CN112574007B - Novel cyclohexylimine ionic liquid and method for catalyzing synthesis of butyl citrate and bisphenol F - Google Patents
Novel cyclohexylimine ionic liquid and method for catalyzing synthesis of butyl citrate and bisphenol F Download PDFInfo
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- C07C37/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring
- C07C37/11—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring by reactions increasing the number of carbon atoms
- C07C37/20—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring by reactions increasing the number of carbon atoms using aldehydes or ketones
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- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
- B01J31/02—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides
- B01J31/0234—Nitrogen-, phosphorus-, arsenic- or antimony-containing compounds
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- B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
- B01J31/02—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides
- B01J31/0234—Nitrogen-, phosphorus-, arsenic- or antimony-containing compounds
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- B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
- B01J31/02—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides
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- C07D223/02—Heterocyclic compounds containing seven-membered rings having one nitrogen atom as the only ring hetero atom not condensed with other rings
- C07D223/04—Heterocyclic compounds containing seven-membered rings having one nitrogen atom as the only ring hetero atom not condensed with other rings with only hydrogen atoms, halogen atoms, hydrocarbon or substituted hydrocarbon radicals, directly attached to ring carbon atoms
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- B01J2231/00—Catalytic reactions performed with catalysts classified in B01J31/00
- B01J2231/40—Substitution reactions at carbon centres, e.g. C-C or C-X, i.e. carbon-hetero atom, cross-coupling, C-H activation or ring-opening reactions
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Abstract
The invention provides a novel cyclohexylimine ionic liquid and a method for catalyzing the synthesis of butyl citrate and bisphenol F, which can solve the technical problem that the reaction yield needs to be further improved when the traditional cyclohexylimine ionic liquid catalyzes the synthesis of butyl citrate and bisphenol F. A novel cyclohexylimine ionic liquid is characterized in that: prepared by the following method, S1, mixing and dissolving 1, 3-propane sultone and toluene, cooling the solution, adding Mn (OAc)2Hexamethylene imine, and heating to 65 deg.CoC, reacting for 12 hours; s2, filtering the reaction solution of S1 to obtain white precipitate, rinsing and drying to obtain a white intermediate; s3, dissolving the intermediate in water, stirring, dropwise adding concentrated sulfuric acid, and heating to 80 DEGoAnd C, reacting for 16 hours to obtain yellow transparent liquid, S4, removing water from the transparent liquid by rotary evaporation, rinsing, washing and drying to obtain the novel cycloheximide ionic liquid.
Description
Technical Field
The invention relates to a novel cyclohexylimine manganese-doped ionic liquid and a method for catalyzing the synthesis of butyl citrate, wherein the butyl citrate and derivatives thereof are important chemical products, particularly tributyl citrate is colorless and transparent, has a high boiling point, has good solubility and lower toxicity, is an excellent color filtering plasticizer and has great industrial value, and the catalyst is also suitable for the synthesis of bisphenol F and is more environment-friendly than the traditional inorganic strong acid.
Background
The tri-n-butyl citrate is an ester organic compound, is colorless and transparent liquid at normal temperature, has a higher boiling point, is slightly soluble in water, and is mutually soluble with various common organic solvents. The plasticizer is prepared by reacting citric acid with n-butyl alcohol, can be directly added as a plasticizer, and can be further processed into the plasticizer acetyl tributyl citrate with excellent performance. The compound is low in toxicity, can be classified as a non-toxic plasticizer according to national standards, is a novel environment-friendly plasticizer, and can replace phthalate plasticizers limited by toxicity.
The main large companies for producing fine chemicals abroad have tributyl citrate production lines, and the corresponding special derivatives are relatively complete in variety. At present, the production scale of tributyl citrate already has a rudiment. For example, in the plasticizer industry of japan, research and production of new plasticizers such as tributyl citrate are being scaled out, and have a large proportion worldwide and are increasing. The industrial production of tributyl citrate is still blank in China, and is still in a small-scale order trial production state nowadays, further products using tributyl citrate as a raw material mostly depend on import, various synthesized plasticizer raw materials depend on import and have influence on the quality and use cost of plastic products needing plasticizers, and therefore the industrial production of tributyl citrate is urgently needed. The tributyl citrate is used as a novel chemical raw material, has low investment cost-effectiveness ratio, rich profit and quite high technical content, is a key source for replacing imported products and improving the quality of corresponding subsequent products, and can form a corresponding high-technology industrial group. Therefore, the tributyl citrate product has better research value and application prospect.
