JPH10251172A - Production of 1,1,1,3,3-pentafluoropropane - Google Patents

Abstract

PROBLEM TO BE SOLVED: To readily obtain the subject compound that can be used as an alternative of chlorofluorocarbon or hydrochlorofluorocarbon as a refrigerant or a foaming agent from an inexpensively available trihalomethane and vinylidene fluoride. SOLUTION: The addition reaction of (A) a trihalomethane of the formula: CH(X<1> )(X<2> )(X<3> ) (X<1> -X<3> are each a halogen and there is no case that all of them are not F atom) to (B) vinylidene fluoride is carried out, preferably radically to prepare (C) 1,1,1-trihalogeno-3,3-difluoropropane and the product is fluorinated using a metal fluoride salt and/or hydrogen fluoride as a fluorinating agent to give the objective 1,1,1,3,3-pentafluoropropane. Thus, the objective compound is easily, efficiently and site-selectively produced under relatively mild conditions.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a useful compound which can be used as a substitute for CFC (chlorofluorocarbon) or HCFC (hydrochlorofluorocarbon) used as a refrigerant, a blowing agent and a cleaning agent. ,
3,3-pentafluoropropane (HFC-245f
It relates to the production method of a).

[0002]

2. Description of the Related Art As a method for synthesizing 1,1,1,3,3-pentafluoropropane, a method for synthesizing 1,1,1,3
Fluorination using hydrogen fluoride (HF) in the presence of a fluorination catalyst for 3,3-pentachloropropane is known.

[0003] In this method, however, the reaction is generally carried out using pentavalent antimony as a catalyst, but in order to keep the selectivity high and to increase the productivity, an HF solvent (that is, in the liquid phase) is used. It is necessary to carry out the reaction, the material of the reactor that can be used under these reaction conditions is limited, and generally expensive materials are required.

Further, 1,1,1,3,3-pentafluoro- obtained by fluorination of hexachloropropene is used.
A synthesis method by reduction of 2,3-dichloropropane is also known, but this method requires a two-step reaction of raw material synthesis and reduction, and the process is complicated.

The fluorination of 1,1,1,3,3-pentahalogenopropane (eg, 1,1,1,3,3-pentachloropropane) having a chlorine atom at the 3-position is In particular, the reactivity of the chlorine atom at the 3-position is low, and in many cases, a large amount of by-products are generated, and the productivity in this process is low.

Further, a method of synthesizing 1,1,1,3,3-pentafluoropropane by hydrogenating 1,1,1,3,3-pentafluoropropene is also known.
In this method, it is difficult to obtain 1,1,1,3,3-pentafluoropropene, which is a raw material, and it is difficult to carry out the method industrially.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to produce 1,1,1,3,3-pentafluoropropane efficiently and economically from inexpensive raw materials.

[0008]

The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, can easily obtain 1,1,1-trihalogeno-3 from trihalomethane and vinylidene fluoride which are available at low cost. , 3-difluoropropane, and further, by fluorinating the 1,1,1-trihalogeno-3,3-difluoropropane, useful 1,1, which can be an alternative compound such as CFC or HCFC. It has been found that 1,3,3-pentafluoropropane can be efficiently produced.

That is, the present invention provides a compound represented by the general formula: CH (X¹) (X^Two) (X^Three)  (However, X¹, X^Two, X^ThreeAre different or the same
Is a halogen atom and all are fluorine atoms
Absent. ) And vinylidene fluoride
1,1,1-trihalo obtained by addition reaction with
Fluorinating geno-3,3-difluoropropane,
How to make 1,1,1,3,3-pentafluoropropane
(Hereinafter referred to as the production method of the present invention).
is there.

