Note: Descriptions are shown in the official language in which they were submitted.
~2~3808
TI TJIE
NOVEL FLUORODIOXOLES AND FLUORODIOXOLE POLYMERS
BACKGROUND OF T~E I~VENTION
This invention relates to certain novel
fluorodioxoles, their polymers, and processes or
making the fluorodioxoles.
Various dioxolanes having the following
formula 1 are known from German Patent 2,604,350 to
Stanford Research Institute:
CHX - CHY
--C~ (1)
F F
where each of X and Y may be F or Cl.
Dioxolanes corresponding to formula ~2),
below, are reported in U.S. Patent 3,749,791 to
Terrell et al.:
CHX - C~X'
~ C~ (2,
CF -CF
where X is Cl or F, and X' is H, Cl, or F.
The intermediate 2,2-bis(trifluoromethyll-
1,3-dioxolane is known from U.S. Patent 2,925,424 to
Simmons.
Dechlorination of
2,2-bis(trifluoromethyl)-4,5-dichloro-4,5-difluoro-1,3-
dioxolane to the corresponding perfluorodioxole has
been reported by Resnick in U.S. Patents 3,865,845
and 3,978,030.
That perfluorodioxole has been found to form
both homopolymers and copolymers (especially with
tetrafluoroe,hylene) which have interesting chemical
and physical properties (e.g., chemical inertness to
hydrogen fluoride, optical clarity, ability to form
films). It can be speculated that simpler and~or
cheaper fluorodioxoles also would be capable of
forming useful homopolymers and copolymers.
... .., .,- ~
~2~3~0~
S UM~ARY OF THE .I NVENTIO~
According to the present invention, there is
provided a class of fluorodioxoles having the
following formul.a (3):
CY = cæ
C ~ (3)
R R
in which Y is hydrogen or chlorine; Z is hydrogen,
fluorine, or chlorine; and R is fluorine or the
trifluoromethyl group; with the proviso that when R
is trifluoromethyl, only one of Y and Z can be
hydrogen or chlorine.
These fluorodioxoles are useful monomers for
the preparation of homopolymers and copolymers having
a wide range of potential applications. This
invention also includes such polymers as well as
certain novel polymers of known dioxoles. Generally,
the monomers from which the novel polymers of the
present invention are made can be represented by the
same formula ~3) in which Y, Z and R have the same
meaning as above, but the above proviso no longer
applies.
DETAILED DESCRIPTIO~ OF THE I~VENTION
The Pluorodioxoles of the present inve~nt.ion
can be conveniently made by ~echlorination of the
corresponding 4,5-dichlorodioxolanes with magnesium
in the ~resence of a catalytic amount of iodine and
of a water-soluble mercury salt or metallic mercury,
as shown in the following equation.
CClY - CClz
C ~ Mg, I2 (3) + MgC12 ,
R R Hg or Hg
(4)
Where R, Y, and Z have the same meaning as
in Formula (3), above.
~?38~8
This dechlorination reaction preferably is
carried out in solution in tetrahydrofuran, For
maximum production rate, an excess of magnesium is
employed in this reaction, the preferred amount heing
1.1 to 8 gram-atoms of magnesium per two grarn-atoms
of vicinal chlorine to be removed. However, for
maximum yield ~f dioxole, less than stoichiometric
amounts may be desirable to minimize side reactions.
Mercury salts suitable in this reaction include, for
e~ample, mercuric chloride, acetate, and nitrate.
Metallic mercury, when used, forms in situ an amalgam
with magnesium. However, an amalgam can be prepared
separately in advance. The amount of mercury need
not be large. For example, a weigh~ of mercuric
chloride about equal to the weight of iodine, in turn
equal to about 1% o~ the weight of magnesium usually
is sufficient. A slightly larger amount of metallic
mercury may be advisable to permit more effective
agitation and thus easier amalgam formation.
Although some 4,5-dioxolanes represented by
the above formula (4) are known, as discussed
earlier, those represented by formula (5), below are
believed to be novel:
CYCl-CFCI
`C'
R R (5~
in which R is fluorine or trifluoromethyl, and Y is
hydrogen or chlorine.
All the fluorodioxoles of this invention
copolymerize with tetrafluoroethylene (TFE) to tough,
crystalline copolymers suitable ~or use as a
dielectric in electrical and electronic equipment.
In these crystalline copolymers the fluorodio~ole
usually is present in an amount o~ about 12 mole
percent or less. When the fluorodio~ole content
~2Q3l3V8
increases beyon~ 12 mole percent, the copolymers
become amorphous. ~aturally, the 12 mole percent
level is not a sharp line of demarcation, since
copolymers having some crystallinity may exist ~bove
5 it, and significantly amorphous co~olymer m~y exist
below it. However, one can expect that a large
majority of copolymers having less than 12 mole % of
a fluorodioxole (3) will be crystalline, and a large
majority of those containing more than 12 mole ~ of
10 such a fluorodioxole will be amorphous. The
- amorphous copolymers are tough and at moderate
molecular weight soluble in various organic liquids,
such as 1,1,2-trichloro-1,2,2-trifluoroethane and
Fluorinert* Electronic Liquid FC-75 t3M Company) and
> 15 are particularly suitable for finishes and coatings
that are chemically inert and are stain and weather
resistant. Fluorodioxoles (3) in which each of Y and
_ Z is chlorine could not be incorporated into a
copolymer with TFE at a high enough level to result
~- 20 in an amorphous copolymer. Those copolymers that
were made were crystalline.
Fluorodioxoles (3) form with vin~lidene
fluoride (~2) and TFE strong, plastic and
elastomeric terpolvmers suitable for
corrosion-resistant seals, gaskets, and linings.
-_ Finally, the fluorodioxoles corresponding to
formula (3) in which Y is hydrogen and Z is hydrogen
-. or fluorine form homopolymers, which are tough,
~- amorphous resins suitable for transparent glazing
.
materials, especially as sight glas~es in chemically
corrosive uses employing hydrogen fluoride.
In addition to the novel dioxoles of Formula
3 as defined therein, ~ioxoles in which both X and Y
are hydrogen or chlorine, and R is trifluoromethyl
can be made by ~he same general techniques but are
*denotes trade mark
-
-
~ 3~
not believed to be novel. Those dioxoles also form
novel and valuable copolymers; the dioxoles in which
X is hydrogen, and Y is hydrogen or fluorine alsQ
form homopolymers.
Broadly, this invention includes, therefore,
homopolymers of the novel dioxoles of this invention
as well as copolymers of the dioxoles represented by
for~ula (3) in which Y is hydrogen or chlorine; Z is
hydrogen, fluorine, or chlorine; and R is fluorine or
trifluoromethyl with tetrafluoroethylene and
terpolymers with tetrafluoroethylene and vinylidene
fluoride.
This invention is now illustrated by
representative examples of certain preferred
embodiments thereof, wherein all parts, proportions,
and percentages are by weight unless otherwise
indicated. Further, unless shown otherwise, all
reactions, separations, distillations, and storage
were carried out in a nitrogen atmosphere.
