Title of Invention

PROCESS AND PREPARATION OF NOVEL STRONG ACIDS

Abstract The present invention relates to acids of the general formula (1), RyPF6-y H+(1), where y =1,2 or 3, and in which the ligands R may be identical or different and R is a perfluorinated CH1-8 alkyl or aryl group or R is a partially fluorinated C1-8 alkyl or aryl group, in which some of the F or H may have been substituted by chlorine. The present invention furthermore relates to a process for the preparation of the acids according to the invention, to salts comprising a cation and the anion of the acid according to the invention, and to a process for the preparation of the salts. The invention furthermore relates to the use of the acids and salts according to the invention.
Full Text The present invention relates to acids of the general formula [1]
where
y=1,2 or 3,
and in which
the ligands R may be identical or different, and
R is a perfluorinated C1-8-alkyl or aryl group or R is a partially fluorinated
C1-8-alkyl or aryl group in which some of the F or H may have been
substituted by chlorine.
The present invention furthermore relates to a process for the preparation of the
acids according to the invention, to salts comprising a cation and the anion of one
of the acids according to the invention, and to a process for the preparation of the
salts. The invention furthermore relates to the use of the acids and metal salts
according to the invention.
Hexafluorophosphoric acid, HPF6, is used as a catalyst in organic chemistry or as
a starting compound for the preparation of various salts. In the industry,
hexafluorophosphoric acid is obtained by reaction [1] of phosphorus pentoxide
and anhydrous hydrofluoric acid.
P4O10 + 24 HF -> 4 HPF6 + 10H2O
[1]
Disadvantages of this process are the toxicity and the risk associated with
handling the starting compound hydrogen fluoride, and the highly exothermic
evolution of heat in the reaction.

Hexafluorophosphoric acid is commercially available as a 65% by weight aqueous
solution. The solution is unstable at higher concentrations. Pure hexafluorophosphoric
acid can be prepared in liquid sulfur dioxide, but is unstable at room temperature
(D.E.C. Colbridge, Phosphorus. An Outline of chemistry, Biochemistry and
Technology (Second Edition) Elsevier Scientific Publishing Comp. Amsterdam-
Oxford-New York, 1980). The poor stability of highly concentrated hexafluorophosphoric
acid solutions limits the potential uses of this acid as a catalyst. In addition,
the coordination of the proton with the phosphorus hexafluoride anion reduces
the proton activity of this acid.
The present invention therefore has the object of providing fluorophosphoric acid
compounds which do not have the disadvantages of the prior art.
This object is achieved by an acid of the general formula [I]
where
y= 1,2 or 3,
and in which
the ligands R may be identical or different, and
R is a perfluorinated C1-8-alkyl or aryl group or R is a partially fluorinated C1-8-
alkyl or aryl group in which some of the F or H may have been substituted by
chlorine.
The perfluorinated and the partially fluorinated alkyl or aryl groups R may be in the
form of chain or ring structures.

Preference is given to acids in which at least one group R is a perfluorinated n-, iso-
or tert-butyl group or a pentafluorophenyl group and is particularly preferably a
pentafluoroethyl group.
Preference is furthermore given to acids in which y = 2 or 3. Particular preference is
given to acids in which y = 3.
Particular preference is given to the acids according to the invention trifluorotris-
(pentafluoroethyl)phosphoric acid, trifluorotris(nonafiuoro-n-butyl)phosphoric acid,
trifluorotris(heptafluoro-n-propyl)phosphoric acid, tetrafluorobis(nonafluoro-n-butyl)-
phosphoric acid, pentafluoro(nonafluoro-n-butyl)phosphoric acid and tetrafluorobis-
(heptafluoro-i-propyl)phosphoric acid.
For the nomenclature of fluorinated phosphoric acids, reference is made to the
IUPAC nomenclature (A Guide to IUPAC Nomenclature of Organic Compounds.
Recommendations, by R. Panico, W.H. Powell and Jean-Claude Richer, Blackwell
Science, 1993).
The acids according to the invention have the advantage over the fluorophosphoric
acids known hitherto of being easy to prepare, having high proton activity and being
stable at room temperature in highly concentrated solution.
The present invention furthermore relates to a process for the preparation of the
acids according to the invention in which a perfluoroalkylphosphorane is reacted with
hydrogen fluoride in the presence of a suitable solvent and/or proton acceptor.
The preparation of perfluoroalkylphosphoranes as starting compounds for the process
according to the invention is familiar to the person skilled in the art from the
prior art, for example from German Patent Application DE 19 846 636 A1, which is
incorporated herein by way of reference and is thus regarded as part of the disclosure.

Suitable solvents and/or proton acceptors for the processes according to the invention
are preferably compounds having one, two or more of the following atoms: O, N,
S, P, Se, Te and As.
Preference is given to water, alcohols, ethers, sulfides, amines, phosphines, carbox-
ylic acids, esters, glycols, polyglycols, polyamines, polysulfides or mixtures of at least
two of these solvents and/or proton acceptors.
Particularly preferred solvents and/or proton acceptors are water, methanol, ethanol,
acetic acid, dimethyl ether, diethyl ether, dimethyl carbonate, dimethyl sulfide,
dimethylformamide, triethylamine or triphenylphosphine, or mixtures of at least 2 of
these compounds.
The concentration of hydrogen fluoride in the suitable solvent is preferably greater
than 0.1% by weight of HF, particularly preferably greater than 5% by weight of HF
and very particularly preferably greater than 10% by weight and most preferably
greater than 20% by weight, but less than 100% by weight, of HF.
In a preferred embodiment, the reaction of the perfluoroalkylphosphorane in the
processes according to the invention is carried out at a temperature of from -50 to
+100°C, preferably at a temperature of from -35 to +50°C, particularly preferably at
from 0 to 25°C.
By means of the process according to the invention, acids of the general formula [I]
are readily accessible in high yields.
The present invention also relates to solutions of the acids according to the invention
which have a concentration of greater than 2% by weight, preferably greater than
20% by weight, particularly preferably greater than 70% by weight, most preferably
greater than 80% by weight, of the acid in a suitable solvent.
The solutions according to the invention, in particular in the high concentration
ranges, enable proton activities which can only be achieved with difficulty with solutions
of other fluorophosphoric acids. This is particularly advantaqeous on use of the

acids according to the invention in highly concentrated form, for example as catalyst
in a reaction mixture. A highly concentrated solution also avoids undesired dilution of
reaction mixtures.
The present invention furthermore relates to salts of the general formula [II]

where
Mm+ is a monovalent, divalent or trivalent cation,
m = 1, 2 or 3
and y = 1, 2 or 3,
and in which
the ligands R may be identical or different, and
R is a perfluorinated C1-8-alkyl or aryl group or R is a partially fluorinated C1-8-
alkyl or aryl group in which some of the F or H may have been substituted by
chlorine.
The cation Mm+ can be a metal cation or an organic cation.
Suitable organic cations are known to the person skilled in the art and are described,
for example, in German Patent Application DE 10109032.3 on pages 4 to 6. This literature
is incorporated herein by way of reference and is thus regarded as part of the
disclosure.
The salts of the general formula [II] preferably contain an Li, Zn, Mg, Cu, Ag, ammonium,
phosphonium, oxonioum, sulfonium, arsonium, tropilium, a a nitryl cation, a
nitrosyl cation or a tris(dialkylammino)carbonium cation.
An advantage of the salts according to the invention is their good solubility in organic
solvents.

In a preferred embodiment, these salts are prepared by a process in which an acid
according to the invention is reacted in a suitable solvent with a salt of the general
formula [III]

where
Mm+ is a monovalent, divalent or trivalent cation,
A is a basic or neutral anion or a mixture of basic anions or a mixture of at
least one basic and at least one neutral anion,
and m = 1, 2 or 3,
or with metals, metal hydrides, metal oxides or metal hydroxides.
The process is preferably carried out using salts of the formula [III] which contain at
least one carbonate, chloride, fluoride, formate, acetate or trifluoroacetate anion.
The process is preferably carried out using anions which form readily volatile acids,
such as, for example, hydrochloric acid, formic acid or acetic acid.
In the process, the metals employed are preferably Li, Na, K, Rb, Mg, Cs, Ca, Sr, Ba,
Sc, Y, Yb, La, Al, In, Cd and/or Zn, the oxides employed are preferably Li2O, Na2O,
K2O, MgO, CaO, SrO, BaO, Sc2O3, Y2O3, Yb2O3, La2O3, AI2O3, CdO, ZnO, CuO, FeO
and/or Fe2O3, the hydroxides employed are preferably LiOH, NaOH, KOH, RbOH,
CsOH, Mg(OH)2, Ca(OH)2, Sr(OH)2, Ba(OH)2, Cd(OH)2, Zn(OH)2, Sc(OH)3, AI(OH)3
and/or Cu(OH)2, and the hydrides employed are preferably LiH, NaH, CaH2, YH3
and/or AIH3.
The process for the preparation of the salts according to the invention is simple to
carry out and offers high yields.

