WO2020138434A1 - Production method for haloalkyl acid halide, production method for haloalkyl acid ester, and production method for haloalkyl acid amide - Google Patents

Abstract

Provided is a production method with which a haloalkyl acid halide can be efficiently produced. In the present invention, a compound represented by formula 1: CBrX1X2-(CY1Y2)n-CHBrZ is irradiated in the presence of oxygen and a radical with light having a wavelength in the range of 260-400 nm to oxidize the compound, whereby a haloalkyl acid halide represented by formula 2: CBrX1X2-(CY1Y2)n-C(O)Z is produced. In formulas 1 and 2, each of X1, X2, Y1, Y2, and Z independently represents a fluorine atom, a chlorine atom, or a bromine atom, and n represents an integer of 0-4.

Description

Method for producing haloalkyl acid halide, method for producing haloalkyl acid ester, and method for producing haloalkyl acid amide

The present invention relates to a method for producing a haloalkyl acid halide, a method for producing a haloalkyl acid ester using the same, and a method for producing a haloalkyl acid amide.

Haloalkyl acid halides, and haloalkyl acid esters and haloalkyl acid amides derived from haloalkyl acid halides are useful as intermediates for various catalysts, pharmaceuticals, agricultural chemicals, lubricating oils and the like.

Patent Document 1 describes that C ₂ F ₅ CHCl ₂ is photooxidized to obtain an acid chloride (haloalkyl acid halide).
Patent Document 2 discloses a method for producing difluorobromoacetyl chloride (haloalkyl acid halide) by using 1,1-difluoro-1,2-dibromoethane as a starting compound and irradiating with ultraviolet light in the presence of chlorine and oxygen. Is listed.

International Publication No. 95/06629 Japanese Patent Laid-Open No. 5-320091

The method described in Patent Document 1 is a method using a raw material compound having a chlorine atom, and a method using a raw material compound having a bromine atom is not described. According to the findings of the present inventors, the starting compound having a bromine atom is more unstable than the starting compound having a chlorine atom, and it is difficult to control the reaction.
According to the knowledge of the present inventors, the method described in Patent Document 2 has a problem that the reaction is slow and it is difficult to obtain a high yield.

The present invention provides a production method capable of efficiently producing a haloalkyl acid halide, and a production method of a haloalkyl acid ester and a haloalkyl acid amide using the same.

The present invention has the following aspects.
[1] A haloalkyl which is obtained by oxidizing a compound represented by the following formula 1 by irradiating light having a wavelength within a range of 260 to 400 nm in the presence of oxygen and a radical to obtain a compound represented by the following formula 2. Method for producing acid halide.
CBrX ¹ X ² —(CY ¹ Y ² ) _n —CHBrZ Formula 1
CBrX ¹ X ² —(CY ¹ Y ² ) _n —C(O)Z Formula 2
[In Formula 1 and Formula 2, X ¹ , X ² , Y ¹ , Y ² , and Z each independently represent a fluorine atom, a chlorine atom, or a bromine atom, and n represents an integer of 0 to 4. [2] The method for manufacturing [1], wherein the light has a single wavelength. [3] The method for producing [1] or [2], wherein the oxidation is performed in a gas phase. [4] The production method of [1] or [2], wherein the oxidation is performed in a liquid phase. [5] The production method according to any one of [1] to [4], wherein the light irradiation is performed in the presence of at least one of a chlorine radical and a bromine radical. [6] The production method according to any one of [1] to [5], wherein Z is a chlorine atom. [7] The method according to any one of [1] to [6], wherein the compound represented by the formula 1 is 1,2-dibromo-2-chloro-1,1-difluoroethane. [8] A compound represented by the formula 2 is obtained by the production method according to any one of [1] to [7], and the compound represented by the formula 2 is reacted with a compound represented by the following formula 3. To obtain a compound represented by the following formula 4, a method for producing a haloalkyl ester.
R-OH formula 3
CBrX ¹ X ² -(CY ¹ Y ² ) _n -C(O)OR Formula 4
[In the formulas 3 and 4, R represents an alkyl group having 1 to 4 carbon atoms. X ¹ , X ² , Y ¹ , Y ² and n are the same as in the above formulas 1 and 2. ]

According to the present invention, a haloalkyl acid halide can be efficiently produced.
According to the present invention, a haloalkyl ester can be efficiently produced.

