Syntheses and Molecular Structures of Titanium Derivatives with Polymerizable Ligands. Toward Extended Arrays

Abstract

The reactions between Ti(OR)4 and allylacetatoacetate (HAAA) in 1:1 or 1:2 stoichiometry at rt gave Ti2(OR)6(AAA)2 R = Et (1), iPr (2) and Ti(OR)2(AAA)2 R = Et (3), iPr (4) species. A monosubstituted derivative Ti2(OiPr)6(AMP)2 (5) was isolated with allylmethylphenol (AMPH). 1 and 5 were characterized by single crystal X‐ray diffraction. Their molecular structures consist of dimers with the polymerizable ligands in terminal positions andbridging alkoxide ligands assembling five and six‐coordinated metal atoms, respectively. The Ti‐O bond lengths of 1 are in the range 1.76(1) to 2.11(1) Å with the variation Ti‐OEt < Ti‐μ‐OEt < Ti‐η2‐O (allylacetatoacetate). All compounds were characterized by FT‐IR and 1H NMR. The possibility to accede to more extended arrays either by hydrolysis or by radical initiated homo‐ or co‐polymerization reactions was investigated for the allylacetato derivatives as well as for Ti(OiPr)2(AAEMA)2 AAEMA = [2‐(methacryloyloxy)ethylacetoacetato] for the latter reactions.

Solvent effects in the formation of hybrid materials based on titanium alkoxide-polysiloxane precursors

“…NMR shifts for the carbonyl atoms from the uncoordinated ligand (around 201 ppm/165.6 ppm) to the one of the chelating ligand (184 ppm/173.4 ppm) confirmed the 1 H NMR results. 33 Furthermore, no decomposition products which are possible side products formed by titanium alkoxide catalyzed transesterification reactions 34 were detected by the spectroscopic methods. In the solid state the formed compound is a binuclear centrosymmetric dimer consisting of two Ti atoms each coordinated by one chelating AAA and two terminal alkoxide ligands.…”

Hybrid Titanium Oxide/Polymer Amphiphilic Nanomaterials with Controlled Size for Drug Encapsulation and Delivery

“…The characterization of the complex is complemented by ATR–FTIR analysis. Spectra show the characteristic bands of Ti(IV) oxo‐alkoxides at 2975 cm −1 (O–H stretching), 1357 cm −1 (CH 3 angular deformation), 1219 cm −1 (CH 2 bending), 1126 cm −1 (Ti(IV)–O–C stretching), 1003 cm −1 (C–O stretching), 849 cm −1 (Ti(IV)–O vibration) and 623 and 528 cm −1 (Ti(IV)–O–Ti(IV) stretching) (Figure S2H, Supporting Information) . The stretching band of ketone carbonyl at 1711 cm −1 confirms the presence of acetone in the medium, though as shown by 1 H‐NMR, mainly in enol form.…”

Hybrid Nanocomposites Based on Metal Oxides and Polysiloxanes with Controlled Morphology

“…Ti(O i Pr) 6 AAA 2 (1) and Zr(O i Pr) 6 AAA 2 (2). The synthesis was based upon a literature known procedure [12]. AAA was added to a solution of Ti(O i Pr) 4 or Zr(O i Pr) 4 in 1:1 ratio in hexane.…”