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Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
The solution structures and dynamics and the solid-state structures of substituted cyclopentadienyltitanium(IV)
Franc Perdih1, Andrej Pevec, Sasa Petricek
1Faculty of Chemistry and Chemical Technology, University of Ljubljana, Askerceva 5, Ljubljana, Slovenia.
Inorganic Chemistry
|September 12, 2006
Summary
Organotitanium fluorides form crystalline dimers and tetramers. In solution, temperature and dilution favor smaller organotitanium fluoride molecules, shifting equilibria from tetramers to dimers and monomers.
Area of Science:
- Organometallic Chemistry
- Solid-State Chemistry
- Spectroscopy
Background:
- Organotitanium fluorides exhibit complex aggregation behavior in solid and solution states.
- Understanding these equilibria is crucial for controlling reactivity and properties.
Purpose of the Study:
- To investigate the aggregation states and solution equilibria of organotitanium fluorides.
- To determine the thermodynamic and kinetic parameters governing these transformations.
Main Methods:
- Variable-temperature 1H and 19F NMR spectroscopy.
- Vapor pressure osmometry.
- Crystallography (implied by crystalline dimer/tetramer formation).
Main Results:
- Organotitanium fluorides form dimers and tetramers in the solid state and solution.
- In solution, equilibria exist between monomeric, dimeric, trimeric, and tetrameric species.
- Temperature and dilution shift equilibria towards smaller aggregates (monomers, dimers).
- Thermodynamic data for tetramer-to-dimer and dimer-to-monomer dissociation were determined.
Conclusions:
- Organotitanium fluoride aggregation is a dynamic process influenced by temperature and concentration.
- Detailed structural and energetic insights into these equilibria were obtained.
- Proposed dissociation pathways and transition states provide a deeper understanding of organotitanium fluoride chemistry.
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