In the present specification and claims, the numerical range represented by “to” means a numerical range in which the numerical values before and after are the lower limit value and the upper limit value.
In the present specification and claims, “light having a single wavelength” means light having a difference between the shortest wavelength and the longest wavelength of 50 nm or less.
In the present specification, the compound represented by Formula 1 is also referred to as Compound 1. The compounds represented by other formulas will be described in the same manner.

<Method for producing haloalkyl acid halide>
The method for producing a haloalkyl acid halide of the present embodiment is a method for producing a compound 2 which is a haloalkyl acid halide by oxidizing the compound 1 which is a raw material compound.
The oxidation reaction of compound 1 is performed by a method of irradiating with light in the presence of oxygen and radicals.

CBrX ¹ X ² —(CY ¹ Y ² ) _n —CHBrZ Formula 1
CBrX ¹ X ² —(CY ¹ Y ² ) _n —C(O)Z Formula 2
In Formula 1 and Formula 2, X ¹ , X ² , Y ¹ , Y ² , and Z each independently represent a fluorine atom, a chlorine atom, or a bromine atom, and n represents an integer of 0 to 4.

It is preferable that Z is a chlorine atom from the viewpoint of easy handling of the reaction product.
Preferred examples of compound 1 include 1,2-dibromo-2-chloro-1,1-difluoroethane, 1,2,2-tribromo-1,1-difluoroethane, 1,2-dibromo-1,1,2- Examples include trifluoroethane and 1,2-dibromo-1,1-difluoroethane. Among them, 1,2-dibromo-2-chloro-1,1-difluoroethane (in the formula 1, X ¹ and X ² are fluorine atoms, Z is chlorine atom, and n is Compounds that are zero) are more preferred.

Oxygen (O ₂ ) used in the oxidation reaction is preferably 0.1 to 10 mol, more preferably 0.3 to 5 mol, and still more preferably 0.5 to 3 mol with respect to 1 mol of the compound 1. When it is at least the lower limit value of the above range, the conversion rate tends to be high, and when it is at most the upper limit value, the selectivity rate tends to be high.

In order to allow oxygen to exist in the reaction system, it is preferable to introduce an oxygen-containing gas into the reaction system. The oxygen-containing gas may be oxygen gas (O ₂ ), or may be a mixed gas containing oxygen and a gas inert to the oxidation reaction (for example, nitrogen, helium, argon, carbon dioxide, etc.).

The radical used for the oxidation reaction is preferably 0.01 to 10 mol, more preferably 0.1 to 5 mol, and still more preferably 0.5 to 3 mol, relative to 1 mol of the compound 1. When it is at least the lower limit value of the above range, the conversion rate tends to be high, and when it is at most the upper limit value, the selectivity rate tends to be high.
The oxygen/radical molar ratio used in the oxidation reaction is preferably 0.1/1 to 100/1, more preferably 1/1 to 50/1, and further preferably 2/1 to 10/1 mol. Within the above range, the selectivity tends to be high.
It is preferable that the radical contains at least one of a chlorine radical and a bromine radical because the selectivity is likely to be high. More preferably, the radical is at least one of a chlorine radical and a bromine radical.

In order to allow radicals to exist in the reaction system, it is preferable to introduce a radical source that generates radicals into the reaction system by irradiation with light. It is preferable that the radical source contains at least one of chlorine (Cl ₂ ) and bromine (Br ₂ ). More preferably, the radical source is at least one of chlorine and bromine.
When the radical source is chlorine, the chlorine (Cl ₂ ) used for the oxidation reaction is preferably 0.1 to 10 mol, more preferably 0.3 to 8 mol, and 0.5 to 10 mol with respect to 1 mol of the compound 1. 6 mol is more preferred.
When the radical source is bromine, the amount of bromine (Br ₂ ) used in the oxidation reaction is preferably 0.01 to 10 moles, more preferably 0.1 to 8 moles, and 0.3 to 1 mole of Compound 1. 6 mol is more preferred.

