Sensor Compositions and Methods

Sessler etaU US Patent 6,482,949 (November 19, 2002) Assignee Board of Regents, University of Texas System Utility Analytic Reagents for Detection of Fluoride, Chloride, and 

Oxalyl chloride (0.05 mol) and 25 ml CH2CI2 were cool to —78°C and pyridine (0.12 mol) added causing the formation of a yellow precipitate. To this suspension was added pyrrole (0.1 mol) dissolved in 25 ml CH2CI2, the mixture stirred for 15 minutes at —60°C, and was then quenched with 100 ml 5M HCl. The phases were separated, the aqueous portion extracted with 3 times with 30 ml CH2CI2, combined, washed with 100 ml water, filtered and concentrated. The material was purified by chromatography on silica gel using acetone/hexanes, 80 20, and the product isolated in 38% yield. H- and C-NMR data supplied. 

The product from Step 1 (3.03 mmol) was dissolved in 70 ml HO Ac, 1,2-phenylenediamine (6.62 mmol) dissolved in 30 ml HO Ac added, and the mixture refluxed 90 minutes. The mixture was concentrated, dissolved in 30 ml apiece CH2CI2 and water, the phases separated, and the aqueous phase further extracted with CH2CI2. The organic phases were combined, washed with 50 ml apiece NaHC03, water and brine, dried, and concentrated. The material was purified by chromatography on silica gel using CH2CI2 and the product isolated in 94% as a yellow powder. H- and C-NMR, MS, and elemental analysis data supplied. 

Calixpyrroles, calixpyridinopyrroles, and calixpyridines have been used as analytical tools for the detection of fluoride and phosphate anions (1). Other supramolecular agents used for recognizing, sensing, and transporting anions are discussed (2). 

3-Di-pyridin-2-yl-dibenzoquinoxaline, (I), (3) has been prepared and has photosensitive detection properties for fluoride and phosphate anions (1). 

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