various fields such as photonics,biochemistry,medicine and catalysis.In particular,the recent flexible design of chiral metal nanostructures offers one platform for deeply understanding the origin of chirality and one roadmap for the precise construction of chiral nanomaterials directed by the applications.Herein,we summarize the different geometries and classical synthetic approaches to chiral noble metal nanomaterials.Moreover,chiroptical properties and potential applications of chiral metal nanostructures are discussed as well.Finally,the opportunities and challenges toward the synthesis and application of chiral metal nanostructures are proposed.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.62575185 and 62205223)Guangdong Basic and Applied Basic Research Foundation (Grant Nos.2023A1515110091 and 2023A1515011455)+1 种基金Department of Science and Technology of Guangdong Province(Grant Nos.2023QN10C200 and 2023QN10X082)Science and Technology Innovation Commission of Shenzhen (Grant Nos.20231121120748002 and JSGGKQTD20221101115701006)。
文摘Chiroptical responses of chiral plasmonic nanoparticles are influenced by their morphology, yet the impact of supporting substrates is significant but not fully understood. In this study, we numerically investigate the effect of high-refractive-index dielectric substrates on the chiroptical response of individual chiral plasmonic nanoparticles. Using Au helicoid as an example, we observe that as the refractive index of the supporting substrate increases, there is a remarkable enhancement in the dissymmetry factor(g-factor), along with an abnormal peak separation between the absorption and scattering g-factor spectra, which is different from typical observations. This unique chiroptical evolution is attributed to the strong plasmon hybridization under circularly polarized in-plane excitation. To validate the universality of these findings, we vary the size and material of the helicoid, confirming the consistent occurrence of this phenomenon. Our findings provide valuable insights into the substrate effect of chiral plasmonic nanoparticles to facilitate their applications in on-chip devices and sensing technologies.
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 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The authors are grateful for the financial support from NNSF China(grant nos.21975095,21671079,and 21373100)111 project(grant no.B17020),JLU international co-advisorship program(grant no.419020201362)+1 种基金JLU international collaboration program(grant no.45119031C015)the State key laboratory of inorganic synthesis and preparative chemistry of JLU(grant no.1G3194101461).
文摘Chiroptical materials are widely used in photonic devices,enantioselective catalysis and bio-sensors.Cellulose-base chiroptical materials with multilength scale structural hierarchy and unique light manipulation ability found in nature provide inspiration for materials design.Cellulose nanocrystals(CNC)display twisted rod morphology and hierarchical chirality.Leveraging the evaporation-induced self-assembly of negatively charged CNC,a broad realm of CNC-based chiroptical materials featuring one-dimensional photonic bandgap and novel chiroptical properties have been developed,which are of scientific and technological significance.Here we presented a brief overview on CNC-based chiroptical materials by evaporation-induced self-assembly,showed energy and chirality transfer in a host-vip environment leading to photonic bandgap modulation of optoelectronic properties,outlined novel chiroptical phenomena and their underlying principles,and demonstrated the application potentials of the CNC-based chiroptical materials.
基金the support of this work by the National Natural Science Foundation of China (Nos. 22171194, 21971169, 92056116, 21871194)the Science & Technology Department of Sichuan Province (Nos. 2022YFH0095, 2021ZYD0052)。
文摘Pillar[5]arene-based molecular universal joints(MUJs), bearing fused crown ether subring(MUJ1 and MUJ3) or a ring without ether oxygen atom(MUJ2), were synthesized and enantio–differentiated. Significant chiral inversion was observed for the crown ether-fused MUJs upon the addition of equivalent cations Na+, showing an anisotropy(g) factor of 0.014, while alkyl subring-fused MUJ2 showed no CD inversions. Unprecedentedly, sodium ion triggered rolling-in motion of the subring to the pillar[5]arene cavity was verified, and the synergistic noncovalent interaction of cation-π interactions and C–H···π interactions were responsible for the stabilized self-included conformers. The addition of Me OH or competitive hosts 15-crown-5 ether disassembled the complex of MUJ1 and Na+followed by a rolling-out of the subring, which made the sodium-ion triggered chiroptical switching reversible.
