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
Dipolar interactions are ever‐present in supramolecular architectures, though their impact is typically revealed by making dipoles stronger. While it is also possible to assess the role of dipoles by altering their orientations by using synthetic design, doing so without altering the molecular shape is not straightforward. We have now done this by flipping one triazole unit in a rigid macrocycle, tricarb. The macrocycle is composed of three carbazoles (2 Debye) and three triazoles (5 Debye) defining an array of dipoles aligned radially but organized alternately in and out. These dipoles are believed to dictate edge‐to‐edge tiling and face‐to‐face stacking. We modified our synthesis to prepare isosteric macrocycles with the orientation of one triazole dipole rotated 40°. The new dipole orientation guides edge‐to‐edge contacts to reorder the stability of two surface‐bound 2D polymorphs. The impact on dipole‐enhanced π stacking, however, was unexpected. Our stacking model identified an unchanged set of short‐range (3.4 Å)
- NSF-PAR ID:
- 10480777
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Chemistry – A European Journal
- Volume:
- 30
- Issue:
- 8
- ISSN:
- 0947-6539
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract 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
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