3S
3~?0~
TA~LE I
SUM~ARY OF PREPARATION OF DIOXOLES OF
FORMUI.A ~3) AND DIOXOLAN~S OF FORMULA (4)
Example Compound Compound Substituents
No. No. Y Z R
Prep. of:
lA (4a) Cl F CF3
lB (3a) Cl F CF3
lB (3b) F H CF3
lB (4b) F H CF3
lC (3a) Cl F CF3
lD (3b) F H CF3
8A (4c) H H CF3
8A (4d) Cl H CF3
8A (4e) Cl Cl CF3
8B (3c) H H CF3
8B (3d) Cl H CF3
8B ~3e) Cl Cl CF3
8C (3d) Cl H CF3
15A ~4f) Cl F . F
15B (3f) Cl F F
153 ~3g) F H F
15B (4g) F H F
16A/B (4g) F H F
17 (3g) F H F
22 (4h) H H F
22 (3h) H H F
25 (4i) Cl H F
(3i) Cl H F
28 (3j) Cl Cl F
28 (4j) Cl Cl F
,..~
3808
TABLE II
SUMMARY OF EXAMPLES --POLYMERIZATION
Example Monomer Polymer Properties
No. Compound No. Comonomer ~ol ~ Dioxole, Tm,* Tg**
2 ~3b) - 100%, Tg>300C
3 (3b) TFE 5.2%, Tm=266 ~ 320C
4 (3b) TFE 28.8%, Tg=58C
(3b) TFE 2.4%, Tm=307C
(3a) TFE 3.1%, Tm=235C
7 (3a) TFE/VF2 5.3%,14.3% TFE; Tm=131C
9 (3c) TFE 6.9%, Tm=253C
(3c) TFE 46.3%, Tg=61C
11 (3c3 TFE/VF2 7.9%, 36.4~ TFE Elast.,
Tm=114C
12 (3c) - ~00~
15 13 (3d) TFE 5.9%, Tm=269C
14 (3c)/(3d) TFE 8.6~ (3c)/6.2% (3d),
Tg=54C
18 (3g) TFE 4.0~, Tm=274C
19 (39) - 100%
20 20 (3f) TFE 10.5%, Tg=61C
21 (3f) TFE/VF2 9~9~ t 27,7% TFE; no Tm
23 (3h) - 100
24 (3h) TF~ 7
26 (3i) TFE 6%
27 (3e) TFE 0.6%, Tm=312C
29 (3;) TFE 1.4~, Tm=3109 297C
* melt temperature (indicates that the polymer has
crystallite regions)
** glass transition temperature (indicates that the
polymer is amorphous)
Example 1
Preparation of 2,2-bis(trifluoromethyl3-
4-chloro-5-fluoro-1,3-dioxole, (3a),
2,2-bis(trifluoromethyl)-4-fluoro-1,3-di~xole, (3b~,
and the corresponding dioxolanes (4a) and (4b).
,
38~3
A. 2,2-Bis~trifluoromethyl)-4,4,5-trichloro-
5-fluoro-1,3 dioxolane, (4a).
A 330 mL Hastello~ C lined shaker t~be was
charged under anhydrous conditions with 100 g (0.286
mole) of 2,2-bis(trifluoromethyl)-4,4,5,5-tetrachloro-
1,3-dioxolane (4e) and 8.6 9 tO.0432 mole) of
antimony pentachloride; the tube was then chilled to
about -50~C, and 20 9 (1 mole) of hydrogen fluoride
was introduced into it. The tube was mounted in a
horizontal shaker, agitated for 5 hours at 70C, then
chilled in wet ice, 510wly vented, and opene~. The
tube contents were dumped into wet ice. The liquid
product W3S separated from the ice water, washed
twice with 50 mL portions of cold water, then with 20
mL of a 10~ aqueous sodium carbonate solution. There
was obtained 83.5 9 of a clear, colorless liquld
product of which approximately 93% was the desired
2,2-bis(trifluoromethyl)-4,4,5-trichloro-5-fluoro-1,3-
dioxolane, (4a).
The product was distilled at atmospheric
pressure on a 0.76 m spinning band column; a small
amount of 2,2 bis(trifluoromethyl)-4,5-dichloro-4,5-
difluoro-1,3-dioxolane (about 2~ of the product)
boiling at 85-86C distilled fir~t, followed by the
2,2-bis(trifluoromethyl)-4,4,5-trichloro-5-fluoro-1,3-
dioxolane, b.p. 115C, which was obtained as a
colorless, clear liquid in purity exceeding 99%.
Both infrared spectroscopy and Fluorine-l9 nuclear
magnetic resonance spectroscopy.were consistent with
this chemical structure.
The pot residue was largely starting
material, approximately 5% of the total mixture from
the shaker tube run.
B. ~echlorination of 2,20bis(trifluoro-
methyl)-4,4,5trichloro-5-fluoro-
1,3-dioxolane, (4a).
*denotes trade mark
~2Q38~
A 300 mL, 3-neck glass flask equipped with
magnetic stirrer, thermometer, Vigreux column, still
head to a 100 mL receiver, and dry ice trap under 1~0
kPa of nitro~en was charged with 165 mL of
l-propanol, 42~6 g (0.651 mole) of zinc dust, and 1.4
g (0.0109 mole) of zinc chloride. The mixture was
stirred while being heated to 98C over a 21 ~inute
period; when this temperature was reached,
2,2 bis(trifluorome~hyl)-4,4,5-trichloro-5-fluoro-1,3-
dioxolane, 72.0 g (0.217 mole), was introduced intothe refluxing mixture via a syrinye pump at
0.33 mL/minute. Thirty-five minutes later the head
temperature fell to S9C, and distillation of the
product was started. Total addition time was 127
minutes. Total distillation time was 268 minutes,
during which time the head temperature decreased to a
minimum of 55C. The distillate, 60 mL, contained
some l~propanol which was extracted with water,
leaving 47.7 9 of a clear, colorless liquid
containing about 52~ of 2,2-bis(trifluoro-
methyl)-4-chloro-5-fluoro-1,3-dioxole, (3a), 25% of
2,2-bis(trifluoromethyl)-4-fluoro-1,3-dioxole, (3b),
and 22~ of 2,2,-bis(trifluoromethyl)-4,5-
dichloro-4-fluoro-1,3-dioxolane ~4b) as a mixture of
30~ cis and 70~ trans isomers.
The crud~ reaction product was fractionated
at atmospheric pressure on a 0.51 m spinning band
column. 2,2-Bis(trifluoromethyl)-4-fluoro-1,3-
Zioxole, (3b), b.p. 44-45C, polymerizes
spontaneously at room temperature when pure. It was
therefore collected in a receiver maintained at -80C
and stored in a dry ice chest. 2,2-Bis~trifluoro-
methyl)-4-chloro-5 fluoro-1,3-dioxole~ (3a),
distilled at 56C; this monomer did not polymerize
spontaneously at room temperature. The cis/trans
3~0~3
mixture of 2,2-bis~tri-fluoromethyl)-4,5-dichloro-
4-fluoro-1,3-dioxolane, (4b), distilled within the
range of 8~-90C.
