Method for co-producing chlorosilane and iodoethane

Abstract

The invention relates to a method for co-producing chlorosilane and iodoethane. The method comprises the following steps: enabling tert-butyl dimethyl ethyoxyl silane (dimethyl vinyl ethyoxyl silane or tert-butyl diphenyl ethyoxyl silane) and thionyl chloride to enter a micro-channel reactor at the same time to react; rectifying the reaction liquid to obtain tert-butyl dimethyl chlorosilane (dimethyl vinyl chlorosilane or tert-butyl diphenyl chlorosilane) and diethyl sulfite; the method comprises the following steps: putting magnesium iodide into a reaction container, adding water to prepare a solution, starting stirring, and heating; slowly dropwise adding the byproduct diethyl sulfite; and after dropwise adding, reacting to obtain iodoethane.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of chemical materials, and in particular, relates to a method for co-production of chlorosilane and iodoethane. BACKGROUND

[0002] Tert-butyl dimethyl chlorosilane is an important silane reagent in organic synthesis, which realizes high-selective protection of hydroxyl, amino and other groups by virtue of the steric effect of tert-butyl group, is a standard reagent for synthesis of steroid drugs, polypeptides and the like, and is also used for synthesis of complex molecules such as nucleosides and sugars; as an intermediate for anti-AIDS drugs, antibiotics and liquid crystal materials, plays a pivotal role in the fields of medicine and fine chemical industry, and has mild deprotection conditions, better liquid stability than trimethyl chlorosilane, and the by-product can be recycled, so as to become a key connecting reagent for laboratory and industrial production with 'high-selective protection + controllable cost'.

[0003] Tert-butyl diphenyl chlorosilane is a silane reagent in organic synthesis, which forms a high-stability protecting group by virtue of the double steric hindrance of tert-butyl and phenyl groups, can resist strong acid, strong base and other harsh conditions, is used for synthesis of complex drugs such as paclitaxel side chain and weather-resistant liquid crystal materials, and although the cost is relatively high (800-1000 yuan per kilogram) and the deprotection requirement is high, it is irreplaceable in high-end raw pharmaceuticals and electronic chemicals due to reduction of side reactions, and is a landmark reagent for synthesis of complex molecules.

[0004] Dimethyl vinyl chlorosilane, also known as chlorodimethylvinylsilane, is a functional organic silane compound with excellent performance, which can be used to synthesize other important functional organic silicon intermediates, can be used to synthesize other functional organic silicon intermediates by using the unsaturated bond Si-CH=CH2 on the silane molecule, and can also be used as an active end-capping agent for producing high-performance silicone oil and silicone rubber materials. In addition, dimethyl vinyl chlorosilane can also be used as a surfactant, a lubricant, a secondary addition agent, a casting agent, a cleaning agent and the like. Dimethyl vinyl chlorosilane has a wide application in the manufacturing of plastic products. In general, dimethyl vinyl chlorosilane is a multifunctional organic silane compound with wide application prospect and economic value.

[0005] The synthesis methods of the above three kinds of chlorosilanes are various, such as direct synthesis method, hydrogenation method, halogenation method, hydrolysis-chlorination method, Grignard reagent method and disproportionation reaction method. However, the existing technical solutions have significant deficiencies in actual application: the traditional chlorosilane preparation process is difficult to improve the product yield while ensuring safety.

[0006] In addition, the chlorinating reagents (such as hydrogen chloride gas, tetrachlorosilane, trimethyl chlorosilane and the like) used in the current chlorination method generally have the following defects: low reaction activity and insufficient selectivity, complex by-product treatment process, hidden dangers in stability and operation safety, and high production cost.

[0007] Iodoethane, commonly known as ethyl iodide, is a colorless and clear heavy liquid in appearance and shape, soluble in ethanol, ether and most organic solvents. Iodoethane plays an important role in alkanes and has quite extensive and very important uses. Iodoethane is an important intermediate in organic synthesis and an important raw material for the synthesis of MO source, used as an ethylating agent, a thyroid tumor treatment drug, a plant growth stimulant, etc. It is used as an auxiliary agent in the pharmaceutical industry and as an analytical reagent, and is also used in organic synthesis, thyroid tumor treatment drugs, plant growth stimulants, etc.

