阅读说明：本技术 一种甲基苯基亚砜的制备方法 (Preparation method of methyl phenyl sulfoxide ) 是由 余焓 陶朝富 王爱萍 谢雅 常亚林 于 2021-01-08 设计创作，主要内容包括：本发明涉及一种甲基苯基亚砜的制备方法,该方法为：以多金属氧酸盐为催化剂,放进反应容器中,将有机溶剂和甲基苯基醚依次加入容器,最后加入氧化剂,加热搅拌反应后,分离得到甲基苯基亚砜,反应结束后可以滤出多金属氧酸盐,处理后进行回收,将回收的多金属氧酸盐再用于甲基苯基醚的氧化反应。与现有技术相比,本发明氧源为空气或者氧气,具有绿色环保不含氯杂质,合成路线短,成本低等优点。(The invention relates to a preparation method of methyl phenyl sulfoxide, which comprises the following steps: polyoxometallate is used as a catalyst and is put into a reaction container, an organic solvent and methyl phenyl ether are sequentially added into the container, finally, an oxidant is added, after heating and stirring reaction, methyl phenyl sulfoxide is obtained through separation, the polyoxometallate can be filtered out after the reaction is finished, the polyoxometallate is recovered after treatment, and the recovered polyoxometallate is reused for the oxidation reaction of the methyl phenyl ether. Compared with the prior art, the oxygen source is air or oxygen, and the method has the advantages of environmental protection, no chlorine impurity, short synthetic route, low cost and the like.)

1. A preparation method of methyl phenyl sulfoxide is characterized in that the method comprises the following steps: polyoxometallate is used as a catalyst and is put into a reaction container, an organic solvent and methyl phenyl ether are sequentially added into the container, finally, an oxidant is added, and after heating, stirring and reaction, methyl phenyl sulfoxide is obtained by separation.

2. The method of claim 1, wherein the polyoxometallate is Keggin, Dawson, Silverton, Waugh, Lindquist or Anderson.

3. The method of claim 1, wherein the catalyst is an Anderson type or Lindquist type polyoxometalate centered on Fe, Al, Cr, Ni, Mn, Cu or Co.

4. The method according to claim 1, wherein the catalyst is added in an amount of 1.0 to 5.0 mol%.

5. The method of claim 1, wherein the oxidizing agent comprises hydrogen peroxide, air or oxygen.

6. The method according to claim 5, wherein the oxidizing agent is oxygen.

7. The method of claim 1, wherein the organic solvent comprises acetonitrile, methyl butyl ether, ethanol or benzene.

8. The method for preparing methyl phenyl sulfoxide according to claim 1, wherein the heating temperature is 50-80 ℃, and the reaction time is 12-24 h.

9. The method for preparing methyl phenyl sulfoxide according to claim 1, wherein the heating temperature is 80 ℃, and the reaction time is 24 h.

10. The method according to claim 1, wherein the polyoxometallate is filtered out after the reaction is completed, and the polyoxometallate is recovered after treatment, and the recovered polyoxometallate is reused for the oxidation reaction of the methyl phenyl ether.

Technical Field

The invention relates to the technical field of catalysis, in particular to a preparation method of methyl phenyl sulfoxide.

Background

The sulfoxide is not only a solvent and an extracting agent commonly used in organic synthesis experiments, but also widely applied to the synthesis of various medicines, and is an important intermediate of medicines, pesticides and expensive materials. The selection of a catalyst capable of efficiently oxidizing thioether into sulfoxide is always a hot point in the field of synthesis, and the currently commonly used catalysts mainly comprise hydrogen peroxide, metal compounds and halogen compounds.

At present, a method for generating methyl phenyl sulfoxide singly by catalytic oxidation of methyl phenyl ether, which is green and environment-friendly, does not exist. The catalysts commonly used in the prior art are mainly hydrogen peroxide, metal compounds and halogen compounds. The method for preparing the methyl sulfoxide compound by using ethanol as a solvent and hydrogen peroxide as an oxidant only needs 4 hours at the fastest speed, but needs to prepare an acid functionalized magnetic nanoparticle-DSA @ MNPs at the early stage, is complex and time-consuming in process, and is not suitable for scientific research requirements of multiple reaction steps, mass production or short time and high efficiency; using chromium or copper with magnetic Fe₃O₄The metal composite material prepared by compounding the nanoparticles is used as a catalyst, although the material has cyclic regeneration, the toxicity of transition metal is high, and slight residue after entering a human body can cause great damage; the method for oxidizing thioether into sulfoxide by using NaOBr sodium hypobromite is also used, but the method has many side reactions and low yield and is not suitable for preparing sulfoxide compounds. In addition, the use of stoichiometric amounts of inorganic oxidizing agents generates a large amount of inorganic waste, causing serious environmental pollution.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provide the preparation method of the methyl phenyl sulfoxide, which has the advantages of air or oxygen as an oxygen source, environmental friendliness, no chlorine impurity, short synthetic route and low cost.

