Sulfate compounds and methods for their preparation

Abstract

The application relates to the technical field of organic synthesis, in particular to a sulfate compound and a preparation method thereof; the preparation method comprises the following steps: adding an ether compound shown in formula II into a reaction kettle, adding concentrated sulfuric acid drop by drop under a certain temperature, continuously reacting until the reaction is completed to obtain a compound shown in formula I; wherein R4 / R5 in formula II is selected from F or Cl, R1, R2, R3, R6, R7 and R8 in formula I and formula II are selected from H, F, Cl, a straight-chain or branched alkyl with 1-3 carbon atoms or a halogen-substituted straight-chain or branched alkyl with 1-3 carbon atoms; the reaction does not need to add a catalyst, the reaction condition is mild, the equipment is simple, and since the reaction is a normal-pressure reaction, the reaction condition can be monitored at any time, the reaction can be completely reacted at one time, secondary recovery treatment is avoided, and the loss of raw materials is obviously reduced.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of organic synthesis, and particularly relates to a sulfate compound and a preparation method thereof. BACKGROUND

[0002] Hydrofluoroethers have low GWP, zero ODP, and very short atmospheric residence time, and are considered as one of the substitutes for existing HFCs type refrigerants. In addition, hydrofluoroethers are also used as anesthetics, cleaning agents and the like. In the process of synthesizing hydrofluoroethers, a stable new compound is accidentally prepared after mixing hydrofluoroethers with concentrated sulfuric acid, and the structure of the compound is finally determined.

[0003] The new compound is not disclosed in the processes of preparing sulfate compounds by reacting ethers with sulfuric acid in the prior art, and specifically as follows:

[0004] Patent CN2014107151695 discloses a preparation method of 4,4-difluoroacetyl alkyl acetate, and specifically discloses that "sulfuric acid is added into a reaction device, then water and 1,1,2,2-tetrafluoroethyl ethyl ether are sequentially added, a hydrolysis reaction is performed, and difluoroacetic ethyl ester and hydrogen fluoride are separated". The method for preparing difluoroacetic ethyl ester in the patent is a hydrolysis reaction under acidic conditions, and sulfuric acid is used as a catalyst, which is completely different from the use of sulfuric acid as a reactant in the preparation method of the application.

[0005] And the article "Research on synthesis of difluoroacetic ethyl ester from tetrafluoroethylene" in Organic Fluorine Industry, No. 4, 2017, points out that if sulfuric acid participates in the reaction, the concentration of the sulfuric acid must be more than 90%, and based on the above analysis, it can be further reasonably concluded that the sulfuric acid in the patent is only used as a catalyst and not as a reactant, and the compound protected in the application is not formed in the reaction process.

[0006] In the preparation of difluoroacetic ethyl ester in the article "Synthesis research of difluoroacetic ethyl ester" in Organic Fluorine Industry, No. 1, 2017, it can be known from the content recorded in the article that the role of concentrated sulfuric acid is a catalyst, and according to the reaction mechanism, the compound protected in the application is not generated.

[0007] Based on this, the sulfate compound and the preparation method thereof are researched in the application. SUMMARY

[0008] The application aims to provide a sulfate compound and a preparation method thereof, and to fill the blank in the industry.

[0009] To achieve the above object, the technical scheme adopted by the application is as follows:

[0010] A sulfate compound, the structure of the compound is shown as formula I,

[0011]

[0012] Wherein: R1, R2, R3, R6, R7, R8 are selected from one of H, F, Cl, C1-C3 linear or branched alkyl, halogen-substituted C1-C3 linear or branched alkyl.

[0013] A preparation method of a sulfate compound, the reaction formula is as follows:

[0014]

[0015] An ether compound shown as formula II is added into a reaction kettle, concentrated sulfuric acid is added dropwise at a certain temperature, and after the addition is completed, the reaction is continued until the reaction is completed, to obtain a compound shown as formula I;

[0016] Wherein: R4 / R5 in formula II is selected from F or Cl, R1, R2, R3, R6, R7, R8 in formula I and formula II are selected from one of H, F, Cl, C1-C3 linear or branched alkyl, halogen-substituted C1-C3 linear or branched alkyl.

[0017] Further, the compound of formula II includes the following compounds:

[0018] Further, the reaction temperature is 10-100 DEG C, and the concentration of concentrated sulfuric acid is 90-99%.

[0019] Further, the reaction temperature is 20-60 DEG C, and the concentration of concentrated sulfuric acid is 90-96%.

[0020] Further, the stirring speed is 150-180 rpm.

[0021] Further, the molar ratio of the ether compound shown as formula II and 95% concentrated sulfuric acid is 1:1-2.

[0022] Further, the molar ratio of the ether compound shown as formula II and 95% concentrated sulfuric acid is 1:1.5.

[0023] The beneficial effects of the technical scheme of the present application are:

[0024] The reaction of the present application does not need to add catalyst, the reaction condition is mild, the equipment is simple, and because the reaction is atmospheric pressure reaction, the reaction condition can be monitored at any time, in the present application, the gas chromatograph is used to analyze whether the raw material content is completely reacted, if not completely reacted, the reaction time can be prolonged or concentrated sulfuric acid is added, so that the reaction can be completely reacted at one time, avoiding secondary recovery treatment, significantly reducing the loss of raw materials, in addition, the tail gas generated in the reaction process can be absorbed by water, avoiding environmental pollution.