The wavelength of light used for the oxidation reaction is in the range of 260 to 400 nm. That is, the light with which the reaction system is irradiated does not include light having a wavelength of less than 260 nm and does not include light having a wavelength of more than 400 nm.
In the present embodiment, the absorption wavelength of the product haloalkyl acid halide exists in the region of wavelength shorter than 260 nm. For this reason, when light having a wavelength shorter than 260 nm is irradiated during the reaction, the product is easily decomposed to generate a side reaction product, and the selectivity of the target product is likely to decrease. When the wavelength of light used for the oxidation reaction is 260 nm or more, decomposition of the product can be easily prevented. In particular, it is preferable to use light having a wavelength of 260 to 400 nm because light energy is high and reaction efficiency is good.

When the wavelength of the light is in the above range, the selectivity tends to be high. The wavelength of the light is more preferably within the range of 350 to 400 nm.
The light used for the oxidation reaction is preferably light having a single wavelength because the yield tends to be high. An LED (light emitting diode) is preferable as the light source having a single wavelength.
Irradiance of LED is preferably 50 ~ 200mW / cm ^2, more preferably 80 ~ 150mW / cm ^2. If the irradiance is above the lower limit of the above range, the conversion rate tends to increase, and if it is below the upper limit, there is no need to install special incidental equipment in the manufacturing equipment, which is preferable.
The irradiance of the LED can be measured using an ultraviolet integrating photometer (manufactured by Ushio Inc.).

The method for producing a haloalkyl acid halide according to this embodiment can be performed in a gas phase. It is preferable to carry out the reaction in the gas phase because the reaction time tends to be short.
For example, the light is irradiated to the mixed gas of the gaseous compound 1, the oxygen-containing gas, and the gaseous radical source in the reaction container. The irradiation of light may be continuous or intermittent.
When chlorine is used as a radical source in the gas phase reaction, chlorine (Cl ₂ ) used in the oxidation reaction is preferably 0.1 to 10 mol, more preferably 0.3 to 5 mol, per 1 mol of the compound 1. , 0.5 to 3 mol is more preferable, and 0.5 to 1 mol is particularly preferable.

When bromine is used as the radical source in the gas phase reaction, the amount of bromine (Br ₂ ) used in the oxidation reaction is preferably 0.01 to 10 mol, more preferably 0.1 to 5 mol, per 1 mol of the compound 1. , 0.3 to 3 mol is more preferable, and 0.5 to 1 mol is particularly preferable.
The pressure in the reaction vessel is preferably atmospheric pressure (atmospheric pressure) to 0.5 MPa (gauge pressure), more preferably atmospheric pressure to 0.3 MPa (gauge pressure). When the pressure is equal to or higher than the lower limit of the above range, it is not necessary to provide special auxiliary equipment to the manufacturing facility, and when the pressure is equal to or lower than the upper limit, the conversion rate tends to be high.

The temperature of the gas in the reaction vessel (reaction temperature) is preferably 80 to 200°C, more preferably 90 to 150°C. If the reaction temperature is above the lower limit of the above range, the conversion rate tends to increase, and if it is below the upper limit, the selectivity tends to increase.
The time during which the mixed gas is irradiated with light is defined as the reaction time. The reaction time in the case of intermittent irradiation with light is the total time during which the mixed gas is irradiated with light. Regarding the reaction time, it was confirmed by NMR analysis or gas chromatography analysis that the peak derived from the starting compound, Compound 1, was reduced, and the peak derived from the target compound, Compound 2, was generated, and the yield was maximized. It is preferable that it is the time until it becomes. The time until the maximum yield can be estimated in advance by a preliminary test. The reaction time is preferably 1 to 120 minutes, more preferably 5 to 60 minutes. If the reaction time is at least the lower limit of the above range, the conversion rate tends to be high, and if it is at most the upper limit, the yield tends to be high.
The liquid compound 2 is obtained by cooling and liquefying the gas after the reaction.

