A new route to perfluorinated vinyl ether monomers: Synthesis of perfluoro(alkoxyalkanoyl) fluorides from non-fluorinated compounds

Article abstract of DOI:10.1016/S0022-1139(01)00474-2

A new synthetic procedure for the preparation of various perfluoro(alkoxyalkanoyl) fluorides, which are precursors to perfluorinated vinyl ether monomers, from non-fluorinated alkoxyalcohols has been developed. Available perfluoro(alkoxyalkanoyl) fluoride

Full text of DOI:10.1016/S0022-1139(01)00474-2

Journal of Fluorine Chemistry 112 ꢀ2001) 109±116
A new route to per¯uorinated vinyl ether monomers: synthesis of
per¯uoroꢀalkoxyalkanoyl) ¯uorides from non-¯uorinated compounds
Takashi Okazoe*,Kunio Watanabe,Masahiro Itoh,Daisuke Shirakawa,Shin Tatematsu
Research Center, Asahi Glass Co. Ltd., 1150 Hazawa-cho, Kanagawa-ku, Yokohama 221-8755, Japan
Abstract
A new synthetic procedure for the preparation of various per¯uoroꢀalkoxyalkanoyl) ¯uorides,which are precursors to per¯uorinated
vinyl ether monomers,from non-¯uorinated alkoxyalcohols has been developed. Available per¯uoroꢀalkoxyalkanoyl) ¯uorides such as
per¯uoroꢀ2-propoxypropionyl) ¯uoride,so-called HFPO dimer,can be multiplied by the use of the hydrocarbon counterpart alcohols and
¯uorine gas as raw materials. In the case that the desired per¯uoroꢀalkoxyalkanoyl) ¯uoride is not readily available,it can be obtained from
its hydrocarbon counterpart alcohol and an available per¯uoroacyl ¯uoride. # 2001 Elsevier Science B.V. All rights reserved.
Keywords: Acyl ¯uorides; Direct ¯uorination; Fluorine; Per¯uoropolymers; Synthesis
1. Introduction
applied to the synthesis of the precursor to per¯uorinated
polymers.
Per¯uoroꢀ2-alkoxyalkanoyl) ¯uorides are important inter-
mediates for ¯uororesins,such as PFA ꢀper¯uoroalkoxy
copolymer). PFA is one of the most important per¯uorinated
polymers that is used as both thermally and chemically
resistant material with melt processibility for industrial
purpose [1±6]. One of its monomers,per¯uoroꢀpropyl vinyl
ether) ꢀPPVE),has been prepared via dimerization of hexa-
¯uoropropylene oxide ꢀHFPO) [7] ꢀScheme 1). Although the
HFPO chemistry is well established,it is speci®c to the
propoxyl group as the side chain in the polymer in this case,
because HFPO itself is employed as the precursor of the
per¯uoroalkoxide to react with HFPO. In the case of the
per¯uoroꢀalkyl vinyl ethers) other than PPVE,the prepara-
tion of the precursor per¯uoroꢀ2-alkoxyalkanoyl) ¯uoride is
costly [8±10].
Herein we present an essentially different synthesis. Our
new synthetic route starts from non-¯uorinated counterparts
and utilizes liquid-phase direct ¯uorination [14] as a key
step. Although Lagow and co-workers reported liquid-phase
direct ¯uorination of non-¯uorinated compounds [14],they
just adopted it to molecules with simple structure,such as
octyl octanoate. We considered that it could be applied to the
synthesis of industrially important compounds,such as
per¯uorinated alkyl vinyl ethers,if we could make the
corresponding hydrocarbon counterparts.
2. Results and discussion
2.1. Synthesis of the precursors to PPVE
Recent per¯uorinated hypo¯uorite chemistry [11] and the
¯uorination method of partially-¯uorinated 1,2-dichlor-
oethyl ethers [12] can give per¯uoroꢀalkyl vinyl ethers)
other than PPVE. However,these methods are still costly,
because they require expensive ꢀper)¯uorinated starting
materials.
