JPH02204423A - Production of chlorinated pentafluoropropanes - Google Patents

Abstract

PURPOSE:To obtain the subject compound useful as a foaming agent, refrigerant, detergent, etc., in high purity and yield without necessitating multi-stage purification process by using a specific hydrogen-containing pentafluoropropane compound as a raw material and chlorinating the material in the presence of a radical generation source. CONSTITUTION:The objective compound is produced by using a hydrogen containing pentafluoropropane compound having difluoromethylene group C3 HmCl3-mF5; 1<=m<=3) as a raw material and substituting the hydrogen atom of the raw material to chlorine atom with chlorine in the presence of a radical generation source (preferably alpha,alpha'-azobisisobutyronitrile, 2,2-azobis-2,4- dimethylvaleronitrile, di-t-butyl peroxide, etc.). Concrete examples of the above raw material are 1,1,2,2,3-pentafluoropropane and 1,1-dichloro-1,2,2,3,3- pentafluoropropane.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for producing chlorinated pentafluoropropanes having a difluoromethylene group. Chlorinated pentafluoropropanes are expected to be used as blowing agents, refrigerants, cleaning agents, etc., similar to conventionally used fluorocarbons.

[Prior art and problems to be solved by the invention] In the synthetic route 1- of chlorinated pentafluoropropanes having a difluoromethylene group, 1-chloro-1,2,2- ) A synthesis method is known in which chlorodifluoromethane or the like is added to ethylene having a difluoromethylene unit such as refluoroethylene. However, this method produces a reaction by-product containing a methylene group other than difluoromethylene, which has a boiling point close to that of the desired product, at the same time as the desired product, so multiple purification steps are required to obtain a highly pure product. It has drawbacks.

[Means for Solving the Problems] The present inventor has developed chlorinated pentafluoropropanes having a difluoromethylene group (C3H-Cl3-, lFS;
≦n≦2) As a result of intensive studies on efficient production methods for hydrogen-containing pentafluoropropanes having a difluoromethylene group (C3H, Ct 3-sF5; 1≦m
≦3) by replacing hydrogen atoms with chlorine atoms in the presence of a radical generating source, it has been found that chlorinated pentafluoropropanes having a difluoromethylene group can be obtained in high yield, and the present invention is provided. This is what led to this.

Hereinafter, the present invention will be described in detail along with examples.

That is, it has been found that when hydrogen-containing pentafluoropropanes having a difluoromethylene group are chlorinated with chlorine, chlorinated pentafluoropropanes having a difluoromethylene group are produced in good yield as shown in the following formula.

CsH-mF3--Fs--C3HI, Ct
3--Fs1≦San≦3 0≦1≦2 In this reaction, a radical generating source such as light, heat, a radical initiator, or a combination thereof can be used. The radical initiator is not particularly limited as long as it is oil-soluble, but azo compounds or organic peroxides are usually used. Examples of azo compounds include α-α゛-azobisisobutyronitrile (hereinafter abbreviated as AIBN),
2,2-azobis-2,4-dimethylvaleronitrile (
(abbreviated as ADVN) and the like are preferred, and as the organic peroxide, for example, di-t-butyl peroxide and the like are preferred.

Hydrogen-containing pentafluoropropanes having a difluoromethylene group (C3H-mF3-Fs: 1≦
m≦3), 1.1.2.2.3-pentafluoropropane (R245ca), i, i, 1.2.
2-pentafluoropropane (R-245cb), 1-
Chloro-1,2,2,3,3-pentafluoropropane (R-235ca), l-chloro-2,2,3,3,3
-Pentafluoropropane (R-235cb), l-
Chloro-i, i, 2゜2.3-pentafluoropropane (R-235cc), 1.1-dichloro-2,2,
3,3,3-pentafluoropropane (R-225ca
), 1,3-dichloro-1,1,2,2,3-pentafluoropropane (R-225cb), 1. l-dichloro-1,2,2,3,3-pentafluoropropane (R-
225cc), all of which are known compounds.

The proportions of chlorine and raw materials can vary widely. . To perform selective chlorination in only one step, chlorine can be replaced with hydrogen-containing pentafluoropropanes (CsH) having a difluoromethylene group.
-mFa-Fs: 1≦Lotus≦3) is used in a low stoichiometric amount, but in order to almost completely react the hydrogen atoms of hydrogen-containing pentafluoropropanes having a difluoromethylene group, all of the starting material is An amount larger than the stoichiometric amount based on the number of moles may be used, for example, twice the mole or more.

