CN114409517A - 2-bromofluorenone and preparation method thereof - Google Patents
2-bromofluorenone and preparation method thereof Download PDFInfo
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- CN114409517A CN114409517A CN202111651246.1A CN202111651246A CN114409517A CN 114409517 A CN114409517 A CN 114409517A CN 202111651246 A CN202111651246 A CN 202111651246A CN 114409517 A CN114409517 A CN 114409517A
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- bromofluorenone
- dibromohydantoin
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
- C07C45/61—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups
- C07C45/63—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups by introduction of halogen; by substitution of halogen atoms by other halogen atoms
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
- C07C45/78—Separation; Purification; Stabilisation; Use of additives
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C2603/00—Systems containing at least three condensed rings
- C07C2603/02—Ortho- or ortho- and peri-condensed systems
- C07C2603/04—Ortho- or ortho- and peri-condensed systems containing three rings
- C07C2603/06—Ortho- or ortho- and peri-condensed systems containing three rings containing at least one ring with less than six ring members
- C07C2603/10—Ortho- or ortho- and peri-condensed systems containing three rings containing at least one ring with less than six ring members containing five-membered rings
- C07C2603/12—Ortho- or ortho- and peri-condensed systems containing three rings containing at least one ring with less than six ring members containing five-membered rings only one five-membered ring
- C07C2603/18—Fluorenes; Hydrogenated fluorenes
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Abstract
The embodiment of the invention provides 2-bromofluorenone and a preparation method thereof, wherein dibromohydantoin is used for replacing liquid bromine, the active bromine content of the dibromohydantoin in the embodiment is high, the severe pollution of the liquid bromine as a brominating reagent to the environment is avoided, and the safety of production operation is improved; the tetrabutylammonium bromide catalyst and the dibromohydantoin are added in batches and are controlled to react in a low-temperature range, so that the generation of a byproduct 2, 7-dibromofluorenone is avoided; firstly, carrying out primary bromine removal by adopting a saturated sodium bisulfite solution, and then carrying out secondary bromine removal by using a bromine removal agent added in bromine removal washing for purification so as to ensure that the purity of the obtained 2-bromofluorenone product can reach 99%; and the solid raw material after the crystallization mother liquor is recovered can be recycled for reaction.
Description
Technical Field
The invention relates to the technical field of fine chemical engineering, and particularly relates to a preparation method of 2-bromofluorenone.
Background
The description of the background of the invention pertaining to the related art to which this invention pertains is given for the purpose of illustration and understanding only of the summary of the invention and is not to be construed as an admission that the applicant is explicitly or implicitly admitted to be prior art to the date of filing this application as first filed with this invention.
In recent years, fluorenone and derivatives thereof become important functional compounds, 2-bromofluorenone is an important one of the compounds, is used for preparing functional polymer materials, medicines, pesticides and photosensitive dyes, and particularly has wide application prospects in the field of organic electroluminescent materials.
At present, the preparation methods of 2-bromofluorenone reported at home and abroad mainly comprise two types, namely a bromination method and an oxidation method. The bromination method is to synthesize 2-bromofluorenone by using 9-fluorenone and a bromination reagent as raw materials, some of the raw materials adopt liquid bromine as the bromination reagent, and the bromination reagent has the characteristics of volatility and high toxicity, so that the method is not beneficial to safe production, and the subsequent purification process cannot efficiently remove the byproduct 2, 7-dibromofluorenone, so that a high-purity 2-bromofluorenone product cannot be obtained. The oxidation method is to prepare 2-bromofluorenone by oxidizing 2-bromofluorene in a liquid phase, and some of the oxidation methods adopt organic solvents pyridine, tetrahydrofuran and N, N-dimethylformamide as reaction media, and the organic solvents cause serious environmental pollution; some of the method adopts a water phase as a reaction medium, so that the moisture content of a target product is increased in the oxidation process, and the target product is difficult to remove completely in later purification, so that a high-quality 2-bromofluorenone product cannot be obtained.
Disclosure of Invention
The invention provides a preparation method of 2-bromofluorenone based on at least one of the technical problems, and the method is economical, safe, environment-friendly, efficient and suitable for industrial production.