According to the production method of the present invention, addition of trihalomethane (CH (X ¹ ) (X ² ) (X ³ ): for example, chloroform or fluorodichloromethane) and vinylidene fluoride (CF ₂ CH ₂ ) Reaction (particularly radical reaction)
Thus, 1,1,1-trihalogeno-3,3-difluoropropane (CH) having no chlorine atom at the 3-position
(X ¹ ) (X ² ) (X ³ ) CH ₂ CHF ₂ ) can be obtained easily and regioselectively efficiently from raw materials that can be obtained at low cost. In this 1,1,1-trihalogeno-3,3-difluoropropane, the halogen atom at the 3-position is a fluorine atom, so that the halogen atom at the 1-position (X ¹ , X ² ,
X ³ ) is easily and regioselectively efficiently fluorinated by a fluorinating agent, and can be a substitute compound such as CFC or HCFC useful as a refrigerant, a blowing agent, a cleaning agent, and the like.
1,1,3,3-pentafluoropropane (CF ₃ CH
₂ CHF ₂ : HFC245fa) can be produced efficiently (ie, with good productivity) and economically under relatively mild conditions.

Next, the reaction process in the production method of the present invention will be described.

When the above-mentioned trihalomethane (eg, chloroform) is heated in the presence of a reaction initiator (eg, benzoyl peroxide) for an addition reaction (particularly, a radical reaction), its hydrogen atom is abstracted and eliminated, resulting in trihalomethyl. Radicals (· C (X ¹ ) (X ² ) (X ³ )) are generated.

The generated trihalomethyl radical is added to the “= CH ₂ ” position of vinylidene fluoride when vinylidene fluoride (CF ₂ ＣＨCH ₂ ) is simultaneously present, and as a result, 1,1,1-trihalogeno- 3,3-difluoropropane is relatively mild (for example, a reaction temperature of 90 ° C.,
(Reaction time: about 5 hours).

The 1,1,1-trihalogeno-3,3-
The reaction for producing difluoropropane can be represented by the following scheme (I).

Embedded image

In the scheme (I), first, as shown in a reaction formula (a), a hydrogen atom is extracted by heating a trihalomethane in the presence of a reaction initiator (radical reaction initiator). A trihalomethyl radical is generated.

Next, as shown in the reaction formula (b), in the presence of vinylidene fluoride, the trihalomethyl radical is regioselectively added to the “＝ CH ₂ ” position of vinylidene fluoride. A radical represented by the formula (D) is generated.

This is because, as shown in the following formula A, polarization occurs in the vinylidene fluoride molecule due to the large electronegativity of the fluorine atom, and "= CF ₂ "
The polarity of the carbon atom at the position is relatively large relative to the polarity of the carbon atom at the position of “= CH ₂ ”, so that the trihalomethyl radical is regioselectively located at the position of “= CH ₂ ” of the vinylidene fluoride molecule It is considered that a radical represented by the structural formula (D) is generated by addition. In addition, the regioselectivity is such that a hydrogen atom has a relatively small size as compared with a fluorine atom, and “= CH ₂ ” as compared with a carbon atom at the “= CF ₂ ” position.
It is also conceivable that this is due to the fact that it is easily bonded to the carbon atom at the position.

[0018]

Embedded image

Next, as shown in the reaction formula (c), 1,1,1-trihalogeno-3,3-difluoropropane is generated by the reaction of the radical represented by the structural formula (D) with trihalomethane. .

Generally, in the polymerization reaction of ethylene compounds such as vinyl chloride (particularly, radical polymerization reaction),
This polymerization reaction proceeds in a chain to produce a polymer having a high degree of polymerization. It is known that when a polymer having a small degree of polymerization or an adduct is obtained, a polymerization inhibitor capable of suppressing the progress of the polymerization reaction is appropriately added.

According to the production method of the present invention, the series of reactions represented by the above-mentioned scheme (I) can be carried out without using a polymerization inhibitor, without using an inhibitor of trihalomethane and vinylidene fluoride. 1,1-Trihalogeno-3,3-difluoropropane can be obtained as the main product. Also,
Even when the above polymerization reaction proceeds, the obtained by-product is a bimolecular polymer or trimolecular polymer of vinylidene fluoride. Further, as described above, the progress of the polymerization reaction is suppressed, and
In order to obtain 1,1-trihalogeno-3,3-difluoropropane efficiently, the molar ratio of the reaction between trihalomethane and vinylidene fluoride is (1: 0.2) to (1: 0.
It is preferable to be about 4).

