Crown-ether-like structures derived from a Ti(8)O(8) (carboxylate)(16) metallacycle
Christine Artner1, Matthias Czakler, Ulrich Schubert
1Institute of Materials Chemistry, Vienna University of Technology, 1060 Wien (Austria).
Chemistry (Weinheim an Der Bergstrasse, Germany)
|December 31, 2013
Summary
New mixed-metal clusters featuring titanium, strontium, and lead were synthesized. These novel titanium-based clusters encapsulate strontium or lead atoms within a unique Ti8 O8 metallacycle structure.
Area of Science:
- Inorganic Chemistry
- Materials Science
- Coordination Chemistry
Background:
- Mixed-metal clusters offer unique structural and electronic properties.
- Titanium alkoxides are versatile precursors in inorganic synthesis.
- Strontium and lead acetates are common sources for these metals.
Purpose of the Study:
- To synthesize novel mixed-metal clusters incorporating titanium, strontium, and lead.
- To elucidate the structural characteristics of these newly formed clusters.
- To investigate the coordination environment of strontium and lead atoms within the titanium framework.
Main Methods:
- Reaction of titanium alkoxides with strontium or lead acetate in the presence of methacrylic acid.
- Structural characterization of the resulting mixed-metal clusters.
- Analysis of coordination modes and bonding within the cluster structures.
Main Results:
- Successful synthesis of mixed-metal clusters derived from a Ti8 O8 (methacrylate)16 metallacycle.
- Strontium and lead atoms were found to occupy the central cavity of the Ti8 O8 ring.
- Coordination of Sr/Pb atoms involves both crown-ether-like interactions with ring oxygen atoms and bridging carboxylate ligands.
- A distinct cluster structure, Pb2 Ti6 O5 (OiPr)3 X(methacrylate)14, showed lead atoms coordinated by a fragment of the Ti8 O8 (methacrylate)16 metallacycle.
Conclusions:
- Novel mixed-metal clusters containing titanium, strontium, and lead have been synthesized.
- The structures reveal the encapsulation of Sr/Pb atoms within a Ti8 O8 metallacycle framework.
- Bridging carboxylate ligands play a crucial role in stabilizing the metal coordination.
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