Double π‐Extended Undecabenzo[7]helicene

Chen, Ying; Lin, Chaojun; Luo, Zhixing; Yin, Zhibo; Shi, Haonan; Zhu, Yanpeng; Wang, Jiaobing

doi:10.1002/ange.202014621

Cited by 27 publications

(15 citation statements)

References 78 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Chiral NGs with absorbance and emission across the visible light region have thus been reported as potential chiroptical materials, [13a, 16, 19] and significant efforts have been recently devoted to realizing chiral NGs with near‐infrared (NIR) optical properties. The extension of the effective π‐conjugation length of helical frameworks and the fusion of multiple helicenes to a large NG core can decrease the energy gap, enabling chiroptical responses in the NIR spectral range, but reported examples of such chiral NGs with NIR optical properties are still rare [18d, 20] …”

Section: Figurementioning

confidence: 99%

Synthesis of Bioctacene‐Incorporated Nanographene with Near‐Infrared Chiroptical Properties

Muñoz‐Mármol

Vasylevskyi

et al. 2023

Angew Chem Int Ed

View full text Add to dashboard Cite

We report the synthesis of a hexabenzoperihexacene (HBPH) with two incorporated octacene substructures, which was unambiguously characterized by single‐crystal X‐ray analysis. The theoretical isomerization barrier of the (P,P)‐/(P,M)‐forms was estimated to be 38.4 kcal mol−1, and resolution was achieved by chiral HPLC. Notably, the enantiomers exhibited opposite circular dichroism responses up to the near‐infrared (NIR) region (830 nm) with a high gabs value of 0.017 at 616 nm. Moreover, HBPH demonstrated NIR emission with a maximum at 798 nm and an absolute PLQY of 41 %. The excited‐state photophysical properties of HBPH were investigated by ultrafast transient absorption spectroscopy, revealing an intriguing feature that was attributed to the rotational and/or conformational dynamics of HBPH after excitation. These results provide new insight into the design of chiral nanographene with NIR optical properties for potential chiroptical applications.

show abstract

Section: Figurementioning

confidence: 99%

Synthesis of Bioctacene‐Incorporated Nanographene with Near‐Infrared Chiroptical Properties

Muñoz‐Mármol

Vasylevskyi

et al. 2023

Angew Chem Int Ed

View full text Add to dashboard Cite

show abstract

“…In recent years, enlarging the π-conjugated plane of helicenes and fusing multiple helicenes into a PAH core have led to a variety of elegant molecules that extend chiroptical responses to the visible spectral range. [12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29] Nevertheless, the absorption dissymmetry factors (gabs) are generally in the range of 10 -4 ~ 10 -3 , 30 with only very few compounds showing gabs on the order of 10 -2 . [12][13][14][15][16][17] Therefore, it is highly demanding to develop novel helicene materials with high gabs in the visible range for future chiral optoelectronic applications.…”

Section: Main Textmentioning

confidence: 99%

B,N-Embedded Double Hetero[7]helicenes with Strong Chiroptical Responses in the Visible Light Region

Chen

Guo

et al. 2021

Preprint

View full text Add to dashboard Cite

The development of helicene molecules with significant chiroptical responses covering a broad range of the visible spectrum is highly desirable for chiral optoelectronic applications; however, their absorption dissymmetry factors (gabs) have been mostly lower than 0.01. In this work, we report unprecedented B,Nembedded double hetero[7]helicenes with nonbonded B and N atoms, which exhibit excellent chiroptical properties, such as strong chiroptical activities from 300 to 700 nm, record high gabs up to 0.033 in the visible spectral range, and tunable circularly polarized luminescence (CPL) from red to near-infrared regions (600 ~ 800 nm) with high photoluminescence quantum yields (PLQYs) up to 100%. As revealed by theoretical analyses, the high gabs values are related to the separate molecular orbital distributions owing to the incorporation of nonbonded B and N atoms. The new type of B,N-embedded double heterohelicenes opens up an appealing avenue to the future exploitation of high-performance chiroptical materials.

show abstract

“…Campaña reported in the same year a hexa- peri -hexabenzocoronene-based π-extended [7]helicene (C 114 H 30 (CO) 2 ( t Bu) 8 ) that is a undecabenzo[7]superhelicenes derivative with two carbonyl group embedded at the ends 19 . Wang reported the synthesis of undecabenzo[7]superhelicenes (C 114 H 26 ( t Bu) 12 ) without carbonyl group in 2021 20 . Although various π-extended HPAHs have been synthesized, the HPAHs reported so far share a common feature that the absorption edge ( λ edge ) does not exceed 650 nm (1.91 eV) despite their relatively large molecular structures, suggesting that increasing the effective conjugation length (ECL) of HPAHs with distorted molecular structures is a challenging issue.…”

Section: Introductionmentioning

confidence: 99%

Doubly linked chiral phenanthrene oligomers for homogeneously π-extended helicenes with large effective conjugation length

et al. 2022

View full text Add to dashboard Cite

Helically twisted conductive nanocarbon materials are applicable to optoelectronic and electromagnetic molecular devices working on the nanometer scale. Herein, we report the synthesis of per-peri-perbenzo[5]- and [9]helicenes in addition to previously reported π-extended [7]helicene. The homogeneously π-extended helicenes can be regarded as helically fused oligo-phenanthrenes. The HOMO−LUMO gap decreased significantly from 2.14 to 1.15 eV with increasing helical length, suggesting the large effective conjugation length (ECL) of the π-extended helical framework. The large ECL of π-extended helicenes is attributed to the large orbital interactions between the phenanthrene subunits at the 9- and 10-positions, which form a polyene-like electronic structure. Based on the experimental results and DFT calculations, the ultrafast decay dynamics on the sub-picosecond timescale were attributed to the low-lying conical intersection.

show abstract

Double π‐Extended Undecabenzo[7]helicene

Cited by 27 publications

References 78 publications

Synthesis of Bioctacene‐Incorporated Nanographene with Near‐Infrared Chiroptical Properties

Synthesis of Bioctacene‐Incorporated Nanographene with Near‐Infrared Chiroptical Properties

B,N-Embedded Double Hetero[7]helicenes with Strong Chiroptical Responses in the Visible Light Region

Doubly linked chiral phenanthrene oligomers for homogeneously π-extended helicenes with large effective conjugation length

Contact Info

Product

Resources

About