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Updated: Mar 22, 2026
Synthesis of Information-bearing Peptoids and their Sequence-directed Dynamic Covalent Self-assembly
Published on: February 6, 2020
Control over the Self-Assembly Modes of Pt(II) Complexes by Alkyl Chain Variation: From Slipped to Parallel π-Stacks
Naveen Kumar Allampally1, María José Mayoral1,2, Sarayute Chansai3
1Institut für Organische Chemie and Center for Nanosystems Chemistry, Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.
Abstract:
We report the self-assembly of a new family of hydrophobic, bis(pyridyl) Pt(II) complexes featuring an extended oligophenyleneethynylene-derived π-surface appended with six long (dodecyloxy (2)) or short (methoxy (3)) side groups. Complex 2, containing dodecyloxy chains, forms fibrous assemblies with a slipped arrangement of the monomer units (dPt⋅⋅⋅Pt ≈14 Å) in both nonpolar solvents and the solid state. Dispersion-corrected PM6 calculations suggest that this organization is driven by cooperative π-π, C-H⋅⋅⋅Cl and π-Pt interactions, which is supported by EXAFS and 2D NMR spectroscopic analysis. In contrast, nearly parallel π-stacks (dPt⋅⋅⋅Pt ≈4.4 Å) stabilized by multiple π-π and C-H⋅⋅⋅Cl contacts are obtained in the crystalline state for 3 lacking long side chains, as shown by X-ray analysis and PM6 calculations. Our results reveal not only the key role of alkyl chain length in controlling self-assembly modes but also show the relevance of Pt-bound chlorine ligands as new supramolecular synthons.
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