CA1318327C - 2,2-difluoropropionic acid derivatives - Google Patents
2,2-difluoropropionic acid derivativesInfo
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Abstract
Abstract:
The invention relates to 2,2-difluoropropionic acid derivatives of the following formula XCH2CF2COY (I) wherein X is chlorine, bromine, iodine, a group of the formula:
R1O- (II) or R2COO- (III) wherein R1 and R2 are each an aliphatic or halogenated aliphatic hydrocarbon group having 1 to 8 carbon atoms or an aromatic hydrocarbon group having 6 to 8 carbon atoms optionally bearing at least one substituent, or a group of the formula:
X'CH2CF2CF2O- (IV) wherein X' is fluorine, chlorine, bromine, iodine, or the group of the formula: R1O- or R2COO- as defined above; and Y
is fluorine, a group of the formula:
-OR3 (V) wherein R3 is an aliphatic or halogenated aliphatic hydrocarbon group having 1 to 8 carbon atoms except for a perfluorohydrocarbon group, or an aromatic hydrocarbon group having 6 to 8 carbon atoms optionally bearing at least one substituent, or a grsup of the formula:
-OCH2Rf (V') wherein Rf is an aliphatic perfluorohydrocarbon having 1 to 7 carbon atoms. These derivatives are useful as solvents, catalysts, monomers, etc., and can be formed by ring opening of tetrafluorooxetane in the presence of a co-reactant by which the group X is introduced into the derivative.
The invention relates to 2,2-difluoropropionic acid derivatives of the following formula XCH2CF2COY (I) wherein X is chlorine, bromine, iodine, a group of the formula:
R1O- (II) or R2COO- (III) wherein R1 and R2 are each an aliphatic or halogenated aliphatic hydrocarbon group having 1 to 8 carbon atoms or an aromatic hydrocarbon group having 6 to 8 carbon atoms optionally bearing at least one substituent, or a group of the formula:
X'CH2CF2CF2O- (IV) wherein X' is fluorine, chlorine, bromine, iodine, or the group of the formula: R1O- or R2COO- as defined above; and Y
is fluorine, a group of the formula:
-OR3 (V) wherein R3 is an aliphatic or halogenated aliphatic hydrocarbon group having 1 to 8 carbon atoms except for a perfluorohydrocarbon group, or an aromatic hydrocarbon group having 6 to 8 carbon atoms optionally bearing at least one substituent, or a grsup of the formula:
-OCH2Rf (V') wherein Rf is an aliphatic perfluorohydrocarbon having 1 to 7 carbon atoms. These derivatives are useful as solvents, catalysts, monomers, etc., and can be formed by ring opening of tetrafluorooxetane in the presence of a co-reactant by which the group X is introduced into the derivative.
Description
13183~7 2,2-Difluoro~ropionic acid derivativ,es This application is a division of our copending Canadian patent application Serial No. 470,916 filed on December 21, 1~8~.
The present inventlon relates to Z,2-diflu~ro-propionic acid derivatives. More particul~rly, it relates to 2,2-difluoropropionic acid derivatives and a process for preparing t~e same from 2~2~3~3-tetrafluorooxetane (herein-after re~erred to as "tetrafluorooxetane").
2,2,3-Trifluoropropionyl fluoride is useful as an intermediate for the production of medic,nes and agricultu-ral chemicals and as a strong acid catalyst. Further, its ester derivative is useful as a solvent, and its dehydrogenated fluorinated derivative is useful as a monomer.
It is known that it can be obtained as one of many products prepared by fluorinating propionyl chloride with fluorine in the presence of a cobalt fluoride catalyst (cf. J. C. Tatlow et al, J. of Fluorine Chemistry, 1973(3), 329-30).
One object or the present invention is to provide , 20 a novel process for preparing 2,2,3-trifluoropropion~-l fiuoride.
Another object of the invention is to provide a novel 2,2-difluoropropionic acid derivatives.
Accordlng to the present invention, 2,2,3-tri-fluoropropionyl fluoride is prepared by conducting a ring opening reaction of tetrafluorooxetane in the presence of a catalyst. ,~
- 2 - l 3 ~ 83~7 Tetrafluorooxetane is a known compound and is easily synthesized by reacting tetrafluoroethylene and formaldehyde.
Specific examples of the catalyst to be used in the above reaction are alkali metal fluorides and Lewis acids.
Pre~erred alkali metal fluorides are sodium fluoride, potassium fluoride and cesium iluoride, and preferred Lewis acids are AlC13 and SbF5 The above reaction may be carried out either in a liquid phase or in a gaseous phase.
When the reaction is carried out in the liquid phasej an alkali metal fluoride is dissolved in an aprotic solvent (eg. diglyme, tetraglyme, acetonitrile, etc.), and tetrafluorooxetane is added-thereto.
The reaction temperature is usually from 80C to the boiling point of the solvent, preerably from 80 to 200C. The reaction time depends on the reaction tempera-` ture, the kind and amount of the catalyst, and is preferably from l to 24 hours.
In the liquid phase reaction~ the preferred catalysts are potassium fluoride and cesium fluoride. The amount of the catalys~ is at least a catalytic amount and preferably from l to 50% by mole based on the tetrafluorooxetane.
In the case of the gaseous phase reaction, when an alkali metal fluoride is used as the catalyst, the reaction temperature should not be higher than 500C, and preferably from 200 to 450C. At temperatures higher than 500C, tetra-fluorooxetane is dscomposed. Th~ reac~ion pressure may be .
.~
:
~ 3 ~ 1 3~ 8327 - atmospheric pressure or a pressure higher or lower than atmospheric pressure as long as the reaction system is kept in the gaseous state. The space velocity depends on other reaction conditions such as the temperature, pressure, the klnd and amount of the catalyst, and is preferably from 10 to 1,000 hr 1, The raw material may be diluted with an in-active gas such as nitrogen.
In the gaseous phase reaction, the catalyst is generally supported on a carrier (eg. activated carbon, asbestos, nickel oxide, silica gel, a molecular sieve, etc.). Of these, activated carbon is preferred.
