|M.Sc Student||Olga Tobias|
|Subject||Preparetion and Caracterization of a New Receptor for|
Anions and Organophosphonates
|Department||Department of Chemistry||Supervisors||Professor Eichen Yoav|
|Dr. Denekamp Chagit|
|Full Thesis text - in Hebrew|
Anions play a major role in many biological processes and in a variety of industries, such as agricultural fertilizers, food additives, etc. Organophosphorus compounds can be found both in different fertilizers and nerve agents. Of all phosphonic compounds, phosphonic acids, which are the hydrolysis products of a variety of nerve agents and fertilizers, are the most stable compounds. These compounds form single-charged anions in both liquid and gaseous phases, and can be readily used for designing organophosphonic sensors.
The main aim for this research was to design, prepare, and characterize new receptors for organophosphorus anions.
A stable Triethylpyrrolemethane (TEPM) molecule was synthesized, using the synthesis of tripyrrolemethane (TPM) receptor, which exhibited a high binding affinity towards fluoride and phosphate anions, as was reported by our group a few years ago. The examination of the new receptor’s anion binding properties in solution and in gaseous phases was performed using 1H-NMR spectroscopy titrations.
The results of titrations with halides and heteroatomic anions, such as azide and phosphate, show good binding properties with many of the introduced anions, however the selectivity of the host towards one anion is very low. A qualitative analysis in the gaseous phase using ESI-MS technique supports the results obtained from solution. In the gaseous phase especially 1:1 [Host]:[Guest] complexes were seen, in a high abundance.
The titrations with organophosphorous anions demonstrated complexes with different binding constants in all three solvents, in solution and in the gaseous phase. Unfortunately, the TEPM receptor selectivity towards organophosphorous anions was very poor.