Potassium hexafluorophosphate

Potassium hexafluorophosphate [ 17084-13-8 j M 184.1, pK 0.5, pK j 5.12 (for fluorophosphoric acid H2PO3F). Crystd from alkaline aqueous solution, using polyethylene vessels, or from 95% EtOH, and dried in a vacuum desiccator over KOH. 

Procedure. To an aliquot containing 36-55 mg of potassium hexafluorophosphate add aqueous ammonia until the solution is basic. A final concentration... 

Fig. 9. Capacitance-potential curves for a number of common electrochemical solvents containing O lM potassium hexafluorophosphate, a relatively non-adsorbing electrolyte. (From Payne 1967, 1970.)...

The solvents themselves are adsorbed on the electrode surface, as is shown by the capacitance-potential graphs illustrated in Fig. 9 (Payne, 1967, 1970) potassium hexafluorophosphate, the electrolyte in each of the solvents, is thought to be adsorbed only very weakly. The solvents show somewhat differing curves and the peaks have been interpreted both in terms of competition between the solvent and anions for sites at the surface and also in terms of solvent reorientation. Ethers are adsorbed from the amide solvents most strongly at the potentials around the peaks and this has been postulated to be due to an increase in freedom for the solvent to rotate at these potentials (Dutkiewicz and Parsons, 1966). 

C. 1- Butyl-3-methylimidazolium hexafluorophosphate. A 1-L, one-necked, round-bottomed flask (Note 13) is charged with 65.6 g (0.37 mol, 1 equiv) of 1- butyl-3-methylimidazolium chloride, and 69.3 g (0.37 mol, 1 equiv) of potassium hexafluorophosphate (Note 19) in 70 ml of distilled water. The reaction mixture is stirred at room temperature for 2 hr affording a two-phase system. The organic phase is washed with 3 X 50 mL of water and dried under reduced pressure (0.1 mbar, 0.001 mm). Then 100 ml of dichloromethane and 35 g of anhydrous magnesium sulfate are added. After 1 hr, the suspension is filtered and the volatile material is removed under reduced pressure (0.1 bar, 0. 1 mm) at 30°C for 2 hr to afford 86.4 g (0.29 mol, 81%) of 1- butyl-3-methylimidazolium hexafluorophosphate as alight yellow viscous liquid, mp 10°C (Notes 20 and 21). 

Potassium hexafluorophosphate (Strem Chemicals Inc.) is used as received. Sodium hexafluorophosphate can be also used although it is much more expensive. 

Potassium tetrafluoroborate Borate(l-), tetrafluoro-, potassium (8,9) (14075-53-7) Potassium hexafluorophosphate Phosphate(l-), hexafluoro-, potassium (8,9) (17084-13-8)... 

Silver nitrate was obtained from ACROS and potassium hexafluorophosphate from Aldrich Chemical Company, Inc. 

The biaryl 132 was converted into methyl viologen 8 by treatment with methyl iodide and anion exchange with potassium hexafluorophosphate (Scheme 35) <2005TL7291>. 

Franco et al. [45] described an HPLC method for simultaneous determination of the R-( ) and (S)-(+)-enantiomers of vigabatrin in human serum after precolumn derivatization with 2,4,6-trinitrobenzene sulfonic acid (TNBSA) and detection at 340 nm. Separation was achieved on a reversed phase chiral column (Chiralcel-ODR, 25 cm x 4.6 mm) using 0.05 M potassium hexafluorophosphate (pH4.5) acetonitrile ethanol (50 40 10) as a mobile phase at a flow rate of 0.9 ml/min. The calibration graphs for each enantiomer were linear over the concentration range of 0.5-40 fig/ml with a limit of quantification of 0.5 fig/ml. No interferences were found from commonly coadministered antiepileptic drugs. 

Pour the mixture into a 250 mL separating funnel. Collect the organic layer in a 500 mL round-bottomed flask. Add 100 mL of a saturated potassium hexafluorophosphate solution and stir overnight with a magnetic stirrer. 

Examples of the use of coordination names in the binary system are the solids hexaamminenickel dibromide, [Ni(NH3)6]Br2, and potassium hexafluorophosphate(V), K[PF6],... 

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