When a Lewis acid is used as the catalyst, it may be dissolved in a solvent (eg. CH2C12, CHC13, CC14, etc.).
SbF5 does not necessarily require any solvent. The reaction temperature is usually from room temperature to 50C.
If tetrafluorooxetane is analogously ring opened in the presence of an appropriate coreactant, a novel 2,2-difluoropropionic acid derivative may be prepared.
` The novel 2,2-difluoropropionic acid derivative of the invention can be represented by the formula:
XcH2CF2COY (I) wherein X is chlorine, bromine, iodine, a group of the formula:
lO- (II) 25 or R2COO- (III1 ` .
:
,~
- 4 ~ 1 31 8327 wherein Rl and R2 are each an aliphatic or halogenated aliphatic hydrocarbon group having 1 to 8 carbon atoms or an aromatic hydrocarbon group having 6 to 8 carbon atoms optionally bearing at least one substituent, or a group of the formula:
X C 2 2 2 (IV) wherein X' is fluorine, chlorine, bromine, iodine, or a group of the formula: RlO- or R2COO- as defined above; and Y is fluorine, a group of the formula:
-OR3 (V) wherein R3 is an aliphatic or halogenated aliphatic hydro-carbon group having 1 to 8 carbon atoms except a perfluoro-hydrocarbon group, or an aromatic hydrocarbon group having 6 to 8 carbon atoms optionally bearing at least one substituent, or a group of the formula:
--OCH2Rf (V ' ) wherein Rf is an aliphatic perfluorohydrocarbon having 1 to 7 carbon atomsO
Specific examples of the aliphatic or halogenated aliphatic hydrocarbon or perfluorohydrocarbon group are methyl, ethyl, propyl, trifluoromethyl, 2,2,3,3,3-penta-fluoropropyl, perfluoropropyl,perfluoro (2-propoxy-2-methyl-ethyl), etc. Specific examples of the aromatic hydrocarbon group are phenyl, toluyl, trifluoromethylphenyl, chloro-phenyl, bromophenyl , etc.
The derivative (I) wherein Y is fluorine may beprepared by reacting tetrafluorooxetane with a material by which X is introduced in the derivalive (eg. alkali meta;
halides).
The derivative (I) wherein Y is the group of the formula: -OR3 or -OC~2Rf may be prepared by reacting 'etrafluorooxet~ne with an alcohcl or phenol o~ the formula:
R30H or RfCH20H (VI) wherein R3 and Rf are the same as definea above,in the presence of the material by whioh X is introduced in the derivative.
Specific examples of the alkali r.~tal halides are sodium bromide, potassiun: iodide, potassium ~rGmide, and potassium chloride. The group (II) may be introducea by a mixture of a corresponding alcohol of the lormula:
R1OH (VI) wherein Rl is the same as defined above,and Zll alkali metal halide or an alcoholate of the alcGhol (VI). The group (III) may be introduced by alkali metal salts (eg. sodium or potassium salt) of a corresponding acid. 1'he group (IV) is preferably introduced by a compound o the formula:
FCH2CF2COF or XCH2CF2COF
wherein X is the same as defined in the above.
The above reactlon may be carried out in a sol-vent, specific exa~.ples of which are the abGve-described aprotic solvents, ethers and benzene.
The reaction temperature is usually fro~ 0C to the re~lu~Ling temperature o the solven~ and preera~1y not higher than the temperature to which the reaction mixture is heated by the reaction heat.
The novel 2,2-difluoropropionic acid derivatives of the invention are useful as solven~s, catalysts, monomers, etc.
The present invention will be explained in further detail by the following Examples.
Æxample 1 Diglyme (15 ml), potassium 1uoride (1.8 g) and tetrafluorooxetane (13 g, 0~10 mole) were charged to a 100 ml stainless steel autoclave and stirred at 150C for 8 hours.
A mixture of products (12.8 g) and the unreacted raw material were recovered by distlllation. The product mixture was analyzed by GLC, IR, MS and NMR and found to contain 65% by mole of 2,2,3-trifluoropropionyl fluoride.
Example 2 Activated carbon pellets each having a diameter of `!' 4 mm and a length of 6 mm were immersed in an aqueous solution of potassium fluoride and dried to produce a potassium fluoride catalyst supported on activated carbon in an amount , of 30% by weight based on the weight of the carbon.
The thus produced catalyst pellets (50 ml) were ~ placed in a 3/4 inch Hastelloy-C tube and the interior ^, temperature was kep~ at 380~C. Tetrafluorooxetane (30 g) carried by nitrogen was then passed through the reactor for a period of 30 minutes. The exit gas was trapped in a trap cooled by dry ice. The trapped material (29.5 g) contained, according to GLC analysis, 99.3~ by mole o ~ 'rrade Mark 2,2,3-trifluoropropionyl Eluoride and a trace amount of the unreacted raw material.
Example 3 Carbon tetrachloride (100 ml) and aluminum chloride (5.0 g) were charged to a 300 ml flask equipped with a dry ice condenser and a dropping funnel and stirred. Tetrafluorooxetane (150 ml) was then added in a dropwise manner and stirred for about 2 hours. After cooling, the reaction mixture was rectified to give 2,2,3-triEluoropropionyl fluoride (125 g).
Example 4 SbF5 (5.0 g) was added to a 50 ml flask equipped with a dry ice condenser and a dropping funnel and then tetra-fluorooxetane (30.0 g) was added dropwise with stirring. After the termination of reflux, the reaction mixture was rectified to give 2,2,3-trifluoropropionyl fluoride (23.5 g).
E mple 5 Sodium bromide (aO g, 0.39 mole) and diglyme ~100 ml) which was dehyd~ated by means of a molecular sieve were charged to a 300 ml three-necked flas~. After a condenser was attached to the top of the flask, tetrafluorooxetane (30 ml, 0.32 mole), which had been dehydrated by means of a molecular sieve, was added dropwise over about 30 minutes with stirring on an ice bath. After the addition, the reaction was continued at a room temperature for about 2 and a half hours. The consumption of the tetrafluorooxetane was confirmed by GC.
