The crystal structures of two intermediates, 4-amino-3,5-difluorobenzonitrile, C7H4F2N2(I), and ethyl 4-amino-3,5-difluorobenzoate, C9H9F2NO2(II), along with a visible-light-responsive azobenzene derivative, diethyl 4,4′-(diazene-1,2-diyl)bis(3,5-difluorobenzoate), C18H14F4N2O4(III), obtained by four-step synthetic procedure, were studied using single-crystal X-ray diffraction. The molecules ofIandIIdemonstrate the quinoid character of phenyl rings accompanied by the distortion of bond angles related to the presence of fluorine substituents in the 3 and 5 (ortho) positions. In the crystals ofIandII, the molecules are connected by N—H...N, N—H...F and N—H...O hydrogen bonds, C—H...F short contacts, and π-stacking interactions. In crystal ofIII, only stacking interactions between the molecules are found.
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Crystal structure of a hydrogen-bonded 2:1 co-crystal of 4-nitrophenol and 4,4′-bipyridine
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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- Award ID(s):
- 1847926
- PAR ID:
- 10651412
- Publisher / Repository:
- Acta Cryst E, Crystallographic Communications
- Date Published:
- Journal Name:
- Acta Crystallographica Section E Crystallographic Communications
- Volume:
- 80
- Issue:
- 11
- ISSN:
- 2056-9890
- Page Range / eLocation ID:
- 1135 to 1137
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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