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2,4,6-Triaminopyrimidine is an interesting and challenging molecule due to the presence of multiple hydrogen-bond donors and acceptors. Its noncovalent interactions with a variety of carboxylic acids provide several supramolecular aggregates with frequently occurring molecular synthons. The present work focuses on the supramolecular interactions of 2,4,6-triaminopyrimidinium 3-(indol-3-yl)propionate–3-(indol-3-yl)propionic acid (1/1), C4H8N5+·C11H10NO2−·C11H11NO2, (I), 2,4,6-triaminopyrimidinium 2-(indol-3-yl)acetate, C4H8N5+·C10H8NO2−, (II), 2,4,6-triaminopyrimidinium 5-bromothiophene-2-carboxylate, C4H8N5+·C5H2BrO2S−, (III), and 2,4,6-triaminopyrimidinium 5-chlorothiophene-2-carboxylate, C4H8N5+·C5H2ClO2S−, (IV). All four salts exhibit robust homomeric and heteromericR22(8) ring motifs. Salts (I) and (II) develop sextuple [in (I)] and quadruple [in (I) and (II)] hydrogen-bonded arrays through fused-ring motifs. Salt (II) exhibits a rosette-like architecture. Salt (IV) is isostructural and isomorphous with salt (III), exhibiting an identical crystal structure with a different composition and an identical supramolecular architecture. In salts (III) and (IV), a linear hetero-tetrameric motif is formed and, in addition, both salts exhibit halogen–π interactions which enhance the crystal stability. All four salts develop a supramolecular hydrogen-bonded pattern facilitated by several N—H...O and N—H...N hydrogen bonds with multiple furcated donors and acceptors.
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Synthesis and crystallographic characterization of 6-hydroxy-1,2-dihydropyridin-2-one
The title compound, C5H5NO2, is a hydroxylated pyridine ring that has been studied for its involvement in microbial degradation of nicotinic acid. Here we describe its synthesis as a formic acid salt, rather than the standard hydrochloride salt that is commercially available, and its spectroscopic and crystallographic characterization.
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- Award ID(s):
- 1817633
- PAR ID:
- 10496168
- Publisher / Repository:
- Acta Crystallogr E Crystallogr Commun
- Date Published:
- Journal Name:
- Acta Crystallographica Section E Crystallographic Communications
- Volume:
- 79
- Issue:
- 12
- ISSN:
- 2056-9890
- Page Range / eLocation ID:
- 1147 to 1150
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1107/S205698902300974X
