Ring Size-Dependent Solution Behavior of Macrocycles: Dipole–Dipole Attraction Counteracted by Excluded Volume Repulsion

2021 ◽  
Author(s):  
Jing Kang ◽  
Junli Zhu ◽  
Jiaping Lin ◽  
Chenglong Han ◽  
Kun Liu ◽  
...  
1988 ◽  
Vol 53 (4) ◽  
pp. 893-894 ◽  
Author(s):  
Constantinos G. Screttas ◽  
Ioulia C. Smonou
Keyword(s):  

2019 ◽  
Author(s):  
Martin Peeks ◽  
Juliane Gong ◽  
Kirstie McLoughlin ◽  
Takayuki Kobatake ◽  
Renee Haver ◽  
...  

Aromaticity can be a useful concept for predicting the behavior of excited states. Here we show that π-conjugated porphyrin nanorings exhibit size-dependent excited-state global aromaticity and antiaromaticity, for rings containing up to eight porphyrin subunits, although they have no significant global aromaticity in their neutral singlet ground states. Applying Baird’s law, odd rings ([4n] π-electrons) are aromatic in their excited states, whereas the excited states of even rings ([4n+2] π-electrons) are antiaromatic. These predictions are borne out by density functional theory (DFT) studies of the nucleus-independent chemical shift in the T1 triplet state of each ring, which reveal the critical importance of the triplet delocalization to the emergence of excited-state aromaticity. The singlet excited states (S1) are explored by measurements of the radiative rate and fluorescence peak wavelength, revealing a subtle odd-even alternation as a function of ring size, consistent with symmetry-breaking in antiaromatic excited states.


2019 ◽  
Vol 55 (19) ◽  
pp. 2749-2752 ◽  
Author(s):  
Yuki Nojima ◽  
Masashi Hasegawa ◽  
Nobuyuki Hara ◽  
Yoshitane Imai ◽  
Yasuhiro Mazaki

A series of cyclic oligomers with Dn symmetry (n = 2–5) based on chiral (R)/(S)-binaphthyl exhibiting intensive chiroptical properties were synthesized by using a Ni(0)-catalyzed coupling reaction.


2018 ◽  
Vol 8 (32) ◽  
pp. 1802175 ◽  
Author(s):  
Shu-Mao Xu ◽  
Ying-Chun Ding ◽  
Xin Liu ◽  
Qiang Zhang ◽  
Kai-Xue Wang ◽  
...  

2018 ◽  
Vol 20 (6) ◽  
pp. 4167-4180 ◽  
Author(s):  
Anuja Singh ◽  
Avik Kumar Pati ◽  
Ashok Kumar Mishra

Photophysical understanding of organic fluorophores with π-conjugated scaffolds is crucial as such dyes are central to optoelectronic applications.


2019 ◽  
Author(s):  
Martin Peeks ◽  
Juliane Gong ◽  
Kirstie McLoughlin ◽  
Takayuki Kobatake ◽  
Renee Haver ◽  
...  

Aromaticity can be a useful concept for predicting the behavior of excited states. Here we show that π-conjugated porphyrin nanorings exhibit size-dependent excited-state global aromaticity and antiaromaticity, for rings containing up to eight porphyrin subunits, although they have no significant global aromaticity in their neutral singlet ground states. Applying Baird’s law, odd rings ([4n] π-electrons) are aromatic in their excited states, whereas the excited states of even rings ([4n+2] π-electrons) are antiaromatic. These predictions are borne out by density functional theory (DFT) studies of the nucleus-independent chemical shift in the T1 triplet state of each ring, which reveal the critical importance of the triplet delocalization to the emergence of excited-state aromaticity. The singlet excited states (S1) are explored by measurements of the radiative rate and fluorescence peak wavelength, revealing a subtle odd-even alternation as a function of ring size, consistent with symmetry-breaking in antiaromatic excited states.


2000 ◽  
Vol 73 (7) ◽  
pp. 1557-1565 ◽  
Author(s):  
Masanobu Kojima ◽  
Akito Ishida ◽  
Yasunao Kuriyama ◽  
Shigero Oishi

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