In addition, the present invention relates to the use of one of the salts according to
the invention as catalyst, as phase-transfer catalyst, as solvent, in particular as ionic
liquid, or as conductive salt in the electrolytes of various electrochemical devices.
The person skilled in the art understands an "ionic liquid" to be organic compounds
having an ionic structure and a low melting point, for example N,N-dialkylimidazolium
salts [C.E. Song, E.J. Roh, Chem. Comm. (Camebridge) 2000, 10, pp. 837-838;
J. Howarth, Tetrahedron Lett. 41 (2000) 34, pp. 6627-6629; C.E. Song, C.E. Oh,
E.J. Roh, D.J. Choo, Chem. Comm. (Camebridge) 2000, 18, pp. 1743-1744).
The present invention also relates to the use of an acid according to the invention as
catalyst in the preparation of organic compounds.
The acids according to the invention are particularly suitable as replacement for the
acids HPF6 and/or HBF4 in chemical reactions.
The acids and/or salts according to the invention are preferably used in one of the
following processes:
Processes for the
- preparation of photosensitive polymers [CA (Chemical Abstracts) 110: 15956e],
- preparation of dihydroxydiaryl compounds [CA 110: 94679t],
- surface treatment of metals [CA 110:139975e],
- preparation of electrically conductive aniline polymers [CA 110: 155067r],
- preparation of carboxylic acids and carboxylic acid esters [CA 110: 233613g],
- preparation of high-molecular-weight diazonium compounds [CA 110: 87472n],
- preparation of epoxy resins (CA 111:135490r],
- preparation of electrically conductive materials from amine-like compounds [CA
112:46758n],
- preparation of octadienols [CA 112: 98016p],
- carboamination or carboamidation of olefins [CA 112: 161007d],
- isomerisation of butenes [CA 112: 157653u],
- preparation of electrically conductive polyalkoxythiophenes [CA 115: 50551 u],

- desulfuration of oil and effluent [CA 116: 261878q],
- preparation of triglycidyltrimethylolalkane-based compositions [CA 117: 92344a],
- preparation of polymers from styrene and carbon monoxide [CA 117:172290v],
- preparation of organic salts for the storage of information [CA 117:17381g],
- production of information carriers having good light resistance [CA 115:
267063w],
- preparation of silicon support materials for catalysts [CA 117: 74989k],
- polymerisation of pyrrole derivatives [CA 117: 70577b],
- copolymerisation of carbon monoxide and an olefinically unsaturated compound
[CA118:7520h],
- preparation of electrically conductive polymers [CA 118:137707k],
- preparation of magnetic contrast agents [CA 118: 299355x],
- preparation of polymer coatings [CA 119: 54608y],
- removal of oxide layers on stainless steel [CA 119: 77272y],
- synthesis of methyl tert-butyl ether [CA 119: 202992m],
- preparation of cycfic sulfonium salts containing 5-7 carbons [CA 119: 249826a],
- preparation of cyclosiloxanes [120: 108008u],
- refining of heavy oils and bitumen [CA 120: 195633k],
- treatment of aluminium compounds [CA 120: 283104u],
- preparation of quaternary pyridinium or anilinium salts [CA 121: 9165g],
- copolymerisation of olefins and carbon monoxide [CA 121:10209f],
- preparation of aromatic hydroxylic compounds [CA 121:133684q],
- preparation of acetic ester derivatives [CA 121:157308w],
- preparation of resin from dialkenylbenzene and polyarylamines [CA 122: 70050c],
- preparation of substituted pyrrolopyrimidin-4-ones [CA 122: 314562q],
- recovery of petroleum [CA 122: 295102w],
- use as non-aqueous battery electrolytes [CA 122:118595j],
- preparation of stable methyl cations [CA 124: 288639q],
- preparation of cyclic sulfonium salts [CA 125:114470h],
- preparation of optical storage materials [CA 125:127895a],
- preparation of conjugated fluoropyridinium salts [CA 125:119500c],
- preparation of iridium/diphosphine complexes [CA 126: 226760e],
- asymmetric hydrogenation of imines [CA 126: 225097g],
- hydroformylation of unsaturated compounds [CA 126: 225032g],

- synthesis of polymers [CA 126: 104554v],
- preparation of polymers from polycycloolefins with silyl groups [CA 127:
110414m],
- preparation of ruthenium catalysts [CA 127: 83071p],
- preparation of ibuprofen [CA 127: 318741y],
- preparation of cyclohexadienyl compounds [CA 126: 212225x],
- copolymerisation of olefins [CA 126: 199931c],
- preparation of inorganic methylimidazolinium salts [CA 128:167423p],
- preparation of SiCO and SiC ceramic fibres [CA 128: 234151 p],
- preparation of thermoprint materials [CA 128: 210892e],
- preparation of polymers [CA 129: 317091 r],
- preparation of aziridine-polyether compounds [CA 131: 35901 v],
- preparation of dicarboxylic acid diesters [CA 131: 199417t],
- hydroxylation of aromatic hydrocarbons [CA 129: 218223d],
- preparation of carboxylic acids and carboxylic acid esters [CA 129: 216347y],
- pretreatment of lithographic printing plates [CA 129:195815g].
The invention is explained below with reference to examples. These examples serve
merely to explain the invention and do not restrict the general inventive idea.
The process according to the invention can be used to prepare, for example, trifluoro-
tris(perfluoroalkyl)phosphoric acids in virtually quantitative yield by reaction of
difluorotris(perfluoroalkyl)phosphoranes with hydrogen fluoride in suitable solvents.
Surprisingly, this yield is virtually unimpaired by hydrolysis.
The process according to the invention can be used, for example, to prepare a highly
concentrated aqueous solution of trifluorotris(pentafluoroethyl)phosphoric acid within
a few minutes by reaction of difluorotris(pentafluoroethyl)phosphorane with 18.3% by
weight aqueous HF. The reaction proceeds in accordance with the reaction equation
[2]:
(C2F5)3PF2 + HF + 5 H2O -> [(C2F5)3PF3]H+ 5 H2O

The resultant solution has a concentration of 83.2% by weight and is stable for a
number of weeks at room temperature.
Acid concentrations of less than 83.2% by weight can also be prepared in this way,
for example by dilution with a suitable solvent or by reaction of a phosphorane with
more highly diluted hydrogen fluoride solution.
However, the reaction of phosphoranes with more-dilute aqueous hydrogen fluoride
solutions, for example 2% by weight, take more time. In the case of more highly
diluted aqueous hydrogen fluoride solutions, firstly an adduct of water and phosphorane
is formed, and this is then slowly converted into the more stable product.
The rate of conversion of the adduct into the product is temperature-dependent. At
room temperature, the conversion in accordance with reaction [2] in 2% by weight
hydrogen fluoride solution takes 2 days. At -21 °C and under the same concentration
ratios, only 30% of the adduct has converted into trifluorotris(pentafluoroethyl)phos-
phoric acid within six days.
On reaction of the phosphorane in an ice bath in accordance with reaction equation
[2] with a 4.3% by weight aqueous hydrogen fluoride solution, a mixture of phos-
phorane/water adduct and trifluorotris(pentafluoroethyl)phosphoric acid in the ratio
1:2 is formed within 2-3 minutes.
The reaction can be carried out at atmospheric pressure or superatmospheric pressure,
if desired also under a protective-gas atmosphere.
Trifluorotris(pentafluoroethyl)phosphoric acid can exist in two different conformations,
the meridional conformation and the facial conformation. The two structures exist in
equilibrium. This equilibrium is dependent on the temperature and the hydrogen fluoride
concentration in water during reaction of the starting materials. Initially, the
meridional structure is formed, which then achieves an equilibrium with the facial
structure.
The person skilled in the art understands that the proton in the strong acids according
to the invention is in the form of a complex with the respective solvent. In the for-

mulation of the formulae in the examples, the complex of proton and solvent has
therefore not been formulated out.
The complete disclosure content of all applications, patents and publications mentioned
above and below and of the corresponding application DE 101 30 940.6, filed
on 27.06.2001, is incorporated into this application by way of reference.
Even without further comments, it is assumed that a person skilled in the art will be
able to utilise the above description in the broadest scope. The preferred embodiments
and examples should therefore merely be regarded as descriptive disclosure
which is absolutely not limiting in any way.
All NMR spectra were measured on a Bruker WP 80 SY spectrometer (1H: 80 MHz,
19F: 75.47 MHz).