The reaction temperature can be selected depending on the radical generation source used1
Usually -30 to 500°C, preferably -30 to 150°C when using light or a radical initiator as a radical generation source, and 200 to 150°C when generating radicals by heat.
In the present invention, which is particularly preferred at 450°C, a solvent may be used when the reaction is carried out in a liquid phase.In this case, the solvent dissolves the raw material propane and, if a radical initiator is used, as well. There is no particular limitation as long as the solvent itself is not easily chlorinated. For example, carbon tetrachloride and the like are suitable.

The reaction pressure is not particularly limited when the reaction is carried out in the gas phase, and can range from reduced pressure to increased pressure. When the reaction is carried out in the liquid phase, it is sufficient to select the reaction pressure so that the raw material hydrogen-containing pentafluoropropanes is sufficiently present in the liquid phase, and the It varies depending on the type, etc.

Chlorinated pentafluoropropanes (Cs HnmFa-nF) having a difluoromethylene group produced by the reaction
s: 0≦n≦2), 1-chloro-1,2゜2
, 3.3-pentafluoropropane (R-235ca)
l-chloro-2,2,3,3,3-pentafluoropropane (R-235c'b), 1-chloro-1,1,2,
2,3-pentafluoropropane (R-235cc),
1,1-dichloro-2,2,3,3,3-pentafluoropropane (R-225Ca), 1,3-dichloro-
1,1,2,2,3-pentafluoropropane (R-2
25cb), 1,1-dichloro-1,2,2,3,3
-Pentafluoropropane (R-22, 5c c >,
, 1.1.3-trichloro-1,2,2,3,3-pentafluoropropane (R-215ca), 1.1.1-
Trichloro-2,2,3,3,3-pentafluoropropane (R-215cb) is mentioned, and these can be separated by ordinary operations such as distillation.

[Example] Examples of the present invention will be shown below.

Example 1 A 1000CC glass reactor equipped with a -50°C condenser was cooled to -20°C and the temperature was 1.1.2°2.3.
- After charging 300 g of pentafluoropropane, 5
80 g of chlorine gas was gradually introduced while stirring under light irradiation with a 00 W high-pressure mercury lamp. After 6 hours of reaction,
The product after removing the acid content was subjected to gas chromatography and 19F-NM.
It was analyzed using R,IH-NMR. The results are shown in Table 1.

Example 2 1,1.2.2.3-pentafluoropropane 300
The reaction was carried out for 6 hours in the same manner as in Example 1, except that 160 g of chlorine gas and 160 g of chlorine gas were used. The product was subjected to gas chromatography and 1'F
-NMR and IH-NMR. Results first
Shown in the table.

Example 3 1,1.2.2.3-pentafluoropropane 300
The reaction was carried out for 6 hours in the same manner as in Example 1, except that 320 g of chlorine gas and 320 g of chlorine gas were used. The product was subjected to gas chromatography and 19F-
It was analyzed using NMR, IH-NMR, and the results are shown in Table 1.

Example 4 300 g of 1,1.2.2.3-pentafluoropropane
and 160g of chlorine gas, CCl420 as reaction solvent
The reaction was carried out for 6 hours in the same manner as in Example 1, except that 0 g was used. The product was analyzed by gas chromatography and 19F-NMRlIH-N.
Analyzed using MR. The results are shown in Table 1.

Table 1 Example 5 1. In a 1000CC Hastelloy-C autoclave.
1.2.2. After charging 300 g of 3-pentafluoropropane and 20 g of di-t-butyl peroxide,
Raise the temperature to 20℃ and add 200 ml of chlorine gas while stirring.
g was fed at a rate of 50 g/hour over 4 hours, and the reaction was continued for an additional 12 hours. The product after removing the acid content was analyzed using gas chromatography and 19F-NMRlIH-NMR. The results are shown in Table 2.

Example 6 1.1.2.2.3-pentafluoropropane 300
200 g of chlorine gas to 50 g in the same manner as in Example 5, except that 20 g of AlBN was used as the radical initiator.
The reactor was supplied for 4 hours at a rate of 1/hour, and the reaction was continued for an additional 12 hours. The product was analyzed by gas chromatography and 19F-NMR, IH-
Analyze using NMR. The results are shown in Table 2.

