Method for preparing deuterated pyrene by hydrogen-deuterium exchange method

Abstract

The invention belongs to the technical field of organic compound preparation, and particularly relates to a method for preparing deuterated pyrene by a hydrogen-deuterium exchange method, which comprises the following steps: pyrene, heavy water and a catalyst are mixed in a reaction kettle for hydrogen-deuterium exchange reaction; the catalyst is an aluminum oxide supported palladium catalyst. According to the preparation method, the deuteration rate of a single hydrogen-deuterium exchange reaction is high, meanwhile, byproducts are few, a deuterated pyrene crude product with the purity being 90% or above can be obtained through simple extraction, column chromatography is not needed, and purification is convenient and rapid.

Description

Technical Field

[0001] The present invention belongs to the technical field of organic compound preparation, and particularly relates to a method for preparing deuterated pyrene by hydrogen-deuterium exchange method. Background Art

[0002] Pyrene is an important raw material in organic synthesis. 1,4,5,8-naphthalenetetracarboxylic acid can be prepared through an oxidation reaction, and this substance can be used in the preparation of dyes, synthetic resins, disperse dyes, and engineering plastics. Pyrene can be used to prepare vat dye brilliant orange GR and many other dyes through an acylation reaction. These dyes have extensive applications in industries such as textiles, leather, and paper making. Pyrene can also be used to manufacture pesticides and fungicides, providing effective prevention and control means for agricultural production. Due to its strong fluorescence and the property of emitting light when voltage is applied, pyrene is widely used in the research of electroluminescence. And pyrene can be polymerized to obtain conductive polypyrene, which is used in the manufacture of electronic devices. In addition, pyrene can also be used to manufacture products such as plasticizers.

[0003] Compared with ordinary pyrene, deuterated pyrene (pyrene-D10) has only hydrogen atoms replaced by deuterium atoms in its structure, so its chemical properties are almost the same. In addition to the above applications, it can also be used as a reference substance to determine the signal intensity and chemical shift of samples. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for preparing deuterated pyrene by hydrogen-deuterium exchange method, which has a high deuteration rate in a single hydrogen-deuterium exchange reaction, few by-products at the same time, and the crude deuterated pyrene with a purity of more than 90% can be obtained by simple extraction without column chromatography, and the purification is convenient and fast.

[0005] Specifically, the present invention provides the following technical solutions:

[0006] A method for preparing deuterated pyrene by hydrogen-deuterium exchange method, comprising the following steps:

[0007] 1) Mix pyrene, heavy water and a catalyst in a reaction kettle and carry out a hydrogen-deuterium exchange reaction;

[0008] The catalyst is palladium catalyst supported on aluminum oxide.

[0009] Preferably, in step 1), the reaction time of the hydrogen-deuterium exchange reaction is 24 h or more. It is found that when the reaction time is less than 24 h, the deuteration rate decreases significantly.

[0010] Preferably, in step 1), the reaction temperature of the hydrogen-deuterium exchange reaction is 180-200 °C.

[0011] More preferably, in step 1), the reaction temperature of the hydrogen-deuterium exchange reaction is 190 °C. It is found that when the reaction is carried out at 190 °C, the deuteration rate of the product is higher.

[0012] Preferably, in step 1), the mass ratio of pyrene, heavy water and the catalyst is 2:(80-110):(2-3).

[0013] Preferably, in step 1), the palladium loading in the catalyst is 0.5 wt%.

[0014] Preferably, it further includes the step of further treating the reaction solution obtained from the hydrogen-deuterium exchange reaction:

[0015] 2) Cool the reaction solution after the hydrogen-deuterium exchange reaction to room temperature, add an organic solvent for extraction, collect the organic layer, and then remove the organic solvent by vacuum distillation to obtain a crude product of deuterated pyrene;

[0016] 3) Pulp and purify the crude product of deuterated pyrene in ethanol, and filter and dry it to obtain a deuterated pyrene product.

[0017] More preferably, in step 2), the organic solvent is selected from at least one of ethanol, ethyl acetate, and dichloromethane.

[0018] The beneficial effects of the present invention are at least as follows:

[0019] 1) The method for preparing deuterated pyrene by the hydrogen-deuterium exchange method provided by the present invention uses heavy water as the deuterium source and solvent, and Pd / Al2O3 as the catalyst. The yield of the prepared deuterated pyrene is 50-60%, and the deuteration rate is above 92%;

[0020] 2) The method for preparing deuterated pyrene by the hydrogen-deuterium exchange method provided by the present invention has few by-products. A crude product of deuterated pyrene with a purity above 90% can be obtained by simple extraction without column chromatography, and the purification is convenient and fast;

[0021] 3) The method for preparing deuterated pyrene by the hydrogen-deuterium exchange method provided by the present invention can achieve a deuteration rate of above 98% for the product by optimizing the reaction time, reaction temperature and dosage ratio;

[0022] 4) The method for preparing deuterated pyrene by the hydrogen-deuterium exchange method provided by the present invention can increase the purity to above 98% by pulping and purifying the crude product of deuterated pyrene in ethanol. Description of the Drawings

[0023] Figure 1 It is a process schematic diagram of the method for preparing deuterated pyrene by the hydrogen-deuterium exchange method provided by the present invention.