Examples
Example 1
3.74 g of water were added to 3.14 g of a 40% by weight aqueous hydrofluoric acid
(62.8 mmol of HF) (in total 312.1 mmol of water) in an FEP (fluoroethylene polymer)
flask. After this mixture had been cooled in an ice bath, 26.55 g (62.3 mmol) of
difluorotris(pentafluoroethyl)phosphorane were added over the course of 2 minutes
while stirring using a magnetic stirrer. All the phosphorane had dissolved within 3
minutes, and a colourless, clear solution of aqueous acid [(C2F5)3PF3] - H + had
formed. 33.4 g of an 83.2% by weight trifluorotris(pentafluoroethyl)phosphoric acid
solution were prepared in virtually quantitative yield.
The compound conforms to the formula: [(C2F5)3PF3]-H+ -5H2O.
The solution was analysed by 19F NMR spectroscopy. The spectra were measured
using an FEP tube with an acetone-D6 film as external lock and CCl3F as external
reference.
19F NMR, 5, ppm: -44.03 dm (PF); -80.61 m (CF3); -82.47 m (2CF3); -88.99 dm (PF2);
-115.36 dm (3CF2); J1P.F=889 HZ; J1P.F=907 HZ; J2P.F=92 HZ.
These signals belong to the meridional structure of the acid [(C2F5)3PF3]-H+-5H2O.
Within 2 days, a new doublet formed in the 19F NMR spectrum at -67.41 ppm;
J1P,F=786 Hz (PF3 group), which can be assigned to the facial structure of the acid
E(C2F5)3PF3]-H+ -5H2O. No further changes were observed during storage at room
temperature over the next 3 weeks. The 83.2% by weight acid formed an equilibrium
mixture of about 90% of the meridional conformation and 10% of the facial conforma-
tion of the acid at room temperature.
Example 2
2.24 g of water were added to 1.88 g of a 40% by weight aqueous hydrofluoric acid
solution (37.6 mmol of HF) (in total 186.8 mmol of water) in an FEP flask. 15.88 g
(37.3 mmol) of difluorotris(pentafluoroethyl)phosphorane were added to the aqueous

HF solution at room temperature over the course of 3 minutes while stirring the reaction
mixture using a magnetic stirrer. Due to the exothermic reaction, temperatures of
up to 50°C were reached, while the phosphorane dissolved. 20.0 g of a colourless,
clear solution of [(C2F5)3PF3]-H+ in water with a concentration of 83.2% by weight
were formed in virtually quantitative yield.
The solution was analysed by 19F NMR spectroscopy. The spectra were measured
using an FEP tube with an acetone-D6 film as external lock and CCl3F as external
reference.
19F NMR (meridional conformation), 8, ppm: -44.46 dm (PF); -81.05 m (CF3); -82.85
m (2CF3); -89.54 dm (PF2); -115.74 dm (3CF2); J1P.F= 889 Hz; J1P.F= 905 Hz;
J2P.F=93 Hz.
19F NMR (facial conformation), d, ppm: -67.82 dm (PF3); J1P.F= 784 Hz. Other signals
of the facial conformation overlapped with the signals of the meridional conformation.
The spectra show that in this case both conformations of the acid, both the meridional
and the facial conformation, are formed at the time of preparation of the solution.
Example 3
10.57 g of water were added to 3.91 g of a 40% by weight aqueous hydrofluoric acid
solution (78.2 mmol of HF) (in total 716.8 mmol of water) in an FEP flask. After this
mixture had been cooled in an ice bath, 33.34 g (78.2 mmol) of difluorotris(penta-
fluoroethyl)phosphorane were added over the course of 3 minutes while stirring using
a magnetic stirrer. All the phosphorane dissolved within this time, and a clear solution
of [(C2F5)3PF3]- H+ was formed. 47.8 g of aqueous trifluorotris(pentafluoroethyl)-
phosphoric acid (I) in a concentration of 73.0% by weight were obtained in quantitative
yield.
19F NMR (CCbF - external reference): -44.45 dm (PF); -80.84 m (CF3); -82.57 m
(2CF3); -89.13 dm (PF2); -115.75 dm (3CF2); J1P,F=889 HZ; J1P,F= 909 Hz; J2P,F=
92 Hz.

The signals shown belong to the meridional structure of the acid [(C2F5)3PF3]-H+ and
exhibited no changes in the spectrum within 5 days. The acid [(C2F5)3PF3]-H+ thus
preferentially exhibits the meridional conformation in the present concentration at
room temperature.
Example 4
12.46 g of water were added to 1.51 g of a 40% by weight aqueous hydrofluoric acid
solution (30.2 mmol of HF) (in total 741.7 mmol of water) in an FEP flask. After this
mixture had been cooled in an ice bath, 12.74 g (29.9 mmol) of difluorotris(penta-
fluoroethyl)phosphorane were added over the course of 3 minutes while stirring using
a magnetic stirrer. All the phosphorane dissolved in this period, and 26.7 g of a
colourless, clear solution of the acid were obtained in virtually quantitative yield.
The 19F NMR spectrum showed the presence of two forms of hexacoordinated phosphorus.
The first form is a complex of difluorotris(pentafluoroethyl)phosphorane with
water:
19F NMR (CCl3F - external reference): -80.39 m (CF3); -81.31m (2CF3); -89.19 dm
(PF2); -113.78 dm (3CF2); -164.59 s (H3O+HF) J1P.F = 846 Hz ; J2P.F =89 Hz.
The second form is the usual meridional conformation of trifluorotris(pentafluoro-
ethyl)phosphoric acid [(C2F5)3PF3]-H+.
19F NMR (CCl3F - external reference): -44.60 dm (PF); -80.81 m (CF3); -82.49 m
(2CF3); -89.34 dm (PF2); -115.96 dm (3CF2); J1P.F = 889 Hz ; J1P.F = 884 HZ; J2P.F =
95 Hz.
Within 4 days of storage at room temperature, the 19F NMR spectrum only showed
the presence of the meridional conformation of trifluorotris(pentaftuoroethyl)phos-
phoric acid [(C2F5)3PF3]- H+ in solution.
Example 5

29.60 g of water were added to 1.47 g of a 40% by weight aqueous hydrofluoric acid
solufon (29.4 mmol of HF) (in total 1691.6 mmol of water) in an FEP flask. After this
mixture had been cooled in an ice bath, 12.47 g (29.3 mmol) of difluorotris(penta-
fluoroethyl)phosphorane were added over the course of three minutes while stirring
using a magnetic stirrer. All the phosphorane dissolved within this period, and a
colourless, clear solution of 43.5 g was prepared.
The 19F NMR spectrum showed that in this case principally the aqueous adduct is
formed directly on addition of the phosphorane.
19F NMR (CCl3F - external reference): -79.49 m (CF3); -80.74 m (2 CF3);
-88.60 dm (PF2); -113.35 dm (3CF2); -162.54 s (H3O+ HF) J1PfF=842 HZ;
-J2P, F=89 Hz.
Within five days at room temperature, this adduct was converted completely into
tris(pentafluoroethyl)trifluorophosphoric acid [(C2F5)3PF3] -H1". This was confirmed by
19F NMR spectroscopy.
Example 6
5.64 g (122.3 mmol) of dimethyl ether were cooled to -35°C in an FEP flask using an
ethanol bath. In succession, firstly 1.42 g (71.0 mmol) of hydrogen fluoride (HF) were
slowly added to the reaction mixture and subsequently 30.25 g (71.0 mmol) of
cHfluorotris(pentaftuoroethyl)phosphorane were added over the course of five minutes
while the reaction mixture was stirred using a magnetic stirrer. When the phosphorane
had dissolved and the reaction mixture had warmed to room temperature,
37.3 g of a colourless, clear solution were obtained.
This solution was analysed by 19F NMR spectroscopy. The spectra were measured
using an FEP tube with an acetonitrile-D3 film as external lock and CCl3F as internal
reference.
The 19F NMR spectrum showed that in this case the acid [(C2F5)3PF3]-H+ is preferentially
formed with the meridional structure.