基金by the National Natural Science Foundation of China(Nos.21971180 and 92056111)Natural Science Key Basic Research of Jiangsu Province for Higher Education(No.19KJA360006)+2 种基金Postgraduate Research&Practice Innovation Program of Jiangsu Provinee(No.KYCX20_2655)College Students'Innovation and Entrepreneurship Program(No.201910285021Z)the Priority Academic Program Development(PAPD)of Jiangsu Higher Education Institutions and the Program of Innovative Research Team of Soochow University.Prof.W.Zhang thanks Mr.J.Z.Wang in University of Waterloo for English editing.
文摘In this contribution,we utilized surface initiated atom transfer radical polymerization(SI-ATRP)to prepare organicinorganic hybrid core/shell silila nanoparticles(NPs),where silia particles acted as cores and polymeric shells(PAzoMA*)were attached to silica particles via covalent bond.Subsequently,chiroptical switch was sccessfully constructed on silica NPs surface taking advantage of supramolecular chiral self-assembly of the grafted side chain Azo-containing polymer(PAzoMA*).We found that the supramolecular chirality was highly dependent on the molecular weight of grafted PAzoMA*.Meanwhile,the supramolecular chirality could be regulated using 365 nm UV light iradiation and heating cooling treatment,and a reversible supramolecular chiroptical switch could be repeated for over five cycles on silia NPs surface.Moreover,when heated above the glass transition temperature(T_(g))of PAzoMA",the organic-inorganic hybrid nanoparticles(SiO_(2)@PAzoMA*NPs)still exhibited intense DRCD signals.Interestingly,the supramolecular chirality could be retained in solid film for more than 3 months.To conclude,we have prepared an organic inorganic hybrid core/shell chiral slia nanomaterial with dynamic reversible chirality,thermal stability and chiral storage functions,providing potential applications in dynamic asymmetric catalysis,chiral separation and so on.
基金Project supported by the National Natural Science Foundation of China (Grant No. 11604227).
文摘The strong chiroptical effect is highly desirable and has a wide range of applications in biosensing, chiral catalysis,polarization tuning, and chiral photo detection. In this work, we find a simple method to enhance the reflection circular dichroism(CDR) by placing the planar anisotropic chiral metamaterials(i.e., Z-shaped PACMs) on the interface of two media(i.e., Z-PCMI) with a large refractive index difference. The maximum reflection CDR from the complex system can reach about 0.840 when the refractive index is set as ntop = 4.0 and nbottom = 1.49, which is approximately three times larger than that of placing the Z-shaped PACMs directly on the substrate(i.e., Z-PCMS). While the minimum reflection CDR is 0.157 when the refractive index is set as ntop = 1.0 and nbottom = 1.49. So we can get a large available range of reflection CDR from -0.840 to -0.157. Meanwhile, the transmission CDT remains unchanged with the refractive index ntop increment. Our in-depth research indicates that the large reflection CDR is derived from the difference of non-conversion components of the planar anisotropic chiral metamaterials’ reflection matrices. In short, we provide a simple and practical method to enhance the chiroptical effect by changing the refractive index difference between two media without having to design a complex chiral structure.
基金Support by the National Natural Science Foundation of China(U1132607)to J.K.L.the DFG(Forschergruppe FOR 934)to C.Gas well as the Chinese/German foundation(GZ1104)to H.S.and C.G.is acknowledged.
文摘A new alkylpyrrole derivative,fusariumin A(1),was isolated from the culture broth of the fungus Fusarium sp.The absolute configuration of fuasiumin A has been established as(2'R,3'R)using a combination of RDC(residual dipolar coupling)-based NMR and DFT-supported chiroptical spectroscopy.It is worth to note that in this study without the aid of the RDC analysis,an unambiguous determination of configuration and conformation was not feasible due to the excessive conformational possibilities of this open-chain compound.
基金supported by the National Natural Science Foundation of China(22161017,22161016)。
文摘The precise control of stereochemistry in organic π-conjugated chiral foldamers remains a fundamental challenge in synthetic chemistry due to the lack of universal design principles.Herein,we establish a versatile strategy through cascade integration using a chiral building block Ⅰ-1 as a stereochemical template.Sequential imide functionalization yields Ⅰ-2,followed by parallel π-layer installation and structural expansion to construct foldamers Ⅱ-1,Ⅱ-2,Ⅲ-1,and Ⅲ-2,featuring naphthalimide bridges that interconnect distinct layers with preserved chirality.X-ray crystallography and electrostatic potential analysis conclusively resolve the layered architecture,multi-chiral elements and absolute configurations of this novel folding system.Frontier molecular orbitals and photophysical studies reveal unique luminescent properties arising from the naphthalimide core.The performance characterization indicates that both PLQY and the dissymmetry factors(g_(abs)/g_(lum))of chiroptical properties exhibit significant dependence on spatial modulation.Racemization kinetics and theoretical simulation show that π-layer incorporation significantly enhances interlayer van der Waals interactions,elevating the racemization Gibbs free energy to 41 kcal/mol for Ⅱ-1,which improvement over reported analogues.This work establishes a rational design platform for π-conjugated chiral foldamers,enabling the construction of configurationally stable,geometrically precise architectures with tailored optical properties.