On the other hand,a process for converting per¯uorinated
esters to per¯uorinated acyl ¯uorides with a nucleophile in a
solvent has been reported [13]. However,it has not been
We chose PPVE as our ®rst target molecule,because it has
a relatively simple structure. PPVE can be made either by
thermal elimination of per¯uoroꢀ2-propoxypropionyl) ¯uor-
ide ꢀ1) or by dechlorination of per¯uoroꢀ1,2-dichloroethyl
propyl ether) ꢀ2). The dichloroether ꢀ2) could be obtained by
direct ¯uorination of the corresponding hydrocarbon 1,2-
dichloroethyl propyl ether ꢀ3),which is obtained from
inexpensive propyl vinyl ether in only one step [15,16].
Because it seemed relatively easy,this route was selected as
our ®rst trial [17].
* Corresponding author. Tel.: ‡81-45-374-8737; fax: ‡81-45-374-8834.
E-mail address: okazoe@agc.co.jp ꢀT. Okazoe).
The dichloroethyl ether ꢀ3) was unstable,and it was
dif®cult to purify by distillation or even by chromatography.
0022-1139/01/$ ± see front matter # 2001 Elsevier Science B.V. All rights reserved.
PII: S 0 0 2 2 - 1 1 3 9 ꢀ 0 1 ) 0 0 4 7 4 - 2

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T. Okazoe et al. / Journal of Fluorine Chemistry 112 12001) 109±116
Scheme 1. Conventional synthesis of PPVE.
Scheme 2.
Scheme 3.
Therefore,the direct ¯uorination without puri®cation of the
substrate was carried out,basically applying Lagow's
method. The direct ¯uorination was conducted with 20%
¯uorine gas diluted in nitrogen gas,and proceeded as we had
intended ꢀScheme 2). However,it was limited by migration
of chlorine atoms and formation of considerable amounts of
by-products arising from C±C and C±O bond cleavage. The
cause of this was probably some reaction in the vapor-phase,
due to high volatility of the substrate,and the yield was only
40% at best. This suggested that compounds with low
volatility are desirable for the liquid-phase reaction.
Then we examined the synthesis of the per¯uoroacyl
¯uoride 1 [17]. This compound could be derived from
alkoxyalcohol 4 as the precursor,however,direct ¯uorina-
tion of it seemed to be dangerous,because formation of
unstable hypo¯uorite would likely to occur ®rst [18]. As a
result,protection of the OH group was essential in this
route. The protecting group,in this case,should be a
per¯uorinated group for inactivity against ¯uorination,of
large molecular weight for low volatility and removable
after ¯uorination. Considering these demands,±COCFꢀC-
F3)OCF2CF2CF3 seemed to be most attractive,because the
corresponding acyl ¯uoride is available as the intermediate
to PPVE in the conventional manufacturing process,and,it
could give the same acyl ¯uoride from per¯uorinated
hydrocarbon moiety,after addition of ¯uoride ion followed
by elimination.
The actual synthesis was carried out as follows. The
starting non-¯uorinated alcohol 4 was synthesized from
inexpensive propylene oxide and 1-propanol in the presence
of an acid catalyst in one step [19±21]. Esteri®cation
ꢀScheme 3) was carried out simply by mixing the non-
¯uorinated alcohol 4 and the per¯uoroacyl ¯uoride 1 from
the conventional manufacturing route,with removal of HF
formed during the reaction in a stream of nitrogen,to give
the partially-¯uorinated ester 5 in 99% yield.
The next liquid-phase direct ¯uorination was carried out
basically in manner similar to Prof. Lagow's method
ꢀScheme 4). Cooling was required in order to control the
reaction together with use of an inert solvent,and appro-
priate dilution of both ¯uorine and the substrate. However,
an excess of ¯uorine to replace all of the hydrogen atoms in
the substrate was essential at all times as in the case of the
non-¯uorinated substrates that are described in the literature
[14,22]. In our method, however, a potentially dangerous
vapor-phase reaction was avoided by employing a higher
Scheme 4.

T. Okazoe et al. / Journal of Fluorine Chemistry 112 12001) 109±116
111
2.2. Synthesis of perfluoro1alkoxyalkanoyl) fluorides
via perfluorinated mixed esters
In cases where the desired per¯uoroacyl ¯uoride is avail-
able,it can be multiplied by the method shown above,but in
many cases,the desired acyl ¯uorides are not readily avail-
able. In such situations,the hydrocarbon counterpart alcohol
4a with the structure corresponding to the desired acyl
¯uoride 1a is reacted with an available acyl ¯uoride 1b
ꢀScheme 7). The resulting mixed ester 5ab is ¯uorinated to
give the per¯uoroester 6ab,and the following thermal
elimination gives the desired acyl ¯uoride 1a and the
recovered starting one 1b. Once the desired acyl ¯uoride
1a is obtained,then it can be multiplied by synthesizing the
homoester 5aa and applying the PERFECT process. Thus,
liquid-phase direct ¯uorination followed by thermal elim-
ination gives 2 mol of the desired acyl ¯uoride 1a.