Tributyl citrate is generally prepared by esterifying citric acid and n-butanol under the action of a catalyst, the traditional catalyst is strong acid, and although the traditional catalyst is low in price and high in catalytic activity, the traditional catalyst has the defects of serious equipment corrosion, complex post-treatment process, poor reaction selection, serious environmental pollution and the like, so that the research on finding a catalyst capable of replacing concentrated sulfuric acid is quite active. In the traditional process, strong acid catalysis and dehydration reaction are generally adopted to synthesize tributyl citrate, and a phosphoric acid and concentrated sulfuric acid catalysis method is adopted, but the problems of corrosivity, difficulty in separation, incomplete reaction, generation of a large amount of inorganic wastewater and the like exist; in recent years, there have been catalytic methods such as modified acidic resins, solid acids, sodium bisulfate, ionic liquids, p-toluenesulfonic acid, heteropoly acids, and the like. The ionic liquid is a salt which is in a liquid state at or near room temperature and is completely composed of anions and cations, and is also called low-temperature molten salt. Due to its unique properties, ionic liquids are widely used in various fields of chemical research. Ionic liquids have been applied to many types of reactions as solvents for the reactions. The traditional method for synthesizing tributyl citrate by using the cycloheximide ionic liquid obtained by reacting 1, 3-propane sultone, toluene, hexamethylene imine and concentrated sulfuric acid is applied, but the reaction yield needs to be further improved.
Disclosure of Invention
The invention provides a novel cyclohexylimine ionic liquid and a method for catalyzing the synthesis of butyl citrate and bisphenol F, which can solve the technical problem that the reaction yield needs to be further improved when the traditional cyclohexylimine ionic liquid catalyzes the synthesis of butyl citrate and bisphenol F.
1. A novel cyclohexylimine ionic liquid is characterized in that: the preparation method comprises the following steps of preparing,
s1, adding 5mmol of 1, 3-propane sultone and 50mL of toluene into a reaction vessel, stirring until the mixture is completely dissolved, and cooling the solution to 0oC, adding 1 mmol Mn (OAc)25mmol of hexamethylene imine is dripped in, and the temperature is raised to 65 ℃ after drippingoC, reacting for 12 hours;
s2, filtering the reaction solution of S1 to obtain white precipitates, respectively rinsing the white precipitates with ethyl acetate and diethyl ether, and drying in an oven to obtain a white intermediate;
s3, dissolving the intermediate obtained in S2 in 20 mL of water, dropwise adding 2 mL of concentrated sulfuric acid while stirring, and heating to 80 DEGoC, reacting for 16 hours to obtain yellow transparent liquid,
s4, removing water from the transparent liquid obtained in S3 by rotary evaporation, rinsing with methanol and diethyl ether respectively, washing 80 timesoAnd drying in an oven for 6 hours to obtain the novel cycloheximide ionic liquid.
2. A method for catalyzing the synthesis of butyl citrate is characterized by comprising the following steps: comprises the following steps of (a) carrying out,
s1', heating and dissolving 1 mmol of citric acid, adding 4mmol of n-butanol, and stirring to mix uniformly;
s2 ', adding 100mg-400mg of the novel cycloheximide ionic liquid into the mixed solution obtained in S1', and heating to 70-130oC, reacting for 1.5-8h to obtain the butyl citrate.
The reaction equation is as follows:
3. a method for catalyzing the synthesis of bisphenol F is characterized in that: comprises the following steps of (a) carrying out,
s1 '', 1 mmol phenol is heated to melt, 100mg-1g of the novel cyclohexylimine ionic liquid is added, 0.4 mmol formaldehyde is added, and the mixture is heated to 60-130%oReacting for 1.5-12 h under C,
s2 '', adding 50 mg sodium bicarbonate into the reaction solution obtained in S1 '', stirring for 10 minutes to 2 hours, and separating an organic phase;
s3 '', distilling the organic phase obtained in S2 '' under reduced pressure, adding the crude product into 20 mL of toluene, heating and stirring for 0.5-10 hours, cooling to room temperature, and filtering to obtain bisphenol F.
The reaction equation is as follows:
the novel cycloheximide manganese-doped ionic liquid and the catalytic synthesis of butyl citrate are disclosed. Compared with concentrated sulfuric acid and imidazole ionic liquid adopted in the traditional process, the novel cyclohexylimine ionic liquid provided by the invention has higher catalytic performance and is more environment-friendly.
