Mixed‐Ligand Titanium “Oxo Clusters”: Structural Insights into the Formation and Binding of Organic Molecules and Transformation into Oxide Nanostructures on Hydrolysis and Thermolysis

Abstract

We present the structure of a new tetranuclear titanium oxo complex containing the antibacterial agent triclosan. This provides a good model for the interaction between triclosan and titania, which may be used for drug‐delivery applications. The antibacterial activity of the hydrolyzed complex against Staphylococcus aureus is investigated. Thereafter, we use the obtained titanium oxo complex to demonstrate its susceptibility towards hydrolysis, contrary to the widespread belief that titanium oxo complexes are water‐stable, and demonstrate that it transforms into titania (anatase) on contact with water. Both hydrolysis and thermolysis of the complex yield titania particles, of very uniform size and shape, that connect into 3D nanostructures; this is of interest for practical applications.

Hybrid Drug Delivery Patches Based on Spherical Cellulose Nanocrystals and Colloid Titania—Synthesis and Antibacterial Properties

“…The aromatic rings not containing the phenol group are turned towards each other because of π–π stacking interactions. Preliminary structural characterization of the compound 1 was reported earlier in [ 48 ]. Compound 2 is a triclinic pentanuclear (Ti 5 O 2 ) titanium oxo-complex ( Figure 4 b), also belonging to the space group P-1.…”

Titanium phosphonate oxo-alkoxide “clusters”: solution stability and facile hydrolytic transformation into nano titania

“…In our previous work with phenoxide and carboxylate containing titanium alkoxides we have demonstrated their facile hydrolysis in contact with water. 5,43 We wanted to continue our investigation on phosphonate-containing titanium alkoxide complexes, which have recently been reported as hydrolytically stable and tested in aquatic media for UV-driven water-splitting. 29,30,32 Titanium alkoxides are oen modied to contain chelating (and bridging) ligands to stabilize the colloid oxide phase.…”

“…[1][2][3] Monodisperse crystalline titania (anatase) nanoparticles can be obtained from titanium coordination compounds by shi in solution equilibrium 4 or upon hydrolysis and thermolysis. 5 Titanium coordination complexes also nd use as catalysts, particularly for olen polymerization. 6,7 The discovery of photocatalytic activity of titania by Honda and Fujishima 8 in the 1970's has resulted in a number of applications, such as selfcleaning glasses, wastewater remediation and hydrogen gas production.…”

“…While chelates of phosphonate to titanium center are also known, 27 they do not appear to be common, probably because of straining bond angles. Because of the high reactivity of modi-ed titanium alkoxo-complexes, 28 these compounds readily hydrolyze into titania 5,28 in the presence of moisture or even traces of water in solvents. The photocatalytic activity of titanium (oxo-) complexes and titanium phosphonate complexes has been reported in several recent papers, [29][30][31][32] in which liquid aqueous medium was applied.…”

In Situ Self‐Assembled Polyoxotitanate Cages on Flexible Cellulosic Substrates: Multifunctional Coating for Hydrophobic, Antibacterial, and UV‐Blocking Applications

“…The documented applications of POT cages include gas adsorption, photocatalytic water splitting, pollutant degradation, electrochemical water oxidation, dye‐sensitized solar cells, fluorescent labeling, and TiO 2 nanoparticle and thin film production . Despite these diverse applications, the potential of POT cages in the area of flexible materials has not so far been explored.…”