[0008] Iodoethane can also be synthesized in various ways. The traditional method is to use the reaction of alcohol with phosphorus triiodide to generate, however, these reactions generate oxygen H3PO3. Another method is to use hydrogenated acid to crack dialkyl ether, but many ethers are not easy to obtain. Some modern synthesis methods include the reaction of alcohol with iodide in the presence of p-toluenesulfonic acid, excess sodium chloride nucleophilic substitution, and fast reaction of organoborane with iodine in the presence of base. In the prior art, another process uses a chlorinating agent and dimethyl vinyl ethoxy silane as a raw material (such as patent CN118852233A), however, this process has significant drawbacks. In the preparation process of this process, ether is used as a solvent, aluminum chloride is used as a catalyst, ether is extremely volatile, and its vapor is extremely explosive when mixed with air and exposed to fire, which poses a serious safety hazard to the production process. At the same time, aluminum chloride generates a large amount of aluminum-containing waste residue after participating in the reaction, which not only increases the cost of waste treatment, but also pollutes the soil and water if not properly treated, harming the ecological environment. In addition, the steps of separating the solvent and catalyst from the product after the reaction are complicated, which not only leads to low product purification efficiency, but also greatly increases the production cost. There is also a process for preparing iodoethane by reacting diethyl sulfate with an iodine-containing solution (such as patent CN113831213A), but diethyl sulfate is prone to produce some difficult-to-treat sulfur-containing byproducts during the reaction, polluting the environment; and due to the high reactivity and strong toxicity of diethyl sulfate, there is a high safety risk (leakage, explosion) during use, which is easily hydrolyzed in a humid environment to generate toxic gas (sulfur dioxide) that is harmful to the environment, and improper handling can cause environmental pollution.

[0009] With the acceleration of technological progress and industrialization, the market demand for chlorosilane and iodoethane continues to grow, and its pulling effect is increasingly significant. Therefore, it is of great practical significance to carry out production research on chlorosilane and iodoethane, and how to efficiently prepare these two compounds has always been a technical demand in the field. Developing a method for co-producing chlorosilane and iodoethane has become a focus of the industry. SUMMARY

[0010] The purpose of the present application is to provide a method for co-producing chlorosilane and iodoethane to solve the problems in the background art.

[0011] Thionyl chloride is used as chlorinating agent to produce chlorosilane, the by-product is mainly diethyl sulfite, which can be collected to prepare iodoethane with potassium iodide, sodium iodide, etc. as the second product for sale.

[0012] To achieve the above technical purposes, the technical scheme adopted by the present application is as follows:

[0013] Preparation of chlorosilane by using thionyl chloride and tert-butyl dimethyl ethoxysilane (dimethyl vinyl ethoxysilane or tert-butyl diphenyl ethoxysilane)

[0014]

[0015] R = -C (CH3) 3 / -CH = CH2

[0016]

[0017] Preparation of iodoethane by using diethyl sulfite and magnesium iodide

[0018]

[0019] A method for co-producing chlorosilane and iodoethane as shown in the above formula, comprising the following steps:

[0020] S1. Connect the micro-channel reactor inlet ① with infusion pump ① to feed material A, and stop feeding when the material just enters the micro-channel reactor inlet ①;

[0021] S2. Connect the micro-channel reactor inlet ② with infusion pump ② to feed thionyl chloride, and open the infusion pump ① to make material A and thionyl chloride enter the micro-channel reactor at the same time when the material just enters the micro-channel reactor inlet ②;

[0022] S3. Connect the micro-channel reactor outlet to discharge the reaction liquid, and perform rectification on the reaction liquid to obtain chlorosilane and diethyl sulfite;

[0023] S4. Put material C in a reaction container, add water to form a solution, and start stirring and heating; slowly add the diethyl sulfite fraction obtained in step S3; after the addition is completed, react for 4 hours to obtain reaction liquid D;

[0024] S5. Cool the reaction liquid D to room temperature to perform liquid separation, dry the organic phase, and perform rectification to prepare iodoethane.

[0025] In S1, material A is tert-butyl dimethyl ethoxysilane, vinyl dimethyl ethoxysilane or tert-butyl diphenyl ethoxysilane.

[0026] Wherein, the flow rate of the reaction in S1 is determined according to the remaining amount of the material A, the flow rate of the infusion pump 1 is 90-110 ml / min, and the flow rate of the infusion pump 2 in S2 is 20-35 ml / min.

[0027] When the material A is tert-butyl dimethyl ethoxy silane, the optimal flow rate of the infusion pump 1 in S1 is 100-108 ml / min, and the optimal flow rate of the infusion pump 2 in S2 is 26-32 ml / min.

[0028] When the material A is dimethyl vinyl ethoxy silane, the optimal flow rate of the infusion pump 1 in S1 is 95-102 ml / min, and the optimal flow rate of the infusion pump 2 in S2 is 24-28 ml / min.