According to this methodology,various per¯uoroacyl
¯uorides were synthesized.
When the hydrocarbon counterpart alkoxyalcohol 10 is
not commercially available,it was synthesized from inex-
pensive 2-chloropropionyl chloride in three steps as shown
in Scheme 8. The reaction of the alcohol 7,which is
corresponding to alkoxy moiety,with 2-chloropropionyl
chloride gave propionate ester 8. Nucleophilic substitution
with alkoxide [25,26] of the alcohol 7 gave 2-alkoxypro-
pionate 9. Reduction with sodium bisꢀ2-methoxyethoxy)-
aluminum hydride in toluene gave the desired alkoxyalcohol
10. Esteri®cation with the available acyl ¯uoride 1,the
precursor of PPVE in the conventional manufacturing pro-
cess,gave the substrate partially-¯uorinated ester 11 for the
liquid-phase direct ¯uorination.
Scheme 5.
molecular weight partially-¯uorinated ester as the substrate.
A further bene®t is that the solubility of the substrate in the
per¯uorinated solvent increased [23]. This is in contrast to
that of a non-¯uorinated compound. Moreover,it was found
that the starting acyl ¯uoride itself is a good solvent for this
¯uorination. Thus,the direct ¯uorination of the partially-
¯uorinated ester 5 was carried out with 1.5±3.0 equivalent of
¯uorine diluted to 20±50% in nitrogen to give the desired
per¯uoroester 6 in over 90% yield. In the case that conver-
sion was not enough,addition of benzene was effective in
order to initiate the formation of ¯uorine atoms to complete
the ¯uorination process.
The per¯uorinated ester 6 obtained was converted to the
desired acyl ¯uoride 1 with 30 mol% of sodium ¯uoride as
a catalyst ꢀScheme 5). This thermal elimination reaction
gave 2 mol of the desired acyl ¯uoride in 99% yield at
lower temperature,compared to the reaction without cat-
alyst [24].
The total process to a per¯uorinated vinyl ether is shown
in Scheme 6. We named this process ``PERFECT'',that is,
the abbreviation of per¯uorination of an esteri®ed com-
pound then thermal elimination. For the case of the synthesis
of PPVE,the overall yield of the acyl ¯uoride 1a from the
one we started with was 180% per cycle. By repeating the
cycle,the acyl ¯uoride 1a will increase in geometric pro-
gression. In this sense,the cycle is a multiplication of the
acyl ¯uoride.
When the substrate for the direct ¯uorination has a
dioxolane unit,the desired counterpart-alcohol 13 was
synthesized as shown in Scheme 9. Esteri®cation with the
available acyl ¯uoride 1 gave the substrate partially-¯uori-
nated ester 14 for the liquid-phase direct ¯uorination.
Scheme 6. The ``PERFECT'' cycle.

112
T. Okazoe et al. / Journal of Fluorine Chemistry 112 12001) 109±116
Scheme 7.
The partially-¯uorinated esters were per¯uorinated by the
408C at 0±0.2 MPa. The results are summarized in Table 1.
Both acyclic and cyclic partially-¯uorinated esters were
per¯uorinated in good yields ꢀruns 1 and 2). The yield of
the compound with longer alkyl chain was a little lower,
because some C±C bond cleavage took place ꢀrun 1).
Dioxolane derivatives were also ¯uorinated in good yields
ꢀruns 3 and 4). Compounds with an aromatic moiety were
also ¯uorinated,but the yields were quite low ꢀruns 5 and 6).
For example,although direct ¯uorination of the substrate
liquid-phase direct ¯uorination. A 5.0 g of the substrate ꢀ5%
solution in 1,1,2-trichlorotri¯uoroethane ꢀR113)) was con-
tinuously introduced to R113 ꢀ200 ml) at 258C with blowing
20% F2/N2 at a ¯ow rate controlled at a ratio of F2=H ˆ 3:0±
4.5 ꢀ3.0±4.5 equivalent excess to replace all of the hydrogen
atoms in the substrate). Then 0.01% benzene ꢀ0.010±0.036
equivalent) in R113 was intermittently introduced as con-
tinued blowing 20% F2/N2 with raising temperature up to
Scheme 8.
