Aggregation-induced chirality amplification of optically active fluorescent polyurethane and a cyclic dimer in the ground and excited states

Song, Zhiyi; Sato, Hiroyasu; Pietropaolo, Adriana; Wang, Qingyu; Shimoda, Shuhei; Dai, Heshuang; Imai, Yoshitane; Toda, Hayato; Harada, Takunori; Shichibu, Yukatsu; Konishi, Katsuaki; Bando, Masayoshi; Naga, Naofumi

doi:10.1039/d1cc05633f

Cited by 11 publications

(3 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This may be reasonable because axial chirality around single bonds connecting aromatic groups has been reported to be significantly affected on photoexcitation. A twisted aromatic–aromatic junction in the ground state can be transformed to a coplanar conformation in excited states (twisted–coplanar transition, TCT). − TCT may not simply cause racemization but may change the conformation of an entire chain for the polymers studied in this work, which have various aromatic–aromatic junctions.…”

Section: Discussionmentioning

confidence: 99%

Optically Active Poly(benzene-1,4-diyl)s with Random and Alternating Copolymer Sequences Composed of Chiral and Achiral, Bulky Monomeric Units: A Systematic Study on Side-Chain Bulkiness Effects on Ground-State and Excited-State Chiroptical Properties and Chiral Recognition Ability

et al. 2022

Self Cite

View full text Add to dashboard Cite

Random copolymers comprising chiral and achiral benzene-14,-diyl units were prepared by Ni-mediated copolymerization of optically active 1,4-dibromo-2,5-bis((S)-2-methylbutoxy)benzene with bulky, achiral monomers, i.e., 1,4-dibromo-2,5diphenylbenzene, 1,4-dibromo-2,5-bis(3,5-dimethylphenyl)benzene, 1,4-dibromo-2,5-bis(3,5-bis(trifluoromethyl)phenyl)benzene, and 1,4-dibromo-2,5-bis(3,5-diphenylphenyl)-benzene, and the corresponding alternating copolymers were synthesized by Pd-catalyzed Suzuki−Miyaura cross-coupling of optically active 1,4-bis-(dihydroxyboranyl)-2,5-bis((S)-2-methyl-butoxy)benzene with bulky, achiral monomers. Poly(benzene-1,4-diyl)s with achiral 3,5-disubstituted or unsubstituted phenyl groups and chiral (S)-2-methylbutoxy groups in the side chain were thus obtained. The copolymers showed circular dichroism (CD) spectra whose shapes and intensities largely varied depending on the state of the sample (solution or suspension or film) and the chemical structure. In suspensions and films, both the random and alternating polymers with side-chain 3,5-disubstituted phenyl groups showed intense CD spectra suggestive of a chiral conformation such as preferred-handed helices, while they indicated only moderate CD intensities in solution. Both the random and alternating copolymers with side-chain 3,5disubstituted phenyl groups led to higher anisotropy (g CD ) values than those with side-chain phenyl groups, indicating that sidechain bulkiness plays a role in creating a bias on the population of one enantiomeric structure in the solid state. Among the three 3,5disubstituted phenyl groups, the 3,5-dimethylphenyl group, which is not seemingly the bulkiest one, tended to result in the greatest g CD values. On the other hand, the side-chain 3,5-bis(trifluoromethyl)phenyl group and unsubstituted phenyl groups led to the greatest anisotropy (g lum ) values in circularly polarized light (CPL) emission properties in films for the random and alternating copolymers, indicating that the significance of bulkiness of side-chain groups varies between the ground state and excited states. The alternating copolymer with the side-chain 3,5-bis(trifluoromethyl)phenyl group showed a g lum of +0.012, which arises from the strong electron-withdrawing effects of the −CF 3 group. CPL emission was more significant for the random copolymers than for the alternating copolymers. Some of the polymers exhibited chiral recognition abilities toward trans-stilbene oxide, Troger's base, and flavanone, where resolution performance varied depending on the solvent and polymer structure, and the order of separation factors was not particularly in agreement with the order of g CD values in CD spectra in spite of the fact that CD is often generally used to quantify the chirality of materials.

show abstract

Section: Discussionmentioning

confidence: 99%

Optically Active Poly(benzene-1,4-diyl)s with Random and Alternating Copolymer Sequences Composed of Chiral and Achiral, Bulky Monomeric Units: A Systematic Study on Side-Chain Bulkiness Effects on Ground-State and Excited-State Chiroptical Properties and Chiral Recognition Ability

et al. 2022

Self Cite

View full text Add to dashboard Cite

show abstract

“…32,33,44 Similar enhancement of CD by aggregation (AICD) was also reported in other systems. 50,51 When the water fraction in the THF/water mixture was changed to 90%, a further increase was observed in the TPE-derived peak at 280-350 nm (Fig. S14 and S15 †), suggesting that the transformation of the APhePheTPE-assembled structures into helical nanoribbons is related to the AICD property.…”

Section: Polymer Chemistry Papermentioning

confidence: 99%

Synthesis and self-assembly of a diphenylalanine–tetraphenylethylene hybrid monomer and RAFT polymers with aggregation-induced emission

Yonenuma

Mori

2023

Polym. Chem.

View full text Add to dashboard Cite

show abstract

“…[1][2][3] In many cases, highly rigid and ordered chiral structures resulted in high anisotropy factor (g lum ) (g lum = 2(I L À I R )/(I L + I R ), where I L and I R are the intensities of left-handed and right-handed CPL): noticeable examples include helicenes and their derivatives [4][5][6][7] and systems with intermolecular ordering. 8,9 In sharp contrast, even unregulated, amorphous polymers and those combined with small molecules have been reported to lead to highly efficient CPLm. 10,11 However, the exact reasons for the efficient CPLm have not been unambiguously presented in the literature.…”

mentioning

confidence: 99%

Molecular ordering-enhanced circularly polarized luminescence of chiral 1,10-phenanthroline derivatives

Bando,

Fortino,

Pietropaolo

et al. 2024

Chem. Commun.

Self Cite

View full text Add to dashboard Cite

show abstract

Aggregation-induced chirality amplification of optically active fluorescent polyurethane and a cyclic dimer in the ground and excited states

Abstract: Optically active linear polyurethane and cyclic dimer were synthesized from 2,7-diisocyanatofluorene and 2,2’-dihydroxy-1,1’-binaphthyl. Circular dichroism (CD) spectral intensity of polymer was amplified at a higher concentration through aggregate formation while...

Cited by 11 publications

References 32 publications

Optically Active Poly(benzene-1,4-diyl)s with Random and Alternating Copolymer Sequences Composed of Chiral and Achiral, Bulky Monomeric Units: A Systematic Study on Side-Chain Bulkiness Effects on Ground-State and Excited-State Chiroptical Properties and Chiral Recognition Ability

Optically Active Poly(benzene-1,4-diyl)s with Random and Alternating Copolymer Sequences Composed of Chiral and Achiral, Bulky Monomeric Units: A Systematic Study on Side-Chain Bulkiness Effects on Ground-State and Excited-State Chiroptical Properties and Chiral Recognition Ability

Synthesis and self-assembly of a diphenylalanine–tetraphenylethylene hybrid monomer and RAFT polymers with aggregation-induced emission

Molecular ordering-enhanced circularly polarized luminescence of chiral 1,10-phenanthroline derivatives

Contact Info

Product

Resources

About