Sodium hexafluorophosphate

In 2002 Mehnert and co-workers were the first to apply SILP-catalysis to Rh-catalysed hydroformylation [74], They described in detail the preparation of a surface modified silica gel with a covalently anchored ionic liquid fragment (Scheme 7.7). The complex N-3-(3-triethoxysilylpropyl)-4,5-dihydroimidazole was reacted with 1-chlorobutane to give the complex l-butyl-3-(3-triethoxysilylpropyl)- 4,5-dihydroimidazolium chloride. The latter was further treated with either sodium tetrafluoroborate or sodium hexafluorophosphate in acetonitrile to introduce the desired anion. In the immobilisation step, pre-treated silica gel was refluxed with a chloroform solution of the functionalised ionic liquid to undergo a condensation reaction giving the modified support material. Treatment of the obtained monolayer of ionic liquid with additional ionic liquid resulted in a multiple layer of free ionic liquid on the support. 

Cohydrolysis of MnLCls (L= 1,4,7-triazacyclononane) and RuL Cl3 H20 (L = 1,4,7-trimethyl-1,4,7-triazacyclononane) in equimolar amounts in methanol containing an excess of sodium acetate gives rise to the asymmetric heterodinuclear species [L Ru(/i-0)(/u-CH3C00)2MnL]PFg on addition of sodium hexafluorophosphate. A model to interpret the strong spin-exchange coupling in this complex was presented." ... 

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

The reaction of l- -butyl-3-methylimidazolium chloride (BMIC) with sodium tet-rafluoroborate or sodium hexafluorophosphate produced the room temperature-, air-and water-stable molten salts (BMr)(BF4 ) and (BMTXPFg ), respectively in almost quantitative yield. The rhodium complexes RhCKPPhjls and (Rh(cod)2)(BF4 ) are completely soluble in these ionic liquids and they are able to catalyze the hydrogenation of cyclohexene at 10 atm and 25°C in a typical two-phase catalysis with turnovers up to 6000 (see fig. 6.10). 

Sodium hexafluorophosphate [21324-39-0] M 167.9. Recrystd from acetonitrile and vacuum dried for 2 days at room temperature. It is an irritant and is hygroscopic. [Delville et al. JACS 109 7293 1987]. 

Potassium, sodium and lithium tetrafluoroborate as well as sodium hexafluorophosphate and hexafluoroantimonate can be used to fluorinate organosilicon chlorides.64 65 An overview is reported in Table 10.65... 

Sodium diimidotrimetaphosphate, Na3P308(NH)2, formation and basic hydrolysis of, in preparation of pentasodium diimido-triphosphate, 6 105ra., 106 Sodium diimidotriphosphate, Na5P308(NH)2-6H20, 6 104 Sodium diphosphates, 3 98, 99, 100 Sodium dithionate, 2 170 Sodium (ethylenediaminetetra-acetato)cobaltate(III), 5 186 Sodium hexafluorophosphate, 3 111, 115... 

The addition is mildly exothermic. Sodium hexafluorophosphate is commercially available although significantly more expensive. The sodium salt may be used in place of the hexafluorophosphoric acid by omitting the initial sodium hydroxide charge. 

The addition of sodium hexafluorophosphate to the aqueous solution of [Ni(Me,[14]-1.3.8.10-tetraeneN,)] (NOj), in the above procedure leads to the isolation of the hexa-fluorophosphate salt of the complex. 

Polymerization was performed in a 1 L autoclave at 50 °C for 2 h at 6 bar ethene pressure. The N,N-PdMeCl complexes were activated through reaction with one equivalent of sodium hexafluorophosphate. Polymerization results are summarized in Tab. 3.5. It was found that the activity of the bromo derivative indeed is higher, but only by a factor of two. In addition, the molecular weight of the products is lower and the number of branches are higher. 

Sodium hexafluorophosphate mono hydrate NaPF3 H3O 20644-16-9 186.969 col orth cry 2.369 103" s FtOH, MeOH, ace... 