基金supported by the National Natural Science Foundation of China(Nos.92461305,92161203 and 92361301).
文摘Heterometallic 3d-4f clusters represent a promising class of multifunctional molecular materials,driven by the synergistic interactions between d-and f-electrons.Incorporating chirality into these systems further expands their potential applications,particularly in chiroptical and magneto-optical technologies.Herein,we report the successful synthesis of chiral[Ln_(3)Co_(2)](Ln=Er and Y)clusters using binaphthol-based ligands.Single-crystal X-ray diffraction reveals the coexistence of two distinct Co^(2+)coordination geometries:six-coordinate octahedron and five-coordinate trigonal bipyramid.Spectroscopic analyses demonstrate geometry-dependent chiroptical behavior:pentacoordinate Co^(2+)ions predominantly contribute to the circular dichroism(CD)features,while both geometries exhibit distinguishable signals in the magnetic circular dichroism(MCD)spectra.Notably,a pronounced magnetic dipole transition(^(4)I_(15/2)→^(4)I_(13/2))from Er^(3+)centers is observed in the near-infrared MCD region,displaying a high g-factor of 0.0078 T-1.This work highlights the configuration-and ligand field-dependent chiroptical responses in 3d-4f systems,providing new insights for the rational design of advanced magneto-optical devices.
基金supported by the National Natural Science Foundation of China(22471182,22271201,92056116,22422108,22171194,22201194)the Fundamental Research Funds for the Central Universities(20826041D4117).
文摘While extensive research has explored manipulating supramolecular chirality through internal and external factors,the specific solvation effect remains uncharted territory.This study synthesized ortho-functionalized pillar[5]arene(P[5])derivatives Mn and Dn via thiol-Michael addition,characterizing them through spectroscopic and X-ray single-crystal analyses.Mn and Dn interacted with chiral amines,yielding significant circular dichroism(CD)responses.Intriguingly,the chiral induction exhibited pronounced specific solvation effects,where achiral alcohols either enhanced,attenuated,or reversed CD signals.Testing over 40 alcohols revealed correlations between the specific solvation effects and alcohol polarity and acidity.Molecular dynamics simulations unveiled that the alcohol interacted distinctly through hydrogen bonding,with one ion pair bonding up to four alcohol molecules.The Rp-and Sp-preference of the P[5]core could be altered by the number of bonded alcohols.This work uncovers the critical role of alcohol-specific solvation in ion pair-involved chiral assembly,pertinent for asymmetric ion-pairing catalysis and the use of alcohol additives in organic solvents.
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(nos.21890734,21972150,21890730,and 21773259)and the Key Research Program of Frontier Sciences,CAS,(no.QYZDJ-SSW-SLH044).
文摘Plasmonic chiroptical materials,coupled by chirality and surface plasmons,have been attracting great interest due to their potential applications,such as photonics,chiral recognition,asymmetric catalysis and biosensing.Herein,we constructed a new chiral plasmonic nanostructure—helically grooved gold nanoarrows(HeliGNAs)by introducing L-/Dcysteine(L-/D-Cys)during the growth of the gold nanoarrows(GNAs).The variation of the concentration of L-/D-Cys leads to the HeliGNAs with a tunable plasmonic circular dichroism(PCD).
基金National Natural Science Foundation of China,Grant/Award Numbers:21871072,22003014Hangzhou Normal University。
文摘Near-infrared(NIR)chiroptical response has been less explored because it is chal-lenging to achieve both chirality and NIR absorption/emission.Herein,we describe the design of heterohelicene-typeβ-isoindigo-based boron-dipyrromethene(BOD-IPY)analogs(β-IBs),which shift the absorption peak to 800 nm and produce significant Cotton effects(127.8 M-1 cm-1)and absorbance dissymmetry factors(|gabs|3.5=×10-3).The luminescence dissymmetry factor(glum)and circu-larly polarized luminescence(CPL)brightness(BCPL)of up to 1.24×10-3 and 1.78 M-1 cm-1 were realized beyond 800 nm.Theseβ-IBs are thefirst examples of helicene-type compounds with the highest gabs in the NIR region and CPL beyond 800 nm.Theoretical calculations demonstrate that the strong chiroptical activities are triggered by their large transition magnetic dipole moments.This study not only provides a new approach to the synthesis of a larger variety of unprecedented helicene-type BODIPY analogs but also demonstrates excellent NIR chiroptical properties.