The method for producing a haloalkyl acid halide according to this embodiment can be performed in a liquid phase. It is preferable to carry out the reaction in the liquid phase from the viewpoint of the apparatus shape.
For example, in the reaction vessel, the light is irradiated while the reaction liquid containing the compound 1 in the liquid state, the oxygen-containing gas, and the mixed gas of the radical source in the gas state are brought into contact with each other in the liquid phase. The reaction solution after light irradiation contains Compound 2.
When chlorine is used as a radical source in the liquid phase reaction, chlorine (Cl ₂ ) used in the oxidation reaction is preferably 0.1 to 10 mol, more preferably 0.3 to 8 mol, per 1 mol of the compound 1. , 0.5 to 6 mol is more preferable.

When bromine is used as a radical source in the liquid phase reaction, it is preferably 0.1 to 10 mol, more preferably 0.3 to 8 mol, still more preferably 0.5 to 6 mol.
The pressure in the reaction vessel is preferably atmospheric pressure (atmospheric pressure) to 0.5 MPa (gauge pressure), more preferably atmospheric pressure to 0.3 MPa (gauge pressure). When the pressure is equal to or higher than the lower limit of the above range, it is not necessary to provide special auxiliary equipment to the manufacturing facility, and when the pressure is equal to or lower than the upper limit, the conversion rate tends to be high.
The temperature of the liquid in the reaction vessel (reaction temperature) is preferably 0 to 100°C, more preferably 20 to 80°C. If the reaction temperature is above the lower limit of the above range, the conversion rate tends to increase, and if it is below the upper limit, the selectivity tends to increase.

The reaction liquid may contain a solvent, if necessary. The solvent is preferably an organic solvent inert to light, and examples thereof include carbon tetrachloride, tetrachloroethylene, and 1,1,2-trichloro-1,2,2-trifluoroethane. Carbon tetrachloride is preferred because it has a shorter absorption wavelength. The reaction solution preferably does not contain a solvent.
The time during which the reaction solution is irradiated with light is defined as the reaction time. The reaction time is the same as above. The reaction time is preferably 10 to 500 minutes, more preferably 60 to 360 minutes. If the reaction time is at least the lower limit of the above range, the conversion rate tends to be high, and if it is at most the upper limit, the yield tends to be high.

<Method for producing haloalkyl ester>
The method for producing a haloalkyl acid ester of the present embodiment is a haloalkyl acid ester obtained by oxidizing compound 1 to obtain compound 2 by the above-mentioned method for producing a haloalkyl acid halide and subjecting the obtained compound 2 to an esterification reaction. This is a method for obtaining compound 4.
In the esterification reaction, compound 2 and compound 3 are reacted.
R-OH formula 3
CBrX ¹ X ² -(CY ¹ Y ² ) _n -C(O)OR Formula 4

In Formulas 3 and 4, R represents an alkyl group having 1 to 4 carbon atoms, and X ¹ , X ² , Y ¹ , Y ² and n are the same as those in Formulas 1 and 2.
R is a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, an i-butyl group, or a t-butyl group. From the viewpoint that the reaction time tends to be short, a methyl group, an ethyl group, an n-propyl group, or an n-butyl group is preferable, and an ethyl group is more preferable.

In the present embodiment, the liquid compound 2 obtained by the above method is purified, if necessary, and used in the esterification reaction. Examples of the purification method include distillation.
In the esterification reaction, compound 2 and compound 3 can be reacted by a conventionally known method.
The compound 3 used in the esterification reaction is preferably 0.8 to 10 mol, more preferably 0.9 to 5 mol, still more preferably 1 to 2 mol, per 1 mol of the compound 2. If it is at least the lower limit of the above range, the yield tends to be high, and if it is at most the upper limit, purification is easy.