The IR, F-l9 and proton NMR spectra, and
mass spectrometry support the above che~ical
structures.
C. Alternate dechlorination of
2,2-bis(trifluoromethyl)-4,4,5-trichloro-5-fluoro-1,~-
dioxolane, (4a~.
The equipment described in the above section
B was charged with 80 mL of tetrahydrofuran, 10.8 g
(0.444 mole) of magnesium turnings, 0.2 g of mercuric
chloride, and 0.2 y of iodine and heated to 66C
(iodine color disa~pears). 2,2-Bis(trifluoro-
methyl)-4,4,5-trichloro-5-fluoro-1,3-dioxolane,
33.1 g (0.1 mole), was added by means of a syrinqe
pump at the rate of D~16 mL/minute over a period of
110 minutes. Distillation was started 41 minutes
after the addition; the head temperature remained at
54-5SC during the re~,ainder of the addition. The
distillation was stopped after 2.5 hours, and the
distillate was extracted with water to remove some
tetrahydro~uran. The extracted clearl colorlPss
liquid was found by gas chromatography to contain
ahout 95% of 2,-2-bis(trifluoromethyl)-4-
chloro-5-fluoro-1,3-dioxole, (3a); the
2,2-bis(trifluoromethyl)-4-fluorool,3-dioxole, (3b),
amounted to only 1%.
Do Alternate preparation of 2,2 bis(tri-
fluoromethyl)-4-fluoro-1,3-dioxole, (3b).
Using the same equipment, except for a
smaller, 100 mL flask, a mixture of 30 mL of
tetrahydrofuran, 3.6 g of magnesium turnings, 0.~ g
of mercuric chloride, and 0.1 g of iodine was heated
to reflux. 2,2-Bis~trifluoromethyl)-4,5-dichloro-4-
. .
~2~3808
fluoro-1,3 dioxolane, (4b), 10 g, (prepared as
described in Section B, above) was then introduced
into the flask at approximately 0.19 mL/minute over a
34 minute period. Distillation was started 21
minutes a~ter the addition was completed and
continued until 20 mI. of cold distillate was
recovered. This was extracted with ice water to
remove tetrahydrofuran. The remaining product was
2,2-bis~trifluoromethyl)-4-fluoro-1,3-dioxole, (3b).
Example 2
~ omopolymerization of 2,2-bis(tri-
fluoromethyl)-4-fluoro-1,3-dioxole, (3b).
This monomer, 4 6 9, (99.88% pure by sas
chromatography) was placed at 25C in a small,
tightly capped vial under room lighting conditions.
Within a few hours the viscosity of the clear liquid
increased to that of a light syrup, and overnight a
solid, clear, colorless plug of polymer formed on the
bottom of the vial.
A small sample of the monomer-polymer syrup
was evaporated on a salt plate to remove the residual
monomer and form a film of the homopolymerO The
infrared absorbance spectrum of this film was
consistent with the molecular structure of a
homopolymer of 2,2-bis(trifluoromethyl~-4-fluoro-
1,3-dioxole, (3b).
The plug was placed in a vacuum oven at
110-120~C to remove residual monomer, and then a
sample was examined by Differential Scanning
Calorimetry between room temperature and 300C.
There were no second order transitions or melting
points in this region, indicating that the
homopolymer was amorphous and that its Tg was above
300~C.
11
~2Q38~8
Example 3
Crystalline copolymer of 2,2-bis(trifluoro-
methyl)-4-fluoro-1,3-dioxole, (3b~, and TFE.
A 110 mL stainless steel shaker tub~ was
charged with a cold solution containing 100 g of
1,1,2-trichloro-1,2,2-trifluoroethane, 1.0 g of the
dioxol~, and 0.03 q of bis(4-t-butylcyclohexYl)
lperoxydicarbonate; the tube was chilled to -50C and
alternately evacuated and flushed with nitro~en ~hree
times. The evacuated tube was then charged with lO g
of tetrafluoroethylene and agitated in a horizontal
shaker. The temperature was held at 55C for two
hours and then at 65C for two hours. After cooling
the tube and venting, the resulting suspension of
copolymer in 1,1,2-trichloro-1,2,2-trifluoroethane
was recovered. The solvent was distilled off, and
the polymer was dried to give ~.7 q of white, solid
granules. A portion of these was pressed at 300~C
into a tough, self-supporting film. The infrared
spectrum of the film showed absorbancies
characteristic of a tetrafluoroethylene/2,2-bis(tri-
fluoromethyl)-4-fluoro-1,3-dioxole copolymer.
Differential Scanning Calori~etry showed a major,
broad, crystalline melting point at 266C; there also
25 was a minor melting point at 320C. Infrared and
F-l9 NMR spectra support the copolymer structure
containing 94~8 mole ~ of tetrafluoroethylene and 5.2
~ole % of 2f 2-bis(trifluoromethyl)-4-fluoro-
1,3~dioxole, (3b).
30Example 4
Amorphous copolymer of 2,2-bis(trifluoro-
methyl)-4-fluoro-1,3-dioxole, t3b), and TFE.
A shaker tube was charged with 100 g of
1,1,2-trichloro-1,2,2-trifluoroethane, 0.03 g of
35 bis(4-t-butylcyclohexyl) peroxydicarbonatei 5.0 g
12
':,
" ~2~3808
(0.022 mole) of the dioxole, and 5.0 g (0.05 mole) of
TFE. Polymerization was carried out at 55~ and
65C. After separating and ~rying the product, 4.5
of a white solid polymeric product was obtained. A
5 portion of the product was pressed at 230~C into
thin, tough, clear, colorless, self-supporting
films. The infrared and F-l9 N~5R sPectra established
the product to be a copolymer containing 71.2 mole %
of TFE and 28.8 mole ~ of the dioxole. Differential
Scanning Calorimetry showed a Tg at 58C but no
melting point, thereby indicating that the copolymer
was amorphous.
Example S
A high melting crystalline copolymer of
2,2-bis(trifluoromethyl)-4-fluoro-1,3-dioxole, (3b)
and TFE.
A shaker tube was charged with 100 g of
1,1,2-trichloro 1~2,2-trifluoroethane, 0~03 g of
bis(4-t-butylcyclohexyl) peroxydicarbonate, 0.5 9
(0.0022 mole) of the dioxole, and 1~ g (0.1 mole) of
TFE. Polymerization was carried out at 55 and
65C. ~fter separating and drying the product, 9.4 g
of a white, solid polymer was obtained. A portion of
the polymer was pressed at 330C into thin, tough,
colorless, transparent, self-supporting films~ The
infrared and F-l9 NMR spectra were consistent with
copolymer of 97.6 mole ~ TFE and 2.4 mole ~ of
2,2-bis(trifluoromethyl)-4-fluoro-1,3-dioxole.