19F NMR of the meridional conformation: -43.58 dm (PF); -80.19 m (CF3);
-81.90 m (2CF3); -87.03 dm (PF2); -115.51 dm (3CF2); J1P,F=888 HZ; J1P.F=894 HZ;
J2P, F=94 Hz.
Within three days, the concentration of the facial conformation of the acid
[(C2F5)3PF3]~ H+ in the mixture increased.
19F NMR spectrum of the facial conformation: -66.12 dm; J1P.F=798 HZ (PF3 group).
Other signals of the facial conformation overlapped with the signals of the meridional
conformation.
No further changes in the 19F NMR spectra were observed within five weeks during
storage at room temperature.
Example 7
6.04 g (81.5 mmol) of dry diethyl ether in an FEP flask were cooled by means of an
ice bath. While stirring using a magnetic stirrer, firstly 0.92 g (45.9 mmol) of hydrogen
fluoride (HF) was slowly added to the diethyl ether and then 18.67 g (43.8 mmol) of
difluorotris(pentafluoroethyl)phosphorane were added over the course of 5 minutes.
After dissolution of the phosphorane within one to two minutes and warming of the
reaction mixture to room temperature, 25.6 g of a colourless, clear solution were
formed.
This solution was analysed by 19F NMR spectroscopy. The spectra were measured
using an FEP tube with an acetonitrile-D3 film as external lock and CCl3F as internal
reference.
The 19F NMR spectrum showed that the acid [(C2F5)3PF3]" H+ is formed in two con-
formations.
19F NMR of the meridional conformation (approximately 85 mol%); -43.68 dm (PF);
-80.00 m (CF3); -81.71 m (2CF3); -86.93 dm (PF2); -115.31 dm (3CF2); J1P, F=890 HZ;
J1P,F=897HZ; J2P,F=92HZ.

19F NMR spectaim of the facial form (approximately 15 mol%): -67.37 dm;
J1P, F=793 Hz (PF3 group). Other signals of the facial conformation overlapped with
the signals of the meridional conformation.
No changes in the 19F NMR spectrum were observed within two months on storage
at room temperature.
Example 8
3.33 g (103.9 mmol) of methanol in an FEP flask were cooled using an ice bath.
While stirring using a magnetic stirrer, firstly 0.91 g (45.5 mmol) of hydrogen fluoride
(HF) was slowly added to the methanol and 18.05 g (42.4 mmol) of difluorotris(penta-
fluoroethyl)phosphorane were added to the reaction mixture over the course of a
further five minutes. After dissolution of the phosphorane and warming of the reaction
mixture to room temperature, 22.2 g of a colourless, clear solution were obtained.
This solution was analysed by 19F NMR spectroscopy. The spectra were measured
using an FEP tube with an acetonitrile-D3 film as external lock and CCl3F as internal
reference.
The 19F NMR shows that in this case the acid [(C2F5)3PF3]-H+ is formed in two conformations.
19F NMR of the meridional conformation (approximately 85 mol%): -43.80 dm (PF);
-80.50 m (CF3); -81.93 m (2CF3); -87.50 dm (PF2); -114.93 dm (3CF2); J1P.F=887 HZ;
J2P. F=95 Hz.
19F NMR spectrum of the facial conformation (approximately 15 mol%): -66.44 dm;
J1P.F=780 Hz. (PF3 group). Other signals of the facial form overlapped with the signals
of the meridional form.
No changes in the 19F NMR spectrum were observed within one month on storage at
room temperature.
Example 9

3.02 g (48.8 mmol) of dimethyl sulfide (CH3)2S in an FEP flask were cooled by means
of an ice bath. While stirring using a magnetic stirrer, firstly 0.98 g (49.0 mmol) of
hydrogen fluoride (HF) and subsequently, over the course of five minutes, 20.88 g
(49.0 mmol) of difluorotris(pentafluoroethyl)phosphorane were added to the dimethyl
sulfide. When all the phosphorane had been added, the reaction mixture hardened
completely. After additional mechanical stirring and drying of the reaction mixture at
room temperature in a stream of argon protective gas, 23.9 g of a colourless, solid
material were obtained.
0.4 g of this material was dissolved in acetonitrile-D3, and this solution was analysed
by 19F NMR spectroscopy. CCl3F was used as internal reference.
The 19F NMR spectrum showed that in this case the acid [(C2F5)3PF3]- H+ is formed in
the meridional conformation.
19F NMR: -43.54 dm (PF); -79.66 m (CF3); -81.25 m (2CF3); -86.83 dm (PF2);
-115.28 dm (3CF2); J1P. F=889 HZ; J1P, F=906 HZ; J2P, F=92 HZ.
Example 10
3.23 g (12.3 mmol) of triphenylphosphine (Ph3P) in an FEP flask were cooled to
-25°C in an ethanol/dry ice bath. While the reaction mixture was stirred using a magnetic
stirrer, firstly 0.66 g (33.0 mmol) of hydrogen fluoride (HF) was slowly added to
the triphenyfphosphine and then 5.25 g (12.3 mmol) of difluorotris(pentafluoroethyl)-
phosphorane were added over the course of a further five minutes. When all the
phosphorane had been added, the reaction mixture hardened completely. After
additional mechanical mixing and drying of the reaction mixture at room temperature
under a stream of argon protective gas, 8.8 g of a pale-yellow solid were obtained.
0.4 g of this material was dissolved in acetonitrHe-D3, and this solution was analysed
by 19F NMR spectroscopy. CCl3F was used as internal reference.
The 19F NMR spectrum showed that in this case the acid [(C2F5)3PF3]" H+ as a complexes
with triphenylphosphine is formed in the meridional conformation.

19F NMR: -43.65 dm (PF); -79.75 m (CF3); -81.34 m (2CF3); -86.99 dm (PF2);
-115.45 dm (3CF2); J1P.F=889 HZ; J1P. F=906 HZ; J2P.F=92 HZ.
A small signal of residual HF is visible in the 19F NMR spectrum (-181.75 ppm).
1H NMR: 7.8 m (Ph3PH+)
Example 11
1.71 g (23.4 mmol) of dimethylformamide, HC(O)N(CH3)2, in an FEP flask were
cooled to -25°C using an ethanol/dry ice bath. While stirring using a magnetic stirrer,
firstly 0.566 g (28.3 mmol) of hydrogen fluoride (HF) was slowly added to the
dimethylformamide and then 9.92 g (23.3 mmol) of diftuorotris(pentafluoroethyl)-
phosphorane were added at 0°C over the course of five minutes. When all the phos-
phorane had been added, the reaction mixture was warmed to room temperature.
12.2 g of a high-density, virtually solid, white material were produced.
Small amounts of this material were dissolved in dimethylformamide and in aceto-
nitrile-D3, and these solutions were analysed by 19F and 1H NMR spectroscopy.
CCl3F and TMS were used as internal reference.
The 19F NMR spectrum showed that in this case the acid [(C2F5)3PF3]-H+ is formed in
the meridional conformation.
19F NMR (solvent: acetonitrile-D3): -43.64 dm (PF); -79.76 m (CF3);
-81.35 m (2CF3); -87.08 dm (PF2); -115.35 dm (3CF2); J1P.F=889 HZ; J1P. F=906 HZ;
J2P, F=90 Hz.
A small signal of residual hydrogen fluoride was again observed in the 19F NMR
spectrum (-182.30 ppm).
1H NMR (solvent: acetonitrile-D3): 3.12 s (CH3); 3.27 s (CH3); 8.19 s (CH); 10.97 s
(H+).

19F NMR (solvent: dimethylformamide): -43.88 dm (PF); -79.76 m (CF3);
-81.35 m (2CF3); -87.08 dm (PF2); -115.35 dm (3CF2); J1P.P=889 HZ; J1P,F=906 HZ;
J2P, F=90 Hz.
A small signal of residual hydrogen fluoride was again observed in the 19F NMR
spectrum (-182.30 ppm).
Example 12
4.92 g (81.9 mmol) of acetic acid, CH3COOH, in an FEP flask were cooled by means
of an ice bath. While stirring using a magnetic stirrer, firstly 0.424 g (21.2 mmol) of
hydrogen fluoride (HF) was slowly added to the acetic acid and then 8.83 g
(20.7 mmol) of difluorotris(pentafluoroethyl)phosphorane were added over the course
of five minutes. After the phosphorane had dissolved and the reaction mixture had
been warmed to room temperature, 14.17 g of a colourless, clear solution were
obtained.
This solution was analysed by 19F NMR spectroscopy. The spectra were measured
using an FEP tube with an acetone-D6 film as external lock and CCl3F as external
reference. In this example, the 19F NMR spectrum shows that the acid
[(C2F5)3PF3]~ H+ is preferentially formed in the meridional structure.
19F NMR of the meridional form: -44.65 dm (PF); -80.94 m (CF3); -82.58 m (2CF3);
-88.59 dm (PF2); -116.16 dm (3CF2); J1P, F=890 HZ; J2P, F=92 HZ.
1H NMR (acetonitrile-D3 film): 2.43 s (CH3); 12.43 s (H+).
Example 13
0.077 g of a 40% by weight aqueous hydrofluoric acid solution (1.54 mmol of HF)
was mixed with 0.124 g of water (in total 9.44 mmol of water) in an FEP flask. While
stirring using a magnetic stirrer, this mixture was cooled in an ice bath, and 0.836 g
(1.15 mmol) of difluorotris(nonafluoro-n-butyl)phosphorane was added over the
course of two minutes. All the phosphorane had dissolved within a further five
minutes, and a colourless, clear solution of [(C4F9)3PF3]' H+ in water had formed.