[0029] When the material A is tert-butyl diphenyl ethoxy silane, the optimal flow rate of the infusion pump 1 in S1 is 96-105 ml / min, and the optimal flow rate of the infusion pump 2 in S2 is 25-30 ml / min.

[0030] Wherein, the temperature of the micro-channel reactor in S1 is controlled at 10-60°C, preferably 40-55°C.

[0031] Wherein, the distillation temperature in S3 is not higher than 165°C.

[0032] Wherein, when the material A is tert-butyl dimethyl ethoxy silane, fraction 1 collected at 122-127°C is tert-butyl dimethyl chlorosilane, and fraction 2 collected at 158-160°C is diethyl sulfite;

[0033] When the material A is dimethyl vinyl ethoxy silane, fraction 1 collected at 78-85°C is dimethyl vinyl chlorosilane, and fraction 2 collected at 158-160°C is diethyl sulfite;

[0034] When the material A is tert-butyl diphenyl ethoxy silane, fraction 1 collected at 158-160°C is diethyl sulfite, and then vacuum distillation is performed under the condition that the vacuum degree is >0.08 MPa, and fraction 2 collected at 125-133°C is tert-butyl diphenyl chlorosilane.

[0035] Wherein, the material C in S4 is potassium iodide, magnesium iodide or sodium iodide, the reaction temperature is 10-100°C, preferably 65-80°C, and the reaction time is determined according to the remaining amount of the raw material.

[0036] Wherein, the distillation temperature in S5 is not higher than 80°C.

[0037] The process flow chart of the above reaction is as shown in Figure 1 .

[0038] Beneficial effects

[0039] 1. In the process of innovation of chemical synthesis, the present application shows distinct technical advantages. On the one hand, the dependence on solvents and catalysts in traditional processes is abandoned, which not only avoids the purification problems caused by solvent residues, effectively simplifies the production process and reduces production costs, but also reduces the potential harm to the environment caused by the use of chemical reagents, in line with the development concept of green chemistry. On the other hand, during the reaction process, chlorosilane and its by-products can be collected in real time. The collected by-products can be used as raw materials for the subsequent preparation of iodoethane, greatly improving the utilization rate of raw materials, turning waste into treasure, extending the value of the industrial chain, and further enhancing the economic benefits of the entire process.

[0040] In the preparation process of chlorosilane, the use of thionyl chloride as a chlorinating agent has significant advantages. With the characteristics of high reaction efficiency, simple product separation and controllable cost, it has become a commonly used chlorinating agent in the field of organic synthesis, especially in the production of pharmaceutical intermediates, pesticides and fine chemicals.

[0041] From the perspective of safety and environmental protection, the by-products of this process have no difficult-to-degrade solid waste, and the environmental treatment difficulty is low; the reaction conditions are mild, without the need for high pressure or strong corrosive reagents, effectively reducing the safety risk of operation. In terms of reaction effect, the purity of chlorosilane prepared can reach ≥99%, without the need for complex purification process, fully suitable for the application scenarios of pharmaceuticals, pesticides and other strict purity requirements.

[0042] In the preparation process of iodoethane, the by-product of chlorosilane, diethyl sulfite, is used as a raw material, which shows excellent comprehensive advantages and is highly consistent with the concept of green chemistry. From the perspective of safety and environmental protection, diethyl sulfite itself has low toxicity, greatly reducing the safety hazards in the production process and making operation and management more convenient. Moreover, the by-products generated after the reaction of this raw material are easy to handle, greatly reducing the potential harm to the environment. In terms of economic cost, using diethyl sulfite as a raw material, the reaction conditions are relatively mild, the requirements for equipment pressure resistance and temperature resistance are low, effectively reducing the investment and long-term operation cost of equipment. In terms of reaction effect, diethyl sulfite has moderate reactivity, which can significantly reduce the occurrence of side reactions during the preparation of iodoethane, not only improving the yield of iodoethane, but also improving the purity of the product. This makes the subsequent separation and purification steps simple, greatly improving the production efficiency.

[0043] The present application reduces the energy consumption and equipment requirements in the production process, the entire production process is continuous, the device is simple and easy to control, and chlorosilane and by-products can be extracted and collected in time, which is especially suitable for large-scale industrial production. It greatly improves the atomic utilization rate and reduces the production cost throughout the process.

[0044] 2. In the preparation process of the present application, the collected by-products can be used to prepare iodoethane with the company's existing products and sold.