The 1,1,1-trihalogeno-3,3-difluoropropane thus obtained has no chlorine atom at the 3-position, has a fluorine atom bonded thereto, and has a trihalogeno at the 1-position. Since the reaction activity of the methyl group is high and the reaction rate is high, it is easily fluorinated under relatively mild conditions (for example, a reaction temperature of 80 ° C. and a reaction time of about 3 hours),
1,1,1,3,3-pentafluoropropane is produced with high productivity.

These are 1,1,1-trihalogeno-3,
The electronegativity of the fluorine atom at the 3-position of the 3-difluoropropane molecule is large (a fluorine atom is 4.0, and a chlorine atom is 3.20).
0: Both are based on thermodynamic data by Linus Pauling), and a bias of electric charge occurs in the 3-position in the molecule to increase the electron density of the carbon atom at the 1-position in the molecule (that is, the electron density at the 1-position). It is considered that this is because the bonding force between the carbon atom and the halogen atom is weakened), and the halogen atom (particularly, chlorine atom) bonded at this position is easily eliminated and replaced with a fluorine atom.

This reaction can be represented by the following scheme (II).

[0025]

Embedded image

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION In the production method of the present invention, the addition reaction is considered to be a radical reaction.

As described above, the above trihalomethane (C
H (X ¹ ) (X ² ) (X ³ ): eg chloroform
Is heated in the presence of a radical reaction initiator (for example, benzoyl peroxide or the like) to form a trihalomethyl radical (.C (X ¹ ) together with a hydrogen radical (.H).
(X ² ) (X ³ )), and the generated trihalomethyl radical is simultaneously converted to vinylidene fluoride (CF ₂ ＣC
H ₂ ), the presence of “= C” in vinylidene fluoride
Added in H ₂ "position, this results 1,1,1-trihalogeno-3,3-difluoro-propane is produced.

In the production method of the present invention, the trihalomethane is preferably a compound selected from the group consisting of chloroform (CHCl ₃ ), fluorodichloromethane (CHFCl ₂ ), and difluorochloromethane (CHF ₂ Cl). . These are all industrially easily available and inexpensive compounds.

Further, one of the raw materials, vinylidene fluoride (CF ₂ ＣＨCH ₂ ), can be prepared by a known method. For example, it is easily produced by thermal decomposition of 1,1-difluoro-1-chloroethane (CF ₂ ClCH ₃ ).

As described above, in the production method of the present invention, the obtained 1,1,1-trihalogeno-3,3-difluoropropane is a corresponding compound depending on the type of trihalomethane used as a raw material.

For example, when chloroform is used as trihalomethane as a raw material, 1,1,1-trichloro-
3,3-Difluoropropane is obtained, and when using fluorodichloromethane, 1,1-dichloro-1,
3,3-trifluoropropane is obtained, and when difluorochloromethane is used, 1-chloro-1,1,1
3,3-Tetrafluoropropane is obtained.

In the production method of the present invention, an organic carboxylic acid peroxide can be used as a reaction initiator for the radical reaction.

As the reaction initiator, generally used radical reaction initiators (radical polymerization initiators) can be used, and the type thereof is not particularly limited, but benzoyl peroxide (benzoyl peroxide) or lauroyl peroxide can be used. It is preferable to use an organic carboxylic acid peroxide such as an oxide (lauroyl peroxide).

In the production method of the present invention, 1,1,1-trihalogeno-3,3-difluoropropane (CH (X ¹ ) (X ² ) (X ³ ) CH ₂ obtained as described above.
CHF ₂ : However, X ^{1 to} X ³ are the same as those described above.
Is fluorinated by the reaction described above.

However, as described above, the 1,1,1-trihalogeno-3,3-
Since there is no chlorine atom at the 3-position in the difluoropropane molecule and the reaction activity of the trihalogenomethyl group at the 1-position is high, for example, 1,1,1,3,3-pentafluoro-2,3- The reaction rate is higher than when using a starting material in a conventional fluorination reaction in which a chlorine atom is present at the 3-position, such as dichloropropane,
In addition to improving productivity, it has features such as that the reaction proceeds under mild conditions, and also improves selectivity and yield in this fluorination reaction.