Differential Scanning Calorimetry showed a relatively
sharp ~elting point at 307C, thus indicating the
crystalline nature of the polymer.
ExamPle 6
A crystalline copolymer of 2,2-bis-
(trifluoromethyl)-4-chloro-5-~luoro-1,3-dioxole,
(3a), and TFR.
13
~Z~38[)~3
14
A shaker tube was charged with 100 g of
1,1,2-trichloro-1,2,2-trifluoroethane, 0.03 g of
bis(4-t-butylcyclohexyl) peroxydicarbonate, 1.5 g
(0.0058 mole) of the dioxole and 10 g of q'FE, and
polymerization was carried out at 55 and 65C.
After separating and drying the product, 4.3 g of a
white, solid polymer was obtained. A portion of the
polymer was pressed at 300C to give tough, thin,
colorless, clear, self-supporting films. Infrared
and F-l9 NMR spectra support the structure of a
copolymer containins 96.9 mole ~ of TFE and 3.1
mole % of 2,2-bis(trifluoromethyl)-4-chloro-5-
fluoro-1,3-dioxole, (3a). Differential Scanning
Calorimetry showed a melting point at 295C,
indicating the crystalline nature of the polymer.
Example 7
A terpolymer of 2,2-bis(trifluoromethyl)-4-
chloro-5-fluoro-1,3-dioxole, (3a), vinylidene
fluoride, and TFE.
A shaker tube was charged with 100 g of
1,1,2-trichloro-1,2,2-trifluoroethane, 3.0 g of the
dioxole, 0.03 g of bis(4-t-butylcyclohexyl~
peroxydicarbonate, 6.0 g of vinylidene fluoride, and
6.0 g of TFE. Polymerization was carried out at 55
and 65C for 4 hours under autogenous pressure.
After separating and drying the product, 3.6 g of a
white, solid polymer was obtained. A portion of this
polymer was pressed at 230C into thin, tough, clear,
self-supporting films. Infrared and F-13 NMR ~pectra
identified the polymer as a terpolymer containing
14.3 mole % of TFE, 80.4 mole % of vinylidene
fluoride, and 5.3 mole % of the dioxole.
Differential Scanning Calorimetry showed a melting
point at 131C, thus demonstrating the crystalline
character of the polymer.
14
Q3~08
lS
Example 8
Preparation of 2,2-bis(trifluoromethyl)-
1,3-dioxole, (3c), 2,2-bis(trifluoromethyl)-4-
chloro-1,3-dioxol~, (3d), and 2,2-bis(trifluoro~
5 methyl)-4,5-dichloro-1,3-dioxole, (3e).
A. Synthesis of 2,2-bis(trifluoromethyl)-
4,5-dichloro-1,3-dioxolane, (4c), 2,2-bis(tri-
fluoromethyl)-4,4,5-trichloro-1,3-dioxolane, (4d),
and 2,2-bis(trifluoromethyl)-4,4j5,5-tetrachloro-
1,3-dioxolane, (4e).
A 300 mL, 3-neck round hottom flask equipped
~ith a magnetic stirrer, chlorine gas inlet,
thermometer r and a water condense topped by a dry
ice condenser communicating with a drying tower and
then with a water scrubber was charged with 210 g
(1.0 mole) of 2,2-bis(trifluoromethyl)-1,3-dioxolane.
After purging the system with nitrogen, chlorine was
passed into the solution at such a rate as to
maintain a yellow coloration of the solution. The
stirred mixture was irradiated with a 275 watt
General Electric sun lamp so as to maintain a
reaction temperature for the most part ~n the range
of 46-72C for 4.5 hours. The concentration of the
starting dioxolane in the reaction mixture had
dropped by then to approximately 0.1%, and the
reaction was terminated. Residual chlorine and
hydrogen chloride were removed with a water
aspirator, leaving a colorless, clear liquid weighing
289 g and containing the di-, tri-, and tetrachloro-
3~ derivatives (4c), (4d), and (4e), as confirmed byN.~R, mass spectrometry, and gas chromatographic
analyses.
B. Dechlorination of the di-, tri , and
tetrachlorodioxolanes obtained in step A, above.
~Q3l308
A 500 mL, 3-neck, round bottom flask
equipped with a magnetic stirrer, a syringe pump
inlet, a thermometer, a 15-cm still leading to a 100
mL receiver and then to a nitrogen tee and a bubbler
was charged with 98.1 g (1.5 moles) of zinc dust,
3.0 9 (0.022 mole) of zinc chloride, ~nd 300 mL of
n-b~tyl alcohol. A syringe pump was charged ~ith
139.5 g of the chlorinated dioxolanes from step A.
After the flask contents were brought to 115C, the
chlorinated dioxolanes were pumped into the flask at
0.33 mL/minute. The addition was completed in 224
minutes. Twenty minutes after the start of the
addition, distillation began at a rate of about 15-20
mL/hour. The head tempexature then was 79~-80C but
during the distillation decreased to 75C and at the
end was 116C; 119.8 g of product containing butyl
alcohol was distilled. The produc~ distribution was
about 21% o~ 2,2-bis(trifluoromethyl)-1,3-dioxole,
(3c), 47% of 2,2-bis(trifluoromethyl)-4-chloro-
1,3-dioxole, (3d), and 30~ of
2,2-bis(trifluoromethyl)-4,5-dichloro-1,3-
dioxole, (3e). The crude product was fractionated at
atmospheric pressure on a 0~76 m spinning band column
to provide each dioxole as a clear, colorless liquid
2S having a ~urity of at least 99~:
2,2-bis(trifluoromethyl)-1,3-dioxole, ~3c), b.p.
67C; 2,2-bis(trifluoromethyl)4-chloro-1,3-dioxole,
~3d), b.p. 76C; and 2r2-bis(trifluoromethyl)-
4,5-dichloro-1,3-dioxole, (3e)~ b~p. 85C. The
infrared, F-19 and proton N~R, and mass spectrometry
data for these dioxoles support their molecular
- structures.
C. Alternate synthesis of 2,2-bis~trifluoro-
methyl)-4-chloro-1,3-dioxole, (3d).
16
,~,.
~2G3808
17
A 100 mL, 2-neck, round-bottom glass flask
equipped with magnetic stirrer, thermometer, Vigreux
column, still head, and receiver was charged under a
nitrogen blanket with 40 mL of di(ethylene glycol)
dimethyl ether t 9 . 8 g of crude
2,2-bis(trifluoromethyl)-4,5-dichloro-1,3-dioxolane,
(4c), and 6.7 g of solid potassium hydroxide. The
~lask contents were heated at 141C for 2 hours
during which time the 2,2-bis(trifluoro-
methyl)~4-chloro~1,3-dioxole, (3d), distilled over.
Purified by gas chromatography, the product had the
same retention time and infrared spectrum as an
authentic sample of 2,2-bis(trifluoromethyl)-
4-chloro-1,3-dioxole, (3d).
Example 9
A crystalline copolymer of 2,2-bis(tri-
fluoromethyl)-1,3-dioxole, (3c) and TFE.
