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In the title compound, C10H8N2·2C6H5NO3, 4-nitrophenol and 4,4′-bipyridine crystallized together in a 2:1 ratio in the space groupP21/n. There is a hydrogen-bonding interaction between the nitrogen atoms on the 4,4′-bipyridine molecule and the hydrogen atom on the hydroxyl group on the 4-nitrophenol, resulting in trimolecular units. This structure is a polymorph of a previously reported structure [Nayak & Pedireddi (2016).Cryst. Growth Des.16, 5966–5975], which differs mainly due to a twist in the 4,4′-bipyridine molecule.
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Influence of Amide Connectivity on the Hydrogen‐Bond‐Directed Self‐Assembly of [n.n]Paracyclophanes
Abstract Reported here is the synthesis and self‐assembly characterization of [n.n]paracyclophanes ([n.n]pCps,n=2, 3) equipped with anilide hydrogen bonding units. These molecules differ from previous self‐assembling [n.n]paracyclophanes ([n.n]pCps) in the connectivity of their amide hydrogen bonding units (C‐centered/carboxamide vs.N‐centered/anilide). This subtle change results in a ≈30‐fold increase in the elongation constant for the[2.2]pCp‐4,7,12,15‐tetraanilide ([2.2]pCpNTA) compared to previously reported[2.2]pCp‐4,7,12,15‐tetracarboxamide ([2.2]pCpTA), and a ≈300‐fold increase in the elongation constant for the[3.3]pCp‐5,8,14,17‐tetraanilide ([3.3]pCpNTA) compared to previously reported[3.3]pCp‐5,8,14,17‐tetracarboxamide ([3.3]pCpTA). The[n.n]pCpNTAmonomers also represent the reversal of a previously reported trend in solution‐phase assembly strength when comparing[2.2]pCpTAand[3.3]pCpTAmonomers. The origins of the assembly differences are geometric changes in the association between[n.n]pCpNTAmonomers—revealed by computations and X‐ray crystallography—resulting in a more favorable slipped stacking of the intermolecular π‐surfaces ([n.n]pCpNTAvs.[n.n]pCpTA), and a more complementary H‐bonding geometry ([3.3]pCpNTAvs.[2.2]pCpNTA).
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- PAR ID:
- 10237018
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Chemistry – A European Journal
- Volume:
- 26
- Issue:
- 72
- ISSN:
- 0947-6539
- Format(s):
- Medium: X Size: p. 17588-17597
- Size(s):
- p. 17588-17597
- Sponsoring Org:
- National Science Foundation
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