The temperature of the reaction liquid (reaction temperature), which is a mixture of compound 2 and compound 3, is preferably 0 to 50°C, more preferably 15 to 40°C. If the reaction temperature is above the lower limit of the above range, the reaction time tends to be short, and if it is below the upper limit, the yield tends to be high.
The reaction time is defined as the time during which the reaction solution is maintained at the reaction temperature. The reaction time is preferably the time until the peak derived from the starting compound, Compound 2, disappears by NMR analysis or gas chromatography analysis. The reaction time is preferably 1 to 100 minutes. If the reaction time is at least the lower limit of the above range, the conversion rate tends to be high, and if it is at most the upper limit, the yield tends to be high.

<Method for producing haloalkyl amide>
The method for producing a haloalkyl acid amide of the present embodiment is a haloalkyl acid amide obtained by oxidizing compound 1 to obtain compound 2 by the above-described method for producing a haloalkyl acid halide, and subjecting the obtained compound 2 to an amidation reaction. This is a method for obtaining compound 6.
In the amidation reaction, compound 2 and compound 5 are reacted.
R ¹ R ² —NH Formula 5
CBrX ¹ X ² —(CY ¹ Y ² ) _n —C(O)NR ¹ R ² Formula 6
In Formulas 5 and 6, R ¹ and R ² each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and X ¹ , X ² , Y ¹ , Y ² and n are the same as those in Formulas 1 and 2 above. Is.

R ¹ and R ² are each independently a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, an i-butyl group or a t-butyl group. A methyl group, an ethyl group, an n-propyl group, and an n-butyl group are preferable, and a methyl group or an ethyl group is more preferable, because the reaction time tends to be short. R ¹ and R ² may be the same or different, but are preferably the same.

In this embodiment, the liquid compound 2 obtained by the above method is purified as needed and used in the amidation reaction. Examples of the purification method include distillation.
Compound 5 may be a commercially available product, or can be produced by a known method.
In the amidation reaction, compound 2 and compound 5 can be reacted by a conventionally known method.
The compound 5 used in the amidation reaction is preferably 0.8 to 10 mol, more preferably 0.9 to 5 mol, still more preferably 1 to 2 mol, per 1 mol of the compound 2. If it is at least the lower limit of the above range, the yield tends to be high, and if it is at most the upper limit, purification is easy.

The temperature of the reaction liquid (reaction temperature), which is a mixture of the compound 2 and the compound 5, is preferably 0 to 50°C, more preferably 15 to 40°C. If the reaction temperature is above the lower limit of the above range, the reaction time tends to be short, and if it is below the upper limit, the yield tends to be high.
The reaction time is defined as the time during which the reaction solution is maintained at the reaction temperature. The reaction time is preferably the time until the peak derived from the starting compound, Compound 2, disappears by NMR analysis or gas chromatography analysis. The reaction time is preferably 1 to 100 minutes. If the reaction time is at least the lower limit of the above range, the conversion rate tends to be high, and if it is at most the upper limit, the yield tends to be high.

According to this embodiment, the compound 2 which is a haloalkyl acid halide can be efficiently produced by a novel method of oxidizing the compound 1 having a specific structure, and a haloalkyl acid ester or a haloalkyl acid amide can be produced using the compound 2. Can be manufactured efficiently.
For example, the yield in the production of compound 2 by oxidizing compound 1 can be improved to 30% or more, preferably 45% or more.
Haloalkyl acid halides, haloalkyl acid esters derived from haloalkyl acid halides, and haloalkyl acid amides derived from haloalkyl acid halides are useful as intermediates for various catalysts, pharmaceuticals, agricultural chemicals, lubricating oils, etc. is there.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.
<Examples 1-1, 1-2, 2 to 12>
Among these examples, Examples 1-1, 1-2, 2 to 5 are Examples, and Examples 6 to 12 are Comparative Examples. The structural formulas of the following compounds used or produced in each example are shown in Table 1.