The embodiment of the invention provides a preparation method of 2-bromofluorenone, which comprises the following steps:
(1) mixing 9-fluorenone, tetrabutylammonium bromide and water, heating to 40-60 ℃, adding dibromohydantoin in batches, and reacting at a stirring speed of 50-100 r/min; wherein the weight ratio of the 9-fluorenone to the dibromohydantoin is 1 (1.5-2); the weight ratio of the 9-fluorenone to the tetrabutylammonium bromide to the water is 1: 0.01-0.1: 3-8;
(2) after the reaction is finished, cooling to room temperature, adding a saturated sodium bisulfite solution, centrifuging, removing bromine, and washing to obtain a 2-bromofluorenone crude product; wherein the weight ratio of the sodium bisulfite solution to the water is 1: 2-5;
(3) mixing the 2-bromofluorenone crude product with a crystallization solvent, heating to 65-75 ℃, fully dissolving, cooling to room temperature, centrifuging, spraying to remove impurities, and thus obtaining the 2-bromofluorenone.
In some embodiments, the dibromohydantoin is added at each time interval of 0.5 to 1.5h in step (1); the reaction time is 10-16 h.
In some embodiments, the amount of dibromohydantoin added in step (1) is from 30 to 50kg/h, with the weight of dibromohydantoin added decreasing in sequence with increasing number of times.
In some embodiments, the bromine removal agent added in the bromine removal wash in step (2) is sodium hydroxide; the weight ratio of sodium hydroxide to water in the bromine removal washing is 1: 5-10.
In some embodiments, the crystallization solvent in step (3) is absolute ethanol; the weight ratio of the 2-bromofluorenone crude product to the absolute ethyl alcohol is 1: 4-7.
In some embodiments, the centrifuged absolute ethanol in the step (3) is recovered by distillation, and the solvent used in the spray impurity removal is distilled and recovered absolute ethanol; the weight ratio of the crude 2-bromofluorenone to the recovered solvent anhydrous ethanol in the spraying impurity removal is 1: 0.2-1.
According to a second aspect of the embodiments of the present invention, there is provided a high-purity 2-bromofluorenone prepared by the method described in any of the above embodiments, wherein the purity of the 2-bromofluorenone is 99.90-99.95%.
The embodiment of the invention provides 2-bromofluorenone and a preparation method thereof, wherein dibromohydantoin is used for replacing liquid bromine, the active bromine content of the dibromohydantoin in the embodiment is high, the severe pollution of the liquid bromine as a brominating reagent to the environment is avoided, and the safety of production operation is improved; the tetrabutylammonium bromide catalyst and the dibromohydantoin are added in batches and are controlled to react in a low-temperature range, so that the generation of a byproduct 2, 7-dibromofluorenone is avoided; firstly, carrying out primary bromine removal by adopting a saturated sodium bisulfite solution, and then carrying out secondary bromine removal by using a bromine removal agent added in bromine removal washing for purification so as to ensure that the purity of the obtained 2-bromofluorenone product can reach 99%; and the solid raw material after the crystallization mother liquor is recovered can be recycled for reaction.
Detailed Description
In order that the above objects, features and advantages of the present invention can be more clearly understood, the present invention will be described in further detail with reference to specific embodiments. It should be noted that the embodiments of the present invention and features of the embodiments may be combined with each other without conflict.
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced in other ways than those specifically described herein, and therefore the scope of the present invention is not limited by the specific embodiments disclosed below.
Example 1
The environment-friendly type 2-bromofluorenone industrialized preparation method comprises the following steps:
1) 1400L of water, 15kg of tetrabutylammonium bromide as a catalyst and 180kg of 9-fluorenone are added into a 3000L enamel kettle provided with an emptying recovery device and a mechanical stirrer and stirred and mixed uniformly at the speed of 100 r/min. Heating to 45 ℃ at a stirring speed of 100r/min, then adding 300kg of dibromohydantoin in batches, and adding 50kg/h of the first batch, 48kg/h of the second batch, 45kg/h of the third batch, 43kg/h of the fourth batch, 40kg/h of the fifth batch, 38kg/h of the sixth batch and 36kg/h of the seventh batch at intervals of 1h while stirring; after the dibromohydantoin is completely added, the reaction is continued for 10 hours at the temperature of 55 ℃.