Scheme 9.

T. Okazoe et al. / Journal of Fluorine Chemistry 112 12001) 109±116
113
Table 1
Liquid-phase direct fluorination of partially-fluorinated estersa
Run
1
Substrate
Product
Yield
69
2
3
75
87
4
5
78
21
6
7
25
86
a Rf: ±CFꢀCF3)OCF2CF2CF3.
with a phenyl moiety ꢀrun 5) gave the same product as the
one from the cyclohexyl derivative ꢀrun 2),the yield was
only 21%. Formation of a lot of C±C bond dissociation
products was observed. This was probably due to too much
radicals generated from the reaction of F2 and the phenyl
moiety. On the other hand,¯uorination with a simple vinyl
moiety gave the desired product in good yield ꢀrun 7).
In order to obtain an intermediate for the transparent
¯uororesin,the compound with vicinal dichloro moiety
was per¯uorinated ꢀTable 2). When the ¯uorination was
carried out as usual at temperature of 25±408C,chlorine
migration [27,28] took place partially ꢀrun 1). It was found
that this chlorine migration depended on reaction tempera-
ture. When most of the ¯uorination was carried out at À108C
and the last part of ¯uorination for remaining hydrogen
atoms was carried out at 408C,the migration was suppressed
ꢀrun 2). This suggested that the chlorine migration did not
take place even at 408C after most of the hydrogen atoms
were substituted by ¯uorine atoms.
Thermal elimination of the obtained per¯uoroesters with
a catalytic amount of sodium ¯uoride gave the desired acyl
¯uorides with the recovery of the starting acyl ¯uoride 1.
The results are shown in Table 3.
The per¯uorinated acyl ¯uoride 1a can be converted to the
desired per¯uoroꢀalkyl vinyl) ethers as described in the
literature [29].
Thus,general organic synthesis,liquid-phase direct ¯uor-
ination,and thermal elimination in ¯uorine chemistry are

114
T. Okazoe et al. / Journal of Fluorine Chemistry 112 12001) 109±116
Table 2
Liquid-phase direct fluorination of a chlorine-containing partially-fluorinated estera
Run
Temperature ꢀ8C)
Yield ꢀ%)
1
2
25±40
63
58
32
3
À10±40
a Rf: ±CFꢀCF3)OCF2CF2CF3.
Table 3
Thermal elimination of perfluoroestersa
Substrate
Product
Amount NaF ꢀmol%)
18
Temperature ꢀ8C)
Yield ꢀ%)
66
120
20
120
73
a Rf: ±CFꢀCF3)OCF2CF2CF3.
united to afford a new methodology to synthesize various
per¯uoroꢀalkyl vinyl) ethers. Scale-up of this process is
under investigation.
Therawmaterialsareinexpensivehydrocarboncompounds
and¯uorinegas. Therefore,thismethodisexpectedtoprovide
useful per¯uorinated compounds in reasonable price.
3. Conclusions
4. Experimental
The synthetic method of various per¯uoroꢀalkoxyalka-
noyl) ¯uorides utilizing liquid-phase direct ¯uorination
with elemental ¯uorine was investigated. Direct ¯uorina-
tion of a partially-¯uorinated ester synthesized from a non-
¯uorinated alkoxyalcohol and per¯uorinated acid ¯uoride
ꢀ1) was achieved in high yield. Degradation of the result-
ing per¯uoroester gave the desired acid ¯uoride. It has
advantages over known direct ¯uorination methods as
follows.
4.1. General
NMR spectra were obtained on a JEOL EX-400 ꢀtetra-
methylsilane as internal standard for 1H,and trichloro¯uor-
omethane for 19F). High resolution mass spectra were
obtained on JEOL SX-102A coupled to HP-5890 with a
60 m capillary column J&W DB-1 or DB-1301.1 Elemental
¯uorine was generated by FluorodecTM 30,Fluoro Gas ꢀUK).
Elemental ¯uorine is highly toxic and corrosive gas,and may
cause explosion when it meets organics in the vapor-phase.
