A method for preparing deuterated 9-bromoanthracene

Abstract

The present application relates to a kind of preparation of deuterated 9-bromoanthracene method, wherein the preparation method includes according to the following steps is reacted: (1) dichloromethane, deuterated anthracene is mixed in reactor;(2) bromo succinimide NBS is added;(3) reduced pressure distillation;(4) separation and purification are obtained.

Description

A method for preparing deuterated 9-bromoanthracene Technical Field

[0001] This invention belongs to the field of chemical engineering and relates to a method for preparing deuterated 9-bromoanthracene. Background Technology

[0002] 9-Bromoanthracene is a high-performance fluorescent and phosphorescent luminescent material widely used in optics, cosmetics, electronics, semiconductors, and electroluminescent materials. Deuterated 9-Bromoanthracene is currently an emerging basic raw material mainly used in the OLED field. As an intermediate in the synthesis of blue luminescent materials, it exhibits good thermal stability and color purity, and has a longer lifespan compared to ordinary materials.

[0003] Currently, most methods for synthesizing 9-bromoanthracene use highly corrosive substances such as liquid bromine (bromine), hydrogen bromide, and dimethyl sulfide bromide as bromine sources, which have drawbacks such as poor reaction controllability, strong corrosivity, and serious environmental pollution. The synthesis of common 9-bromoanthracene mostly uses bromosuccinimide as the bromine source, and some patents also use bromide salts and oxidants to prepare common 9-bromoanthracene (CN110860259A).

[0004] Based on the process for synthesizing ordinary 9-bromoanthracene, the synthesis process of deuterated 9-bromoanthracene was further studied. Through a large number of experiments, it was verified that the content of deuterated 9-bromoanthracene was the highest when using bromosuccinimide. The selectivity of deuterated 9-bromoanthracene was reduced when using liquid bromine reaction, which would increase the content of the byproduct deuterated 9-10 dibromoanthracene.

[0005] Because deuterated anthracene exhibits high reactivity at its 9 and 10 positions, its selective substitution of the bromine source during bromination is relatively weak. Different bromine sources and feed rates result in varying amounts of deuterated 9-bromoanthracene and deuterated 9,10-dibromoanthracene. Faster feed rates and higher temperatures lead to higher levels of the byproduct deuterated 9,10-dibromoanthracene. To synthesize deuterated 9-bromoanthracene with high conversion rates, it is necessary to reduce the content of deuterated 9,10-dibromoanthracene, requiring careful control of the reaction temperature, bromine source selection, and feed rate. Summary of the Invention

[0006] In view of this, in order to avoid the problem that excessive bromine source content leads to an increase in the content of the byproduct deuterated 9,10-dibromoanthracene, which in turn makes the separation of the main product deuterated 9-bromoanthracene from the byproduct 9,10-dibromoanthracene difficult, this invention, after extensive experimental verification, utilizes the moderately active bromine source bromosuccinimide (NBS). By adjusting the NBS feed rate and temperature, the content of the main product deuterated 9-bromoanthracene can unexpectedly reach over 97%.

[0007] Specifically, in a first aspect, the present invention provides a method for preparing deuterated 9-bromoanthracene, wherein the preparation method comprises carrying out a reaction according to the following steps:

[0008] (1) Mix dichloromethane and deuterated anthracene in a reactor;

[0009] (2) Add brominated succinimide NBS;

[0010] (3) Vacuum distillation;

[0011] (4) The product is obtained by separation and purification.

[0012] In one embodiment, the reactor is a stirred bed or a reaction vessel equipped with mechanical stirring.

[0013] In one embodiment, in step (1), the mass-to-volume ratio of dichloromethane to deuterated anthracene is 70-120 g / L, preferably 80-110 g / L, and most preferably 90-100 g / L.

[0014] In one implementation, NBS is added in step (2) via a feeder.

[0015] In one embodiment, the vacuum distillation in step (3) includes adding deionized water to form a pulp, filtering, vacuum drying, and removing the solvent dichloromethane.

[0016] In one embodiment, the mass of NBS added in step (2) is 400-600 g, preferably 450-550 g, and most preferably 500-520 g.

[0017] In one embodiment, the feeding time for the step is 1-30 hours, preferably 3-25 hours, and most preferably 5-20 hours.

[0018] In one embodiment, the feeding rate is 10-280 g / h, preferably 13-48 g / h, and most preferably 17-24 g / h.

[0019] In one embodiment, the reaction temperature is 16-44°C, preferably 18-42°C, and most preferably 20-40°C.

[0020] The superior technical effects of the preparation method described in this invention are mainly in the following aspects:

[0021] 1. By adjusting the NBS feed rate and temperature, crude deuterated 9-bromoanthracene with a purity of 95%-97% was prepared. After column chromatography separation and purification, the purity and deuteration rate were both above 99%.

[0022] 2. The method of the present invention is simple to operate, and the interference of the by-product 9,10-dibromoanthracene can be eliminated to the greatest extent by precisely controlling the feed rate and temperature.