In the production method of the present invention, a fluorinating agent or a fluorination catalyst for the above-mentioned fluorination reaction and other known fluorination conditions may be employed.

For example, hydrogen fluoride, a metal fluoride salt (for example, antimony trifluoride) or the like is used as a fluorinating agent, and a metal halide salt (for example, Fluorination can be performed using a metal fluoride salt such as antimony fluoride).

In particular, the above-mentioned metal halide salts include:
SbF _n Cl _5-n (n = 0 to 5) or SbF _n Cl
It is preferable to use pentavalent or trivalent antimony chloride represented by _3-n (n = 0 to 3). Among them,
Antimony pentafluoride (SbF ₅ ) having a high fluorine content is particularly preferred.

In this reaction, the 1-position trihalogenomethyl group (for example, trichloromethyl group or fluorodichloromethyl group) of 1,1,1-trihalogeno-3,3-difluoropropane has high reaction activity. Therefore, the reaction rate is higher than that of a fluorination reaction of a compound containing a chlorine atom at the 3-position such as 1,1,1,3,3-pentachloropropane, and the productivity per reaction vessel is improved. Can be done. The conditions such as temperature and time for this reaction are relatively mild as exemplified above.

When fluorinating the above-mentioned compound containing a chlorine atom at the 3-position, it is necessary to carry out the reaction in hydrogen fluoride in order to increase the selectivity (selectivity) of the reaction.
Based on the present invention, the above 1,1,1-trihalogeno-
When fluorinating 3,3-difluoropropane, antimony fluorinated chloride having an appropriate fluorine content (or
SbF ₅ , SbF _{3, and the} like: Hereinafter, they may be referred to as all-antimony fluoride. ), The desired 1,1,1,3,3-pentafluoropropane can be obtained with high selectivity.

When the fluorination reaction is carried out using antimony fluoride or antimony fluoride as described above, the corrosiveness is reduced to such an extent that an inexpensive material can be used as a reaction vessel. This is advantageous.

In the production method of the present invention, in a liquid phase reaction using a metal halide salt (particularly, antimony fluoride such as antimony chloride or perfluorinated antimony), the fluorination reaction is carried out at a reaction temperature of 40 ° C. It is sufficiently possible to carry out the reaction at １００100 ° C. and a reaction pressure of 2-20 kg / cm ² .

Unless the temperature is 100 ° C. or more and the reaction pressure is 20 kg / cm ² or more, the yield, selectivity, conversion and the like of the target product may be deteriorated. On the other hand, in the production method of the present invention, 1,1,1-trihalogeno which is a starting material for the fluorination reaction is used.
Since there is no chlorine atom at the 3-position of 3,3-difluoropropane and the trihalogenomethyl group (1st-position) has high reaction activity, it is relatively mild as shown in the above reaction temperature and reaction pressure. The target is 1,1,1,
It is possible to produce 3,3-pentafluoropropane with good selectivity. In the fluorination reaction using a metal halide salt (especially antimony halide), the temperature is more preferably 60 ° C. to 80 ° C. and the reaction pressure is more preferably 5 to 9 kg / cm ^2. Can be fluorinated.

The fluorination reaction can be carried out in a batch system or a continuous system.

In the production method of the present invention, the fluorination can be carried out by reacting with HF in a gas phase using chromium fluoride (such as CrF ₃ ) as a catalyst for the fluorination reaction.

Using this catalyst, a pentahalogenopropane having a chlorine atom at the 3-position (eg, 1,1,1,3,3
-Chloropropane) in the gas phase, 1,1,1-trihalogen-3-chloropropene (eg 1,1,1-trifluoro-3-chloropropene) is obtained as the main product, When the above 1,1,1-trihalogeno-3,3-difluoropropane is used as a raw material,
1,1,1,3,3-pentafluoropropane can be obtained with good selectivity. This is considered to be due to the fact that in the 1,1,1-trihalogeno-3,3-difluoropropane, a chlorine atom does not exist at the 3-position and the trihalogenomethyl group is reactive.