The reaction mixture was distilled under atmospheric pressure to yield BrCH2CF2COF (42 g). B.P. 73C. Yield, 6?~.
The resul~s of IR and ~S were as ~ollows:
IR: 3,000 cm (C-H, stretching), 1,890 cm (C=O, stretching), 1,430 cm 1, 1,330 cm 1, 1,230 cm 1, 1,140 cm 1, 1,100 cm 1 and 1,040 cm 1, MS: m/e = 192 (M+2, 8.9~), 190 (M, 9.6~), 125 (21~), 123 (21~), 83 (44%), 64 (100~) and 47 (54~).
Example 6 A 28 wt. % solution of sodium methylate in methanol was charged to a 300 ml three-necked flask and then tetra-fluorooxetane (30 ml) was added dropwise on an ice bath. Since the tetrafluorooxetane reacted vigorously as it was added, it was added very gradually over about 1 hour. An ice cooled condenser was attached to the top of the flask.
After the addition, the reaction was continued at room temperature for anothér hour. Termination of the reaction was confirmed by the disappearance of the tetrafluorooxetane peak in GC.
After removing the methanol from the reaction mixture, the residue was poured into water (200 ml) and extracted with ether (300 m~).
After distilling off the ether from the extract under atmospheric pressure, the residue was distilled under a reduced pressure to give CH3OCH2CF2COOCH3 (23.4 g) at 58-9C/40 mmHg.
Yield, 47.5%.
IR: 3,600 cm (C-H), 1,790 cm (C=O), 1,450 cm 25 1,350-1,050 cm 1 (broad), 950 cm 1 and 840 cm 1, MS: m/e = 155 (M+l, 0.4~), 134 (4.9%), 45 (100%), 29 (25~) and 15 (31%).
131~327 g Example 7 Sodium hydride (7.68 g, 0O32 mole) and monoglyme (100 ml) were charged to a three-necked flask. The flask was equipped with a condenser and cooled by ice.
2,2,3,3,3--Pentafluoropropanol (48 g, 0.32 mole) was then added in a dropwise manner. During the addition, hydrogen was vigorously generated. Af-ter termination of the hydrogen generationr tetrafluorooxetane (15 ml, 0.16 mole) was added dropwise over about 30 minutes. Therea~ter, the solution became so viscous that it was difficult to stir it. The solution was poured into water (300 ml) and the lower organic layer was recovered. After distilling off the monoglyme under atmospheric pressure, organic layer was distilled under reduced pressure to give CF3CF2CH2OCH2CF2COOCH2CF2cF3 (35.2 g) at 15 66-68C/ll mmHg. Yield, 28%.
IR: 3,000 cm (C-H), 1,800 cm 1 (C=O), 1,450 cm~
and 1,400-950 cm (broad).
F-NMR (ppm): 7.6 (d, 6F), 36.6 (t, 2F) and 47.1 (s, 4F).
H-NMR: ~(ppm) = 4.8 (t, 2H), 4.12 (t, 2H) ) overlapping 4.1 (t, 2H).
Example 8 A solution of phenol in monoglyme was added dropwise with stirring to a suspension of sodium hydride (2.17 g, 0.057 mole) in monoglyme (10 ml) cooled on an ice bath. After terrnination of the hydrogen generation, tetrafluorooxetane i (2.6 g, 0.02 mole) was added dropwise. Thereafter, the -temperature of the bath was raised to 50C and the reaction was continued at this temperature for about 4 hours. In the course of the reaction, when the mixture became too viscous, it was diluted with monoglyme. Terminatlon of the reaction was confirmed by the disappearance of the tetrafluorooxetane peak in GC.
In TLC (developer, benzene:ethyl acetate = 10:1), a spot of the product was found at Rf = 0.9 (spot for phenol at Rf = 0.8).
The reaction mixture was poured into water, and the lower organic layer was recovered and washed three times with 5 times its volume of water. From the organic layer, ~OCH2CF2COO~
was obtained.
IR: 3,100 cm (aromatlc C-H), 2,950 cm (C-H), 1,780 cm 1 (C=O), 1,590 cm 1, 1,460 cm 1, 1,400-1,000 cm 1 (broad), 950 cm 1, 920 cm 1, 830 cm 1 and 750 cm 1 H-NM~ (in CDC13): ~(ppm) = 4.46 (t, 2H) and 7.2 (m, lOH).
Example 9 Tetrafluorooxetane (650 g, 5 moles) was added drop-wise with stirring to a mixture of sodium iodide (825 g, 5.5 moles) and tetraglyme (1.5 1). After the addition, the reaction mixture was stirred for about 2 hours and then distilled under reduced pressure to give 2~2-difluoro-3-iodopropionyl fluoride (1,128 g). B.P. 35C/95 mmHg.
Yield, 94~.
131~327 MS: m/e = 238 (M , 100%), 191 ~33%), 127 (30~) and 64 (50%)-Example 10 Tetrafluorooxetane (90 ml, 1 mole) was added dropwise5 with stirring to a mixture of potassium iodide (83g, 0.5 mole) ; and tetraglyme (10 ml). After the additlon, the reaction mixture was stirred overnight and then kept standing for several days. Thereafter, the supernatant was recovered by decantation and distilled under reduced pressure to give ICH2CF2COF (60 ml, 107 g) at about 35C/95 mmHg and ICH2CF2CF2CH2CF2COF (20 ml, 32 g) at 91-96C/l9 mmHg.
MS: m/e = 368 (M , 100%), 271 (7%), 241 (35~, 191 (42%), 111 (69%), 95 (38~), 83 (88%) and 64 (46~).
F-N~R (in tetraglyme) (ppm): -93.4 (br, COF), 11.0 (s, CF2O), 32.2 (tt, CF2CO) and 35.9 (q, CH2CF2CF2).