[0025] In addition, the compound in the present application is stable and easy to store, so it is convenient to be used as an intermediate for preparing many other compounds. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 The mass spectrum of the 2-chloro-(1,1-disulfate) ethyl-2,2,2-trifluoroethyl ether compound prepared in the present application.

[0027] Figure 2 The gas chromatogram of the 2-chloro-(1,1-disulfate) ethyl-2,2,2-trifluoroethyl ether compound prepared in Example 1. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present application will be clearly and completely described below in combination with specific embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0029] The raw materials in the present application are all ordinary commercial products.

[0030] 1,1,2,2-tetrafluoroethyl methyl ether 99%, 1,1,2,2-tetrafluoroethyl ethyl ether 99%, 1,1,2,2-tetrafluoroethyl-1,2,2-ethyl ether 99% (Shandong Huafu Chemical Industry Co., Ltd.)

[0031] 2-chloro-1,1-difluoroethyl methyl ether 99%, 2-chloro-1,1-difluoroethyl ethyl ether 99%, 2-chloro-1,1-difluoroethyl-2,2,2-trifluoroethyl ether 99% (Jiangsu Blue Star Environmental Protection Technology Co., Ltd.)

[0032] Figure 1 The mass spectrum of the 2-chloro-(1,1-disulfate) ethyl-2,2,2-trifluoroethyl ether compound prepared in the present application.

[0033] Figure 2Gas chromatogram of 2-chloro-(1,1-difluoroethyl)-2,2,2-trifluoroethyl ether compound prepared in Example 1.

[0034] Example 1

[0035] Into a 1 liter stirred carbon steel reaction vessel was charged 199 grams of 2-chloro-1,1-difluoroethyl-2,2,2-trifluoroethyl ether, and 155 grams of 95% concentrated sulfuric acid was added dropwise under stirring, while controlling the reaction temperature to be below 60°C. After the completion of the dropwise addition, the temperature was maintained at about 30°C, and the reaction was stirred for 4 hours to obtain a sulfuric acid ester product at a yield of 99%. During the reaction, the off-gas was absorbed with water.

[0036] Example 2

[0037] Into a 1 liter stirred carbon steel reaction vessel was charged 238 grams of 1,1,2,2-tetrafluoroethyl ethyl ether, and 248 grams of 95% concentrated sulfuric acid was added dropwise under stirring, while controlling the reaction temperature to be below 40°C. After the completion of the dropwise addition, the temperature was maintained at about 30°C, and the reaction was stirred for 2 hours to obtain a sulfuric acid ester product at a yield of 98%. During the reaction, the off-gas was absorbed with water.

[0038] Example 3

[0039] Into a 1 liter stirred carbon steel reaction vessel was charged 211 grams of 2-chloro-1,1-difluoroethyl phenyl ether, and 155 grams of 95% concentrated sulfuric acid was added dropwise under stirring, while controlling the reaction temperature to be below 60°C. After the completion of the dropwise addition, the temperature was maintained at about 30°C, and the reaction was stirred for 4 hours to obtain a sulfuric acid ester product at a yield of 98%. During the reaction, the off-gas was absorbed with water.

[0040] Example 4

[0041] Into a 5 liter stirred carbon steel reaction vessel lined with Teflon was charged 3500 grams of water, and 3580 grams of the sulfuric acid ester prepared in Example 1 was added dropwise under stirring over 1 hour, while controlling the reaction temperature to be below 30°C. After the completion of the dropwise addition, the reaction was left to stand, and the lower organic layer was separated to obtain 1589 grams of chloroacetic acid-2,2,2-trifluoroethyl ester at a yield of 90%.

[0042] In addition, it should be understood that although the specification is described in terms of embodiments, not every embodiment contains only one independent claim, and the specification is described in this manner only for clarity, and those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that those skilled in the art can understand.

Claims

1. A sulfate ester compound, characterized by: The structure of the compound is shown in formula I, Two of R6, R7 and R8 are H, and the other is CH3 or halogen-substituted methyl; one of R1, R2 and R3 is Cl, and the other two are H, or two of them are F, and the other is H. The preparation method of the sulfate compound comprises the following steps: An ether compound shown in formula II is added into a reaction kettle, concentrated sulfuric acid is added dropwise at a certain temperature, and the reaction is continued until the reaction is completed to obtain a compound shown in formula I; Two of R6, R7 and R8 are H, and the other is CH3 or halogen-substituted methyl; one of R1, R2 and R3 is Cl, and the other two are H, or two of them are F, and the other is H.

2. The sulfate ester compound according to claim 1, characterized by: The compounds of Formula II include the following compounds:

3. The sulfate compound according to claim 1, wherein: The reaction temperature is 10-100 ℃, and the concentration of the concentrated sulfuric acid is 90-99%.

4. The sulfate ester compound according to claim 3, characterized by: The reaction temperature is 20-60 ℃, and the concentration of the concentrated sulfuric acid is 90-96%.

5. The sulfate ester compound according to claim 1, characterized by: The stirring speed is 150-180 rpm.

6. The sulfate ester compound according to claim 1, characterized by: The molar ratio of the ether compound shown in formula II to 95% concentrated sulfuric acid is 1:1-2.

7. The sulfate ester compound according to claim 6, characterized by: The molar ratio of the ether compound shown in formula II to 95% concentrated sulfuric acid is 1:1.5.

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