In the production method of the present invention, the gas phase reaction using chromium fluoride as a catalyst for the fluorination reaction is carried out at a reaction temperature of 200 ° C. to 350 ° C. and a reaction pressure of atmospheric pressure to 10 kg / cm ^2. Is quite possible.

[0048]

EXAMPLES The present invention will be described below with reference to specific examples, but the present invention is not limited to the following examples.

Example 1 500 g of chloroform and 10 g of benzoyl peroxide were added to 5
The mixture was placed in a 00 mL autoclave and cooled with dry ice. Thereafter, the inside of the system was degassed and replaced with nitrogen.
Further, after degassing the inside of the system, vinylidene fluoride was introduced, and the pressure was adjusted to 10 kg / cm ² . Thereafter, the reaction temperature was gradually increased, and the reaction was carried out in the gas phase at 90 ° C. for 5 hours. During the reaction, vinylidene fluoride was appropriately added so that the pressure was maintained at 10 kg / cm ² .

After the reaction, the remaining vinylidene fluoride was removed, and the organic matter remaining in the autoclave was analyzed by GLC (gas phase-liquid phase chromatography: hereinafter the same).
Hereinafter, the results are shown.

CHCl ₃ 50.5% CCl ₃ CH ₂ CHF ₂ 25.6% CCl ₃ (CH ₂ CF ₂ ) ₂ H 16.5% CCl ₃ (CH ₂ CF ₂ ) ₃ H 7.4%

As described above, the conversion was 49.5% and the selectivity was 5
At 1%, 1,1,1-trichloro-3,3-difluoropropane was obtained. The crude product is then distilled to give 15
0.4 g of 1,1,1-trichloro-3,3-difluoropropane was obtained.

50 g of 1,1,1-trichloro-3,3-difluoropropane, 5 g of antimony pentafluoride and 100 g of HF thus obtained were put in a 200 mL autoclave, and the liquid phase was kept at 80 ° C. for 3 hours. In the reaction. At this time, the reaction pressure was set to 10 kg / cm ² , and the generated HCl was appropriately discharged out of the reaction system.

After the reaction, the generated organic matter was extracted through a washing tower together with HCl generated from the reactor and excess HF. After washing with water, the product was purified with a dry ice-acetone trap through a calcium chloride tower. The organic matter thus obtained was analyzed by GLC. Less than,
The analysis results (selectivity) are shown.

CF ₃ CH ₂ CHF ₂ (HFC-245fa) 99.2% CF ₂ ClCH ₂ CHF ₂ 0.5% CF ₃ CH = CHF 0.3%

Thus, 1,1,1-trichloro-
It was found that the target 1,1,1,3,3-pentafluoropropane (HFC-245fa) was obtained from 3,3-difluoropropane with an extremely high selectivity of 99.2%.

Example 2 10 g of benzoyl peroxide was placed in a 500 mL autoclave and cooled with dry ice. Thereafter, the system was degassed, and 430 g of fluorodichloromethane was introduced.
After that, nitrogen substitution was performed. Further, after deaeration of the system, 133 g of vinylidene fluoride was introduced. Thereafter, the reaction temperature was gradually increased, and the reaction was performed at 90 ° C. for 5 hours.

After the reaction, the remaining vinylidene fluoride was removed, and the organic matter remaining in the autoclave was analyzed by GLC. Hereinafter, the results are shown.

CHFCl ₂ 81.6% CFCl ₂ CH ₂ CHF ₂ 11.3% CFCl ₂ (CH ₂ CF ₂ ) ₂ H 6.2% CFCl ₂ (CH ₂ CF ₂ ) ₃ H 0.9%

Thus, the reaction rate was 18.4% and the selectivity was 6
1,1-Dichloro-1,3,3-trifluoropropane was obtained at 1%. The crude product was then distilled and 76 g
Of 1,1-dichloro-1,3,3-trifluoropropane was obtained.

