Nitrosonium hexafluorophosphate

Olah, G.A., Salem, G., Staral, J.S., and Ho, T.L. 1978. Preparative carbocation chemistry. 13. Preparation of carbocations from hydrocarbons via hydrogen abstraction with nitrosonium hexafluorophosphate and sodium nitrite trifluoromethanesulfonic acid. 7. Org. Chem. 43 173-175. 

Allyl halides react with acetonitriles after anodic oxidation - under acidic conditions or in the presence of nitrosonium hexafluorophosphate to give the corresponding amides. 

Nitrosonium hexafluorophosphate (Nitrosyl hexafluorophosphate). NO PFe. Mol. wl. 174,99. Supplier Ozark Mahoning Corp. 

A novel procedure for studying the competitive alkylation of benzene and toluene involved stirring a solution of 0.125 mole of each hydrocarbon and 0.05 mole of nitrosonium hexafluorophosphate in 50 g. of nitromethane at 25° and adding 11 solution of 0.025 mole of ethylamine in 20 g. of nitromethane over a period of 20 min. The results indicate the relative reactivities of toluene (T) and benzene (B) to... 

C-Alkylation Diethyl sulfate. Dimethyl sulfate. Dimethyl sulfoxide reagent (a). Methyl bromide. Methyl chloride. Nitrosonium hexafluorophosphate. Potassium r-butoxide. Sodium amide, Sodium ethoxide. Sodium 2-methyl-2-butoxide. Tetramethylurea. Tri-ethyloxonlum fluuruburate. Trimcthyloxonium fluurubomte. Trimethyloxonium 2,4,6-trlnltrobenzene lulfonale. Triiyliodium. 

The azepino[3,2,l-/i,/]indole skeleton has been formed by intramolecular Friedel-Crafts cycli-zation of l-(2-methylthioethanoyl)-4,5-dihydro-benz[ft]azepine with NCS <88JHC937>. Treatment of the hydrazinophosphonium tetrafluoroborate (119) with nitrosonium hexafluorophosphate in acetonitrile brings about ring contraction to phenanthridine together with a smaller amount of 5H-dibenz[c,c]azepine <82ZN(B)88l>. 

V-Nitrito-4-nitropyridinium salts are isomeric with the previously discussed W-nitropyridinium ions. Similarly, dimethylnitritosulfonium salts are isomeric with IV-nitrosulfonium ions, formed from nitronium salts and dimethyl sulfide. The nitro-onium salts are prepared from nitrosonium hexafluorophosphate with 4-nitropyridine-/V-oxide and dimethyl sulfoxide, respectively [131]. 

A further report has appeared on the use of trimethylsilyl iodide for ester cleavage/ Although lengthy reaction times are often required, yields of carboxylic acids are excellent. This reagent also offers the possibility of selectivity, as t-butyl and benzyl esters react rapidly at room temperature whereas other alkyl esters (Me, Et, Pr ) require temperatures at 50 °C for reaction to occur. A disadvantage of the reagent is that it will also attack ethers, ketals, and alcohols. An improvement of this method is the use of mixtures of phenyltrimethylsilane and iodine. Benzyl esters can be deprotected by oxidative cleavage with nitrosonium hexafluorophosphate. This method could be valuable as almost all non-hydrolytic methods for the removal of benzyl esters are reductive. 

Sodium superoxide in DMSO is a useful reagent for converting nitriles into amides. Isolated yields are above 70% for this reaction, which was unexpected as nitriles are inert to Na02 in other solvents. The mechanism is not completely understood. The Ritter-type synthesis of N-alkyl-amides from nitriles and alcohols can be improved by the addition of metal carbonyls to help stabilize the intermediate carbonium ions, and an alternative approach is to treat a nitrile with an alkyl halide and nitrosonium hexafluorophosphate. ... 

The notion that intervalence charge transfer occurs within the Ru=CH-Fc nanoparticles is further supported by NIR spectroscopy by using nitrosonium hexafluorophosphate (NOPF ) as the oxidizing reagent Figure 3.14 (a) shows the... 

While nitramines are formed from the reaction of secondary amines with nitronium salts the success of the reaction depends on the basicity of the amine (Equation 5.11). Thus, amines of low to moderate basicity are A-nitrated in good yields. The nitration of more basic amines is slow and the nitrosamine is often observed as a significant by-product, a consequence of the partial reduction of the nitronium salt to the nitrosonium salt during the reaction. Increased reaction temperature is also found to increase the amount of nitrosamine formed. The amine substrate is usually used in excess to compensate for the release of the strong mineral acid formed during the reactions. Both nitronium tetrafluoroborate and the more soluble hexafluorophosphate are commonly used for A-nitrations. Solvents like acetonitrile, methylene chloride, nitromethane, dioxane, sulfolane, ethyl acetate and esters of phosphoric acid are commonly used. 

Alternatively, the addition of the nitrosonium ion, generally as the tetrafluoroborate or hexafluorophosphate salt, provides a convenient synthetic route to nitrosyl complexes. Examples of such reactions include (18, 19)... 

The preliminary experiments were carried out using both nitronium tetrafluorophosphate in sulpholane and nitronium hexa-fluorophosphate in nitromethane. However, the products from these experiments had unexpectedly high concentrations of nitroso compounds this was traced to significant amounts of nitrosonium salts in the supposedly pure nitronium salts. A method was devised for the purification of nitronium hexafluorophosphate (see Experimental) which, from the raman spectra, was completely effective in removing this impurity. The same method did not work well for nitronium tetrafluoroborate and so all subsequent work was carried out using the hexafluorophosphate salt. 

Nitronium tetrafluoroborate, nitronium hexafluorophosphate and nitrosonium tetrafluoroborate were obtained from Ozark-Mahoning Company. 

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