[Example 1-1]
In this example, a haloalkyl acid halide (Compound 2-1) was produced using Compound 1-1 as a raw material compound, oxygen gas (O ₂ ) as an oxidizing agent, and chlorine gas (Cl ₂ ) as a radical source.
A glass reaction vessel with a capacity of 5000 mL equipped with a gas inlet and a gas outlet was preheated to 125°C. An LED light (manufactured by Nitride, wavelength 350-400 nm, installed on the outside of the reaction vessel while adjusting the mixed gas of compound 1-1, O ₂ and Cl ₂ to 120° C. and introducing the mixture gas into the reaction vessel at normal pressure. , Irradiance of 100 mW/cm ² , and the same in each of the following examples) was applied to the gas in the reaction vessel to carry out a gas phase reaction. The reaction container transmits light having a wavelength of 280 nm or more. The molar ratio of “compound 1-1/O ₂ /Cl ₂ ”in the mixed gas was 1/2.1/0.57. The mixed gas was continuously supplied into the reaction vessel at a flow rate of 212 mL/min, and the residence time in the reaction vessel was used as the reaction time. The reaction time was 23 minutes. The temperature of the gas in the reaction vessel was maintained at 100°C ± 10°C.
The gas discharged from the reaction container was collected in a trap whose temperature was adjusted to -70°C to obtain a liquid reaction product. The obtained liquid was analyzed by ¹⁹ F-NMR and gas chromatography. As a result, production of compound 2-1 was confirmed.
Table 2 shows the reaction time, conversion rate, selectivity and yield.

In this example, the conversion rate is a numerical value obtained by dividing the number of moles of the raw material compound used by the reaction (difference in the number of moles of the raw material compound before and after the reaction) by the number of moles of the raw material compound before the reaction, as a percentage. (Unit: %).
The selectivity is a numerical value (unit: %) in which a value obtained by dividing the number of moles of the produced haloalkyl acid halide by the number of moles of the raw material compound used in the reaction is expressed as a percentage.
The yield is a value obtained by dividing the number of moles of the produced haloalkyl acid halide by the number of moles of the raw material compound before the reaction, which is expressed as a percentage.
The same calculation was performed for Examples 2 to 6 and 8 to 12.

[Example 1-2]
In this example, the haloalkyl acid halide (Compound 2-1) obtained in Example 1-1 was esterified to produce a haloalkyl acid ester (Compound 4-1).
In Example 1-1, 74 g of a liquid reaction product was obtained. 62 g (containing 0.12 mol of compound 2-1) of the obtained liquid (25° C.) was transferred to a flask having a volume of 200 mL, and 6 g (0.13 mol) of ethanol was added for esterification. The temperature of the liquid in the flask (reaction temperature) was maintained at 30°C ± 10°C. The reaction time was 10 minutes.
The reaction solution immediately after the completion of the reaction was analyzed by ¹ H-NMR, ¹⁹ F-NMR and gas chromatography. As a result, production of compound 4-1 was confirmed.
The conversion, selectivity and yield in the esterification reaction were all 100%.

In the esterification reaction of this example, the conversion rate is defined as the number of moles of the haloalkyl acid halide used in the reaction (difference in the number of moles of the haloalkyl acid halide before and after the reaction). It is a numerical value (unit: %) in which the value divided by is expressed as a percentage.
The selectivity is a numerical value (unit: %) in which the value obtained by dividing the number of moles of the haloalkyl acid ester formed by the number of moles of the haloalkyl acid halide used in the reaction is expressed as a percentage.
The yield is a value obtained by dividing the number of moles of the haloalkyl acid ester formed by the number of moles of the haloalkyl acid halide before the reaction, which is expressed as a percentage.

[Example 2]
In this example, the oxidation reaction was performed in the liquid phase. A haloalkyl acid halide (Compound 2-1) was produced using a liquid compound 1-1 as a raw material compound, O ₂ as an oxidizing agent, and Cl ₂ as a radical source.
A glass reaction container having a capacity of 100 mL and equipped with a cooling tube cooled to −80° C., a gas inlet and a gas outlet was preheated to 60° C. 10 g (0.04 mol) of liquid compound 1-1 at 25° C. was charged, and O ₂ and Cl ₂ were introduced into the reaction vessel at 0.2 mol/hour, normal pressure and normal temperature (25° C.), respectively. In the same manner as in Example 1-1, the liquid crystal reaction was performed by irradiating the inside of the reaction vessel with the above LED light. The reaction container transmits light having a wavelength of 280 nm or more. The reaction time was 300 minutes. The molar ratio of "compound 1-1/O ₂ /Cl ₂ " used in the reaction was 1/10/5.