Extreme care must be taken when handling it! Both the liquid
and vapor of hydrogen ¯uoride ꢀbp 19.58C) evolved during
the reaction are also highly corrosive and cause severe burns
when in contact. Care must be taken! Prior to use,all hydro-
carbon greases must be removed and the apparatus must be
gradually passivated with elemental ¯uorine. Although the
use of 1,1,2-trichlorotri¯uoroethane ꢀR113) is regulated, we
will mention experimental examples with it for convenience,
1. It avoids vapor-phase reaction by employing a substrate
with low vapor pressure.
2. It significantly increases the solubility of the substrate in
the perfluorinated solvent used for fluorination,com-
pared to non-fluorinated ester.
3. It is easy to synthesize the partially-fluorinated substrate
because perfluorinated acyl fluoride ꢀ1) is available.
4. Various perfluoroacyl fluorides can be synthesized,
because its carbon backbone is synthesized in hydro-
carbon compounds by ordinary organic synthesis.
1 Details of the analytic method will be reported separately.

T. Okazoe et al. / Journal of Fluorine Chemistry 112 12001) 109±116
115
because it is still much more cheaply available ꢀAldrich) than
compound ꢀ1) for use as solvent. Care must be taken in order
not to emit it to the environment by using,for example,a
rotary evaporator with PTFE diaphragm type vacuum pump
and cooling trap. Once enough of the compound ꢀ1) is
obtained in the cycle,it should be used instead of R113.
Other reagents were obtained from Kanto Chemicals ꢀJapan)
and used without puri®cation.
Then,the pressure was adjusted to atmospheric pressure,and
while maintaining the internal temperature of the reactor at
408C,another portion of benzene solution ꢀ6 ml) was
injected. The same operation was repeated four times.
The total amount of benzene injected was 0.340 g
ꢀ4.35 mmol),and the total amount of R113 injected was
33 ml. Further,nitrogen gas was blown into the mixture for
1.5 h. The desired product was quantitatively analyzed by
19F NMR. The yield of 15d was 78%; 19F NMR
4.2. Typical procedure
ꢀ376.2 MHz,CDCl ) À77.9 ꢀ1F, h), À79.6 to À80.8 ꢀ1F,
3
c), À81.1 ꢀ3F, i), À81.2 ꢀ3F, j), À81.8 to À82.6 ꢀ3F of a,3F
of e and 1F of h), À85.9 to À88.0 ꢀ1F of c and 2F of f),
À122.6 ꢀ1F, g), À130.4 ꢀ2F, b), À132.4 and À132.5 ꢀ1F, d);
4.2.1. 12,2-Dimethyl-1,3-dioxolan-4-yl)methyl
perfluoro12-propoxypropionate) 111d)
‡
‡
Acyl ¯uoride 1 ꢀ40.0 g,120 mmol) was added dropwise to
solketal ꢀ2,2-dimethyl-1,3-dioxolane-4-methanol, 15.0 g,
113 mmol) over a period of 30 min while bubbling nitrogen
gastostrip off hydrogen ¯uoride evolved,andmaintainingthe
internal temperature between 25 and 308C. After the addition,
stirring was continued at room temperature for 3 h,and an
aqueous saturated sodium hydrogen carbonate solution was
added at an internal temperature of not higher than 158C. The
organic layerwas washed twicewith water ꢀ50 ml),dried over
magnesium sulfate and then subjected to ®ltration. The crude
liquid obtained was evaporated under reduced pressure to
obtain compound 11d ꢀ11.3 g,26.4 mmol,23% yield,99%
purity by GC); 1H NMR ꢀ399.8 MHz,CDCl 3) d 1.36 and 1.42
high resolution mass spectrum ꢀEI ) 622.9418 ꢀ[M À F] ,
calculated for C12F21O5: 622.9410) ꢀFig. 1).
4.2.3. 2,2-Bis1trifluoromethyl)-4,5,5-trifluoro-
1,3-dioxolane-4-carbonyl fluoride 116d)
In a 50 ml ¯ask with re¯ux condenser adjusted at 208C,a
suspension of 15d ꢀ1.8 g,2.8 mmol) and NaF powder
ꢀ0.02 g,0.5 mmol) was heated at 120 8C for 12 h with
vigorous stirring. After cooling,a liquid obtained ꢀ1.6 g)
was con®rmed to be the mixture of 1 and 16d. The NMR
spectrum of 16d obtained corresponded with the literature
[30]. The yield of 16d was determined by an internal
standard ꢀC6F6) and found to be 73%.