Example 7 A reactor made of Inconel 600 with an inner diameter of 1.27 cm and a length of 20 cm was maintained at 430°C, and gasified 1, 1.2° 2.3-bentatefluoropropane and chlorine gas were each heated at 150 rI12/min. The mixture was supplied and reacted continuously for 4 hours. The product after removing the vi component was subjected to gas chromatography and '9F
-NMR and IH-NMR. Second result
Shown in the table.

Table 2 Example 8 1,1.1.2.2-pentafluoropropane 300
The reaction was carried out for 6 hours in the same manner as in Example 1, except that 160 g of chlorine gas and 160 g of chlorine gas were used. The product was subjected to gas chromatography and 19F
-NMR, was analyzed using IH-NMR. The results are shown in Table 2.

A reaction was carried out for 6 hours in the same manner as in Example 1, except that 300 g of Table 2 and 65 g of chlorine gas were used. Gas chromatography and 1
It was analyzed using 9F-NMR and IH-NMR. The results are shown in Table 4.

Table 4 Example 9 A reaction was carried out for 6 hours in the same manner as in Example 1, except that 300 g of 1-chloro-1,2,2,3,3-pentafluoropropane and 130 g of chlorine gas were used. The product was analyzed using gas chromatography and F-NMR, IH-NMR, and the results are shown in Table 3.

Table 3 Example 11 A reaction was carried out for 6 hours in the same manner as in Example 1, except that 300 g of 1-chloro-1,1,2,2,3-pentafluoropropane and 65 g of chlorine gas were used. The product was analyzed using gas chromatography and 19F-NMR, II-(-NMR). The results are shown in Table 6.

Table 6 Example 10 1-chloro-2,2,3,3,3-pentafluoropropane Example 12 300 g of 1,1-dichloro-2,2,3,3,3-pentafluoropropane and 105 g of chlorine gas The reaction was carried out for 6 hours in the same manner as in Example 1, except that . The product was analyzed using gas chromatography and 19F-NMRlIH-NMR. The results are shown in Table 7.

Table 7 Example 14 A reaction was carried out for 6 hours in the same manner as in Example 1, except that 300 g of 1,1-dichloro-1,2,2,3,3-pentafluoropropane and 105 g of chlorine gas were used. The product was analyzed using gas chromatography and 19F-NMRlIH-NMR. The results are shown in Table 9.

Table 9 Example 13 A reaction was carried out for 6 hours in the same manner as in Example 1, except that 300 g of 1,3-dichloro-1,1,2,2,3-pentafluoropropane and 105 g of chlorine gas were used. The product was analyzed using gas chromatography and I"F-NMR, IH-NMR. The results are shown in Table 8.

Table 8 [Effects of the Invention] The present invention shows that chlorinated pentafluoropropanes having a difluoromethylene group can be selectively produced by chlorinating hydrogen-containing pentafluoropropanes having a difluoromethylene group as raw materials. have an effect.

Claims (1)

[Claims] 1. Hydrogen-containing pentafluoropropanes having a difluoromethylene group (C_3H_mCl_3_-_mF_5;
Chlorinated pentafluoropropanes (C_3H_nCl_3_-_
nF_5; 0≦n≦2) manufacturing method. 2. The manufacturing method according to claim 1, wherein the hydrogen-containing pentafluoropropane having a difluoromethylene group is 1,1,2,2,3-pentafluoropropane. 3. The manufacturing method according to claim 1, wherein the hydrogen-containing pentafluoropropane having a difluoromethylene group is 1,1,1,2,2-pentafluoropropane. 4. The manufacturing method according to claim 1, wherein the hydrogen-containing pentafluoropropane having a difluoromethylene group is 1-chloro-1,2,2,3,3-pentafluoropropane. 5. The production method according to claim 1, wherein the hydrogen-containing pentafluoropropane having a difluoromethylene group is 1-chloro-2,2,3,3,3-pentafluoropropane. 6. The manufacturing method according to claim 1, wherein the hydrogen-containing pentafluoropropane having a difluoromethylene group is 1-chloro-1,1,2,2,3-pentafluoropropane. 7. Hydrogen-containing pentafluoropropanes having a difluoromethylene group are 1,1-dichloro-2,2,3,3,3
- The manufacturing method according to claim 1, which is pentafluoropropane. 8. Hydrogen-containing pentafluoropropanes having a difluoromethylene group are 1,3-dichloro-1,1,2,2,3
- The manufacturing method according to claim 1, which is pentafluoropropane. 9. Hydrogen-containing pentafluoropropanes having a difluoromethylene group are 1,1-dichloro-1,2,2,3,3
- The manufacturing method according to claim 1, which is pentafluoropropane.