1.037 g of this solution of trifluorotris(nonafluoro-n-butyl)phosphoric acid having a
concentration of 83.6% by weight in water were obtained in virtually quantitative
yield.
The solution was analysed by 19F NMR spectroscopy. The spectra were measured
using an FEP tube with an acetone-D6 film as external lock and CCl3F as external
reference.
19F NMR, d, tpm: -44.91 dm (PF); -82.47 m (3CF3); -87.29 dm (PF2);
-112.32 m (3CF2); -120.15 m (1CF2); -122.52 m (2CF2); -126.24 m (3CF2);
J1P.F=904HZ;
J1P.F=929HZ.
Example 14
0.272 g (3.67 mmol) of dried diethyl ether in an FEP flask was cooled using an ice
bath. While stirring using a magnetic stirrer, firstly 0.043 g (2.15 mmol) of hydrogen
fluoride (HF) was slowly added to the diethyl ether and then 0.864 g (1.19 mmol) of
difluorotris(nonafluoro-n-butyl)phosphorane was added over the course of five
minutes. During the addition, all the phosphorane dissolved, and 1.17 g of a colourless,
clear solution were prepared.
The solution was analysed by 19F NMR spectroscopy. The spectra were measured
using an FEP tube with an acetonitrile-d6 film as external lock and CCl3F as internal
reference.
The 19F NMR spectrum confirmed that the acid [(C4F9)3PF3]- H+ (III) is formed.
19F NMR, d, ppm: -44.17 dm (PF); -81.37 m (3CF3); -84.76 dm (PF2);
-112.00 m (3CF2); -119.18 m (1CF2); -121.32 m (2CF2); -125.15 m (3CF2);
J1 P. F=907 Hz; J1 P. F=939 Hz.

Example 15
0.68 g of an 18.3% by weight aqueous hydrofluoric acid solution (6.22 mmol of HF)
was slowly added at 0°C to 3.27 g (6.22 mmol) of trifluorobis(nonafluoro-n-butyl)-
phosphorane while stirring using a magnetic stirrer. All the phosphorane had
dissolved within three minutes, and a colourless, clear solution of H+ [(n-C4F9)2PF4]-
in water formed. The yield was 3.95 g of a solution of tetrafluorobis(nonafluoro-n-
butyl)phosphoric acid having a concentration of 85.9% by weight in water in virtually
quantitative yield. The product conforms to the formula H+[(C4F9)2PF4]-5 H2O.
The solution was analysed by 19F NMR spectroscopy. The spectra were recorded
using an FEP sample tube inside an NMR tube having a 5 mm thick wall, with an
acetone-D6 film being used as external lock and CCl3F in the film as reference.
19F NMR spectrum, d, ppm: - 70.72 dm (PF4); -81.191 (2CF3); -115.15 dm (2CF2);
-122.58 m (2CF2); -124.77t (2 CF2); J1P. F= 958 Hz; J2P.F= 105 Hz;
J4F.F=9.3HZ; J4F.F=16.4Hz;
Example 16
0.713 g (1.67 mmol) of trifluorobis(heptafluoro-i-propyl)phosphorane was slowly
added (over the course of 2 minutes) at 0°C to 0.217 g of a 20.8% by weight,
aqueous hydrofluoric acid solution (2.26 mmol of HF) while stirring using a magnetic
stirrer. During this time, all the phosphorane dissolved, and a colourless, clear solution
of tetrafluorobis(heptafluoro-i-propyl)phosphoric acid, H+ [(i-C3F7)2PF4]-, in water
formed.
The solution was analysed by 19F NMR spectroscopy. The spectra were recorded
using an FEP sample tube inside an NMR tube having a 5 mm thick wall, with an
acetone-D6 film being used as external lock and CC1 3F in the film as reference.
19F NMR spectrum, d, ppm: -58.37 dm (PF4); -71.23 m (4CF3); -182.72 dm (2CF);
J1P, F= 955 Hz; J2P. F= 78.4 Hz.
The signal of the excess HF was measured at 168.89 ppm in the 19F NMR spectrum.

Example 17
6.57 g (36.7 mmol) of triethylene glycol dimethyl ether (triglyme) in an FEP flask were
cooled by means of an ice bath. Firstly 0.74 g (37.0 mmol) of hydrogen fluoride (HF)
was slowly added to the triglyme and then, over the course of five minutes, a further
14.90 g (35.0 mmol) of difluorotris(pentafluoroethyl)phosphorane were added while
stirring the reaction mixture using the magnetic stirrer. After the reaction mixture had
been stirred for a further hour at room temperature, 22.19 g of a yellow-brown, very
viscous substance were obtained. Small amounts of this material were diluted with
dichloromethane, and this solution was analysed by 19F NMR spectroscopy. The
spectra were recorded using an FEP sample tube inside a 5 mm NMR tube with an
acetone-D6 film as external lock and CCl3F as internal reference.
The 19F NMR spectrum shows that in this case one mole of the acid H+[(C2F5)3PF3]-
are formed per mole of triglyme.
19F NMR spectrum of the meridional form (approx. 90%): -44.41 dm (PF); -80.35 m
(CF3); -82.00 m (2CF3); -87.94 dm (PF2); -115.87 dm (3CF2); J1P. F= 890 Hz;
J1P.F= 891 Hz; J2P.F= 90 Hz.
19F NMR spectrum of the facial form (approx. 10%): -68.29 dm; J1P. F= 794 Hz
(PF3 group).
Some signals of the facial form overlap with those of the meridional form.
Example 18
6.78 g (16.9 mmol) of polyethylene glycol 400 (PEG 400) were introduced into an
FEP flask and cooled using an ice bath. While stirring using the magnetic stirrer,
firstly 0.79 g (39.5 mmol) of hydrogen fluoride (HF) was slowly added to the PEG 400
and then a further 15.27 g (35.8 mmol) of difluorotris(pentafluoroethyl)phosphorane
were added over the course of three minutes. After this reaction mixture had been
stirred at room temperature for 10 hours, 21.8 g of a yellow-brown, dense, gelatinous
material were obtained. Small amounts of this material were diluted with dichloro-

methane, and the solution was analysed by 19F NMR spectroscopy. The spectra
were recorded using an FEP sample tube inside a 5 mm NMR tube with an acetone-
D6 film as external lock and CCl3F as internal reference.
The 19F NMR spectrum shows that in this case the acid H+ [(C2F5)3PF3]-was formed
in a polymeric matrix, approximately 2 mol of acid per mole of polyethylene glycol
400.
19F NMR spectrum of the meridional form (approx. 80%): -44.64 dm (PF); -80.48 m
(CF3); -82.07 m (2CF3); -88.00 dm (PF2); -115.94 dm (3CF2); J1P.F= 889 Hz;
J1P.F= 894 Hz; J2P.F= 95 Hz.
19F NMR spectrum of the facial form (approx. 20%): -68.16 dm; J1P.F= 788 Hz
(PF3 group).
Other signals of the facial form overlapped with those of the meridional form.
Example 19
The starting material, difluorotris(pentafluorophenyl)phosphorane, was prepared as
follows: 0.711 g (1.34 mmol) of tris(pentafluorophenyl)phosphine in 5 cm3 of dry toluene
was mixed with 0.300 g (1.77 mmol) of xenon difluoride. The gas was liberated
by heating the reaction mixture to from 50 to 60°C. The reaction was complete within
20 minutes. After the solvent had been evaporated under reduced pressure, 0.750 g
of a white, solid substance was isolated. The yield of the difluorotris(pentafluoro-
phenyl)phosphorane was 98.5 mol%. The 19F NMR spectrum of the compound
agrees with the spectra known from the literature (M. Fild and R. Schmutzler, J.
Chem. Soc. (A), 1969, pp. 840-843).
0.50 g of dried diethyl ether and 0.107 g (0.187 mmol) of difluorotris(pentafluoro-
phenyl)phosphorane in an FEP flask were cooled by means of an ice bath. Firstly
0.050 g (2.5 mmol) of hydrogen fluoride, HF, and then, overthe course of two
minutes, 0.3 g of triethylamine were added while the reaction mixture was stirred
using the magnetic stirrer. During the addition, all the phosphorane dissolved, and
triethylammonium hydrofluoride precipitated. After the sediment had been separated