2) After the reaction is finished, the temperature is reduced to room temperature, 300L of saturated sodium bisulfite solution is added for washing, and the crude product of the 2-bromofluorenone is obtained after centrifugation and washing by 250L of NAOH solution with the concentration of 8wt percent. The purity of the crude product is 99.3 percent by liquid chromatography assay. The reaction mother liquor is collected and added with the catalyst, and then can be recycled.
3) Uniformly mixing the 2-bromofluorenone crude product and an absolute ethyl alcohol solvent in a weight ratio of 1:6 in a crystallization kettle, stirring and heating to 70 ℃, fully dissolving, cooling to room temperature, centrifuging, adding absolute ethyl alcohol with the weight 5 times of that of the 2-bromofluorenone crude product, and spraying to remove impurities to obtain a 2-bromofluorenone product. And distilling and recovering the centrifuged absolute ethyl alcohol solvent, and recrystallizing for recycling. The 2-bromofluorenone product obtained by drying after recrystallization accounts for 238.3kg, the purity is 99 percent, and the yield is 85 percent. The solid raw material after the mother liquor of crystallization is recovered is reused for reaction, and 60kg of 2-bromofluorenone product is obtained after crystallization and drying.
The enamel kettle is provided with an emptying recovery device which can absorb acidic gases such as hydrogen bromide and the like generated in the reaction process, thereby avoiding the pollution to the environment.
Example 2
The environment-friendly type 2-bromofluorenone industrialized preparation method comprises the following steps:
2) 1) in a 2000L enamel kettle with an emptying recovery device and mechanical stirring, 1000L water and 2kg catalyst tetrabutylammonium bromide and 120kg 9-fluorenone are added and stirred and mixed evenly. Heating to 45 ℃ under the condition of stirring, then adding 180kg of dibromohydantoin in batches, and adding one batch at intervals of 1.2h while stirring according to the first batch of 45kg/h, the second batch of 40kg/h, the third batch of 34kg/h, the fourth batch of 31kg/h and the fifth batch of 30 kg/h; after the dibromohydantoin is completely added, the reaction is continued for 12 hours at the temperature of 45 ℃.
2) After the reaction is finished, the temperature is reduced to room temperature, 200L of saturated sodium bisulfite solution is added for washing, and then the solution is centrifuged, and 200L of NAOH solution with the concentration of 8wt% is washed to obtain the crude product of the 2-bromofluorenone. The purity of the crude product is 99.5% by liquid chromatography assay. Collecting the reaction mother liquor for recycling.
3) Uniformly mixing the 2-bromofluorenone crude product and an absolute ethyl alcohol solvent in a weight ratio of 1:6 in a crystallization kettle, stirring and heating to 70 ℃, fully dissolving, cooling to room temperature, centrifuging, and adding absolute ethyl alcohol which is 7 times of the weight of the 2-bromofluorenone crude product. And distilling and recovering the centrifuged absolute ethyl alcohol solvent, and recrystallizing for recycling. The 2-bromofluorenone product obtained by drying after recrystallization accounts for 158.2kg, the purity is 99.9 percent, and the yield is 86.3 percent. The solid raw material after the mother solution of crystallization is recovered is reused for reaction, and 50.8kg of 2-bromofluorenone product is obtained after crystallization and drying.
The enamel kettle is provided with an emptying recovery device which can absorb acidic gases such as hydrogen bromide and the like generated in the reaction process, thereby avoiding the pollution to the environment.
Example 3
The environment-friendly type 2-bromofluorenone industrialized preparation method comprises the following steps:
3) 1) in a 1000L enamel kettle with an emptying recovery device and mechanical stirring, 500L water, 1kg catalyst tetrabutyl ammonium bromide and 65kg 9-fluorenone are added and stirred and mixed evenly. Heating to 45 ℃ under the condition of stirring, then adding 100kg of dibromohydantoin in batches, and adding one batch at intervals of 1.5h according to 35kg/h of the first batch, 33kg/h of the second batch and 32kg/h of the third batch while stirring; after the dibromohydantoin is completely added, the reaction is continued for 16 hours at the temperature of 45 ℃.