50 g of 1,1-dichloro-1,3,3-trifluoropropane thus obtained, 5 g of antimony pentafluoride and 100 g of HF were placed in a 200 mL autoclave, and the solution was heated at 80 ° C. for 3 hours. The reaction was performed in phase. At this time, the reaction pressure was set to 10 kg / cm ² , and the generated HCl was appropriately discharged out of the reaction system.

After the reaction, the generated organic matter was extracted through a washing tower together with HCl generated from the reactor and excess HF. After washing with water, the product was purified with a dry ice-acetone trap through a calcium chloride tower. The organic matter thus obtained was analyzed by GLC. Less than,
The analysis results (selectivity) are shown.

CF ₃ CH ₂ CHF ₂ (HFC-245fa) 99.3% CF ₂ ClCH ₂ CHF ₂ 0.4% CF ₃ CH = CHF 0.3%

Thus, 1,1-dichloro-1,3,3
It was found that the target 1,1,1,3,3-pentafluoropropane (HFC-245fa) was obtained from 3-trifluoropropane with a very high selectivity of 99.3%.

Example 3 10 g of benzoyl peroxide was placed in a 500 mL autoclave and cooled with dry ice. Thereafter, the inside of the system was degassed, and 360 g of difluorochloromethane was introduced.
After that, nitrogen substitution was performed. Further, after deaeration of the system, 133 g of vinylidene fluoride was introduced. Thereafter, the reaction temperature was gradually increased, and the reaction was performed at 90 ° C. for 5 hours.

After the reaction, the remaining vinylidene fluoride was removed, and the organic matter remaining in the autoclave was analyzed by GLC. Hereinafter, the results are shown.

CHF ₂ Cl 85.3% CF ₂ ClCH ₂ CHF ₂ 9.4% CF ₂ Cl (CH ₂ CF ₂ ) ₂ H 3.3% CF ₂ Cl (CH ₂ CF ₂ ) ₃ H 2.0%

As described above, the reaction rate was 14.7% and the selectivity was 6
At 4%, 1-chloro-1,1,3,3-tetrafluoropropane was obtained. Next, the crude product was distilled to obtain 1-chloro-1,1,3,3-tetrafluoropropane.

The thus obtained 1-chloro-1,
50 g of 1,3,3-tetrafluoropropane, 5 g of antimony pentafluoride, and 100 g of HF were put in a 200 mL autoclave and reacted at 80 ° C. for 3 hours in a liquid phase. At this time, the reaction pressure was set to 10 kg / cm ² , and the generated HCl was appropriately discharged out of the reaction system.

After the reaction, the generated organic matter was extracted through a washing tower together with HCl generated from the reactor and excess HF. After washing with water, the product was purified with a dry ice-acetone trap through a calcium chloride tower. The organic matter thus obtained was analyzed by GLC. Less than,
The analysis results (selectivity) are shown.

CF ₃ CH ₂ CHF ₂ (HFC-245fa) 99.3% CF ₂ ClCH ₂ CHF ₂ 0.2% CF ₃ CH = CHF 0.5%

Thus, 1-chloro-1,1,3,3
-It was found that 1,1,1,3,3-pentafluoropropane (HFC-245fa) as a target product was obtained from tetrafluoropropane with an extremely high selectivity of 99.3%.

Example 4 In the same procedure as in Example 1, 1,1,1-trichloro-3,
After obtaining 3-difluoropropane, it was fluorinated. However, 300 g of SbF ₂ Cl ₃ was used as a fluorinating agent instead of 5 g of antimony pentafluoride and 100 g of HF. The analysis results (selectivity) of the organic substance thus obtained by GLC are shown below.

CF ₃ CH ₂ CHF ₂ (HFC-245fa) 96.2% CF ₂ ClCH ₂ CHF ₂ 1.5% CF ₃ CH = CHF 2.3%

Thus, as the fluorination catalyst, SbF ₂
Even when Cl ₃ was used, it was found that 1,1,1,3,3-pentafluoropropane (HFC-245fa) as a target product could be obtained with an extremely high selectivity of 96.2%.