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 (22071226, 51732011, 21431006, 21761132008, 81788101, 11227901 and 11874164)the Funding of University of Science and Technology of China (KY2060000168 and YD2060002013)+2 种基金the Foundation for Innovative Research Groups of the National Natural Science Foundation of China (21521001)the Key Research Program of Frontier Sciences, CAS (QYZDJ-SSW-SLH036)the Users with Excellence and Scientific Research Grant of Hefei Science Center of CAS (2015HSC-UE007)。
文摘With the development of chiral materials, remarkable progress has been made in the application fields of biology, chemistry, and physics in the past decades. Here we develop a solo-Ag-nanowire(NW)-based, bottom-up chiral construction strategy to fabricate a chiral plasmonic film with strong chiroptical activity in the purple-blue band. Finitedifference time-domain simulations predict that helical structures made by Ag NWs with certain interlayer angles possess strong chiroptical intensity. We then apply a Langmuir-Blodgett technique to construct the layered NW assemblies with both handedness via regulating interlayer angle direction. The Ag NW assemblies show the interlayer-angleand film-thickness-dependent circular dichroism, reaching the highest anisotropic factor of 0.03. These new chiral structures will serve as ideal candidates for chiral sensors thanks to their specific plasmonic properties.
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 National Key R&D Program of China(Grant No.2024YFE0105200)the National Nature Science Foundation of China(Grant No.62405284)。
文摘The superchiral field that enables ultrasensitive detection and discrimination of chiral matter beyond that of circularly polarized light by its field structure has emerged as a powerful tool in chiroptical spectroscopy,spin photonics,and analytical chemistry.Specially,the superchiral field at the wavelength beyond 15μm is indispensable for various mid-infrared applications,such as ultrasensitive chiroptical sensing in the molecular fingerprint region.Here we propose and present a new strategy to realize the superchiral field with a Kuhn’s dissymmetric factor up to∼90 at the wavelength beyond 15μm.This is enabled by the high-quality(up to∼10^(4))multipole resonance induced by Brillouin-zone-folding-driven quasi-guided mode in a diamond metasurface.This work opens up a new avenue towards realizing mid-infrared superchiral fields at the wavelength beyond 15μm.
基金support from the National Natural Science Foundation of China(52473192)。
文摘Circularly polarized luminescence(CPL)-active materials have a wide range of technological applications.Traditionally,creating CPL-active materials relies on the use of chiral luminophores.In contrast,supramolecular assembly introduces an innovative and promising strategy for developing CPL-active materials not only from chiral luminophores but also from achiral species.This approach significantly enriches the diversity of CPL-active materials.It also offers an effective means to optimize the performance of CPL-active materials,such as enhancing the asymmetry factor|glum|.Compared to polymers,the assembly of small molecules is generally easier to control.This review systematically summarizes the recent progress and developments in CPL from small-molecule assemblies,particularly focusing on differences,merits,and demerits of three typical assembly modes.The aim is to provide valuable insights for the future development of chiroptical materials.
基金financially supported by the National Natural Science Foundation of China(Nos.22071172,21902148,12205165,50835002 and 51105102)。
文摘Chirality,the property that an object cannot coincide with its mirror image arising from lack of mirror symmetry,is ubiquitous in nature at various length scales.The physical and chemical properties are strongly related to the nature of chiral complexes,playing a significant role in various fields such as photonics,biochemistry,medicine and catalysis.In particular,the recent flexible design of chiral metal nanostructures offers one platform for deeply understanding the origin of chirality and one roadmap for the precise construction of chiral nanomaterials directed by the applications.Herein,we summarize the different geometries and classical synthetic approaches to chiral noble metal nanomaterials.Moreover,chiroptical properties and potential applications of chiral metal nanostructures are discussed as well.Finally,the opportunities and challenges toward the synthesis and application of chiral metal nanostructures are proposed.