A shaker tube was charged with 100 g of
1,1,2-trichloro-1,2,2-trifluoroethane, 0.03 g of
bis(4-t~butylcyclohexyl) peroxydicarbonate, 1.5 g
(0.0072 mole) of the dioxole, and 10 g (0.1 mole) of
TFE. Polymerization was carried out at 55 and
65C. After separating and drying the product, lO.S
g of a white, solid polymer was obtained. A portion
of the polymer was pressed at 300C into tough,
clear, colorless, self-supporting films. Infrared
and F-l9 N~R spectra established a copolymer
structure of 93.1 mole ~ of TFE and 6.9 mole ~ of
2,2-bis(trifluoromethyl)-1,3~dioxole, (3c).
Differential Scanning Calorimetry showed a melting
point a~ 253C, thereby establishing the crystalline
character of this polymer.
Example 10
An amorphous copolymer of 2,2-bis(tri-
fluoromethyl)-1,3-dioxole, (3c) and TFE.
17
120380B
18
A shaker tube was char~ed with ioo 9 of
1,1,2-trichloro-1,2,2-trifluoroethane, 4.2 g (0.02
mole) of the dioxole, 0.03 g of bis(4-t-butyl-
cyclohexyl) peroxydicarbonate, and 10 g o~ TFE.
Polymerization was carried out at 55 and 65C under
autogenous pressure for 4 hoursO ~fter separation
and drying, a white, solid polymer, 1.4 g, was
obtained. It was soluble in the trichlorotrifluoro-
ethane solvent; a clear, transparent, self-supporting
film was cast from this solution. Infrared and F-19
and proton N.~R spectra identified the copolymer as
containing 46.3 mole ~ of the dioxole and 53.7 .mole
of TFE. Differential Scanning C~lorimetry showed a
Tg at 61~C and other transitions at 113C and 246C;
there was no melting poin~, and the polymer was
therefore amorphous.
Exam~le 11
An elastomeric terpolymer of 2,2-bis(tri-
fluoromethyl)-1,3-dioxole, ~3c), vinylidene fluoride,
20 and TFE.
A shaker tube was charged with 100 g of
1,1,2-trichloro-1-2,2,-trifluoroethane, 3.0 9 ~0.0144
mole) of the dioxole, 0.03 g of bis(4-t-butyl-
cyclohexyl) peroxydicarbonate, 6~0 g ~0.094 mole~ of
25 vinylidene fluoride, and 6.0 ~ tOoO6 mole~ of TFE~
Polymerization was carried out under autogenous
pressure at 55 and 65C. After separation and
drying, a white, solid polymer, 6.4 ~, was obtained.
It was not soluble in the trichlorotrifluoroethane.
30 A portion of the polymer was pressed at 230~C to give
thin, tough, elas~omeric, clear, self-supporting
films. Infrared and F-19 NMR spectra identified the
terpolymer as containing 36.4 mole ~ of TFE, 55.7
mole % of vinylidene fluoride, and 7~9 mole % of
35 dloxole. Differential Scanning Calorimetry showed a
18
,sv
3~
19
melting point at 114C, indicating the crystalline
nature of the polymer.
Exam~le l2
Ho~opolymer of 2,2-bis(trifluoromethyl)-
1,3-dioxole, (3c).
The dioxole, 3.0 g, which had been kept in a
dry ice chest, was placed in a 10 mL closely capped,
clear, glass vial and allowed to stand ~t room
temDerature under laboratory ~luorescent lighting
conditions. After two weeks, a portion of the liquid
was placed on a salt plate and allowed to evaporate,
leaving a thin, transparent, clear, colorless solid
film. Infr~red analysis of this film was consistent
with the homopolymer structure.
Exam~le 13
A crystalline copolymer of TFE and 2,2~bis-
(trifluoromQthyl)-4-chloro-1,3-dioxole, (3d).
A shaker tube was charged with 100 g of
1,1,2-trichloro,1,2,2-trifluoroethane, 0.03 g of bis
(4-t-butylcyclohexyl3 peroxydicarbonate, 1.5 g
(0.00618 mole) of the dioxole, and 10 g (0.1 mole) of
TFE. Polymerization was carried out under autogenous
pressure at 55 and 65C. After separation and
drying, a white solid polymer, 5.0 g, was obtained.
A ~ortion of the polymer was pressed at 300C into
thin, tough, clear, self-supporting films. Infrared
and F-l9 NMR spectra showed the copolymer to contain
94.1 mole % of TFE and 5.9 mole % of the dioxole.
Differential Scanning Calorimetry showed a melting
~oint at 269C/ thus indicating the polymer to be
crystalline.
Example 14
An amorphous terpolymer of TFE with 2,2-bis-
~trifluoromethyl)-1,3-dioxolQ, (3c~ and
2,2-bis(trifluoromethyl)-4-chloro 1,3-dioxole,.(3d).
lg
., --
3808
A shaker tube was charged with 100 g of
1,1,2-trichloro-1,2,2-trifluoroethane, loO g of
2,2-his(trifluoromethyl)-1,3-dioxole, (3c), 2.0 g of
2,2-bis(trifluoromethyl)-4-chloro-1,3-dioxole, (3d3
0.03 9 of bis(4-t-butylcyclohexyl) peroxydicar~onate,
and 10 9 TFE. Polymerization was carried out under
autogenous pressure at 55 and 65C. After
separation and d~ying, 3 ~ of white, solid, polymer
granules were obtained. A portion of the polymer was
pressed at 300C to give thin, tough,
s~lf-supportingt colorless, clear films. The
infrared and F-l9 NMR spectra were consistent with a
terpolymer structure consisting of 85.2 mole % of
TFE, 8.6% of 2,2-bis(trifluoromethyl)-1,3-dioxole,
15 (3c~, and 6.2 mole`% of 2,2-bis(trifluoromethyl~-4-
chloro-1,3-dioxole, (3d). The Differential Scanning
Calorimetry analysis showed a Tg at 54C but no
melting point, thereby indicating the polymer to be
amorphous.
~xamPle 15
Preparation of 2,2,4-trifluoro-5~chloro-
1,3-dioxole, (3f) 2,2,4-trifluoro-1,3-dioxole, (3g),
and the corresponding dioxolanes (4f) and (4g)~
A. 2,2,4-trifluoro-4,5,5-trichloro-1,3-dioxolane
(4f)
A dry, 360 mL U~astelloyl' C lined shaker
tube was charged with 81.8 g (0.33 mole) of
2,2-difluoro-4,4,5,5-tetrachloro 1~3-dioxolane, (4~,
containing 9.0 g (0.03 mole1 of antimony
pentachloride. The tube was cooled, alternately
e~acuated and purged with nitrogen three times, and
charged with 22 g (1.1 mole) of hydrogen fluoride.