After the reaction, the liquid remaining in the reaction vessel was recovered to obtain a liquid reaction product. The obtained liquid was analyzed by ¹⁹ F-NMR and gas chromatography. As a result, production of compound 2-1 was confirmed.
Table 2 shows the reaction time, conversion rate, selectivity and yield in this example. Table 2 also shows the reaction time, conversion rate, selectivity and yield in each of the following examples.

[Example 3]
In Example 1-1, Br ₂ was used instead of Cl ₂ as the radical source. The molar ratio of “compound 1-1/O ₂ /Br ₂ ” in the mixed gas was set to 1/2.1/0.57. A haloalkyl acid halide (Compound 2-1) was produced in the same manner as in Example 1-1 except for the above.

[Example 4]
In Example 1-1, Compound 1-2 was used as the starting compound instead of Compound 1-1. The molar ratio of "compound 1-2/O ₂ /Cl ₂ "in the mixed gas was 1/2.1/0.57. Otherwise in the same manner as in Example 1-1, a haloalkyl acid halide (Compound 2-2) was produced.

[Example 5]
In Example 1-1, Compound 1-3 was used as the raw material compound instead of Compound 1-1. The molar ratio of “compound 1-3/O ₂ /Cl ₂ ”in the mixed gas was 1/2.1/0.57. Otherwise, in the same manner as in Example 1-1, a haloalkyl acid halide (Compound 2-3) was produced.

[Example 6]
In Example 1-1, the reaction was carried out without containing O ₂ in the mixed gas.
The molar ratio of “compound 1-1/Cl ₂ ”in the mixed gas was 1/0.57. A haloalkyl acid halide (Compound 2-1) was produced in the same manner as in Example 1-1 except for the above.
The method of calculating the conversion rate, selectivity and yield in this example is the same as in Example 1-1.

[Example 7]
In Example 1-1, the reaction was carried out without using O ₂ and Cl _2, but using fuming sulfuric acid as the oxidant, and iron(III) oxide as the catalyst.
In a glass-made reaction vessel having a volume of 200 mL, 19 g of fuming sulfuric acid having a concentration of 25% and 0.3 g of Fe ₂ O ₃ were placed and heated to 120°C. The reaction solution in the reaction vessel was maintained at 120° C., and 10 g of compound 1-1 was added dropwise over 30 minutes. The reaction was carried out by stirring for 4 hours and a half from the start of dropping.
The obtained liquid was analyzed by ¹⁹ F-NMR and gas chromatography. As a result, production of compound 5 was confirmed. No formation of compound 2-1 was observed.

[Example 8]
In Example 1-1, the reaction was performed without including Cl ₂ in the mixed gas.
The molar ratio of "compound 1-1/O ₂ "in the mixed gas was 1/3.7. A haloalkyl acid halide (Compound 2-1) was produced in the same manner as in Example 1-1 except for the above.

[Example 9]
In Example 1-1, the gas phase reaction was carried out without irradiation of the LED light. A haloalkyl acid halide (Compound 2-1) was produced in the same manner as in Example 1-1 except for the above.

[Example 10]
In this example, the gas phase reaction was performed by irradiating light having a wavelength of less than 260 nm.
In Example 1-1, a high pressure mercury lamp (wavelength 245 to 255 nm) was used instead of the LED light. Further, the material of the reaction vessel was changed to quartz glass which transmits light having a wavelength of 250 to 700 nm. A haloalkyl acid halide (Compound 2-1) was produced in the same manner as in Example 1-1 except for the above.

[Example 11]
In this example, the gas phase reaction was performed by irradiating light with a wavelength of more than 400 nm.
In Example 1-1, a red LED (wavelength 550 to 700 nm) was used instead of the LED light. A haloalkyl acid halide (Compound 2-1) was produced in the same manner as in Example 1-1 except for the above.