Example 11 Tetrafluorooxetane (10 ml , 0.11 mole) was added dropwise with stirring to a mixture of potassium bromide (6.6 g, 0.055 mole) and tetraglyme (20 ml). After the addition, the reaction mixture was stirred for about 4 hours and then kept standing overnight. The reaction mixture did not separate but was diluted with tetraglyme and analyzed to give following results:
19F-NMR (in tetraglyme) (ppm):
BrCH2CF2COF: -92 (br, COF) and 25.2 (t, CF2).
~rCH2CF2CF2OCH2CF2COF: -91.2 (br, COF~, L0.7 (s, CE'2O), 33.6 (t, CF2CO) and 36.4 (tt, CH2CF2CF2).
Example 12 Tetrafluorooxetane (4 ml, 0.044 mole) was added dropwise wlth stirring to a mixture of potassium chloride (5 g, 0.066 mole), -tetrabutylammonium hydrogensulfate (0.1 g) and diglyme (20 ml). After the addition~ the reaction mixture was stirred for 3 hours and then kept standing overnight. A
part of the supernatant was analyzed by L9F-NMR and the remaining part was distilled under reduced pressure. The products having low boiling temperatures were trapped by a trap cooled with liquid oxygen and analyzed by GC-MS.
19F-NMR (in diglyme) (ppm):
ClCH2CF2COF: -97.9 (br, COF) and 30.2 (t, CF2).
ClcH2cF2cF2ocH2cF2coF: -97.9 (br, COF), 11-2 (s, CF2O), 35.6 (t, CF2CO) and 42.1 (tt, CH2CF2CF2)-Example 13 A mixture of trifluoroacetic acid (12.5 g, 0.110 mole) and glyme (10 ml) was added dropwise to a mixture of glyme (10 ml) and sodium hydride (4.33 g, 0.118 mole) which was washed with a small amount of dry glyme three times. After the addition of the latter mixture and the termination of hydrogen generation, tetrafluorooxetane (9.6 ml, 0.106 mole) was added dropwise. Thereafter, the reaction mixture was stirred over-night and then kept standing ~or a while. A part of the super-natant was analyzed by 19F-N~R and GC~MS and the remainin~
part was distilled under reduced pressure. Volatile materials were trapped with a trap cooled by a dry ice-methanol bath.
The trapped ma-terials were fractioned under atmospheric 1 3 1 ~327 pressure and separated into those distilled at 75C or lower, those distilled at 80C or higher and the hold-up (the bath having a temperature of about 100C). The compounds CF3COOCH2CF2COF and CF3COOCH2 2 2 2 2 be concentrated in the hold-up.
IR: 1,900 cm 1 and 1,880 cm 1 t-COF), and 1,820 cm 1 (--COO--) .
MS: m/e = 205 (M -F, 0.3%), 185 (0.5~), 177 (18%), 127 (46%), 111 (100%), 99 (4~%), 83 (95%), and 69 (92%).
F-NMR (ppm): -96.8 (t, COF), -2.0 (s, CF3) and 35.8 from TFA (td, CF2).
CF3coocH2cF2cF2ocH2cF2coF
MS: m/e = 313 (M -F, 0.2%), 285 (2.5~), 219 (11%), 205 (7%), 177 (68%), 127 (9%), 111 (82%), 83 (95%), 69 (100%) and 64 (61%).
9F-NMR (ppm): -96.8 (s, COF), -1.1 (s, CF3), 2.3 (s, CF2O), 36.4 (t, CF2CO) and 42.0 from TFA (~, CH2CF2CF2)-Example 14 Tetraglyme (200 mlj, cesium fluoride (5.0 g, 0.03 mole) and hexafluoropropyleneoxide dimer (100 g, 0.30 mole) were charged to a 500 ml flask. Tetrafluorooxetane ~50.0 g, 0.38 mole) was added dropwise to the mixture on a ba-th kept at 20C- Thereafter, the reaction mixture was stirred for 5 hours and distilled under atmospheric pressure to give C3F7OCF(CF3)CF2OCH2CF2coF (53 g) at 140C. d = 1.67 (25C).
Elemental analysis: C H F
Calc'd: 23.6%0~4% 65.9%
Found: 23.4~0.44 65.8~
. , ':
';, ',~'
The present inventlon relates to Z,2-diflu~ro-propionic acid derivatives. More particul~rly, it relates to 2,2-difluoropropionic acid derivatives and a process for preparing t~e same from 2~2~3~3-tetrafluorooxetane (herein-after re~erred to as "tetrafluorooxetane").
2,2,3-Trifluoropropionyl fluoride is useful as an intermediate for the production of medic,nes and agricultu-ral chemicals and as a strong acid catalyst. Further, its ester derivative is useful as a solvent, and its dehydrogenated fluorinated derivative is useful as a monomer.
It is known that it can be obtained as one of many products prepared by fluorinating propionyl chloride with fluorine in the presence of a cobalt fluoride catalyst (cf. J. C. Tatlow et al, J. of Fluorine Chemistry, 1973(3), 329-30).
One object or the present invention is to provide , 20 a novel process for preparing 2,2,3-trifluoropropion~-l fiuoride.
Another object of the invention is to provide a novel 2,2-difluoropropionic acid derivatives.
Accordlng to the present invention, 2,2,3-tri-fluoropropionyl fluoride is prepared by conducting a ring opening reaction of tetrafluorooxetane in the presence of a catalyst. ,~
- 2 - l 3 ~ 83~7 Tetrafluorooxetane is a known compound and is easily synthesized by reacting tetrafluoroethylene and formaldehyde.
Specific examples of the catalyst to be used in the above reaction are alkali metal fluorides and Lewis acids.
Pre~erred alkali metal fluorides are sodium fluoride, potassium fluoride and cesium iluoride, and preferred Lewis acids are AlC13 and SbF5 The above reaction may be carried out either in a liquid phase or in a gaseous phase.
When the reaction is carried out in the liquid phasej an alkali metal fluoride is dissolved in an aprotic solvent (eg. diglyme, tetraglyme, acetonitrile, etc.), and tetrafluorooxetane is added-thereto.