The tube was agitated and warmed to 40C over a
period of 1 hour~ heated under autogenous pressure
for 4 hours at 40C, then cooled to 0C, 510wly
.P~
~Q380l!~
21
vented, and opened. The contents were poured into
ice; the organic phase was separated from the aqueous
phase, extracted twice with distilled water and once
with an aqueous 10% sodium carbonate solution; 63.3 9
of crude product was obtained which contained about
3.9% of 2,2,4,5-tetrafluoro-4,5-dichloro-1,3-
dioxolane, B5.8% 2,2,4-trifluoro-4,5,5-tri-
chloro-1,3-dioxolane, t4f), and 8.1% of the starting
material. This product mixture was combined with
those of three other similar runs and separated by
distillation on a 0.76 m spinning band column;
2,2,4,5-tetrafluoro-4,5-dichloro-1,3-dioxolane boiled
at 45-46C; 2,~,4-trifluoro-4,5,5-trichloro-
1,3-dioxolane, (4f), at 84C; and the starting
material, 2,2-difluoro-4,4,5,5-tetrachloro-
1,3-dioxolane (4j), at 115C. Their purities were
greater than 99%. Both infrared and F-l9 NMR
spectroscopy confirmed their structures.
B. Dechlorination of 2,2,4-trifluoro-4,5,5-
trichloro-1,3-dioxolane, (4f).
A 300 mL 3-neck glass flask equipped with
magnetic stirrer, thermometer, Vigreux column with a
dry ice-cooled still head leading to a cold receiver,
trap, a nitrogen tee, and bubbler was charged w~th
76.7 g (1.17 gram-atoms) of zinc, 2.6 g ~0.019 mole)
of zinc chloride, and 175 mL of propanol The
stirred mixture was heated to 94C; then 89.~ g
~0.387 mole) of 2,2,4-trifluoro-4,5,5-
trichloro-1,3-dioxolane, (4f), was introduced from a
syringe ~ump at a rate of Q.33 mL/minute during 172
minutes. Distillation at a rate of abo~t 15 mL/hour
began 33 minutes after the start of the addition and
continued for 270 minutes; 65 mL of clear, colorless
distillate weighing 84.5 g and containing so~e
propanol was obtained. It was redistilled through a
21
~ZQ3808
0.76 m spinning band column with a dry ice-cooled
head. The prod~ct distribution was approximately
3.9% of 2,2,4-trifluoro-1,3-dioxole, (39), b.p. 10C;
71.7% of 2,2,4-trifluoro-5-chloro-1,3-dioxole, (3f),
b.p. 25-27C; and 24.3% of 2,2,4-trifluoro-4,5-
dichloro-1,3-dioxolane, (4g), b.p. 73C. The
in~rared, F-l9 and proton NMR spectra of these
compounds were consistent with the assigned
structures.
Example 16
Alternate synthesis of 2,2,4-trifluoro-
4,5-dichloro-1,3-dioxolane, (4q).
A. 4,4,5-trichloro-1,3-dioxolan-2-one.
A creased 3-neck, 300 mL, round bottom flask
equipped with magnetic stirrer, gas inlet tube,
thermometer, and water condenser topped by a dry ice
condenser leading to a trap and scrubber was charged
with 88.1 g of ethylene carbonate. The system was
purged with nitrogen and then dry chlorine gas was
introduced while irradiating the reaction vessel with
a 275 watt General Electric*Sun Lamp; the amount of
chlorine was sufficient to maintain a yellow color in
the solutionO The temperature ranged from 35C
during the initial part of the chlorination and up to
llS~C during the later part of the 6-hour reaction.
The reaction mixture was analy~ed by gas
chromatography techniques and, when all of the
4-chloro-1,3-dioxolan-2-one had been consumed, the
reaction was terminated. The product was principally
4,4,5-trichloro-1,3-dioxolan-2-one with les~er
amounts of 4,5-dichloro- and 4~4,5,5-tetrachloro-
derivatives. Two similar runs were made and ~he
products combined~
~O ~luorination of 4,4,5-trichloro-1,3-
35 dioxolan-2-one.
*denotes trade mark
22
~Z~38~)8
23
A shaker tube was charged with 113 g of
crude 4,4,5-trichloro-1,3-dioxolan-2-one, 18 g of HF,
and 194 g of SF4. After agitating 10 hours at
200C, the tube was cooled to 0C, and the product
was mixed with ice. The organic phase was separated
and neu~ralized by shaking with an aqueous potassium
carbonate solution and then distilled on a 0.76 m
spinning band column the ~irst fraction,
2,2,4,5-tetrafluoro-4,5-dichloro-1,3-dioxolane, b.p.
47-48C, was followed by the desired
2,2,4-trifluoro-4,5-dichloro-1,3~dioxolane, ~4g),
b.~. 69-73C. Infrared and F-19 NMR spectra were
consistent with this structure.
~xam~le 17
Preparation of 2,2,4-trifluoro 1,3-dioxole,
(3g~, by dechlorination of 2,2,4-trifluoro-4,5-
dichLoro-1,3-dloxolane, (4g).
A 100 mL, 3-neck, round bottom flask
equipped with magnetic stirrer, thermometer, Vigreux
still leading to a dry ice-cooled head, cold receiver
and trap, was charged under a nitrogen blanket with
3~6 g of magnesium turnings, 0.2 g of mercuric
chlorîde, 0.1 g of iodine, and 30 mL of
tetrahydrofuran. The mixture was stirred and heated
to 67C; 8.8 9 of 2,2,4-trifluoro-4,5-dichloro-
1,3-dioxolane, (4g), was then added at a rate of
0.092 mL/minute. After 20 2 mL had been added the
distillation began ~nd continued for 3 hours until 5
mL of distillate was obtained. The cold distillate
was extracted with ice water to remove some
tetrahydrofuran and there remained 4.7 g of product
which was largely 2,2,4-trifluoro-1,3-dioxole, (3g),
b.p. 10C.
This dioxole was purified by gas
35 chromatography; the infrared absorbance spectra, and
23
24
especially the absorbance in the region of 5.fi ~m, a~
well as its subsequent polymerization substan~iated
the assigned molecular structure.
ExamPle l8
A crystalline copolymer of tetrafluoro-
ethylene with 2,2,4~trifluoro-1,3-dioxole, (3g~u
A shaker tube was charged with 100 9 of
1,1,2-trichloro-1,2,2-tri~luoroethane, 0.8 g of the
dioxole, 0.03 9 of bis~4-t-~utylcyclohexyl)
peroxydicarbonate, and 10 g of TFE and heated at 55
and 65C or 4 hours. After separation of the
product and drying, 4.7 ~ of a white solid polymer
was obtained. A portion of this was pressed at 330C
to give thin, tough, self-supporting, colorless
films. The infrared and F-~9 NMR spectra showed the
copolymer composition to be 96.0 mole % TFE and 4.0
mole % dioxole. Differenti~l Scanning Calorimetry
showed a crystalline melting point at 274C.
E~m~le 19
Homopolymer of 2,2,4-trifluoro-1,3-dioxole,
~3g).