Example 5 In the same procedure as in Example 1, 1,1,1-trichloro-3,
After obtaining 3-difluoropropane, it was fluorinated. However, instead of HF as a fluorinating agent, SbF ₃
300 g of (antimony trifluoride) was used. The analysis results (selectivity) of the organic substance thus obtained by GLC are shown below.

CF ₃ CH ₂ CHF ₂ (HFC-245fa) 94.3% CF ₂ ClCH ₂ CHF ₂ 3.5% CF ₃ CH = CHF 2.2%

Thus, as the fluorination catalyst, SbF ₃
It was also found that the target product 1,1,1,3,3-pentafluoropropane (HFC-245fa) can be obtained with a very high selectivity of 94.3% even when is used. It was also found that the reaction vessel was not corroded at all.

Example 6 In the same procedure as in Example 1, 1,1,1-trichloro-3,
3-Difluoropropane was obtained. And the diameter 20mm
Chromium fluoride (2mm x 2mm diameter tablet)
20 g were charged and kept at 350 ° C. under a predetermined pressure. Next, the above 1,1,1-trichloro-3,3-difluoropropane is gasified, and 50 mL / min in gas phase,
HF was also mixed in the gas phase at 250 mL / min and passed through the reaction tube.

The produced organic matter was extracted through a washing tower together with the produced HCl and excess HF. After washing with water, the product was purified with a dry ice-acetone trap through a calcium chloride tower. The organic matter thus obtained was analyzed by GLC. Hereinafter, the analysis results (selectivity) are shown.

CF ₃ CH ₂ CHF ₂ (HFC-245fa) 62.1% CF ₃ CH = CHCl 21.3% CF ₃ CH = CHF 16.6%

As described above, even when the gas phase reaction is carried out using chromium fluoride as the fluorination catalyst, 62.1%
1,1,1,3,3 which is the target with very high selectivity
Pentafluoropropane (HFC-245fa) was found to be obtained.

Examples 7 to 9 In the same procedure as in Example 1, 1,1,1-trichloro-
After obtaining 3,3-difluoropropane, it was fluorinated. However, the temperature of the fluorination reaction is 40 ° C, 60 ° C,
The temperature was changed to 100 ° C. The results of analysis of the selectivity of each organic material thus obtained by GLC are shown below.

[0084]

As described above, the reaction temperature was set to 40 ° C., 60 ° C.,
Even at 100 ° C., the target product 1,1,1,3,3-pentafluoropropane (H
FC-245fa) was found to be obtained. However,
Since the pressure changes as the reaction temperature changes, the reaction pressure at that time is also shown.

Examples 10 to 11 In the same procedure as in Example 1, 1,1,1-trichloro-
After obtaining 3,3-difluoropropane, it was fluorinated. However, the reaction time of the fluorination reaction was changed to 2 hours and 4 hours, respectively. The results of analysis of the selectivity of each organic material thus obtained by GLC are shown below.

[0087]

As described above, even when the reaction time is set to 2 hours or 4 hours, the target compound 1, 1 having a very high selectivity is obtained.
1,1,3,3-pentafluoropropane (HFC-2
45fa) was obtained.

Comparative Example 1 In Example 1, 1,1,1-trichloro-3,3-
Instead of difluoropropane, 1,1,1,3,3-pentachloropropane is added together with antimony pentafluoride and HF.
The mixture was placed in a 00 mL autoclave and reacted at 80 ° C. for 3 hours. At this time, the reaction pressure was set to 10 kg / cm ² , and the generated HCl was appropriately discharged out of the reaction system.

After the reaction, the generated organic matter was extracted through a washing tower together with HCl generated from the reactor and excess HF. After washing with water, pass through a calcium chloride tower and dry ice
The product was purified with an acetone trap. The organic matter thus obtained was analyzed by GLC. Hereinafter, the analysis result of the selectivity is shown.

CF ₃ CH ₂ CHF ₂ (HFC-245fa) 78% CF ₃ CH ₂ CHFCl 18% Others 4%

As described above, when 1,1,1,3,3-pentachloropropane having a chlorine atom at the 3-position is used as a starting material for the fluorination reaction, the fluorination under the same conditions as in Example 1 is performed. Despite the reaction, the target 1,1,1,3,3-pentafluoropropane (HFC-245fa) was obtained only at a low selectivity.