The reaction temperature is usually from 80C to the boiling point of the solvent, preerably from 80 to 200C. The reaction time depends on the reaction tempera-` ture, the kind and amount of the catalyst, and is preferably from l to 24 hours.
In the liquid phase reaction~ the preferred catalysts are potassium fluoride and cesium fluoride. The amount of the catalys~ is at least a catalytic amount and preferably from l to 50% by mole based on the tetrafluorooxetane.
In the case of the gaseous phase reaction, when an alkali metal fluoride is used as the catalyst, the reaction temperature should not be higher than 500C, and preferably from 200 to 450C. At temperatures higher than 500C, tetra-fluorooxetane is dscomposed. Th~ reac~ion pressure may be .
.~
:
~ 3 ~ 1 3~ 8327 - atmospheric pressure or a pressure higher or lower than atmospheric pressure as long as the reaction system is kept in the gaseous state. The space velocity depends on other reaction conditions such as the temperature, pressure, the klnd and amount of the catalyst, and is preferably from 10 to 1,000 hr 1, The raw material may be diluted with an in-active gas such as nitrogen.
In the gaseous phase reaction, the catalyst is generally supported on a carrier (eg. activated carbon, asbestos, nickel oxide, silica gel, a molecular sieve, etc.). Of these, activated carbon is preferred.
When a Lewis acid is used as the catalyst, it may be dissolved in a solvent (eg. CH2C12, CHC13, CC14, etc.).
SbF5 does not necessarily require any solvent. The reaction temperature is usually from room temperature to 50C.
If tetrafluorooxetane is analogously ring opened in the presence of an appropriate coreactant, a novel 2,2-difluoropropionic acid derivative may be prepared.
` The novel 2,2-difluoropropionic acid derivative of the invention can be represented by the formula:
XcH2CF2COY (I) wherein X is chlorine, bromine, iodine, a group of the formula:
lO- (II) 25 or R2COO- (III1 ` .
:
,~
- 4 ~ 1 31 8327 wherein Rl and R2 are each an aliphatic or halogenated aliphatic hydrocarbon group having 1 to 8 carbon atoms or an aromatic hydrocarbon group having 6 to 8 carbon atoms optionally bearing at least one substituent, or a group of the formula:
X C 2 2 2 (IV) wherein X' is fluorine, chlorine, bromine, iodine, or a group of the formula: RlO- or R2COO- as defined above; and Y is fluorine, a group of the formula:
-OR3 (V) wherein R3 is an aliphatic or halogenated aliphatic hydro-carbon group having 1 to 8 carbon atoms except a perfluoro-hydrocarbon group, or an aromatic hydrocarbon group having 6 to 8 carbon atoms optionally bearing at least one substituent, or a group of the formula:
--OCH2Rf (V ' ) wherein Rf is an aliphatic perfluorohydrocarbon having 1 to 7 carbon atomsO
Specific examples of the aliphatic or halogenated aliphatic hydrocarbon or perfluorohydrocarbon group are methyl, ethyl, propyl, trifluoromethyl, 2,2,3,3,3-penta-fluoropropyl, perfluoropropyl,perfluoro (2-propoxy-2-methyl-ethyl), etc. Specific examples of the aromatic hydrocarbon group are phenyl, toluyl, trifluoromethylphenyl, chloro-phenyl, bromophenyl , etc.
The derivative (I) wherein Y is fluorine may beprepared by reacting tetrafluorooxetane with a material by which X is introduced in the derivalive (eg. alkali meta;
halides).
The derivative (I) wherein Y is the group of the formula: -OR3 or -OC~2Rf may be prepared by reacting 'etrafluorooxet~ne with an alcohcl or phenol o~ the formula:
R30H or RfCH20H (VI) wherein R3 and Rf are the same as definea above,in the presence of the material by whioh X is introduced in the derivative.
Specific examples of the alkali r.~tal halides are sodium bromide, potassiun: iodide, potassium ~rGmide, and potassium chloride. The group (II) may be introducea by a mixture of a corresponding alcohol of the lormula:
R1OH (VI) wherein Rl is the same as defined above,and Zll alkali metal halide or an alcoholate of the alcGhol (VI). The group (III) may be introduced by alkali metal salts (eg. sodium or potassium salt) of a corresponding acid. 1'he group (IV) is preferably introduced by a compound o the formula:
FCH2CF2COF or XCH2CF2COF
wherein X is the same as defined in the above.
The above reactlon may be carried out in a sol-vent, specific exa~.ples of which are the abGve-described aprotic solvents, ethers and benzene.
The reaction temperature is usually fro~ 0C to the re~lu~Ling temperature o the solven~ and preera~1y not higher than the temperature to which the reaction mixture is heated by the reaction heat.
The novel 2,2-difluoropropionic acid derivatives of the invention are useful as solven~s, catalysts, monomers, etc.
The present invention will be explained in further detail by the following Examples.
Æxample 1 Diglyme (15 ml), potassium 1uoride (1.8 g) and tetrafluorooxetane (13 g, 0~10 mole) were charged to a 100 ml stainless steel autoclave and stirred at 150C for 8 hours.
A mixture of products (12.8 g) and the unreacted raw material were recovered by distlllation. The product mixture was analyzed by GLC, IR, MS and NMR and found to contain 65% by mole of 2,2,3-trifluoropropionyl fluoride.
Example 2 Activated carbon pellets each having a diameter of `!' 4 mm and a length of 6 mm were immersed in an aqueous solution of potassium fluoride and dried to produce a potassium fluoride catalyst supported on activated carbon in an amount , of 30% by weight based on the weight of the carbon.
The thus produced catalyst pellets (50 ml) were ~ placed in a 3/4 inch Hastelloy-C tube and the interior ^, temperature was kep~ at 380~C. Tetrafluorooxetane (30 g) carried by nitrogen was then passed through the reactor for a period of 30 minutes. The exit gas was trapped in a trap cooled by dry ice. The trapped material (29.5 g) contained, according to GLC analysis, 99.3~ by mole o ~ 'rrade Mark 2,2,3-trifluoropropionyl Eluoride and a trace amount of the unreacted raw material.
