Synthesis, Characterization, and Surface Tethering of Sulfide-Functionalized Ti₁₆-oxo-alkoxy Cages

Eslava, Salvador; Papageorgiou, Anthoula C.; Beaumont, Simon K.; Kyriakou, Georgios; Wright, Dominic S.; Lambert, Richard M.

Abstract

The parent cage [Ti16O16(OEt)32] readily undergoes ligand exchange with a range of primary alcohols to yield species of the type [Ti16O16(OEt)32−x(OR′)x], with R′ = Me, n-Pr, and n-Bu with x of up to 8. Attempted ligand exchange using the thiol [HO(CH2)4SH] in an attempt to produce functionalized cages suitable for tethering to Au surfaces failed, resulting only in the polymerization of the Ti oxo-cores. However, the use of the thioether [HO(CH2)4SCH3] resulted in successful thio-functionalization and preservation of the Ti16 cage core, likely due to methyl protection on the sulfide which precludes further intermolecular reaction with other cage molecules. ESI-MS and NMR showed that the resulting substituted cage [Ti16O16(OEt)24{O(CH2)4SCH3}8] contained eight methylthio-n-butoxy ligands in two groups of four pseudoequivalent positions. High resolution XPS and STM demonstrated that this sulfide-functionalized cage underwent covalent tethering to Au surfaces involving five sulfur linkages per cage, forming a monolayer of adsorbed species in which the molecular integrity had been preserved. In contrast, the parent oxo-alkoxy cage underwent extensive decomposition, rendering it useless as a building block for specific surface architectures.

Citation

Eslava, S., Papageorgiou, A. C., Beaumont, S. K., Kyriakou, G., Wright, D. S., & Lambert, R. M. (2010). Synthesis, Characterization, and Surface Tethering of Sulfide-Functionalized Ti₁₆-oxo-alkoxy Cages. Chemistry of Materials, 22(18), 5174-5178. https://doi.org/10.1021/cm101039k

• Journal Article Type: Article
• Online Publication Date: Aug 17, 2010
• Publication Date: Sep 28, 2010
• Deposit Date: Mar 8, 2014
• Journal: Chemistry of Materials
• Print ISSN: 0897-4756
• Electronic ISSN: 1520-5002
• Publisher: American Chemical Society
• Peer Reviewed: Peer Reviewed
• Volume: 22
• Issue: 18
• Pages: 5174-5178
• DOI: https://doi.org/10.1021/cm101039k
• Public URL: https://durham-repository.worktribe.com/output/1468147