[0024] Figure 2 It is the NMR spectrum of the deuterated pyrene product prepared in Example 8;

[0025] Figure 3 It is the liquid phase spectrum of the deuterated pyrene product prepared in Example 8;

[0026] Figure 4The gas chromatogram-mass spectrum of the deuterated pyrene product prepared in Example 8. Detailed implementation manners

[0027] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. The following embodiments are used to illustrate the present invention, but are not used to limit the scope of the present invention. For those without specific technical or conditions noted in the embodiments, the techniques or conditions described in the literature in the art or according to the product specifications are followed.

[0028] Examples 1-8

[0029] Examples 1-8 provide a method for preparing deuterated pyrene by the hydrogen-deuterium exchange method, which can be partially referred to Figure 1 , and the specific steps are as follows:

[0030] 1) Pyrene, heavy water (deuterium substitution rate above 99.5%) and Pd / Al2O3 (Xi'an Kaili New Materials Co., Ltd., Pd loading of 0.5 wt) are added to a reaction kettle for hydrogen-deuterium exchange reaction;

[0031] 2) The reaction solution after the hydrogen-deuterium exchange reaction is cooled to room temperature, extracted with an equal volume of dichloromethane, the organic layer is collected, and then the organic solvent is removed to obtain a crude deuterated pyrene product (purity above 90%);

[0032] 3) The crude deuterated pyrene product is added to ethanol for pulping purification (heating under reflux for 1 hour), filtered while hot, and the filter cake is dried to obtain a deuterated pyrene product (yield of 50-60%, purity above 98%).

[0033] The raw material ratios, reaction times, temperatures and deuterated pyrene product data used in Examples 1-8 are shown in Table 1 below. Figure 2 The nuclear magnetic spectrum of the deuterated pyrene product prepared in Example 8; Figure 3 The liquid chromatogram of the deuterated pyrene product prepared in Example 8; Figure 4 The gas chromatogram-mass spectrum of the deuterated pyrene product prepared in Example 8.

[0034] Table 1

[0035]

[0036] As can be seen from Table 1, in Example 1, when the dosage ratio of pyrene, heavy water and catalyst is 1:40:1, the reaction time is 12 h, and the deuterium substitution rate of deuterated pyrene is 92.3%. In Example 2, when the catalyst is not added, the deuterium substitution rate drops to 85.6%. In Example 5, when the reaction time is increased to 24 h, the deuterium substitution rate increases to 98.2%. In Example 6, when the temperature is reduced to 180 °C, the deuterium substitution rate drops below 98%. In Example 8, when the dosage of heavy water is increased to a ratio of 1:55, the deuterium substitution rate does not increase significantly.

[0037] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for preparing deuterated pyrene by hydrogen-deuterium exchange method, which is characterized in that, It includes the following steps: 1) Mix pyrene, heavy water and a catalyst in a reaction kettle and carry out a hydrogen-deuterium exchange reaction; The catalyst is a palladium catalyst supported on aluminum oxide.

2. The method for preparing deuterated pyrene by the hydrogen-deuterium exchange method according to claim 1, characterized in that, In step 1), the reaction time of the hydrogen-deuterium exchange reaction is 24 h or more.

3. The method for preparing deuterated pyrene by the hydrogen-deuterium exchange method according to claim 1, characterized in that, In step 1), the reaction temperature of the hydrogen-deuterium exchange reaction is 180 - 200 °C.

4. The method for preparing deuterated pyrene by the hydrogen-deuterium exchange method according to claim 3, wherein In step 1), the reaction temperature of the hydrogen-deuterium exchange reaction is 190 °C.

5. The method for preparing deuterated pyrene by the hydrogen-deuterium exchange method according to claim 1, wherein In step 1), the mass ratio of the amounts of pyrene, heavy water and the catalyst is 2:(80 - 110):(2 - 3).

6. The method for preparing deuterated pyrene by the hydrogen-deuterium exchange method according to claim 1, wherein In step 1), the loading amount of palladium in the catalyst is 0.5 wt%.

7. The method for preparing deuterated pyrene by the hydrogen-deuterium exchange method according to any one of claims 1-6, characterized in that, It further includes the step of further treating the reaction solution obtained from the hydrogen-deuterium exchange reaction: 2) Cool the reaction solution after the hydrogen-deuterium exchange reaction to room temperature, add an organic solvent for extraction, collect the organic layer, and then remove the organic solvent to obtain a crude product of deuterated pyrene; 3) Pulp and purify the crude product of deuterated pyrene in ethanol, filter and dry it to obtain a deuterated pyrene product.

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