[Example 12]
In Example 1-1, Compound 6 was used as the raw material compound instead of Compound 1-1. The molar ratio of "compound _{6 /} O 2 / Cl _2" in the mixed gas was 1/2 / 0.56. The temperature of the gas in the reaction vessel was maintained at 100°C ± 10°C. A haloalkyl acid halide (Compound 2-1) was produced in the same manner as in Example 1-1 except for the above.

As shown in the results of Table 2, in Examples 1-1 and 2 to 5 in which the haloalkyl acid halide was produced by the production method of the present embodiment, the conversion rate of the raw material compound, the selectivity of the haloalkyl acid halide and the yield were obtained. And the haloalkyl acid halide could be produced efficiently. Furthermore, in Example 1-2, the haloalkyl ester could be efficiently produced.
In addition, the entire contents of the specification, claims, drawings, and abstract of Japanese Patent Application No. 2018-247003 filed on December 28, 2018 are cited herein as disclosure of the specification of the present invention. , Take in.

Claims (15)

1. A haloalkyl acid halide obtained by oxidizing a compound represented by the following formula 1 by irradiation with light having a wavelength in the range of 260 to 400 nm in the presence of oxygen and a radical to obtain a compound represented by the following formula 2. Manufacturing method.
   CBrX ¹ X ² —(CY ¹ Y ² ) _n —CHBrZ Formula 1
   CBrX ¹ X ² —(CY ¹ Y ² ) _n —C(O)Z Formula 2
   [In Formula 1 and Formula 2, X ¹ , X ² , Y ¹ , Y ² , and Z each independently represent a fluorine atom, a chlorine atom, or a bromine atom, and n represents an integer of 0 to 4. ]
2. The manufacturing method according to claim 1, wherein the light has a single wavelength.
3. The manufacturing method according to claim 1 or 2, wherein the light is a light emitting diode (LED) having an irradiance of 50 to 200.
4. The manufacturing method according to any one of claims 1 to 3, wherein the oxidation is performed in a gas phase.
5. The manufacturing method according to claim 4, wherein the pressure (gauge pressure) is from normal pressure (atmospheric pressure) to 0.5 MPa.
6. The manufacturing method according to any one of claims 1 to 3, wherein the oxidation is performed in a liquid phase.
7. 7. The production method according to any one of claims 1 to 6, wherein the oxygen is present in an amount of 0.1 to 10 mol with respect to 1 mol of the compound represented by the formula 1.
8. The method according to any one of claims 1 to 7, wherein the radical is present in an amount of 0.1 to 10 mol per 1 mol of the compound represented by the formula 1.
9. The production method according to any one of claims 1 to 8, wherein the oxygen and the radical are present at a molar ratio of oxygen/radical of 0.1/1 to 100/1.
10. The method according to any one of claims 1 to 9, wherein the radical is at least one of a chlorine radical and a bromine radical.
11. The method according to any one of claims 1 to 10, wherein Z is a chlorine atom.
12. The compound represented by the formula 1 is 1,2-dibromo-2-chloro-1,1-difluoroethane, 1,2,2-tribromo-1,1-difluoroethane, 1,2-dibromo-1,1, The method according to any one of claims 1 to 11, which is 2-trifluoroethane or 1,2-dibromo-1,1-difluoroethane.
13. The production method according to any one of claims 1 to 12, wherein the compound represented by the formula 1 is 1,2-dibromo-2-chloro-1,1-difluoroethane.
14. A compound represented by the formula 2 is obtained by the production method according to any one of claims 1 to 13, and the compound represented by the formula 2 is reacted with a compound represented by the following formula 3. A method for producing a haloalkyl acid ester for obtaining a compound represented by the following formula 4.
    R-OH formula 3
    CBrX ¹ X ² -(CY ¹ Y ² ) _n -C(O)OR Formula 4
    [In the formulas 3 and 4, R represents an alkyl group having 1 to 4 carbon atoms. X ¹ , X ² , Y ¹ , Y ² and n have the same definitions as those in the above formulas 1 and 2. ]
15. 15. The production method according to claim 14, wherein R in the formula 4 is a methyl group, an ethyl group, an n-propyl group, or an n-butyl group.