Comparative Example 2 In the same manner as in Example 6, a reaction tube having a diameter of 20 mm was filled with 20 g of chromium fluoride (tabletting product of 2 mm × 2 mm in diameter), and kept at 350 ° C. under a predetermined pressure. Next, 1,1,1-
1,1 instead of trichloro-3,3-difluoropropane
Gasification of 1,1,3,3-pentachloropropane, 10 mL / min in gas phase, 250 mL of HF in gas phase
/ Min and passed through the reaction tube. The organic matter thus obtained was analyzed by GLC. Hereinafter, the analysis result of the selectivity is shown.

CF ₃ CH ₂ CHF ₂ (HFC-245fa) 6.2% CF ₃ CH = CHCl 80.5% CF ₃ CH = CHF 13.3%

As described above, when 1,1,1,3,3-pentachloropropane having a chlorine atom at the 3-position is used as a starting material for the fluorination reaction, 1,1,1-trifluoro-3 -Chloropropene as the main product
It is obtained with a selectivity of 5%.
3,3-pentafluoropropane (HFC-245f
a) was only obtained with a low selectivity (6.2%).

[0096]

According to the production method of the present invention,
Formula: CH (X¹) (X^Two) (X^Three)  (However, X¹, X^Two, X^ThreeAre different or the same
Is a halogen atom and all are fluorine atoms
Absent. ) (For example, chloropho
And vinylidene fluoride)
(CF_Two= CH_Two) (Particularly radical reactions)
A), 1,1,1-trihalogeno-3,
3-difluoropropane (CHX_ThreeCH_TwoCHF_Two)
Useful as refrigerant, blowing agent, cleaning agent, etc. because it is fluorinated
Useful compounds that can serve as alternative compounds such as
1,1,1,3,3-pentafluoropropane (CF_Three
CH_TwoCHF_Two) Can be manufactured efficiently and economically.
Can be.

Continuation of the front page (51) Int.Cl. ⁶ Identification symbol FI // C07B 61/00 300 C07B 61/00 300

Claims (12)

[Claims] 1. A compound of the general formula: CH (X¹) (X^Two) (X^Three)  (However, X¹, X^Two, X^ThreeAre different or the same
Is a halogen atom and all are fluorine atoms
Absent. ) And vinylidene fluoride
1,1,1-trihalo obtained by addition reaction with
Fluorinating geno-3,3-difluoropropane,
How to make 1,1,1,3,3-pentafluoropropane
Law. 2. The method according to claim 1, wherein the addition reaction is a radical reaction. 3. The method according to claim 1, wherein the trihalomethane is a compound selected from the group consisting of chloroform, fluorodichloromethane, and difluorochloromethane. 4. As a reaction initiator of the radical reaction,
3. The method according to claim 2, wherein an organic carboxylic acid peroxide is used. 5. Use of a metal fluoride and / or hydrogen fluoride as a fluorinating agent, and performing the fluorination in a liquid phase.
The method according to claim 1. 6. The method according to claim 5, wherein antimony fluoride is used as the metal fluoride salt. 7. The method according to claim 1, wherein the fluorination is performed using a metal halide salt and / or hydrogen fluoride. 8. The method according to claim 7, wherein an antimony halide is used as the metal halide salt. 9. The method according to claim 8, wherein antimony fluoride is used as the antimony halide in a liquid phase. 10. The method according to claim 7, wherein the fluorination is performed in a gas phase using chromium fluoride as the metal halide salt. 11. The fluorination is carried out at a reaction temperature of 40 ° C. to 100 ° C. and a reaction pressure of ² to ²⁰ kg / cm ^2.
Or the manufacturing method described in 7. 12. The fluorination is carried out at a reaction temperature of 200 ° C. to 350 ° C. and a reaction pressure of atmospheric pressure to 10 kg / cm ² .
The method according to claim 10.