Example 3 Carbon tetrachloride (100 ml) and aluminum chloride (5.0 g) were charged to a 300 ml flask equipped with a dry ice condenser and a dropping funnel and stirred. Tetrafluorooxetane (150 ml) was then added in a dropwise manner and stirred for about 2 hours. After cooling, the reaction mixture was rectified to give 2,2,3-triEluoropropionyl fluoride (125 g).
Example 4 SbF5 (5.0 g) was added to a 50 ml flask equipped with a dry ice condenser and a dropping funnel and then tetra-fluorooxetane (30.0 g) was added dropwise with stirring. After the termination of reflux, the reaction mixture was rectified to give 2,2,3-trifluoropropionyl fluoride (23.5 g).
E mple 5 Sodium bromide (aO g, 0.39 mole) and diglyme ~100 ml) which was dehyd~ated by means of a molecular sieve were charged to a 300 ml three-necked flas~. After a condenser was attached to the top of the flask, tetrafluorooxetane (30 ml, 0.32 mole), which had been dehydrated by means of a molecular sieve, was added dropwise over about 30 minutes with stirring on an ice bath. After the addition, the reaction was continued at a room temperature for about 2 and a half hours. The consumption of the tetrafluorooxetane was confirmed by GC.
The reaction mixture was distilled under atmospheric pressure to yield BrCH2CF2COF (42 g). B.P. 73C. Yield, 6?~.
The resul~s of IR and ~S were as ~ollows:
IR: 3,000 cm (C-H, stretching), 1,890 cm (C=O, stretching), 1,430 cm 1, 1,330 cm 1, 1,230 cm 1, 1,140 cm 1, 1,100 cm 1 and 1,040 cm 1, MS: m/e = 192 (M+2, 8.9~), 190 (M, 9.6~), 125 (21~), 123 (21~), 83 (44%), 64 (100~) and 47 (54~).
Example 6 A 28 wt. % solution of sodium methylate in methanol was charged to a 300 ml three-necked flask and then tetra-fluorooxetane (30 ml) was added dropwise on an ice bath. Since the tetrafluorooxetane reacted vigorously as it was added, it was added very gradually over about 1 hour. An ice cooled condenser was attached to the top of the flask.
After the addition, the reaction was continued at room temperature for anothér hour. Termination of the reaction was confirmed by the disappearance of the tetrafluorooxetane peak in GC.
After removing the methanol from the reaction mixture, the residue was poured into water (200 ml) and extracted with ether (300 m~).
After distilling off the ether from the extract under atmospheric pressure, the residue was distilled under a reduced pressure to give CH3OCH2CF2COOCH3 (23.4 g) at 58-9C/40 mmHg.
Yield, 47.5%.
IR: 3,600 cm (C-H), 1,790 cm (C=O), 1,450 cm 25 1,350-1,050 cm 1 (broad), 950 cm 1 and 840 cm 1, MS: m/e = 155 (M+l, 0.4~), 134 (4.9%), 45 (100%), 29 (25~) and 15 (31%).
131~327 g Example 7 Sodium hydride (7.68 g, 0O32 mole) and monoglyme (100 ml) were charged to a three-necked flask. The flask was equipped with a condenser and cooled by ice.
2,2,3,3,3--Pentafluoropropanol (48 g, 0.32 mole) was then added in a dropwise manner. During the addition, hydrogen was vigorously generated. Af-ter termination of the hydrogen generationr tetrafluorooxetane (15 ml, 0.16 mole) was added dropwise over about 30 minutes. Therea~ter, the solution became so viscous that it was difficult to stir it. The solution was poured into water (300 ml) and the lower organic layer was recovered. After distilling off the monoglyme under atmospheric pressure, organic layer was distilled under reduced pressure to give CF3CF2CH2OCH2CF2COOCH2CF2cF3 (35.2 g) at 15 66-68C/ll mmHg. Yield, 28%.
IR: 3,000 cm (C-H), 1,800 cm 1 (C=O), 1,450 cm~
and 1,400-950 cm (broad).
F-NMR (ppm): 7.6 (d, 6F), 36.6 (t, 2F) and 47.1 (s, 4F).
H-NMR: ~(ppm) = 4.8 (t, 2H), 4.12 (t, 2H) ) overlapping 4.1 (t, 2H).
Example 8 A solution of phenol in monoglyme was added dropwise with stirring to a suspension of sodium hydride (2.17 g, 0.057 mole) in monoglyme (10 ml) cooled on an ice bath. After terrnination of the hydrogen generation, tetrafluorooxetane i (2.6 g, 0.02 mole) was added dropwise. Thereafter, the -temperature of the bath was raised to 50C and the reaction was continued at this temperature for about 4 hours. In the course of the reaction, when the mixture became too viscous, it was diluted with monoglyme. Terminatlon of the reaction was confirmed by the disappearance of the tetrafluorooxetane peak in GC.
In TLC (developer, benzene:ethyl acetate = 10:1), a spot of the product was found at Rf = 0.9 (spot for phenol at Rf = 0.8).
The reaction mixture was poured into water, and the lower organic layer was recovered and washed three times with 5 times its volume of water. From the organic layer, ~OCH2CF2COO~
was obtained.
IR: 3,100 cm (aromatlc C-H), 2,950 cm (C-H), 1,780 cm 1 (C=O), 1,590 cm 1, 1,460 cm 1, 1,400-1,000 cm 1 (broad), 950 cm 1, 920 cm 1, 830 cm 1 and 750 cm 1 H-NM~ (in CDC13): ~(ppm) = 4.46 (t, 2H) and 7.2 (m, lOH).
Example 9 Tetrafluorooxetane (650 g, 5 moles) was added drop-wise with stirring to a mixture of sodium iodide (825 g, 5.5 moles) and tetraglyme (1.5 1). After the addition, the reaction mixture was stirred for about 2 hours and then distilled under reduced pressure to give 2~2-difluoro-3-iodopropionyl fluoride (1,128 g). B.P. 35C/95 mmHg.