[0023] 3. The first step of product purification uses a safe and simple method: vacuum distillation to remove the solvent, followed by slurrying and filtration with deionized water. The second post-treatment step uses easily recoverable methanol as the solvent for recrystallization, with petroleum ether as the eluent, thus reducing the cost of industrial production. Detailed Implementation

[0024] This invention utilizes a conventional method for synthesizing 9-bromoanthracene, reacting bromosuccinimide with deuterated anthracene (both with purity and deuteration rate exceeding 99%) to prepare deuterated 9-bromoanthracene. The feed rate of bromosuccinimide and the reaction temperature were optimized during the preparation process, yielding crude deuterated 9-bromoanthracene with a purity of 95%-97%. Column chromatography purification further yielded a purity and deuteration rate exceeding 99%. The method of this invention is simple to operate, and the specific reaction process is as follows:

[0025]

[0026] The above-described solution will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are used to illustrate the basic principles, main features and advantages of the present invention, and the present invention is not limited to the scope of the following embodiments; the implementation conditions used in the embodiments can be further adjusted according to specific requirements, and the implementation conditions not specified are usually the conditions in conventional experiments.

[0027] In the following examples, all raw materials were either commercially available or prepared using conventional methods in the art.

[0028] Example 1:

[0029] 5L of dichloromethane and 500g of deuterated anthracene were added to a 10L reactor equipped with mechanical stirring. 474g of bromosuccinimide (NBS) was added through a feeder. The continuous feeding time was 20h, the feeding rate was 24g / h, and the reaction temperature was 20℃.

[0030] After NBS feeding is complete, stir for one hour, remove the solvent dichloromethane by vacuum distillation, add deionized water and slurry for 2 hours, release the liquid, filter, and dry under vacuum. First, purify by methanol recrystallization column chromatography, using petroleum ether as the eluent.

[0031] Yield: 91%; Deuteration rate: 99.0%; Purity: 99.1%.

[0032] Example 2

[0033] 5L of dichloromethane and 500g of deuterated anthracene were added to a 10L reactor equipped with mechanical stirring. 474g of bromosuccinimide (NBS) was added through a feeder. The continuous feeding time was 20h, the feeding rate was 24g / h, and the reaction temperature was 30℃.

[0034] After NBS feeding is complete, stir for one hour, remove the solvent dichloromethane by vacuum distillation, add deionized water and slurry for 2 hours, release the liquid, filter, and dry under vacuum. First, purify by methanol recrystallization column chromatography, using petroleum ether as the eluent.

[0035] Yield: 92%; Deuteration rate: 99.4%; Purity: 99.6%.

[0036] Example 3

[0037] 5L of dichloromethane and 500g of deuterated anthracene were added to a 10L reactor equipped with mechanical stirring. 474g of bromosuccinimide (NBS) was added through a feeder. The feeding time was 10h, the feeding rate was 48g / h, and the reaction temperature was 40℃.

[0038] After NBS feeding is complete, stir for one hour, remove the solvent dichloromethane by vacuum distillation, add deionized water and slurry for 2 hours, release the liquid, filter, and dry under vacuum. First, purify by methanol recrystallization column chromatography, using petroleum ether as the eluent.

[0039] Yield: 90%; Deuteration rate: 99.5%; Purity: 99.2%.

[0040] Example 4

[0041] 5L of dichloromethane and 500g of deuterated anthracene were added to a 10L reactor equipped with mechanical stirring. 500g of bromosuccinimide (NBS) was added through a feeder. The continuous feeding time was 30h, the feeding rate was 17g / h, and the reaction temperature was 30℃.

[0042] After NBS feeding is complete, stir for one hour, remove the solvent dichloromethane by vacuum distillation, add deionized water and slurry for 2 hours, release the liquid, filter, and dry under vacuum. First, purify by methanol recrystallization column chromatography, using petroleum ether as the eluent.

[0043] Yield: 95%; Deuteration rate: 99.5%; Purity: 99.2%.

[0044] Example 5

[0045] 5L of dichloromethane and 500g of deuterated anthracene were added to a 10L reactor equipped with mechanical stirring. 500g of bromosuccinimide (NBS) was added through a feeder. The continuous feeding time was 35h, the feeding rate was 14g / h, and the reaction temperature was 30℃.

[0046] After NBS feeding is complete, stir for one hour, remove the solvent dichloromethane by vacuum distillation, add deionized water and slurry for 2 hours, release the liquid, filter, and dry under vacuum. First, purify by methanol recrystallization column chromatography, using petroleum ether as the eluent.

[0047] Yield: 97%; Deuteration rate: 99.5%; Purity: 99.7%.

[0048] Example 6

[0049] 5L of dichloromethane and 500g of deuterated anthracene were added to a 10L reactor equipped with mechanical stirring. 500g of bromosuccinimide (NBS) was added through a feeder. The feeding time was 40h, the feeding rate was 13g / h, and the reaction temperature was 40℃.