[0045] 3. The whole production process is continuous, the device is simple and easy to control, safe, high in product quality and yield, and capable of timely extracting and collecting by-products, and is particularly suitable for large-scale industrial production.

[0046] 4. The process is relatively friendly to the environment, in line with the development concept of green chemistry, reduces pollution to the environment, and reduces environmental pressure in the production process. BRIEF DESCRIPTION OF DRAWINGS

[0047] Figure 1 The process flow chart for co-production of chlorosilane and iodoethane according to the present application.

[0048] Figure 2 The process flow chart for preparation of chlorosilane according to the present application. DETAILED DESCRIPTION

[0049] The present application will be further described by the following examples, it should be correctly understood that: the examples of the present application are only used to illustrate the present application, but not limit the present application, so, the simple improvement of the present application under the method of the present application is within the scope of the present application.

[0050] The technical effects of the method for co-production of chlorosilane and iodoethane according to the present application will be further described by listing specific examples.

[0051] Example 1

[0052] Take 439.37g of tert-butyl dimethyl ethoxysilane, open the infusion pump ① to fill the pipeline but not enter the micro-channel reactor; take 163.18g of chlorosulfoxide, open the infusion pump ② to fill the pipeline but not enter the micro-channel reactor, at the same time, open the infusion pump ① and the infusion pump ②, the flow rate of the infusion pump ① is 105ml / min, the flow rate of the infusion pump ② is 30ml / min, and the reaction liquid is collected at the outlet of the micro-channel reactor; the reaction liquid is subjected to rectification, fraction 1 (tert-butyl dimethyl chlorosilane) of 122-127℃ is collected 372.53g, fraction 2 (diethyl sulfite) of 158-160℃ is collected 180.56g, and the purity of tert-butyl dimethyl chlorosilane is detected to be more than 99%.

[0053] Example 2

[0054] Take 780.43 g of t-butyl diphenyl ethoxy silane, open infusion pump 1 to fill the pipeline but not into the micro-channel reactor; take 163.18 g of chlorosulfoxide, open infusion pump 2 to fill the pipeline but not into the micro-channel reactor, at the same time open infusion pump 1 and infusion pump 2, the flow rate of infusion pump 1 is 100 ml / min, the flow rate of infusion pump 2 is 28 ml / min, collect the reaction liquid at the outlet of the micro-channel reactor; carry out rectification on the reaction liquid, collect fraction 1 (diethyl sulfite) 181.03 g at 158-160 ℃, then carry out rectification under reduced pressure, keep the vacuum degree > 0.08 MPa, collect fraction 2 (t-butyl diphenyl chlorosilane) 671.06 g at 125-133 ℃, and detect the purity of t-butyl diphenyl chlorosilane to be more than 99%.

[0055] Example 3

[0056] Take 780.43 g of t-butyl diphenyl ethoxy silane, open infusion pump 1 to fill the pipeline but not into the micro-channel reactor; take 163.18 g of chlorosulfoxide, open infusion pump 2 to fill the pipeline but not into the micro-channel reactor, at the same time open infusion pump 1 and infusion pump 2, the flow rate of infusion pump 1 is 100 ml / min, the flow rate of infusion pump 2 is 28 ml / min, collect the reaction liquid at the outlet of the micro-channel reactor; carry out rectification on the reaction liquid, collect fraction 1 (diethyl sulfite) 181.03 g at 158-160 ℃, then carry out rectification under reduced pressure, keep the vacuum degree > 0.08 MPa, collect fraction 2 (t-butyl diphenyl chlorosilane) 671.06 g at 125-133 ℃, and detect the purity of t-butyl diphenyl chlorosilane to be more than 99%.

[0057] Example 4

[0058] Put 181.20 g of magnesium iodide into a reaction container, add 100.00 g of water to form a solution, open the stirring and heat to 70 ℃; slowly drop 180.00 g of diethyl sulfite prepared in Example 1; after the dropping is completed, react for 4 h; cool the reaction liquid to room temperature to carry out liquid-liquid separation, and transfer the organic phase into a reaction bottle; slowly increase the temperature of the bottom kettle to carry out rectification on the organic phase, and collect fraction 1 (iodoethane) 181.70 g at 71-75 ℃; after the collection is completed, add 20.00 g of zeolite molecular sieve into the fraction, stand for 24 h, and then filter to obtain iodoethane 180.53 g, the content of which is more than 99.9%, and the moisture content is 96 ppm.

