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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.
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This content will become publicly available on January 29, 2026
Exploring the Synthesis and Properties of Fluorinated Cationic Triangulenes and Their Precursors
Abstract Fluorination of tris(2,6‐dimethoxyphenyl)‐methylium ((DMP)3C+) was achieved through the partial defluorination of the methyl 2,3,5,6‐tetrafluorobenzoate via nucleophilic aromatic substitution. Using the fluorinated2F((DMP)3C+) as a precursor, fluorinated tetramethoxy‐ and dimethoxyquin‐ acridinium salts (2F4and2F5respectively) and trioxo‐, azadioxo‐, and diazaoxo‐ triangulenium salts (2F6,2F7and2F8respectively) were synthesized successfully in good to moderate yields. Fluorination induced significant red shifts in absorption (16 to 29 nm) and emission (13 to 41 nm) maxima, and increased electrophilicity as evidenced by lower reduction potentials. X‐ray structural analysis showed distinct packing patterns compared to the non‐fluorinated analogues, indicating the presence of molecular dipoles.
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- Award ID(s):
- 2102034
- PAR ID:
- 10571665
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Chemistry – A European Journal
- Volume:
- 31
- Issue:
- 13
- ISSN:
- 0947-6539
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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