Detailed Description
In the following, the applicant has made some specific experiments on the invention, and describes the synthesis of a novel cycloheximide ionic liquid, and also describes specific steps for synthesizing butyl citrate by using the catalyst. These are merely intended to be exhaustive of the invention and do not limit the scope of the invention in any way.
A novel cyclohexylimine ionic liquid is prepared by adding 5mmol of 1, 3-propane sultone into a 100 mL flask, adding 50mL of toluene, stirring to dissolve completely, and cooling the system to 0 with ice bathoC, adding 1 mmol Mn (OAc)2Slowly adding 5mmol of cycloheximide, and heating to 65 deg.C after drippingoReacting at C for 12 hr, filtering to obtain white precipitate, rinsing the filter cake with ethyl acetate (10 mLX 3) and diethyl ether (10 mLX 3) for 3 times, respectively, and adding water at 90 deg.CoDrying in a drying oven for 12 hours to obtain a white intermediate; dissolving the intermediate in 20 mL of water, dropwise adding 2 mL of concentrated sulfuric acid while stirring, and slowly heating to 80%oReacting for 16 h to obtain yellow transparent liquid, removing water by rotary evaporation, rinsing with methanol (10 mLX 3) and diethyl ether (10 mLX 3) for 3 times, respectively, and washing after 80 timesoOven dry for 6 hours to give 938 mg of product.
Synthesis of butyl citrate test example 1
Adding 1 mmol of citric acid into a 20 mL flask, heating to dissolve, adding 4mol of n-butanol, stirring, mixing, adding 400mg of the above synthesized novel cycloheximide ionic liquid, heating to 127%oC, reacting for 1.8 h, wherein the yield is 98.5 percent, and the product selectivity is 99.6 percent.
Butyl citrate Synthesis test example 2
Adding 1 mmol citric acid into a 20 mL flask, heating to dissolve, adding 4mol n-butanol, stirring, mixing, adding 400mg of the above synthesized novel cycloheximide ionic liquid, heating to 70%oC, reacting for 8h, wherein the yield is 91% and the product selectivity is 93.8%.
Synthesis of butyl citrate test example 3
Adding 1 mmol citric acid into a 20 mL flask, heating to dissolve, adding 4mol n-butanol, stirring, mixing, adding 400mg of the above synthesized novel cycloheximide ionic liquid, heating to 100%oC, reacting for 3 hours, wherein the yield is 98.6 percent, and the product selectivity is 99.2 percent.
Synthesis of butyl citrate comparative example 1
Adding 1 mmol of citric acid into a 20 mL flask, heating to dissolve, adding 4mol of n-butanol, stirring to mix well, adding 400mg of traditional cycloheximide ionic liquid, and heating to 127%oC, reacting for 2 hours, wherein the yield is 88.9 percent, and the product selectivity is 98.5 percent.
Synthesis of butyl citrate comparative example 2
Adding 1 mmol citric acid into a 20 mL flask, heating to dissolve, adding 5mol n-butanol, stirring, mixing, adding 400mg traditional cycloheximide ionic liquid, heating to 127%oC, reacting for 2 hours, wherein the yield is 97.2 percent, and the product selectivity is 99.3 percent.
Synthesis of butyl citrate comparative example 3
Adding 1 mmol citric acid into a 20 mL flask, heating to dissolve, adding 5mol n-butanol, stirring, mixing, adding 400mg traditional cycloheximide ionic liquid, heating to 127%oC, reacting for 3 hours, wherein the yield is 97.3 percent, and the product selectivity is 99.3 percent.
The difference between the conventional methods for preparing cycloheximide-based ionic liquids of comparative examples 1 to 3 and the novel methods for preparing cycloheximide-based ionic liquids is that no Mn (OAc) is present2And (4) adding.
Bisphenol F Synthesis test example 1
Adding 1 mmol phenol into a 20 mL flask, heating to completely melt, adding 400mg of novel cycloheximide ionic liquid, adding 0.4 mmol formaldehyde at 42%oReacting for 6 hours under the condition of C, adding 50 mg of sodium bicarbonate, stirring for 30 minutes, separating an organic phase, distilling under reduced pressure, dissolving a crude product in 20 mL of toluene, heating and stirring for 1 hour, cooling to room temperature, and filtering to obtain a pure product 59 mg, wherein the yield is 74 percent, and the selectivity of the product is 91 percent.
