| title: | Quantitative Self-Consistent Acidity and Basicity Scales in Medium to Low Polarity Solvents and Gas Phase |
|---|---|
| reg no: | ETF5800 |
| project type: | Estonian Science Foundation research grant |
| subject: |
1.6. Physical, Analytical and Inorganic Chemistry |
| status: | accepted |
| institution: | TU Faculty of Physics and Chemistry |
| head of project: | Ivo Leito |
| duration: | 01.01.2004 - 31.12.2007 |
| description: | In water the quantitative data on acid-base properties (pKa values) of compounds is rather abundant and can generally be regarded as reliable. There are, however, a host of unsolved problems and challenges in less polar media and gas phase. In many solvents pKa values are available only for very limited number of compounds, in many cases only relative pKa values are available. Quantitative data for acids and bases with extreme strength (which are the most important and interesting in practice) are often unavailable or are very unreliable. The main goal of the project is situation where reliable quantitative self-consistent acidity and basicity scales having wide pKa range (ca 15-30 orders of magnitude, depending on solvent) exist in a reasonably wide selection of media with polarities ranging from water to the gas phase. Solvents from classes alkanes, halogenated hydrocarbons, ethers, esters, acetonitrile, liquid salts will be used. In some cases (liquid salts, halogenated hydrocarbons) the scale has to be created almost from zero. The problems of the actual state of the ionic species in the solutions and their interactions is an important issue in nonpolar media, having direct relevance to the reliability of the obtained pKa (or pKip) values. Extreme acidities and basicities invoke various side processes that have been studied clearly insufficiently. All these issues will also be tackled. A combination of methods and experimental techniques will be used: the previously developed by us spectrophotometric method of pKa determination, FT ICR for gas-phase measurements. These methods will be helped by conductometry, potentiometry, FT IR spectroscopy, GC-MS and LC-MS. The resulting collection of acidity and basicity scales will be a very useful tool in predicting properties, reactivity, solvation effects and applicability of various compounds in a great variety of different applications (organic synthesis, chemical technology, electrochemical power sources, etc) and form solid basis for further acid-base equilibria measurements in the respective solvents. |
| project group | ||||
|---|---|---|---|---|
| no | name | institution | position | |
| 1. | Lauri Jalukse | TÜ KFI | doktorant | |
| 2. | Ivari Kaljurand | TÜ KFI | teadur | |
| 3. | Eve Koort | TÜ KFI | doktorant | |
| 4. | Ivo Leito | TU Faculty of Physics and Chemistry | associate professor | |
| 5. | Viljar Pihl | TÜ KFI | keemik | |
| 6. | Urmas Pille | TÜ KFI | doktorant | |
| 7. | Lilli Sooväli | TÜ KFI | doktorant | |