Yield, 94~.
131~327 MS: m/e = 238 (M , 100%), 191 ~33%), 127 (30~) and 64 (50%)-Example 10 Tetrafluorooxetane (90 ml, 1 mole) was added dropwise5 with stirring to a mixture of potassium iodide (83g, 0.5 mole) ; and tetraglyme (10 ml). After the additlon, the reaction mixture was stirred overnight and then kept standing for several days. Thereafter, the supernatant was recovered by decantation and distilled under reduced pressure to give ICH2CF2COF (60 ml, 107 g) at about 35C/95 mmHg and ICH2CF2CF2CH2CF2COF (20 ml, 32 g) at 91-96C/l9 mmHg.
MS: m/e = 368 (M , 100%), 271 (7%), 241 (35~, 191 (42%), 111 (69%), 95 (38~), 83 (88%) and 64 (46~).
F-N~R (in tetraglyme) (ppm): -93.4 (br, COF), 11.0 (s, CF2O), 32.2 (tt, CF2CO) and 35.9 (q, CH2CF2CF2).
Example 11 Tetrafluorooxetane (10 ml , 0.11 mole) was added dropwise with stirring to a mixture of potassium bromide (6.6 g, 0.055 mole) and tetraglyme (20 ml). After the addition, the reaction mixture was stirred for about 4 hours and then kept standing overnight. The reaction mixture did not separate but was diluted with tetraglyme and analyzed to give following results:
19F-NMR (in tetraglyme) (ppm):
BrCH2CF2COF: -92 (br, COF) and 25.2 (t, CF2).
~rCH2CF2CF2OCH2CF2COF: -91.2 (br, COF~, L0.7 (s, CE'2O), 33.6 (t, CF2CO) and 36.4 (tt, CH2CF2CF2).
Example 12 Tetrafluorooxetane (4 ml, 0.044 mole) was added dropwise wlth stirring to a mixture of potassium chloride (5 g, 0.066 mole), -tetrabutylammonium hydrogensulfate (0.1 g) and diglyme (20 ml). After the addition~ the reaction mixture was stirred for 3 hours and then kept standing overnight. A
part of the supernatant was analyzed by L9F-NMR and the remaining part was distilled under reduced pressure. The products having low boiling temperatures were trapped by a trap cooled with liquid oxygen and analyzed by GC-MS.
19F-NMR (in diglyme) (ppm):
ClCH2CF2COF: -97.9 (br, COF) and 30.2 (t, CF2).
ClcH2cF2cF2ocH2cF2coF: -97.9 (br, COF), 11-2 (s, CF2O), 35.6 (t, CF2CO) and 42.1 (tt, CH2CF2CF2)-Example 13 A mixture of trifluoroacetic acid (12.5 g, 0.110 mole) and glyme (10 ml) was added dropwise to a mixture of glyme (10 ml) and sodium hydride (4.33 g, 0.118 mole) which was washed with a small amount of dry glyme three times. After the addition of the latter mixture and the termination of hydrogen generation, tetrafluorooxetane (9.6 ml, 0.106 mole) was added dropwise. Thereafter, the reaction mixture was stirred over-night and then kept standing ~or a while. A part of the super-natant was analyzed by 19F-N~R and GC~MS and the remainin~
part was distilled under reduced pressure. Volatile materials were trapped with a trap cooled by a dry ice-methanol bath.
The trapped ma-terials were fractioned under atmospheric 1 3 1 ~327 pressure and separated into those distilled at 75C or lower, those distilled at 80C or higher and the hold-up (the bath having a temperature of about 100C). The compounds CF3COOCH2CF2COF and CF3COOCH2 2 2 2 2 be concentrated in the hold-up.
IR: 1,900 cm 1 and 1,880 cm 1 t-COF), and 1,820 cm 1 (--COO--) .
MS: m/e = 205 (M -F, 0.3%), 185 (0.5~), 177 (18%), 127 (46%), 111 (100%), 99 (4~%), 83 (95%), and 69 (92%).
F-NMR (ppm): -96.8 (t, COF), -2.0 (s, CF3) and 35.8 from TFA (td, CF2).
CF3coocH2cF2cF2ocH2cF2coF
MS: m/e = 313 (M -F, 0.2%), 285 (2.5~), 219 (11%), 205 (7%), 177 (68%), 127 (9%), 111 (82%), 83 (95%), 69 (100%) and 64 (61%).
9F-NMR (ppm): -96.8 (s, COF), -1.1 (s, CF3), 2.3 (s, CF2O), 36.4 (t, CF2CO) and 42.0 from TFA (~, CH2CF2CF2)-Example 14 Tetraglyme (200 mlj, cesium fluoride (5.0 g, 0.03 mole) and hexafluoropropyleneoxide dimer (100 g, 0.30 mole) were charged to a 500 ml flask. Tetrafluorooxetane ~50.0 g, 0.38 mole) was added dropwise to the mixture on a ba-th kept at 20C- Thereafter, the reaction mixture was stirred for 5 hours and distilled under atmospheric pressure to give C3F7OCF(CF3)CF2OCH2CF2coF (53 g) at 140C. d = 1.67 (25C).
Elemental analysis: C H F
Calc'd: 23.6%0~4% 65.9%
Found: 23.4~0.44 65.8~
. , ':
';, ',~'
Claims
Claims:
1. A 2,2-difluoropropionic acid derivative of the formula:
XCH2CF2COY (I) wherein X is chlorine, bromine, iodine, a group of the formula:
R1O- (II) or R2COO- (III) wherein R1 and R2 are each an aliphatic or halogenated aliphatic hydrocarbon group having 1 to 8 carbon atoms or phenyl, tolyl, trifluoromethylphenyl, chlorophenyl or bromophenyl, or a group of the formula:
X'CH2CF2CF2O- (IV) wherein X' is fluorine, chlorine, bromine, iodine, or a group of the formula: R1O- or R2COO- as defined above; and Y is fluorine, a group of the formula:
-OR3 (V) wherein R3 is an aliphatic or halogenated aliphatic hydrocarbon group having 1 to 8 carbon atoms except a perfluorohydrocarbon group, or phenyl, tolyl, trifluoromethylphenyl, chlorophenyl or bromophenyl, or a group of the formula:
-OCH2Rf (V') wherein Rf is an aliphatic perfluorohydrocarbon having 1 to 7 carbon atoms.