Bisphenol F Synthesis test example 2
Adding 1 mmol phenol into a 20 mL flask, heating to completely melt, adding 400mg of the novel cycloheximide ionic liquid synthesized in claim 1, adding 0.4 mmol formaldehyde at 55%oC is belowReacting for 7 hours, adding 50 mg of sodium bicarbonate, stirring for 50 minutes, separating an organic phase, distilling under reduced pressure, dissolving a crude product in 20 mL of toluene, heating and stirring for 2 hours, cooling to room temperature, and filtering to obtain a pure product, wherein the yield is 71%, and the selectivity of the product is 92%.
Bisphenol F Synthesis test example 3
Adding 1 mmol phenol into a 20 mL flask, heating to completely melt, adding 200mg of the novel cycloheximide ionic liquid synthesized in claim 1, adding 0.4 mmol formaldehyde, and dissolving at 50 deg.CoReacting for 8 hours at C, adding 50 mg of sodium bicarbonate, stirring for 2 hours, separating an organic phase, distilling under reduced pressure, dissolving a crude product in 20 mL of toluene, heating and stirring for 4 hours, cooling to room temperature, and filtering to obtain a pure product, wherein the yield is 73%, and the selectivity of the product is 95%.
Bisphenol F Synthesis test example 4
Adding 1 mmol phenol into a 20 mL flask, heating to completely melt, adding 400mg of the novel cycloheximide ionic liquid synthesized in claim 1, adding 0.4 mmol formaldehyde, and dissolving at 50 deg.CoAnd C, reacting for 3 hours, adding 50 mg of sodium bicarbonate, stirring for 1 hour, separating an organic phase, distilling under reduced pressure, dissolving the crude product in 20 mL of toluene, heating and stirring for 1 hour, cooling to room temperature, and filtering to obtain a pure product, wherein the yield is 70%, and the product selectivity is 91%.
Claims (1)
1. A method for catalyzing the synthesis of butyl citrate is characterized by comprising the following steps: comprises the following steps of (a) carrying out,
s1', heating and dissolving 1 mmol of citric acid, adding 4mmol of n-butanol, and stirring to mix uniformly;
s2 ', adding 400mg of cycloheximide ionic liquid into the mixed solution obtained in S1', and heating to 127 DEGoC, reacting for 1.8 h to obtain butyl citrate;
the reaction equation is as follows:
the cycloheximide ionic liquid is prepared by the following method,
s1, adding 5mmol of 1, 3-propane sultone and 50mL of toluene into a reaction vessel, stirring until the mixture is completely dissolved, and cooling the solution to 0oC, adding 1 mmol Mn (OAc)2Dropwise adding 5mmol of cycloheximide, and heating to 65 DEG after dropwise addingoC, reacting for 12 hours;
s2, filtering the reaction solution of S1 to obtain a white precipitate, rinsing the white precipitate with ethyl acetate and diethyl ether respectively, and dissolving the white precipitate in 90 DEG CoDrying in a drying oven for 12 hours to obtain a white intermediate;
s3, dissolving the intermediate obtained in S2 in 20 mL of water, dropwise adding 2 mL of concentrated sulfuric acid while stirring, and heating to 80%oC, reacting for 16 hours to obtain yellow transparent liquid;
s4, removing water from the transparent liquid obtained in S3 by rotary evaporation, rinsing with methanol and diethyl ether respectively, washing with water, and 80% washingoAnd drying in an oven for 6 hours to obtain the cycloheximide ionic liquid.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101348435A (en) * | 2008-09-04 | 2009-01-21 | 华东师范大学 | Method for preparing tributyl citrate with ion liquid as catalyst |
| CN102285883B (en) * | 2011-06-17 | 2013-07-24 | 宜昌五帝机电有限公司 | Method for synthesizing tributyl citrate (TBC) by adopting composite ionic liquid catalyst |
| CN102584541B (en) * | 2012-01-18 | 2015-11-25 | 湘潭大学 | A kind of 1-alkyl-3-methylimidazole acidic ionic liquid prepares the method for Bisphenol F |
| CN104785294B (en) * | 2015-03-16 | 2017-10-13 | 浙江工商大学 | A kind of ionic liquid-based catalyst and its preparation method and application |
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