off and the solvent had been evaporated under reduced pressure, 0.13 g of a viscous
substance was isolated. Small amounts of this material were dissolved in acetone-D6,
and this solution was analysed by 19F and 1H NMR spectroscopy. The spectrum confirmed
the formation of trifluorotris(pentafluorophenyl)phosphoric acid, [(C6F5)3PF3]-
H+, as a complex with triethylamine.
19F NMR spectrum (solvent: acetone-D6; reference: CCl3F, internal), d, ppm: -6.73
dm (PF); -39.71 dm (PF2); -132.06 m (4F); -134.75 m (2F); -160.421 (1F); -161.24 t
(2F); -166.20 m (6F); J1P. F= 811 Hz; J1P. F= 797 Hz; J3F. F= 20 Hz.
1H NMR spectrum (solvent: acetone-D6; reference: TMS, internal), d, ppm: 1.271
(3CH3), 3.04 q (3CH2), 12.11 s (NH+); J3H.H= 7.3 Hz.
Example 20
6.36 g (70.6 mmol) of dry dimethyl carbonate, (CH3O)2CO, in an FEP flask were
cooled using an ice bath. Firstly 10.99 g (25.8 mmol) of difluorotris(pentafluoro-
ethyl)phosphorane were slowly added to the dimethyl carbonate and then 0.615 g
(30.7 mmol) of hydrogen fluoride (HF) was added to the reaction mixture over the
course of 5 minutes while stirring using a magnetic stirrer. After the phosphorane had
dissolved and the reaction mixture had been warmed to room temperature, 17.8 g of
a colourless, clear solution were obtained.
The solution was analysed by 19F NMR spectroscopy. The spectra were recorded
using an FEP sample tube inside a 5 mm NMR tube with an acetone-D6 film as
external lock and CCl3F as internal reference.
The 19F NMR spectrum shows that in this case the meridional structure of the acid
[(C2F5)3PF3]-H+ is formed.
19F NMR spectrum: -44.34 dm (PF); -80.26 m (CF3); -81.93 m (2CF3); -87.78 dm
(PF2); -115.85 dm (3CF2); J1P.F= 889 Hz; J1P.F= 92 Hz.
1H NMR spectrum (acetone-D3film, standard: TMS): 4.49 s (CH3); 17.54 s (H+).

Applications of trifluorotris(perfluoroalkyl)phosphoric acids
Example 21
12.15 g of an 83.2% by weight, aqueous trifluorotris(pentafluoroethyl)phosphoric acid
(prepared as described in Example 1) were neutralised at 0°C with stirring by addition
of 0.95 g lithium hydroxide monohydrate in small portions. 13.1 g of a clear solution
of lithium trifluorotris(pentafluoroethyl) phosphate having a concentration of
78.2% by weight in water were obtained. The yield of the lithium trifluorotris(penta-
fluoroethyl) phosphate was virtually quantitative. The solution was analysed by 19F
NMR spectroscopy. The spectra were recorded using an FEP sample tube inside a
5 mm NMR tube with an acetone-D6 film as external lock and CCl3F in the film as
reference.
19F NMR spectrum, d, ppm: -43.48 dm (PF); -79.54 m (CF3); -81.30 m (2CF3); -88.07
dm (PF2); -114.21 dm (3CF2); J1P.F= 891 Hz; J1P. F= 908 Hz; J2P.F= 92 Hz.
Example 22
20.44 g of an 83.2% by weight, aqueous trifluorotris(pentafluoroethyl)phosphoric acid
(prepared as described in Example 1) were neutralised by addition of 1.42 g of lithium
carbonate in small portions with stirring. The yield was 21.0 g of a clear solution
of lithium trifluorotris(pentafluoroethyl) phosphate in a concentration of 82.0% by
weight in water. The yield of the lithium trifluotris(pentafluroethyl) phosphate was virtually
quantitative. The solution was analysed by 19F NMR spectroscopy. The spectra
were recorded using an FEP sample tube inside a 5 mm NMR tube with an acetone-
D6 film as external lock and CCI 3F in the film as reference.
19F NMR spectrum, d, ppm: -43.31 dm (PF); -79.44 m (CF3); -81.19 m (2CF3); -87.96
dm (PF2); -114.20 dm (3CF2); J1P. F= 891 Hz; J1P. F= 907 Hz; J2P. F= 92 Hz.
Example 23
A solution of 6.38 g (14.3 mmol) of trifluorotris(pentafluoroethyl)phosphoric acid in
1.9 q of diethyl ether (prepared analogously to the process in Example 7) was neu-

tralised by siow addition of 6.0 cm3 (15.0 mmol) of a 2.5 M solution of butyllithium in
hexane at 0°C with stirring. The mixture was stirred for a further half an hour, and the
complex of lithium trifluorotris(pentafluoroethyl) phosphate with diethyl ether (bottom,
pale-yellow, viscous layer) was separated off from the hexane (upper layer).
The 19F NMR spectrum of the diethyl ether solution showed the presence of lithium
trifluorotris(pentafluoroethyl) phosphate, which was obtained in virtually quantitative
yield. The spectra were recorded using an FEP sample tube inside a 5 mm NMR
tube with an acetone-D6 film as external lock and CCl3F in the film as reference.
19F NMR spectrum of the meridional form (approx. 85 mol%): -47.19 dm (PF);
-79.80 m (CF3); -81.34 m (2CF3); -88.77 dm (PF2); -114.84 dm (3CF2); J1P. F= 867 Hz;
J1P.F=905HZ;J2P.F=92 HZ.
19F NMR spectrum of the facial form (approx. 15 mol%): -66.88 dm; J1P. F= 776 Hz
(PF3 group).
Other signals of the facial form overlapped with those of the meridional form.
Example 24
10.77 g of an 83.2% by weight, aqueous trifluorotris(pentafluoroethyl)phosphoric acid
(prepared as described in Example 1) were diluted with 10 cm3 of water and neutralised
with 1.52 g of magnesium hydroxycarbonate (Merck, proportion of the Mg cation
at least 24%) in small portions with cooling in an ice bath and with stirring. The
excess magnesium hydroxycarbonate was filtered off, and the solution of the magnesium
trifluorotris(pentafluoroethyl) phosphate in water was analysed by 19F NMR
spectroscopy. The spectra were recorded using an FEP sample tube inside a 5 mm
NMR tube with an acetone -D6 film as external lock and CCI 3F in the film as reference.
19F NMR spectrum, d, ppm: -43.34 dm (PF); -79.35 m (CF3); -80.99 m (2CF3), -88.11
dm (PF2); -114.54 dm (3CF2); J1P. F= 874 Hz; J1P. F= 899 Hz; J2P.F= 91 Hz.

Example 25
7.19 g of an 83.2% by weight, aqueous trifluorotris(pentafluoroethyl)phosphoric acid
(prepared as described in Example 1) were diluted with 10 cm3 of water with cooling
in an ice bath and with stirring and neutralised by addition of 1.76 g of zinc hydroxy-
carbonate (Fluka, proportion of Zn cation > 58%) in small portions. The excess zinc
hydroxycarbonate was filtered off, and the solution of zinc trifluorotris(pentafiuoro-
ethyl) phosphate in water was analysed by 19F NMR spectroscopy. The spectra were
recorded using an FEP sample tube inside a 5 mm NMR tube with an acetone-D6 film
as external lock and CCl3F in the film as reference.
19F NMR spectrum, d, ppm: -43.40 dm (PF); -79.56 m (CF3); -81.23 m (2CF3); -87.91
dm (PF2); -114.45 dm (3CF2); J1P.F= 890 Hz; J1P.F= 913 Hz; J2P.F= 96 Hz.
Example 26
10.78 g of an 83.2% by weight, aqueous trifluorotris(pentafiuoroethyl)phosphoric acid
(prepared as described in Example 1) were diluted with 10 cm3 of water in an ice
bath with stirring and neutralised with 2.78 g of copper(ll) hydroxycarbonate in small
portions. The excess copper hydroxycarbonate was filtered off, and the solution of
copper trifluorotris(pentafluoroethyl) phosphate in water was analysed by 19F NMR
spectroscopy. The spectra were recorded using an FEP sample tube inside a 5 mm
NMR tube with an acetone-D6 film as external lock and CCl3F in the film as reference.
19F NMR spectrum of the meridional form, d, ppm: -47.88 dm (PF); -84.03 m (CF3);
-85.59 m (2CF3); -92.70 dm (PF2); -119.27 dm (3CF2); J1P. F= 895 Hz; J2P.F= 87 Hz.
The small signal of the facial form of the copper salt was also present in the spectrum: -
71.44 d (PF3); J1P,F= 790 Hz.

