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  • A New Platform of B/N‐Doped Cyclophanes: Access to a π‐Conjugated Block‐Type B 3 N 3 Macrocycle with Strong Dipole Moment and Unique Optoelectronic Properties
Title: A New Platform of B/N‐Doped Cyclophanes: Access to a π‐Conjugated Block‐Type B 3 N 3 Macrocycle with Strong Dipole Moment and Unique Optoelectronic Properties
We herein describe a new design principle to achieve B/N-doped cyclophane where an electron-donor block of three triarylamines (Ar3N) and an acceptor block of three triarylboranes (Ar3B) are spatially separated on opposite sides of the π-extended ring system. DFT computations revealed the distinct electronic structure of the block-type macrocycle MC-b-B3N3 with a greatly enhanced dipole moment and reduced HOMO–LUMO energy gap in comparison to its analogue with alternating B and N sites, MC-alt- B3N3. The unique arrangement of borane acceptor Ar3B and amine donor Ar3N components in MC-b-B3N3 induces exceptionally strong intramolecular charge transfer in the excited state, which is reflected in a largely red-shifted luminescence at 612 nm in solution. The respective linear open-chain oligomer L-b-B3N3 was also synthesized for comparison. Our new approach to donor–acceptor macrocycles offers important fundamental insights and opens up a new avenue to unique optoelectronic materials.  more » « less
Award ID(s):
1954122
PAR ID:
10319886
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Angewandte Chemie International Edition
ISSN:
1433-7851
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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