ꢀs,6H),3.78 and 4.10 ꢀdt, 3J ˆ 8:8 Hz, J ˆ 5:2 Hz; dd,
4
3J ˆ 8:8 Hz, 4J ˆ 6:4 Hz,2H),4.31±4.51 ꢀm,3H);
19F
4.2.4. 2-13,4-Dichlorobutoxy)propyl perfluoro-
12-propoxypropionate) 111h)
NMR ꢀ376.2 MHz,CDCl ) À80.3 ꢀ1F,OCF ), À81.8 ꢀ3F,
3
2
Cꢀ=O)CFꢀCF3)O), À82.6 ꢀ3F,OCF CF2CF3), À87.0 ꢀ1F,
2-ꢀ3-Butenyloxy)-1-propanol ꢀ19.2 g,98% purity,
145 mmol) was stirred while bubbling nitrogen gas. Calcium
chloride ꢀ2.2 g,20 mmol) and water ꢀ3.6 g) were added,
followed by cooling to 108C. Chlorine gas was blown into
for 2 h at a supply rate of about 4 g/h. Then,consumption of
the starting material was con®rmed by GC,and diethyl ether
ꢀ200 ml) and water ꢀ200 ml) were added. The organic layer
was dried over magnesium sulfate. Then,the solvent was
distilled off. The crude product was put into a ¯ask and
stirred while bubbling nitrogen gas. Acyl ¯uoride 1 ꢀ50 g,
150 mmol) was added dropwise over 1 h while maintaining
the internal temperature at 25±308C. After completion of the
dropwise addition,stirring was continued at room tempera-
ture for 3 h and saturated aqueous sodium hydrogen carbo-
nate solution ꢀ80 ml) was added at the internal temperature
of not higher than 158C. Water ꢀ50 ml) and chloroform
ꢀ100 ml) were added. The organic layer was washed with
water ꢀ100 ml) twice,dried over magnesium sulfate and
2
OCF2), À130.2 ꢀ2F,OCF CF2CF3), À132.2 ꢀ1F,Cꢀ=O)-
2
‡
CFꢀCF3)O); high resolution mass spectrum ꢀCI ) 445.0537
ꢀ[M ‡ H] ,calculated for C 12H12F11O5: 445.0509).
‡
4.2.2. Perfluoro[12,2-dimethyl-1,3-dioxolan-4-yl)methyl
2-propoxypropionate] 115d)
In a 500 ml autoclave made of nickel,equipped with a
condenser maintained at 208C,an NaF pellet packed layer,
and a condenser maintained at À108C in series at the gas
outlet of the autoclave,as well as a liquid returning line in
order to return the condensed liquid from the condenser
maintained at À108C,R113 ꢀ312 g) was stirred and main-
tained at 258C. Nitrogen gas was blown into the system for
1.0 h,and then,¯uorine gas diluted to 20% with nitrogen gas
was blown into the mixture for 1 h at a ¯ow rate of 7.71 l/h at
atmospheric pressure. While blowing the 20% ¯uorine/
nitrogen at the same rate,a solution of 11d ꢀ5.01 g,
11.7 mmol) in R113 ꢀ100 g) was injected over a period of
5.6 h. Then,while blowing the 20% ¯uorine/nitrogen at the
same rate,a solution of benzene in R113 ꢀ0.01 g/ml) was
injected in an amount of 9 ml while raising the temperature
from 25 to 408C. Then,the inlet for benzene injection was
closed,and the outlet valve of the autoclave was closed.
When the pressure reached 0.20 MPa,the ¯uorine gas inlet
valve of the autoclave was closed,and stirring was continued
for 0.9 h. During this time,the pressure dropped slightly.
Fig. 1.

116
T. Okazoe et al. / Journal of Fluorine Chemistry 112 12001) 109±116
Fig. 2.
È
[2] K. Hintzer,G. Lo hr,Melt processable tetrafluoroethylene±perfluor-
subjected to ®ltration to obtain a crude liquid. The crude
liquid was concentrated and puri®ed by a silica gel column
chromatography ꢀeluent: hexane/ethyl acetate ˆ 4=1),fol-
lowed by puri®cation again by a silica gel column chroma-
tography ꢀeluent: AK-225) to obtain 11h ꢀ37 g,72 mmol,
50%yield,99% purity by GC); 1H NMR ꢀ399.8 MHz,
opropylvinyl ether copolymers ꢀPFA),in: J. Scheirs ꢀEd.),Modern
Fluoropolymers,Wiley,Chichester,1997,pp. 223±237.