[0050] After NBS feeding is complete, stir for one hour, remove the solvent dichloromethane by vacuum distillation, add deionized water and slurry for 2 hours, release the liquid, filter, and dry under vacuum. First, purify by methanol recrystallization column chromatography, using petroleum ether as the eluent.

[0051] Yield: 98%; Deuteration rate: 99.7%; Purity: 99.4%.

[0052] Comparative Example 1

[0053] 5L of dichloromethane and 500g of deuterated anthracene were added to a 10L reactor equipped with mechanical stirring. 474g of bromosuccinimide (NBS) was added through a feeder. The continuous feeding time was 20h, the feeding rate was 24g / h, and the reaction temperature was 10℃.

[0054] After NBS feeding is complete, stir for one hour, remove the solvent dichloromethane by vacuum distillation, add deionized water and slurry for 2 hours, release the liquid, filter, and dry under vacuum. First, purify by methanol recrystallization column chromatography, using petroleum ether as the eluent.

[0055] Yield: 30%; Deuteration rate: 99.5%; Purity: 96.4%.

[0056] Comparative Example 2

[0057] 5L of dichloromethane and 500g of deuterated anthracene were added to a 10L reactor equipped with mechanical stirring. 474g of bromosuccinimide (NBS) was added through a feeder. The feeding time was 5h, the feeding rate was 95g / h, and the reaction temperature was 40℃.

[0058] After NBS feeding is complete, stir for one hour, remove the solvent dichloromethane by vacuum distillation, add deionized water and slurry for 2 hours, release the liquid, filter, and dry under vacuum. First, purify by methanol recrystallization column chromatography, using petroleum ether as the eluent.

[0059] Yield: 63%; Deuteration rate: 99.1%; Purity: 97.5%.

[0060] Comparative Example 3

[0061] 5L of dichloromethane and 500g of deuterated anthracene were added to a 10L reactor equipped with mechanical stirring. 474g of bromosuccinimide (NBS) was added through a feeder. The feeding time was 2h, the feeding rate was 273g / h, and the reaction temperature was 50℃.

[0062] After NBS feeding is complete, stir for one hour, remove the solvent dichloromethane by vacuum distillation, add deionized water and slurry for 2 hours, release the liquid, filter, and dry under vacuum. First, purify by methanol recrystallization column chromatography, using petroleum ether as the eluent.

[0063] Yield: 55%; Deuteration rate: 98.2%; Purity: 97%.

[0064] It should be understood that although the present invention has been described by way of example according to its preferred embodiments, it should not be limited to the above embodiments. Various modifications and variations can be made to the present invention by those skilled in the art. The reaction reagents, reaction conditions, etc., involved in the method for preparing deuterated 9-bromoanthracene can be adjusted and changed according to specific needs. Therefore, those skilled in the art can make several simple substitutions without departing from the concept and principles of the present invention, and these should all be included within the scope of protection of the present invention.

Claims

1. A method for preparing 9-bromoanthracene-D9, wherein, The preparation method includes the following steps: (1) mixing dichloromethane and deuterated anthracene in a reactor; (2) adding bromosuccinimide NBS; (3) vacuum distillation; (4) separation and purification, wherein in step (2), NBS is added by a feeder in a continuous feeding manner at a feed rate of 13-48 g / h, and the reaction temperature is 16-44℃.

2. The method according to claim 1, wherein, The reactor is a stirred bed or a reaction vessel equipped with mechanical stirring.

3. The preparation method according to claim 1, wherein, In step (1), the mass-to-volume ratio of dichloromethane and deuterated anthracene is 70-120 g / L.

4. The preparation method according to claim 3, wherein, In step (1), the mass-to-volume ratio of dichloromethane and deuterated anthracene is 80-110 g / L.

5. The preparation method according to claim 4, wherein, In step (1), the mass-to-volume ratio of dichloromethane and deuterated anthracene is 90-100 g / L.

6. The preparation method according to claim 1, wherein, The vacuum distillation in step (3) includes adding deionized water to make a pulp, filtering, vacuum drying, and removing the solvent dichloromethane.

7. The preparation method according to claim 1, wherein, The separation and purification in step (4) includes recrystallization with methanol and column chromatography separation and purification.

8. The preparation method according to claim 7, wherein, The separation and purification in step (4) also includes using petroleum ether as the eluent.

9. The preparation method according to claim 1, wherein, The mass of NBS added in step (2) is 400-600 g.

10. The preparation method according to claim 9, wherein, The mass of NBS added in step (2) is 450-550g.

11. The preparation method according to claim 10, wherein, The mass of NBS added in step (2) is 500-520g.

12. The preparation method according to claim 1, wherein, The feeding time for the reaction is 1-30 h.

13. The preparation method according to claim 12, wherein, The feeding time for the reaction is 3-25 h.

14. The preparation method according to claim 13, wherein, The feeding time for the reaction is 5-20 h.

15. The preparation method according to claim 1, wherein, The feed rate for the reaction is 17-24 g / h.

16. The preparation method according to claim 1, wherein, The reaction temperature is 18-42℃.

17. The preparation method according to claim 16, wherein, The reaction temperature is 20-40℃.

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