The purpose of the invention can be realized by the following technical scheme:

a preparation method of methyl phenyl sulfoxide comprises the following steps: the method comprises the following steps of putting polyoxometallate serving as a catalyst into a reaction container, sequentially adding an organic solvent and methyl phenyl ether into the container, finally adding an oxidant, heating, stirring, reacting, and separating to obtain methyl phenyl sulfoxide, wherein the reaction formula is as follows:

further, the polyoxometallate is Keggin type, Dawson type, Silverton type, Waugh type, Lindquist type or Anderson type.

Furthermore, the catalyst is an Anderson type or Lindquist type polyoxometallate taking Fe, Al, Cr, Ni, Mn, Cu or Co as the center.

Further, the amount of the catalyst added is 1.0 to 5.0 mol%, preferably 1.0 mol%. The mol% is relative to the amount of the methyl phenyl ether, and the amount of the catalyst to be added is 0.01 to 0.05mmol, for example, 1mmol of the methyl phenyl ether.

Further, the oxidizing agent comprises hydrogen peroxide, air or oxygen, preferably oxygen at a pressure of 1 atm.

Further, the organic solvent comprises acetonitrile, methyl butyl ether, ethanol or benzene, preferably ethanol.

Further, the heating temperature is 50-80 ℃, and the reaction time is 12-24 h.

Further, the heating temperature is 80 ℃, and the reaction time is 24 h.

Further, filtering out polyoxometallate after the reaction is finished, treating and recovering the polyoxometallate, and reusing the recovered polyoxometallate for the oxidation reaction of the methyl phenyl ether.

Compared with the prior art, the method has the characteristics of simple preparation, high product yield, no three wastes, low production cost and the like, and is an environment-friendly method for preparing the methyl phenyl sulfoxide with high atom economy. The catalyst is a novel catalyst, namely polyoxometallate (heteropoly acid), can be recycled for multiple times after simple treatment, does not need to add acid in the reaction process, and is very beneficial to industrial production, so the method has potential application prospect.

Drawings

FIG. 1 is the NMR carbon spectrum of methyl phenyl sulfoxide obtained by the present invention¹H NMR(CDCl₃)；

FIG. 2 shows the NMR spectrum of methyl phenyl sulfoxide obtained by the present invention¹³C NMR(CDCl₃)

Detailed Description

For further details of the present invention, several embodiments are given below, which mainly take the example of the Anderson-type polyoxometalate catalyst with different metal atoms as the center. However, the present invention is not limited to these examples.

Example 1

0.1242g of methyl phenyl ether, 0.1-5.0 mol% of Anderson type polyoxometallate taking Fe as a central metal and 2.0-6.0mL of solvent ethanol are put into a dry reaction tube, an oxygen balloon is sleeved on the reaction tube, the reaction temperature is controlled at 50-80 ℃, the reaction is stopped after 24 hours of heat preservation reaction, the reaction is cooled to room temperature, a sample is prepared and is detected by GC-MS, and the GC-MS result shows that the conversion rate of a reaction substrate is 95%. And performing nuclear magnetic test after separation and purification, and verifying that the product is methyl phenyl sulfoxide from the obtained hydrogen spectrum and carbon spectrum data.

Example 2

0.1242g of methyl phenyl ether, 0.1-5.0 mol% of Anderson type polyoxometallate taking Al as a central metal and 2.0-6.0mL of solvent ethanol are put into a dry reaction tube, an oxygen balloon is sleeved on the reaction tube, the reaction temperature is controlled to be 50-80 ℃, the reaction is stopped after 24 hours of heat preservation reaction, the reaction is cooled to room temperature, a sample is prepared and is detected by GC-MS, and the GC-MS result shows that the conversion rate of a reaction substrate is 91%. And performing nuclear magnetic test after separation and purification, and verifying that the product is methyl phenyl sulfoxide from the obtained hydrogen spectrum and carbon spectrum data.

Example 3

0.1242g of methyl phenyl ether, 0.1-5.0 mol% of Anderson type polyoxometallate taking Cr as a central metal and 2.0-6.0mL of solvent ethanol are put into a dry reaction tube, an oxygen balloon is sleeved on the reaction tube, the reaction temperature is controlled to be 50-80 ℃, the reaction is stopped after 24 hours of heat preservation reaction, the reaction is cooled to room temperature, a sample is prepared and is detected by GC-MS, and the GC-MS result shows that the conversion rate of a reaction substrate is 89%. And performing nuclear magnetic test after separation and purification, and verifying that the product is methyl phenyl sulfoxide from the obtained hydrogen spectrum and carbon spectrum data.

Example 4

0.1242g of methyl phenyl ether, 0.1-5.0 mol% of Anderson type polyoxometallate taking Ni as central metal and 2.0-6.0mL of solvent ethanol are put into a dry reaction tube, an oxygen balloon is sleeved on the reaction tube, the reaction temperature is controlled at 50-80 ℃, the reaction is stopped after 24 hours of heat preservation reaction, the reaction is cooled to room temperature, a sample is prepared and is detected by GC-MS, and the GC-MS result shows that the conversion rate of a reaction substrate is 93%. And performing nuclear magnetic test after separation and purification, and verifying that the product is methyl phenyl sulfoxide from the obtained hydrogen spectrum and carbon spectrum data.