2. A derivative according to claim 1, wherein Y is fluorine.
3. A derivative according to claim 1, wherein Y is the group (V) or (V').
4. A derivative according to claim 1, wherein X is selected from the group consisting of chlorine, bromine and iodine.
5. A derivative according to claim 1, wherein X is said group of the formula:
R1O- (II) or R2COO- (III) 6. A derivative according to claim 1, wherein X is said group of the formula:
X'CH2CF2CF2O- (IV) 7. A process for preparing a 2,2-difluoropropionic acid derivative of the formula:
XCH2CF2COY (I) wherein X is chlorine, bromine, iodine, a group of the formula:
R1O- (II) or R2COO- (III) wherein R1 and R2 are each an aliphatic or halogenated aliphatic hydrocarbon group having 1 to 8 carbon atoms or phenyl, tolyl, trifluoromethylphenyl, chlorophenyl or bromophenyl, or a group of the formula:
X'CH2CF2CF2O- (IV) wherein X' is fluorine, chlorine, bromine, iodine, or a group of the formula: R1O- or R2COO- as defined above; and Y is fluorine, a group of the formula:
-OR3 (V) wherein R3 is an aliphatic or halogenated aliphatic hydrocarbon group having 1 to 8 carbon atoms except a perfluorohydrocarbon group, or phenyl, tolyl, trifluoromethylpherlyl, chlorophenyl or bromophenyl, or a group of the formula:
-OCH2Rf (V') wherein Rf is an aliphatic perfluorohydrocarbon having 1 to 7 carbon atoms; which process comprises reacting tetrafluorooxetane with a material by which the group X is introduced into the derivative optionally in the presence of an alcohol or a phenol of the formula:
R3OH or RfCH2OH
wherein R3 and Rf are as defined above.
1. A 2,2-difluoropropionic acid derivative of the formula:
XCH2CF2COY (I) wherein X is chlorine, bromine, iodine, a group of the formula:
R1O- (II) or R2COO- (III) wherein R1 and R2 are each an aliphatic or halogenated aliphatic hydrocarbon group having 1 to 8 carbon atoms or phenyl, tolyl, trifluoromethylphenyl, chlorophenyl or bromophenyl, or a group of the formula:
X'CH2CF2CF2O- (IV) wherein X' is fluorine, chlorine, bromine, iodine, or a group of the formula: R1O- or R2COO- as defined above; and Y is fluorine, a group of the formula:
-OR3 (V) wherein R3 is an aliphatic or halogenated aliphatic hydrocarbon group having 1 to 8 carbon atoms except a perfluorohydrocarbon group, or phenyl, tolyl, trifluoromethylphenyl, chlorophenyl or bromophenyl, or a group of the formula:
-OCH2Rf (V') wherein Rf is an aliphatic perfluorohydrocarbon having 1 to 7 carbon atoms.
2. A derivative according to claim 1, wherein Y is fluorine.
3. A derivative according to claim 1, wherein Y is the group (V) or (V').
4. A derivative according to claim 1, wherein X is selected from the group consisting of chlorine, bromine and iodine.
5. A derivative according to claim 1, wherein X is said group of the formula:
R1O- (II) or R2COO- (III) 6. A derivative according to claim 1, wherein X is said group of the formula:
X'CH2CF2CF2O- (IV) 7. A process for preparing a 2,2-difluoropropionic acid derivative of the formula:
XCH2CF2COY (I) wherein X is chlorine, bromine, iodine, a group of the formula:
R1O- (II) or R2COO- (III) wherein R1 and R2 are each an aliphatic or halogenated aliphatic hydrocarbon group having 1 to 8 carbon atoms or phenyl, tolyl, trifluoromethylphenyl, chlorophenyl or bromophenyl, or a group of the formula:
X'CH2CF2CF2O- (IV) wherein X' is fluorine, chlorine, bromine, iodine, or a group of the formula: R1O- or R2COO- as defined above; and Y is fluorine, a group of the formula:
-OR3 (V) wherein R3 is an aliphatic or halogenated aliphatic hydrocarbon group having 1 to 8 carbon atoms except a perfluorohydrocarbon group, or phenyl, tolyl, trifluoromethylpherlyl, chlorophenyl or bromophenyl, or a group of the formula:
-OCH2Rf (V') wherein Rf is an aliphatic perfluorohydrocarbon having 1 to 7 carbon atoms; which process comprises reacting tetrafluorooxetane with a material by which the group X is introduced into the derivative optionally in the presence of an alcohol or a phenol of the formula:
R3OH or RfCH2OH
wherein R3 and Rf are as defined above.
Applications Claiming Priority (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58251070A JPS60136536A (en) | 1983-12-26 | 1983-12-26 | Production of 2,2,3-trifluoropropinonyl fluoride |
| JP251070/1983 | 1983-12-26 | ||
| JP59253884A JPS61130254A (en) | 1984-11-29 | 1984-11-29 | 2,2-difluoropropionic acid derivative |
| JP253884/1984 | 1984-11-29 | ||
| CA000470916A CA1293739C (en) | 1983-12-26 | 1984-12-21 | Process for preparing 2,2,3-trifluoropropionyl fluoride |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000470916A Division CA1293739C (en) | 1983-12-26 | 1984-12-21 | Process for preparing 2,2,3-trifluoropropionyl fluoride |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1318327C true CA1318327C (en) | 1993-05-25 |
Family
ID=27167488
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000616011A Expired - Fee Related CA1318327C (en) | 1983-12-26 | 1991-02-27 | 2,2-difluoropropionic acid derivatives |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1318327C (en) |
-
1991
- 1991-02-27 CA CA000616011A patent/CA1318327C/en not_active Expired - Fee Related
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