A microwave-assisted preparation of a series of l-alkyl-3-methylimidazolium halide ILs has been described [17]. The reaction is run in solvent-free conditions with a near-stoichiometric amount of reactants, and the imidazolium halides are obtained in high yield. It is also possible to perform the subsequent metathesis reaction with sodium hexafluorophosphate by means of microwave radiation and then to form the final product in a one-pot reaction [18]. Due to the fact that ILs absorb microwave energy in a very efficient way, they are believed to be well suited for large-scale microwave-assisted synthesis (that is, for reaction mixtures of more than 100 L). 

Other attempts have been made to simplify the synthesis of ILs and to increase the overall yield. For example, the synthesis of [BMI][PFg] was described using the desired product as solvent. Then the heating of a mixture of N-methylimidazole, chlorobutane, and sodium hexafluorophosphate for 35 h at 80 °C in [BMI][PFg] led... 

Sodium hexafluorophosphate bound Amberlite resin rt, water and methanol (1 1), good to excellent yield, 5-8 h 85... 

This strategy has been also employed [83-86] to a limited extent (Scheme 2.10) with diamine nucleophile. A hiomimetic approach can be used to synthesize Qxs (entry 1, Table 2.4) using (3-CD as a catalyst. The use of trimethylsilyl chloride (TMSCl) as a catalyst has also been reported however, this method requires longer time and is applicable for only limited substrates (entry 2, Table 2.4). Other methods used the solid-supported catalyst sodium hexafluorophosphate bound Amberlite resin and micellar sodirrm dodecylsulfate (SDS entries 3 and 4, Table 2.4). 

Ghosh P, Mandal A (2012) Synthesis of functionalized benzimidazoles and quinoxalines catalyzed by sodium hexafluorophosphate bound Amberlite resin in aqueous medium. Tetrahedron Lett 53 6483-6488... 

Methanol solutions of COaEtHLl (0.1 M, 1 mL), cadmium acetate (0.1 M, 2 mL), sodium acetate (0.1 M, 1 mL) and sodium hexafluorophosphate (0.1 M, 3 mL) were combined with methanol (2 mL) and the yellow solution was left to evaporate slowly at room temperature. White crystals were obtained after 5 days. After recrystaUization from a minimum of hot methanol the complex was obtained in a 66 % yield (40 mg). 

C02EtHL2 (180 mg, 0.34 mmol) was dissolved in methanol and cadmium(II) acetate dihydrate (183 mg, 0.68 mmol) and sodium acetate (56 mg, 0.68 mmol) added. The yellow solution was subsequently refluxed for 30 min and then allowed to cool to room temperature and sodium hexafluorophosphate (115 mg, 0.68 mmol) added. After filtration the yellow solution was left to evaporate at room temperature to leave a yellow oil. Attempts to crystallize the complex from a range of solvents were unsuccessftil. The complex was, however, readily formed as confirmed by mass spectroscopic measurements. After repeated (5x) evaporation of the methanolic complex solution a white powder was obtained. 

C02EtHL2 (100 mg, 0.19 mmol) was dissolved in methanol (4 mL) and was combined with a solution of cobalt(II) acetate tetrahydrate (95 mg, 0.38 mmol) in methanol (6 mL). Subsequently solid sodium hexafluorophosphate (95 mg, 0.57 mmol) was added. The solution was left in a beaker at room temperature to evaporate. Pink crystals which were suitable for X-ray crystallography were obtained in 70 % yield (120 mg). 

CH3HL2 (125 mg, 0.25 mmol) was dissolved in methanol (2 mL) and a methanol (3 mL) cobalt(II) acetate tetrahydrate (125 mg, 0.5 mmol) solution was added dropwise at room temperature. Subsequently sodium hexafluorophosphate (140 mg, 0.8 mmol) dissolved in methanol (3 mL) was added. The pink crystals which emerged upon standing after a couple of were filtered and dried in air (150 mg, 71 %). Crystals were obtained suitable for X-ray crystallography after 2 days by using only one equivalent Co(II) and adding the hexafluorophosphate as solid. 

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