Example 5

0.1242g of methyl phenyl ether, 0.1-5.0 mol% of Anderson type polyoxometallate taking Mn as a central metal and 2.0-6.0mL of solvent ethanol are put into a dry reaction tube, an oxygen balloon is sleeved on the reaction tube, the reaction temperature is controlled to be 50-80 ℃, the reaction is stopped after 24 hours of heat preservation reaction, the reaction is cooled to room temperature, a sample is prepared and is detected by GC-MS, and the GC-MS result shows that the conversion rate of a reaction substrate is 92%. And performing nuclear magnetic test after separation and purification, and verifying that the product is methyl phenyl sulfoxide from the obtained hydrogen spectrum and carbon spectrum data.

Example 6

0.1242g of methyl phenyl ether, 0.1-5.0 mol% of Anderson type polyoxometallate taking Co as central metal and 2.0-6.0mL of solvent ethanol are put into a dry reaction tube, an oxygen balloon is sleeved on the reaction tube, the reaction temperature is controlled at 50-80 ℃, the reaction is stopped after 24 hours of heat preservation reaction, the reaction is cooled to room temperature, a sample is prepared and is detected by GC-MS, and the GC-MS result shows that the conversion rate of a reaction substrate is 90%. And performing nuclear magnetic test after separation and purification, and verifying that the product is methyl phenyl sulfoxide from the obtained hydrogen spectrum and carbon spectrum data.

Example 7

0.1242g of methyl phenyl ether, 0.1-5.0 mol% of Anderson type polyoxometallate taking Cu as a central metal and 2.0-6.0mL of solvent ethanol are put into a dry reaction tube, an oxygen balloon is sleeved on the reaction tube, the reaction temperature is controlled to be 50-80 ℃, the reaction is stopped after 24 hours of heat preservation reaction, the reaction is cooled to room temperature, a sample is prepared and is subjected to GC-MS detection, and the GC-MS result shows that the conversion rate of a reaction substrate is 91%. And performing nuclear magnetic test after separation and purification, and verifying that the product is methyl phenyl sulfoxide from the obtained hydrogen spectrum and carbon spectrum data. And (4) treating and recycling the catalyst after reaction.

Example 8

The reaction procedure was the same as in example 1, except that the catalyst was used for the 1 st use after recovery, the conversion of methylphenyl ether was more than 95% by GC-MS analysis, the product was isolated and purified, and the nuclear magnetism was confirmed to be methylphenyl sulfoxide, with a yield of 95%.

Example 9

The reaction procedure was the same as example 1, except that the catalyst was used for the 2 nd use after recovery, the conversion of methylphenyl ether was greater than 95% by GC-MS analysis, the product was isolated and purified, and the nuclear magnetism was confirmed to be methylphenyl sulfoxide.

Example 10

The reaction procedure was the same as in example 1, except that the catalyst was used 3 rd time after recovery, the conversion of methylphenyl ether was 90% by GC-MS analysis, the product was isolated and purified, and nuclear magnetic resonance was confirmed to be methylphenyl sulfoxide.

Example 11

The reaction procedure was the same as in example 1, except that the catalyst was used 4 th time after recovery, the conversion of methylphenyl ether was 83% by GC-MS analysis, the product was isolated and purified, and it was confirmed as methylphenyl sulfoxide by nuclear magnetism.

Example 12

The procedure is as in example 1, except that 4.8g (0.5 mol%) of 4-butylammonium bromide is added to the reaction, the conversion of the methylphenyl ether is less than 80% by GC-MS analysis, the catalyst solid is obtained by filtration, washed and dried, collected for reuse, and the filtrate is separated and purified to obtain a pale yellow product which is confirmed to be methylphenyl sulfoxide by nuclear magnetism.

Example 13

The reaction procedure is as in example 1, but with the difference that the catalyst used is 0.1 to 5.0 mol% of the Lindquist type [ (C)₄H₉)₄N]₃[V₁₀O₂₈H₃]GC-MS analysis showed that the conversion of methylphenyl ether was 73%, separation and purification gave the product which was confirmed to be methylphenyl sulfoxide by nuclear magnetism.

Example 14

The reaction procedure is as in example 1, but with the exception that from 0.1 to 5.0 mol% of Lindquist is used as catalystType H₅[PMo₁₀V₂O₄₀]GC-MS analysis showed that the conversion of methylphenyl ether was 93%, separation and purification gave the product, which was confirmed to be methylphenyl sulfoxide by nuclear magnetism.

The foregoing is directed to preferred embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow. However, any simple modification, equivalent change and modification of the above embodiments according to the technical essence of the present invention are within the protection scope of the technical solution of the present invention.