A 10 mL clear, glass vial was charged with
5.7 9 of lfl,2-trichloro-1,2,2-trifluoroethane,
0.001 9 of bis(4 t-butylcyclohexyl~ peroxydi-
carbonate, and G.S g of the dioxole, capped securely
and allowed to stand two days on the bench ~op at
about 25C exposed to the normal fluorescen~ light of
the laboratory. A por~ion of the solution was then
evaporated on a micro salt plate to give a ~lear,
3~ colorless, self supporting film which was identified
by it~ infrared spectrum to be the dioxole
homopolymer~
Example 20
An amorphous copolymer of TFE and 2~204 ~ri-
fluoro-S-chloro 1,3-divxole, ~3~)c
2~
12(~38015
A shaker tube was charged with 100 g of
1,lr2-trifluoro-1,2,2-trichloroethane, 1.7 g of the
dioxole, 0.03 g of bis(4-t-butylcyclohexyl) peroxy-
dicarbonate, and 10 g of TFE. Polymerization was
carried out at 55 and 65C under autogenous pressure
for 4 hours. After separation and drying of the
product, 1.8 g of a whitej solid polymer was
obtained. A portion of this was pressed at 300C to
give thin, tough, self-supporting, colorless clear
films. The infrared and F-l9 N~R spectra of this
polymer showed it to contain 10.5 mole % of the
dioxole and 89.5 mole ~ of TFE. Differential
Scanning Calorimetry showed a Tg of 61C; there was
no melting point.
lS Example 21
An amorphous, elastomeric terpolymer of TFE,
2,2,4-trifluoro-5-chloro-1,3-dioxole, ~3f), and
vinylidene fluoride.
A shaker tube was charged with 100 g of
1,1,2-trichloro-1,2,2-trifluoroethane, 2.1 ~ of the
dioxole, 0.03 g of his(4-t-butylcyclohexyl~ peroxydi-
carbonate, 6 g of vinylidene fluoride, and 6 9 of
TFE. Polymerization was carried out at 55 and 65C
over a 4 hour period under autogenous pressure.
After separating and drying, there was obtained 2.5 g
o~ white, solid polymer granules. A portion of this
polymer was pressed at 200C to give thin, elastic,
tough, self supporting, clear, colorless films.
~nfrared and F 19 NMR spectra showed the terpolymer
to consist of 27.7 mole % of T~E, 9.~ mole % of the
dioxole and 62.4 mole ~ of vinylidene fluoride.
Differential Scanning Calorimetry showed no melting
point, thus indicating an amorphous polymer~
~5
:o l
-~ ~203808
26
Example 22
Synthesis of 2,2-difluoro-1,3-dioxole, (3h).
A. 4,5-Dichloro-1,3-dioxolan-2-one
A 500 mL, 3-neck round-bottom flask equipped
5 with a nitrogen purge line, magnetic stirrer,
thermometer, and reflux condenser leading to a trap
and drying tower was charged with 88 g of ethylene
carbonate, 297 g of sulfuryl chloride, and 1.0 g of
azobisisobutyronitrile. After purging the assembly
0 with nitrogen, the stirred mixture was irradiated
with a Hanovia mercury vapor lamp at a temperature of
34-47C during the first 3 hours of the reaction.
During the next 7 hours, the temperature was
increased from 51 to 103C. During the final 3
hours of the reaction, the temperature was held in
the 95-107DC range.
After cooling to room temperature, the flask
was evacuated on a water aspirator to remove small
amounts of HCl. The flask contents were then
flash-distilled at a pressure of abou~ 266 Pa and a
pot temperature of up to 150C; 85.7 g of distillate
was collected. GC analysis of the distillate showed
it to contain approximately 86 3% of
4,5-dichloro-1,3-dioxolan-2-one, 8~8% of
4-chloro-1,3-dioxolan-2-one, and 3.1% of
4,4,5-trichloro-1,3-dioxolan-2-one.
B. 2,2-Difluoro-4,5-dichloro-1,3-dioxolane
(4h)
A 300 mL "Hastelloy" C shaker tube was
charged with 136.2 g of 4,5~dichloro-1,3-dioxolan-
2-one, 16.2 g of HF, and 194.4 g of SF4. The tube
was then heated to 150~C and agitated for 300 hours.
After the tube was cooled to 0C, it was slowly
vented and then its contents were dumped into ice.
The organic layer was separated and extracted twice
26
~121~3808
` 27
with 50 mL of distilled water. The product weighed
93 . O g and contained about 69% of
2,2,4-trifluoro-5-chloro-1,3-dioxolane and abollt 7
of 2,2-difluoro-4,5-dichloro-
5 1,3-dioxolane, t4h).
C. Dechlorination of 2,2-difluoro-4,5-di-
chloro-1,3-dioxolane (4h)
Equipment like that of Example 15B, except
that a 100 mL fl~.sk was used, was charged with 7.8 g
10 of zinc dust, 0.2 9 of zinc chloride, and 40 mL of
butyl alcohol. The stirreA mixture was h~ated to
114C; 6.5 ~ of crude 2,2-difluoro-4,5-
dichloro-1,3-dioxolane (4h) was then added ~y a
syringe pump at 0.092 mL/minute over a 52-min~te
lS period. Distillation began 20 minutes after the
beginning of the addition and continued for 94
minutes until 4.5 mL of distillate containing some
butyl alcohol was obtained. The distillate ~as
purified by ~as chromatography. The infrared
20 absorbance spectrum, especially the absorbance in the
region of 6.0S ~m, was consistent with the
2,2-difluoro-1,3-dioxole structure (3h).
E~mple 23
Homopolymer of 2,2-difluoro~1,3-dioxole,
(3h).
A shaker tube is charged with 3 9 of
2,2 difluoro-1,3-dioxole in 100 g of 1,1,2-trichloro-
1,2,2-trifluoroethane, and 0.005 9 of
bis~4-t butylcyclohexyl~ pero~ydicarbonate.
30 Polymerization is carried out at 55 and 6$C for 4
hours. After separating and drying the solid, white
polymer, 0.6 g, ~ portion of it is pressed at ~50C
to give a tough, clear, transpar~nt, self supporting,
t~in ~ilm, of the homopolymer, which i~ amorphous.
27
1~93~308
28
Example 24
A crystalline copolymer of
tetrafluoroethylene and 2,2-difluoro-1,3-dioxole,
(3h).
A shaker tube is charged with 1 9 of the
dioxole in 100 9 of 1,1,2-trichloro-1,2,2-trifluoro-
ethane, 0.03 g of bis(4-t-butylcyclohexyl)
peroxydicarbonate, and 10 g of TFE. Polymerization
is carried out ~t 55 and 65C. After separating and
drying the pro~uct, 9.9 g of white, granular, solid,
crystalline polymer is obtained. It contains
approximately 93 mole ~ TFE and 7 mole ~ of the
dioxole.
Exam~le 2~
Synthesis of 2,2-difluoro-4-chloro-1,3-
dioxole, ~3i).