2) After the reaction is finished, the temperature is reduced to room temperature, 100L of saturated sodium bisulfite solution is added for washing, and then the crude product of the 2-bromofluorenone is obtained after centrifugation and 50L of NAOH solution with the concentration of 8wt percent. The purity of the crude product is 99.1% by liquid chromatography assay. Collecting the reaction mother liquor for recycling.
3) Uniformly mixing the 2-bromofluorenone crude product and an absolute ethyl alcohol solvent in a weight ratio of 1:6 in a crystallization kettle, stirring and heating to 70 ℃, fully dissolving, cooling to room temperature, centrifuging, and adding absolute ethyl alcohol with the weight 6 times of that of the 2-bromofluorenone crude product. And distilling and recovering the centrifuged absolute ethyl alcohol solvent, and recrystallizing for recycling. The 2-bromofluorenone product obtained by drying after recrystallization accounts for 75.6kg, the purity is 99.1 percent, and the yield is 86.7 percent. And (3) recycling the solid raw material after the crystallization mother liquor is recovered, repeatedly utilizing the solid raw material for reaction, crystallizing and drying to obtain 22.2kg of 2-bromofluorenone product.
The enamel kettle is provided with an emptying recovery device which can absorb acidic gases such as hydrogen bromide and the like generated in the reaction process, thereby avoiding the pollution to the environment.
By adopting the preparation method, the yield is over 99 percent, and the product purity is over 99.90 percent.
Comparative example 1
According to the technical scheme in the comparative example, 300kg of dibromohydantoin is divided into 6 batches without stirring, each batch is added at a rate of 50kg/h, and after the dibromohydantoin is completely added, the reaction is continued for 10h at a temperature of 55 ℃. Other technical features are the same as those of embodiment 1. The 2-bromofluorenone product obtained by drying after recrystallization accounts for 196.4kg, the purity is 96 percent, and the yield is 80 percent. And (3) recycling the solid raw material after the crystallization mother liquor is recovered, repeatedly utilizing the solid raw material for reaction, crystallizing and drying to obtain 45kg of 2-bromofluorenone product.
Comparative example 2
In this comparative example, 300L of saturated sodium bisulfite solution was not added. Other technical features are the same as those of embodiment 1. The 2-bromofluorenone product obtained by drying after recrystallization accounts for 210.6kg, the purity is 98 percent, and the yield is 81 percent. The solid raw material after the mother liquor of crystallization is recovered is reused for reaction, and 48kg of 2-bromofluorenone product is obtained after crystallization and drying.
Comparative example 3
According to the technical scheme in the comparative example, 300kg of dibromohydantoin is added into a batch according to the first batch of 36kg/h, the second batch of 38kg/h, the third batch of 40kg/h, the fourth batch of 43kg/h, the fifth batch of 45kg/h, the sixth batch of 48kg/h and the seventh batch of 50kg/h, and the batch is stirred at intervals of 1 h. Other technical features are the same as those of embodiment 1. The 2-bromofluorenone product obtained by drying after recrystallization accounts for 220.6kg, the purity is 98.6 percent, and the yield is 82 percent. The solid raw material after the mother liquor of crystallization is recovered is reused for reaction, and 52kg of 2-bromofluorenone product is obtained after crystallization and drying.
Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.