[0059] Example 5

[0060] Put 216.30g of potassium iodide into a reaction vessel, add 100.00g of water to form a solution, start stirring, and heat to 70℃; slowly add 180.00g of diethyl sulfite prepared in Example 2; after the addition is completed, react for 4h; cool the reaction liquid to room temperature and separate, transfer the organic phase into a reaction bottle; slowly increase the temperature of the bottom kettle, and distill the organic phase, collect 177.03g of a fraction (iodoethane) at 71-75℃; after the collection is completed, add 20.00g of zeolite molecular sieve to the fraction, stand for 24h, and filter to obtain 176.87g of iodoethane, with a content of more than 99.9% and a moisture content of 90ppm.

[0061] Example 6

[0062] Put 195.31g of sodium iodide into a reaction vessel, add 100.00g of water to form a solution, start stirring, and heat to 70℃; slowly add 180.00g of diethyl sulfite prepared in Example 3; after the addition is completed, react for 4h; cool the reaction liquid to room temperature and separate, transfer the organic phase into a reaction bottle; slowly increase the temperature of the bottom kettle, and distill the organic phase, collect 180.53g of a fraction (iodoethane) at 71-75℃; after the collection is completed, add 20.00g of zeolite molecular sieve to the fraction, stand for 24h, and filter to obtain 180.05g of iodoethane, with a content of more than 99.9% and a moisture content of 94ppm.

[0063] Finally, it should be noted that the above-described examples only express several embodiments of the present application, and are not intended to limit the present application; for those of ordinary skill in the art, any modifications, equivalent replacements, improvements, etc. made without departing from the concept of the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A process for the co-production of chlorosilanes and iodoethane, characterized in that, The method comprises the following steps: S1. connecting the micro-channel reactor inlet ① with infusion pump ① to feed material A, and stopping the feeding when the material A just enters the micro-channel reactor inlet ①; the material A is t-butyldimethylethoxysilane, dimethylethoxysilane or t-butyldiphenylethoxysilane; S2. connecting the micro-channel reactor inlet ② with infusion pump ② to feed sulfurous chloride, and opening the infusion pump ① to make the material A and the sulfurous chloride enter the micro-channel reactor at the same time when the sulfurous chloride just enters the micro-channel reactor inlet ②; S3. connecting the micro-channel reactor outlet with the reaction liquid, and distilling the reaction liquid to obtain chlorosilane and diethyl sulfite; S4. placing material C in a reaction container, adding water to form a solution, and then stirring and heating; slowly adding the diethyl sulfite prepared in step S3; after the addition is completed, reacting for 4 hours to obtain reaction liquid D; the material C is potassium iodide, magnesium iodide or sodium iodide; S5. cooling the reaction liquid D to room temperature, separating the organic phase, drying the organic phase, and then distilling to prepare iodoethane.

2. The method of claim 1, wherein, The temperature of the micro-channel reactor is controlled at 10-60℃.

3. The method of claim 2, wherein, The temperature of the micro-channel reactor is controlled at 40-55℃.

4. The method of claim 1, wherein, When the material A is t-butyldimethylethoxysilane, the flow rate of the infusion pump ① in S1 is 100-108 ml / min, and the flow rate of the infusion pump ② in S2 is 26-32 ml / min; when the material A is dimethylethoxysilane, the flow rate of the infusion pump ① in S1 is 95-102 ml / min, and the flow rate of the infusion pump ② in S2 is 24-28 ml / min; when the material A is t-butyldiphenylethoxysilane, the flow rate of the infusion pump ① in S1 is 96-105 ml / min, and the flow rate of the infusion pump ② in S2 is 25-30 ml / min.

5. The method of claim 1, wherein, The distillation temperature in S3 is not higher than 165℃.

6. The method of claim 1, wherein, When the material A is t-butyldimethylethoxysilane in S3, fraction 1 collected at 122-127℃ is t-butyldimethylchlorosilane, and fraction 2 collected at 158-160℃ is diethyl sulfite; when the material A is dimethylethoxysilane, fraction 1 collected at 78-85℃ is dimethylchlorosilane, and fraction 2 collected at 158-160℃ is diethyl sulfite; when the material A is t-butyldiphenylethoxysilane, fraction 1 collected at 158-160℃ is diethyl sulfite, and then vacuum distillation is performed under the condition that the vacuum degree is greater than 0.08 MPa, and fraction 2 collected at 125-133℃ is t-butyldiphenylchlorosilane.

7. The method of claim 1, wherein, The reaction temperature in S4 is 10-100℃.

8. The method of claim 1, wherein, The reaction temperature in S4 is 65-80℃.

9. The method of claim 1, wherein, The distillation temperature in S5 is not higher than 80℃.

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