Hexafluorophosphate, PFj

There are some indications that at 70—80° C there may be some termination occurring even with the PFg gegenion. In polymers produced at 70° C. Sims (26) was able to detect some fluorine which he suggests may have formed from a reaction of the type given below  

Another possibility would be the reaction analogous to equation (22)  

As we have stated before (Section IIIB4) it is probable that Ph3C+ PFq and 4-ClPhNJPFg initiate polymerization by the same mechanism and lead to the same propagation reaction. These suggestions are reinforced by the data (20, 52) shown in Table 3. For similar catalyst concentrations, polymers of similar intrinsic viscosity are obtained. 

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Table 5-1. Enantioselectivities determined for several drugs. All experiments were performed at room temperature, except those marked with, which were performed at 4 °C. In some cases a lipophilic anion was used to facilitate the solubilization of the drug in the organic phases (PFj = hexafluorophosphate BPh = tetraphenyl borate). DHT = dihexyl tartrate DBT = dibenzoyl tartrate PLA = poly (lactic acid). ...

Bhargava, B.L., and Balasubramanian, S., Insights into the structure and dynamics of a room-temperature ionic liquid Ab initio molecular dynamics simulation studies of l-n-butyl-3-methylimidazolium hexafluorophosphate ([bmim][PFj]) and the [bmim][PFj]-C02 mixture, /. Phys. Chem. B, 111, 4477-4487, 2007. 

Triolo, A., Mandanici, A., Russina, O., Rodriguez-Mora, V., Cutroni, M., Hardacre, C., Nieuwenhuyzen, M., Bleif, H.-J., Keller, L., and Ramos, M. A., Thermodynamics, structure, and dynamics in room temperature ionic liquids The case of l-butyl-3-methyl Imidazolium hexafluorophosphate ([bmim][PFJ),7. Phys. Chem. B, 110,21357-21364, 2006. 

Of metallic salts M(PX6) only hexafluorophosphates appear to be known, and of these the salts with large cations such as NH4, K , Cs", Ba ", and Co(NH3)6 , are the most stable in the solid state. The first three have been shown to crystallize with a NaCl-like packing of M and octahedral PF ions. The crystal structure of HPFg. 6 HjO is described on p. 544. In the PFj ion in this crystal P-F was found to be 1 73 A, but in NaPFg the length of this bond is apparently only T58 A. Moreover, in NaPFg. the ion was found to be distorted, with four... 

Tris(acetonitrile)dicarbonyl(i -l,2,3-triphenylcyclopropenyl)molybdenum(I) Hexafluorophosphate (15, X = PFj) Typical Procedure ... 

Direct-current (d.c.) polarography is approximately a constant-potential experiment in which the current passed during the lifetime of a single Hg drop (ca. 1-7 s) is measured at a succession of potentials. The potential applied to the dme is scanned slowly (1-5 mV s ), and the resulting current-potential profile is recorded. Figure 1 shows two polarographic scans, one on the residual electrolyte (0.1 M [n-Bu N][PFj] in dimethoxyethane) and one to which cobaltocinium hexafluorophosphate (5 X 10 M) is added. The half-wave potential, E, and the limiting current, i, are derived from this S-shaped curve. 

The hexafluorophosphate analog can be prepared from [Rh(nbd)(PPh3)2][PFj] (equation 325). Bis-1,2- diphenylphosphino)ethane displaces all ligands from the cation, but the reaction is obviously more complex since NjO and OPPhj are also produced (equation 326). ... 

Mtrotifum hexafluorophosphate (NOj PFJ) in contrast to NO2 BF was found to be much more soluble in many solvents. Its solubility in niuo. methane for example is >30%. Consequently is a very convenient nitrating agent for aromatics (as well as aliphatics). It can be prepared similatlj to tetrafiuoroborate by using HF and PF5. Lack of ready availability of PFj may be, however, a limitation. 

Lithium hexafluorophosphate is thermally unstable in the solid state [52], where it decomposes at about 30 °C [53]. In solvents and solvates it is more stable. Decomposition begins in the range from 80 °C [53] to about 130 °C [13], yielding scarcely soluble LiF and the Lewis acid PFj which in turn initiates polymerization of cyclic... 

T. Endo, H. Murata, M. Imanari, N. Mizushima, H. Seki, S. Sen, K. Nishikawa, A comparative study of the rotational dynamics of PFJ anions in the crystals and hquid states of l-butyl-3-methylimidazolium hexafluorophosphate results from P NMR spectroscopy, . Phys. Chem. B 117 (1) (2013) 326—332. 

Han and coworkers [13] further studied the phase behavior of toluene/TX-100/1-butyl-3-methylimidazolium hexafluorophosphate ([bmim][PF ]) system. As shown in Figure 16.2, the single-phase microemulsion area covers about 75% of the phase diagram at 25 °C. A transition from IL-in-oil microemulsion (marked as A) via a bicontinuous region (marked as B) to an oil-in-IL microemulsion (marked as C) occurs with the increase of weight fraction of TX-lOO and [bmim][PFJ. 

Subsequently, Han et al. [34] reported IL-in-IL nanoemulsions for the first time. Assisted with a certain amount of surfactant AOT, the hydrophilic IL PAF and the hydrophobic IL 3-methyl-l-octylimidazolium hexafluorophosphate ([omimjPF ) formed [omimjPF -in-PAF microemulsions when the volume ratio of [omimjPF was relatively low. With the increase in volume ratio of [omimjPF, unstable [omim] PFj-in-PAF nanoemulsions were formed, which were transparent before phase separation. The conductivity of [omimjPF -in-PAF nanoemulsions was much lower than that of [omim]PFj-in-PAF microemulsions. Small-angle X-ray scattering (SAXS) experiment demonstrated that the microdroplets of the nanoemulsion were spherical and the gyration radii of the microdroplets decreased from 19.3 to 15.7 nm when the volume ratio of [omimjPF was reduced from 0.35 to 0.25. Utilizing this IL-in-IL nanoemulsion as the reaction medium, stable and crystallined metal-organic framework (MOF) nanorods were successfully synthesized, indicating potential applications of IL-in-IL nanoemulsions as well as microemulsions in other fields. 

Chakrabarty, D., Chakraborty, A., Seth, D., Hazra, R, and Sarkar, N. 2004. Dynamics of solvation and rotational relaxation of Coumarin 153 in 1-butyl-3-methylimida-zolium hexafluorophosphate [bmim][PFJ-water mixtures. Chem. Phys. Lett. 397, 469-474. 

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