[3] T. Hiyama,Organofluorine Compounds,Springer,Berlin,2000,
pp. 212±233.
[4] R.L. Powell,Polymers,in: B. Baasner,H. Hagemann,J.C. Tatlow
ꢀEds.),Methoden. Org. Chem. ꢀHouben-Weyl),4th Edition,Georg
Thieme Verlag,Stuttgart,1999,Vol. E10a,pp. 76±78.
[5] W.W. Schmiegel,Organic fluoropolymers,in: M. Hudlicky,
A.E. Pavlath ꢀEds.),Chemistry of Organic Fluorine Compounds
II,American Chemical Society,Washington,DC,1995,pp. 1101±
1118.
3
4
CDCl3) d 1.21 ꢀdd, J ˆ 6:3 Hz, J ˆ 1:3 Hz,3H),1.81±
1.93 ꢀm,1H),2.19±2.26 ꢀm,1H),3.59±3.65 ꢀm,1H),3.68±
19F NMR ꢀ376.2 MHz,
3.80 ꢀm,4H),4.20±4.46 ꢀm,3H);
CDCl3) À80.3 ꢀ1F,OCF ), À81.6 ꢀ3F,Cꢀ=O)CFꢀCF )O),
2
3
[6] J.H. Holloway,J. Fluorine Chem. 104 ꢀ2000) 3.
[7] C.G. Fritz, S. Selman, US Patent 3,291,843 ꢀ1966).
[8] A.E. Feiring,Addition of fluorine and other elements,in: M.
Hudlicky,A.E. Pavlath ꢀEds.),Chemistry of Organic Fluorine
Compounds II,American Chemical Society,Washington,DC,
1995,p. 83.
À82.4 ꢀ3F,OCF CF2CF3), À86.7 ꢀ1F,OCF ), À130.0 ꢀ2F,
2
2
OCF2CF2CF3), À132.0 ꢀ1F,Cꢀ=O)CFꢀCF 3)O); high resolu-
‡
‡
tion mass spectrum ꢀCI ) 513.0112 ꢀ[M ‡ H] ,calculated
for C13H1435Cl2F11O4: 513.0094).
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4.2.5. Perfluoro[2-13,4-dichlorobutoxy)propyl
2-propoxypropionate] 115h) and perfluoro[2-
12,4-dichlorobutoxy)propyl 2-propoxypropionate] 115h0)
Fluorination of 11h was carried out in manner similar to
the synthesis of 15d. The product was quantitatively analyzed
by 19F NMR ꢀ376.2 MHz,CDCl 3); 15h ꢀ63%): À64.7 ꢀ2F, l),
À76.5 to À80.0 ꢀ1F, i), À80.0 to À81.0 ꢀ3F of h and 1F of c),
À82.2 ꢀ3F, a), À82.5 ꢀ3F, e), À82.0 to À82.9 ꢀ1F, i), À86.4 to
À88.1 ꢀ2F of f and 1F of c), À117.0 to À119.7 ꢀ2F, j), À130.4
ꢀ2F, b), À131.9 ꢀ1F, k), À132.3 ꢀ1F, d), À145.9 ꢀ1F, g); 15h0
ꢀ32%): À65.7 to À67.2 ꢀ2F, s), À76.5 to À80.0 ꢀ2F, p), À81.0
to À81.3 ꢀ3F of o and 1F of c), À82.0 to À83.0 ꢀ6F, a and e),
À86.5 to À88.5 ꢀ2F of m and 1F of c), À112.5 to À116.0 ꢀ2F,
r), À130.5 ꢀ2F, b), À131.9 to À132.4 ꢀ1F, d), À136.5 ꢀ1F, q),
[12] M.-H. Hung, S. Rosen, US Patent 5,350,497 ꢀ1994).
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‡
À145.9ꢀ1F,n);highresolutionmassspectrumꢀEI )726.8797
ꢀM À F,calculated for C 1335Cl2F23O4: 726.8806) ꢀFig. 2).
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ꢀ1990) 47.
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97.
Acknowledgements
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7117.
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We would like to thank Professor Chambers for helpful
discussions.
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Baasner,H. Hagemann,J.C. Tatlow ꢀEds.),Methoden. Org. Chem.
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