Example 27
3.10 g of a 73.0% by weight, aqueous trifluorotris(pentafluoroethyl)phosphoric acid
(prepared as described in Example 3) were diluted with 5 cm3 of water with cooling in
a water bath and with stirring and neutralised with 0.74 g of silver carbonate in small
portions. The excess silver carbonate was filtered off, and the solution of silver
trifluorotris(pentafluoroethyl) phosphate in water was analysed by 19F NMR spectro-
scopy. The spectra were recorded using an FEP sample tube inside a 5 mm NMR
tube with an acetone-D6 film as external lock and CCl3F in the film as reference.
19F NMR spectrum, 5, ppm: -42.60 dm (PF); -78.66 m (CF3); -80.35 m (2CF3); -87.41
dm (PF2); -114.06 dm (3CF2); J1P. F= 890 Hz; J2P. F= 92 Hz.
Example 28
A solution of 16.68 g (37.4 mmol) of trifluorotris(pentafluoroethyl)phosphoric acid in
14.52 g of diethyl ether (prepared as described in Example 7) was slowly added at
room temperature with stirring to 20.50 g of a 50% by weight solution of tetra-
(n-butyl)phosphonium chloride (10.25 g or 34.8 mmol) in toluene. The mixture was
stirred for a further 30 minutes, and the solvent mixture was distilled off at a reduced
pressure of 13.3 Pa. 24.46 g of a white, solid substance were obtained in this way.
The yield of tetra(n-butyl)phosphonium trifluorotris(pentafluoroethyl) phosphate was
virtually quantitative. The melting point after crystallisation from a methanol/water
mixture was 73 -74°C.
Analysis: C 37.31%, H 5.06%; calculated: 37.51%, H 5.15%.
19F NMR spectrum (solvent: acetone-D6; reference: CCl3F internal): -43.83 dm (PF);
-79.72 m (CF3); -81.23 m (2CF3); -86.77 dm (PF2); -115.43 dm (3CF2); J1P.F = 890
Hz; J1P.F = 905 Hz; J2P.F = 92 Hz.
1H NMR spectrum (solvent: acetone-D6; reference: TMS internal): 0.95 t (4CH3), 1.57
m (8CH2), 2.34 m (4CH2).

Example 29
11.37 g of a 20% by weight, aqueous solution of tetraethylammonium hydroxide were
slowly added (over the course of 2 minutes) with stirring and cooling in an ice bath to
8.28 g of an 83.2% by weight aqueous trifluorotris(pentafluoroethyl)phosphoric acid
(prepared as described in Example 1). The reaction mixture was diluted with 100 cm3
of water and stirred at room temperature for a further 10 minutes. A white sediment
was filtered off and washed twice with 30 cm3 of water. After drying overnight in air,
8.55 of a white, solid material were obtained. The yield of tetraethylammonium
trifluorotris(pentafluoroethyl) phosphate was 96.3%. Analysis: C 29.14%, H 3.40%, N
2.49%; calculated: C 29.23%, H 3.50%, N 2.43%. The melting point after crystallisation
of this product from a methanol/water mixture was unchanged at 95°C.
19F NMR spectrum (solvent: acetone-D6; reference: CCl3F internal): -43.78 dm (PF);
-79.69 m (CF3); -81.24 m (2CF3); -86.80 dm (PF2); -115.36 dm (3CF2); J1P.F = 889
Hz; J1P,F = 906 Hz; J2P.F = 89 HZ.
1H NMR spectrum (solvent: acetone-D6; reference: TMS internal): 1.39 tm (4CH3),
3.48 q (4CH2); J3H.H = 7.3 Hz.
Example 30
10.85 g of a 73.0% by weight, aqueous trifluorotris(pentafluoroethyl)phosphoric acid
(prepared as described in Example 3) were added slowly over the course of 3 minutes
with stirring and cooling in an ice-water bath to 81.47 g of aqueous tetramethyl-
ammonium hydroxide (prepared from 6.47 g of a 25% by weight aqueous
(CH3)4N+- OH by dilution with 75 cm3 of water). The reaction mixture was stirred at
room temperature for a further 10 minutes. A white sediment was filtered off and
washed three times with 30 cm3 of water. After drying overnight in air, 8.55 g of a
white, solid material were obtained. The yield of tetramethylammonium trifiuorotris-
(pentafluoroethyl) phosphate was 95.2%. The melting point was 112°C.

19F NMR spectrum (solvent: acetone-D6; reference: CCl3F internal): -43.70 dm (PF);
-79.70 m (CF3); -81.24 m (2CF3); -86.75 dm (PF2); -115.43 dm (3CF2); J1P.F = 889
Hz; J1P.F = 909 Hz; J2P.F = 88 Hz.
1H NMR spectrum (solvent: acetone-D6; reference: TMS internal): 3.42 s (4CH3).
Example 31
3.95 g of an 85.9% by weight aqueous tetrafluorobis(nonafluoro-n-butyl)phosphoric
acid (prepared as described in Example 15) were slowly added over the course of 3
minutes to 54.58 g of aqueous tetraethylammonium hydroxide (prepared from 4.58 g
of a 20% by weight, aqueous (C2H5)4N+-OH solution by dilution with 50 cm3 of water)
with stirring and with cooling of the reaction mixture in an ice bath. The reaction mixture
was stirred at room temperature for a further 10 minutes. A white sediment was
filtered off and washed twice with 10 cm3 of water. After drying overnight in air, 3.05 g
of a white, solid material were obtained. The yield of tetraethylammonium tetra-
fluorobis(nonafluoro-n-butyl) phosphate was 72.6%.
19F NMR spectrum (solvent acetone-D6; reference: CCl3F internal): -70.20 dm (PF4);
-80.87 m (2CF3); -116.04 dm (2CF2); -122.34 m (2CF2); -124.61 t (2CF2); J1P.F =
930 Hz; J2P.F = 94 Hz; J4P.F = 15.7 Hz.
1H NMR spectrum (solvent: acetone-Del reference: TMS internal): 1.38 tm (4CH3),
3.48 q (4CH2); J3H.H = 7.3 Hz.
Example 32
0.030 g of lithium powder was added in small portions at room temperature and with
stirring using a magnetic stirrer to 1.72 g of a solution of trifluorotris(pentafluoroethyl)-
phosphoric acid in dimethyl carbonate, prepared as described in Example 20. At the
beginning, the reaction mixture reacted vigorously with evolution of hydrogen. Complete
reaction of the reaction components was achieved by warming the reaction
mixture to 60°C over a period of 30 minutes.

After the excess lithium powder had been separated off, the solution of lithium
trifluorotris(pentafluoroethyl) phosphate in dimethyl carbonate was analysed by 19F
NMR and 1H NMR spectroscopy. The spectra were recorded using an FEP sample
tube inside a 5 mm NMR tube with an acetone-D6 film as external lock and CCl3F in
the film as reference.
19F NMR spectrum of the meridional form (~ 85 mol%): -44.53 dm (PF); -79.90 m
(CF3); -81.71 m (2CF3); -87.77 dm (PF2); -115.23 dm (3CF2); J1P.F= 888 Hz; J2P.F=
91 Hz.
19F NMR spectrum of the facial form (* 15 mol%): -67.98 dm; J1P.F= 785 Hz (PF3
group). Other signals of the facial form overlapped with those of the meridional form.
1H NMR spectrum (acetone-D3 film, reference; TMS): 4.35 s (CH3).
Example 33
16.09 g of trifluorotris(pentafluoroethyl)phosphoric acid in dimethyl carbonate, prepared
as described in Example 20, were diluted with 6.78 g of dry dimethyl carbonate
and reacted with 0.25 g of lithium hydride, which was added to the reaction mixture in
small portions with stirring using a magnetic stirrer and with cooling in an ice bath. At
the beginning, this reaction mixture reacted vigorously with evolution of hydrogen.
When all the lithium hydride had been added, the mixture was warmed to room temperature
and stirred for a further hour.
After the excess lithium hydride had been separated off, the solution of lithium
trifluorotris(pentafluoroethyl) phosphate in dimethyl carbonate was analysed by 19F
NMR and 1H NMR spectroscopy. The spectra were recorded using an FEP sample
tube inside a 5 mm NMR tube with an acetone-D6 film as external lock and CCl3F as
internal reference.