This synthesis is carried out in the same
manner as that of Example 22, except that 106.7 g
(0.5 mole) of 2,2-difl~oro-4~4,5-trichloro-
1,3-dioxolane, (4i), prepared from
4,4,5-trichloro-1,3-dioxolan-2-one (Example 16A) is
the starting material. Rectification of the product
mix through a 0.76 m spinning band column gives
47.1 g of 2,2-difluoro-4-chloro-1,3-dioxole, t3i).
Example 26
A crystalline copolymer of TFE with
2 t 2-difluoro-4-chloro-1,3-dioxole, ~3i).
A shaker tube is charged ~ith 100 g of
1,1,2~trichloro-1,2,2-trifluoroethane containing 1 g
of 2,2-d-ifluoro-4-chloro-1,3-dioxole, (3i), 0.03 g of
bis(4-t-butylcyclohexyl) peroxydicarbonate, and 10 g
of TFE. Polymerization is carried out at 55 and
65C. After separating and drying the product, S.2 g
of a white solid gran~lar polymer is obtained. This
is pressed at 300C into a tough, self-supporting,
28
.! '
~Z~3~
2g
clear film. The polymer is crystalline and contains
approximately 94 mole % TFE and 6 mole ~ of the
dioxole.
Exa~ple 27
A Crystalline TFE/2,2-bis(trifluoromethyl)-4,5-
dichloro-1,3-dioxole, (3e), copolymer
A 110 mL ~haker tube was charged with 100 g
of 1,1,2-trichloro-lr2,2-trifluoroethane, 3.0 g of
the dioxole, 0.04 g bis(4-t-butylcyclohexyl)
pero~ydicarbonate, 10 9 of TFE and heated 3.5 hours
at 55 and 65~C under autogenous pressure. After
separation and drying the product, 4.3 g of a white
solid polymer was obtained. Differential thermal
analysis showed a crystalline melting point at 312C;
the infrared spe~trum of a film possessed the
absorbancies characteristic of the
TFE/2,2-bis(trifluoromethyl)-4,5-dichloro-1,3-dioxole
copolymer. By elemental analysis, the copolymer
contained 0.44~ chlorine which corresponds to 0.6
2~ mole percent of dioxole.
Exa~ple 28
Synthesis of 2,2-difluoro-4,5-dichloro-1,3-dioxole,
~3i)
A. Tetrachloroethylene Carbonate
A 1000 mL creased flask equipped with a
stirrer, thermometer and gas inlet tube, and topped
by water and dry ice condensers, was charged with
352.4 9 (4 moles) of melted ethylene carbonate. The
system was purged with nitrogen while ethylene
carbonate was stirred and heated to 50C. After
turning off the nitrogen, chlorine was introduced at
a rapid rate and when the solution turned yellow, a
sunlamp was l.it. The flow of chlorine and the
intensity of the light were adjusted so that the
solution remained yellow and the temperature did not
2~
~ l
~203808
exceed 80C during the first few hours of the
chlorination. Later on, the temperature was
increased to 100-120C.
The chlorination was continued until
intermediates were no longer present in the product,
as evidenced by periodic gas chromatographic
analysis. When the product was free of the mono-,
di-, and trichloro intermediates, it was distilled at
a reduced pressure on a water aspirator. After the
removal of chlorine and hydrogen chloride, the
distillation was continued using a high vacuum pump.
B. 2,2-difluorQ-4,4,5,5-tetrachloro-
1,3-dioxolane (4i)
A 360 mL "Hastelloy" C shaker tube was
charged with 113 g ~0.5 mole) of tetrachloroethylene
carbonate, closed under nitrogen, cooled in *ry
ice/acetoner evacuated, flushed with nitrogen,
reevacuated and then charged with 18 g (0.9 mole) of
HF and 194 g (1.8 mole) of SF4. The tube was then
agitated for 10 hours at 200C. Following this, the
tube ~as chilled in an ice-water bath and then slowly
vented to remove the excess of SF4 and HF. The
product was dumped from the tube into wet ice and
allowed to stand a day. The water-product mixture
was placed in a polyethylene separatory funnel, and
~he dioxolane (4;) was withdrawn into a polyethylene
Erlenmeyer flask, weighed, and stirred one hour with
10 mL of a 30% K2CO3 solution in water (the pH of
the aqueous phase must be alkaline). The dioxolane -
(4;) was then separated and bottled. The
3 2,2-difluoro-4,4,5,5-tetrachloro-1,3-dioxolane (4j3
was dried over R2CO3 and distilled at a reduced
pressure prior to use ~b.p. 126C at 101 KPa~. Fl9
NMR ~nd IR analyses supported the molecular structure.
81~ `
31
C~ Dechlorination of
2,2~d~fluoro~4,4,5,5-tetrachloro-1,3-di~xolane, l4j)O
~ 300 mL, 3-neck glass flask equipped with
magnet$c stirrer, thermometer, Vigreux column w~h a
water condenser to receiver, trap to a nitroge~ tee
and bubbler was ~harged with l-propanol, 175 mL; zinc
dust, 59.3 g; zinc ~hloride, 2.0 9~ After heating to
reflux, the 2,2-difluoro-4,4,5,5-tetrachloro-lt3-
dioxolane (4j), 74.3 9, was added by syringe pump at
0-33 mL/minute; The addition was complete in 148
minutes. Distillation was begun 40 minutes after the
start of the addition and continued for 6 hours until
72 m~ of distillate was collecte~. The pro~uct was
98.7% pure desired dioxole, (3j), at 100~ conversion
lS of the dioxolane; the distillate which containe~ some
propan~l was redistilled through a 0.51 m spinnin~
band column to separate the dioxole, (3j), b.p.
64-65~C, at a purity of 98.6%~ A 3.66 m x oO06~ m
diameter 30% Xrytox* perfluoroether (Du Pont Co.)
column at 60C was used in ~he analysis. The
infrared sRectrum was consistent with the structure.
~xample 29
A crystalline TFE/2,2-difluoro-4,5-dichloro-1,3-
dioxole, (3i), copolymer.
A 110 mL shaker tube was charged with 100 g of
1,1,2-tr;~.hlnro-1,2,2-~r;fl.l~),ueUlane, 1.8 g of the ~;o~
0.04 g of bis~4-_-butylcyclohexyl~ peroxydi~dlL~a~e, and 10 g
of tetr~fll~r~eU~lene and heated 4 hours at 60-65C. Afte~
s~d~dLion of the insoluble pLU~U1'L and dryLng, 2.4 g of a white
solid polymer was obt~ined. Differential Sc~nn;n~ ~lnr;mp.try showed
a major c~ystalline melting point at 310C and a ~ullor one at 297C.
F-l9 NMR analysis shohred the copolymer to onnt~;n 1.4 mole ~ of the
~;nxnl~ (3j). Both the infræed and F-l9 ~MR ~cLl~ agreed with
the copolymer ~LLU~LU1~.
This application is a division of c~Pn~;n~ l;c~tion
Serial No. 451 912, filed 1984 ~pril 12, which in turn is a division
of c.~n-l;n~ rl;c~ n Serial No~ 427 320, filed 1983 May 03.
*denotes trade mark
31