The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (7)
1. The preparation method of 2-bromofluorenone is characterized by comprising the following steps:
(1) mixing 9-fluorenone, tetrabutylammonium bromide and water, heating to 40-60 ℃, adding dibromohydantoin in batches, and reacting at a stirring speed of 50-100 r/min; wherein the weight ratio of the 9-fluorenone to the dibromohydantoin is 1 (1.5-2); the weight ratio of the 9-fluorenone to the tetrabutylammonium bromide to the water is 1: 0.01-0.1: 3-8;
(2) after the reaction is finished, cooling to room temperature, adding a saturated sodium bisulfite solution, centrifuging, removing bromine, and washing to obtain a 2-bromofluorenone crude product; wherein the weight ratio of the sodium bisulfite solution to the water is 1: 2-5;
(3) mixing the 2-bromofluorenone crude product with a crystallization solvent, heating to 65-75 ℃, fully dissolving, cooling to room temperature, centrifuging, spraying to remove impurities, and thus obtaining the 2-bromofluorenone.
2. The production method according to claim 1,
in the step (1), the time interval of adding the dibromohydantoin every time is 0.5-1.5 h; the reaction time is 10-16 h.
3. The production method according to claim 2,
the adding amount of the dibromohydantoin in the step (1) is 30-50kg/h, and the weight of the dibromohydantoin added in each time is reduced along with the increasing times of the dibromohydantoin.
4. The production method according to claim 1,
the bromine removing agent added in the bromine removing washing in the step (2) is sodium hydroxide; the weight ratio of sodium hydroxide to water in the bromine removal washing is 1: 5-10.
5. The production method according to claim 1,
the crystallization solvent in the step (3) is absolute ethyl alcohol; the weight ratio of the 2-bromofluorenone crude product to the absolute ethyl alcohol is 1: 4-7.
6. The production method according to claim 5,
distilling and recovering the centrifuged absolute ethyl alcohol in the step (3), wherein the solvent used in the spraying impurity removal is distilled and recovered absolute ethyl alcohol; the weight ratio of the crude 2-bromofluorenone to the recovered solvent anhydrous ethanol in the spraying impurity removal is 1: 0.2-1.
7. The high-purity 2-bromofluorenone is characterized by being prepared by the method of any one of claims 1 to 6, wherein the purity of the 2-bromofluorenone is 99.90-99.95%.
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|---|---|---|---|---|
| CN101318888A (en) * | 2008-07-09 | 2008-12-10 | 江南大学 | Process for synthesizing 2,7-dibromo fluorenone |
| CN102718625A (en) * | 2011-03-29 | 2012-10-10 | 上海引盛生物科技有限公司 | Preparation method for 9, 9,-dimethyl-2-bromofluorene |
| CN103102245A (en) * | 2011-11-09 | 2013-05-15 | 上海引盛生物科技有限公司 | Preparation method for 1-dibromopyrene |
| CN104774141A (en) * | 2015-05-13 | 2015-07-15 | 河南省商业科学研究所有限责任公司 | Synthetic method of 2-Bromo-9-fluorenone |
| CN107253905A (en) * | 2017-05-11 | 2017-10-17 | 张照明 | A kind of method that the Fluorenone of high-purity 9 is prepared with Industrial fluorene |
| CN110357768A (en) * | 2019-08-28 | 2019-10-22 | 郑州圣壹新材料科技有限公司 | A kind of preparation method of 2- bromine Fluorenone |
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2021
- 2021-12-31 CN CN202111651246.1A patent/CN114409517A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101318888A (en) * | 2008-07-09 | 2008-12-10 | 江南大学 | Process for synthesizing 2,7-dibromo fluorenone |
| CN102718625A (en) * | 2011-03-29 | 2012-10-10 | 上海引盛生物科技有限公司 | Preparation method for 9, 9,-dimethyl-2-bromofluorene |
| CN103102245A (en) * | 2011-11-09 | 2013-05-15 | 上海引盛生物科技有限公司 | Preparation method for 1-dibromopyrene |
| CN104774141A (en) * | 2015-05-13 | 2015-07-15 | 河南省商业科学研究所有限责任公司 | Synthetic method of 2-Bromo-9-fluorenone |
| CN107253905A (en) * | 2017-05-11 | 2017-10-17 | 张照明 | A kind of method that the Fluorenone of high-purity 9 is prepared with Industrial fluorene |
| CN110357768A (en) * | 2019-08-28 | 2019-10-22 | 郑州圣壹新材料科技有限公司 | A kind of preparation method of 2- bromine Fluorenone |
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