skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

Explore Research Products in the PAR
It may take a few hours for recently added research products to appear in PAR search results.


  • NSF Public Access
  • Search Results
  • Crystal engineering of a 1:1 5-fluorocytosine–4-hydroxybenzaldehyde cocrystal: insights from X-ray crystallography and Hirshfeld analysis

This content will become publicly available on June 1, 2026

Title: Crystal engineering of a 1:1 5-fluorocytosine–4-hydroxybenzaldehyde cocrystal: insights from X-ray crystallography and Hirshfeld analysis
The 1:1 cocrystal of 5-fluorocytosine (5FC) and 4-hydroxybenzaldehyde (4HB), C4H4FN3O·C7H6O2has been synthesized and its structure characterized by single-crystal X-ray diffraction and Hirshfeld surface analysis. The compound crystallizes in the monoclinicP21/cspace group. A robust supramolecular architecture is stabilized by N—H...O, N—H...N, C—H...O and C—H...F hydrogen bonds, formingR22(8),R44(22),R66(32), andR88(34) ring motifs. The N—H...O and N—H...N hydrogen bonds form strong directional interactions, contributing to theR22(8) andR88(34) motifs through dimeric and extended ring structures. O—H...O interactions link 5FC and 4HB molecules, generating anR66(32) ring that enhances the packing. Weaker C—H...F bonds help form theR44(22) tetrameric motif, supporting the overall three-dimensional supramolecular framework. Additionally, C—F...π interactions between the fluorine atom and the aromatic ring add further to the crystal cohesion. Hirshfeld surface analysis and two-dimensional fingerprint plots confirm that O...H/H...O contacts are the most significant, highlighting the central role of hydrogen bonding in the stability and organization of the crystal structure.  more » « less
Award ID(s):
2117502
PAR ID:
10656167
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
International Union of Crystallography
Date Published:
Journal Name:
Acta Crystallographica Section E Crystallographic Communications
Volume:
81
Issue:
6
ISSN:
2056-9890
Page Range / eLocation ID:
549 to 553
Subject(s) / Keyword(s):
cocrystal supra­molecular network dimeric motif tetra­meric motif Hirshfeld surface analysis, fingerprint plots.
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. ; ; ; (, Acta Crystallographica Section C Structural Chemistry)
    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. 
    more » « less
  2. ; (, IUCrData)
    The asymmetric unit in the title salt, (C8H20N)2[SnCl4(C7H4Cl2F3)2], features a di-isobutylammonium cation in a general position and a diorganotin tetrachloride dianion,i.e. tetrachloridobis(3-trifuoromethylphenyl)stannate(IV), located on a centre of inversion; the SnIVatom is octahedrally coordinated. In the crystal, charge-assisted N+—H...Cl hydrogen bonds along with C—H...F contacts occur within supramolecular layers that interdigitate along thea-axis direction. 
    more » « less
  3. ; ; (, Acta Crystallographica Section C Structural Chemistry)
    null (Ed.)
    We report the design, synthesis, and crystal structure of a conjugated aryleneethynyl molecule, 2-(2-{4,5-dimethoxy-2-[2-(2,3,4-trifluorophenyl)ethynyl]phenyl}ethynyl)-6-[2-(pyridin-2-yl)ethynyl]pyridine, C 30 H 17 F 3 N 2 O 2 , that adopts a planar rhombus conformation in the solid state. The molecule crystallizes in the space group P -1, with Z = 2, and features two intramolecular sp 2 -C—H...N hydrogen bonds that co-operatively hold the arylethynyl molecule in a rhombus conformation. The H atoms are activated towards hydrogen bonding since they are situated on a trifluorophenyl ring and the H...N distances are 2.470 (16) and 2.646 (16) Å, with C—H...N angles of 161.7 (2) and 164.7 (2)°, respectively. Molecular electrostatic potential calculations support the formation of C—H...N hydrogen bonds to the trifluorophenyl moiety. Hirshfeld surface analysis identifies a self-complementary C—H...O dimeric interaction between adjacent 1,2-dimethoxybenzene segments that is shown to be common in structures containing that moiety. 
    more » « less
  4. ; ; ; ; (, Acta Crystallographica Section E Crystallographic Communications)
    A CuIIcoordination polymer,catena-poly[[[aquacopper(II)]-bis(μ-4-aminobenzoato)-κ2N:O;κ2O:N] monohydrate], {[Cu(pABA)2(H2O)]·H2O}n(pABA =p-aminobenzoate, C7H4NO2−), was synthesized and characterized. It exhibits a one-dimensional chain structure extended into a three-dimensional supramolecular assembly through hydrogen bonds and π–π interactions. While the twinned crystal shows a metrically orthorhombic lattice and an apparent space groupPbcm, the true symmetry is monoclinic (space groupP2/c), with disordered Cu atoms and mixed roles of water molecules (aqua ligand/crystallization water). The luminescence spectrum of the complex shows an emission at 345 nm,cf.349 nm forpABAH. 
    more » « less
  5. ; ; ; ; ; ; ; (, Acta Crystallographica Section E Crystallographic Communications)
    The reactions of triphenylsulfonium chloride ([TPS][Cl]) with various acids in methanol yield the corresponding salts triphenylsulfonium triiodide, C18H15S+·I3−or [TPS][I3] (I), triphenylsulfonium perchlorate, C18H15S+·ClO4−or [TPS][ClO4] (II), and triphenylsulfonium hexafluorophosphate, C18H15S+·PF6−or [TPS][PF6] (III), as crystalline products. These crystals were structurally characterized by single-crystal X-ray diffraction. In all three compounds, the sulfur atom in the triphenylsulfonium cation adopts a distorted trigonal–pyramidal geometry. [TPS][I3] (I) and [TPS][PF6](III) both crystallize in the space groupP21/n, while [TPS][ClO4] (II) crystallizes inP21. The S—C bond lengths are comparable across the three salts, and the S—C—S bond angles are consistently between 102 and 106°. Hirshfeld surface analyses reveal that each structure is dominated by hydrogen-based intermolecular contacts, supplemented by anion-specific interactions such as I...H in (I), O...H in (II), and F...H in (III). These contacts organize the ions into mono-periodic ribbon- or chain-like arrangements. No significant π–π stacking is observed. 
    more » « less
  • Citation Formats
  • MLA
  • APA
  • Chicago
  • BibTeX
  • Save / Share this Record
  • Send to Email