19F NMR spectrum of the meridional form (˜ 85 mol%): -44.07 dm (PF); -80.12 m
(CF3); -81.77 m (2CF3), -87.52 dm (PF2); -115.17 dm (3CF2): J1P.F= 888 Hz; J2P.F=
87 Hz.
19F NMR spectrum of the facial form (˜15 mol%): -68.40 dm; J1P.F= 795 Hz (PF3
group). Other signals of the facial form overlapped with those of the meridional form.
1H NMR spectrum (acetone-D3 film, standard: TMS): 4.21 s (CH3).
This solution can be employed directly for the preparation of electrolytes for lithium
batteries.

WE CLAIM;
1. An acid of the formula [I]
[RyPF6-y]-H+
[I]
where
Y=1,2 or 3,
and wherein
the ligands R may be identical or different, and
R is a perfluorinated C1-8 -alkyl or aryl group or R is a partially
fluorinated C1-8-alkyl or aryl group wherein optionally some of
the F or H are substituted by chlorine.
2. Acid as claimed in Claim 1, wherein at least one R is a
nonafluoro butyl or pentafluorophenyl group, particularly
preferably a pentafluoroethyl group.
3. Acid as claimed in Claim 1 or 2, wherein y=2 or 3, preferably
y=3.

4. Acid as claimed in one of Claim 1 to 3:
trifluorotris (pentafluoroethyl)phosphoric acid,
trifluorotris (heptafluoro-n-propyl)phosphoric acid,
trifluorotris (nonafluoro-n-butyl)phosphoric acid,
tetrafluorobis (nonafluoro-n-butyl)phosphoric acid,
pentafluoro (nonafluoro-n-butyl)phosphoric acid,
tetrafluorobis (heptafluoro-i-propyl)phosphoric acid.
5. Process for the preparation of an acid as claimed in one of
Claims 1 to 4, a perfluoroalkylphosphorane is reacted with
hydrogen fluoride in the presence of a suitable solvent and/or
proton acceptor.
6. Process as claimed in Claim 5, wherein the solvent and/or
proton acceptor employed is water, alcohols, ethers, sulfides,
amines, phosphines, carboxylic acids, esters, glycols,
polyglycols, polyamines, polysulfides or mixtures of at least two
of these solvents and/or proton acceptors.
7. Process as claimed in Claim 6, wherein the suitable solvent
and/or proton acceptor is methanol, ethanol, acetic acid,
dimethyl ether, diethyl ether, dimethyl carbonate, dimethyl

sulfide, dimethylformamide, triethylamine, triphenylphosphine,
or a mixture of at least two of these compounds.
8. Process as claimed in one of Claims 5 to 7, the reaction of the
perfluoroalkylphosphorane with a solution of hydrogen fluoride
is carried out in a solvent in a concentration of greater than
0.1% by weight of HF, preferably greater than 5% by weight of
HF, particularly preferably greater than 10% by weight and very
particularly preferably greater than 20% by weight, but less
than 100% by weight, of HF.
9. Process as claimed in one of Claims 5 to 8, wherein the reaction
of the perfluoroalkylphosphorane is carried out at a
temperature of from -50 to +100°C, preferably at a temperature
of from -35 to +50°C, particularly preferably at from 0 to 25°C.
10. Solution of an acid as claimed in Claims 1 to 4 and a solvent,
wherein the acid is present in a concentration of greater than
2% by weight, preferably greater than 20% by weight,
particularly preferably greater than 70% by weight and very
particularly preferably greater than 80% by weight.

11. Process for the preparation of a salt of the general formula [II]
[RyPF6-y]m-Mm+ [II]
where
Mm+ is a mono-, di- or trivalent cation,
m=1, 2 or 3
and y=1,2 or 3,
and in which
the ligands R may be identical or different, and
R stands for a perfluorinated C1-8-alkyl or aryl group or R
stands for a partially fluorinated C1-8-alkyl or aryl group in
which some of the F or H may be substituted by chlorine, where
the perfluorinated and partially fluorinated alkyl or aryl groups R
may be in the form of chain or ring structures,
wherein an acid as claimed in one of claims 1 to 4 is reacted in a
suitable solvent with a salt of the general formula [III]

where
Mm+ is a mono-, di- or trivalent cation,

A stands for a basic or neutral anion or a mixture of basic anions
or a mixture of at least one basic and at least one neutral anion,
and m=l,2 or 3,
or with metals, metal hydrides, metal oxides or metal hydroxides.
12. Process as claimed in Claim 11, wherein the salt of the general
formula [III] contains at least one oxide, hydride, carbonate,
hydroxide, chloride, fluoride, formate, acetate and/or or
trifluoroacetate anion.
13. Process as claimed in Claim 11, wherein the metals employed
for the neutralization are Li, Na, K, Rb, Mg, Cs, Ca, Sr, Ba, Sc,
Y, Yb, La, Al, In, Cd and/or Zn.
14. Process as claimed in Claim 11, wherein the oxides employed
for the neutralization are Li2O, Na2O, K2O, MgO, CaO, SrO,
BaO, Sc2O3, Y2O3, Yb2O3, La2O3, Al2O3, CdO, ZnO, CuO, FeO
and/or Fe2O3.
15. Process as claimed in Claim 11, wherein the hydroxides
employed for the neutralization are LiOH, NaOH, KOH, RbOH,



CsOH, Mg(OH)2, Ca(OH)2, Sr (OH)2, Ba(OH)2, Cd(OH)2, Zn(OH)2,
Sc(OH)3, Al (OH)3 and/or Cu(OH)2.
16. Process as claimed in Claim 11, wherein the hydrides employed
for the neutralization are LiH, NaH, CaH2, YH3 and/or A1H3.
The present invention relates to acids of the general
formula (1), RyPF6-y H+(1), where y =1,2 or 3,
and in which the ligands R may be identical or different and
R is a perfluorinated CH1-8 alkyl or aryl group or R is a
partially fluorinated C1-8 alkyl or aryl group, in which some
of the F or H may have been substituted by chlorine. The
present invention furthermore relates to a process for the
preparation of the acids according to the invention, to salts
comprising a cation and the anion of the acid according to the
invention, and to a process for the preparation of the salts.
The invention furthermore relates to the use of the
acids and salts according to the invention.

Documents:

58-KOLNP-2004-FORM-27.pdf

58-kolnp-2004-granted-abstract.pdf

58-kolnp-2004-granted-claims.pdf

58-kolnp-2004-granted-correspondence.pdf

58-kolnp-2004-granted-description (complete).pdf

58-kolnp-2004-granted-examination report.pdf

58-kolnp-2004-granted-form 1.pdf

58-kolnp-2004-granted-form 18.pdf

58-kolnp-2004-granted-form 2.pdf

58-kolnp-2004-granted-form 3.pdf

58-kolnp-2004-granted-form 5.pdf

58-kolnp-2004-granted-reply to examination report.pdf

58-kolnp-2004-granted-specification.pdf

58-kolnp-2004-granted-translated copy of priority document.pdf


Patent Number 225213
Indian Patent Application Number 58/KOLNP/2004
PG Journal Number 45/2008
Publication Date 07-Nov-2008
Grant Date 05-Nov-2008
Date of Filing 16-Jan-2004
Name of Patentee M/S MERCK PATENT GMBH
Applicant Address FRANKFURTER STRASSE 250, 64293 DARMSTADT
Inventors:
# Inventor's Name Inventor's Address
1 WILLNER, HELGE FOHRENKAMP 3, 45481 MUHLHEIUM/RUHR
2 IGNATYEV NIKOLAI PRINZENSTR. 104 47058 DUISBURG
3 SCHMIDT, MICHAEL WEINBERGSTRASSE 41, 64342 SEEHEIM-JUGENHEIM
4 KUHNER, ANDREAS BARKHAUSSTRASSE 22, 64289 DARMSTADT
5 HILARIUS, VOLKER RAIBACHER TAL 25, 64823 GROSS-UMSTADT
6 HEIDER, UDO LAGERSTRASSE 37A 64560 RIEDSTADT-CRUMSTADT
7 KUCHERYNA, ANDRIY WORTHSTRASSE 6, 47053 DUISBURG
8 SARTORI, PETER ZUR LUDWIGSHOHE 28, 86919 UTTING
PCT International Classification Number C07F 9/28
PCT International Application Number PCT/EP2002/06360
PCT International Filing date 2002-06-11
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 10130940.6 2001-06-27 Germany