CN113121325A - Preparation method of 2,5-dihydroxy benzaldehyde - Google Patents
Preparation method of 2,5-dihydroxy benzaldehyde Download PDFInfo
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- CN113121325A CN113121325A CN202110310683.0A CN202110310683A CN113121325A CN 113121325 A CN113121325 A CN 113121325A CN 202110310683 A CN202110310683 A CN 202110310683A CN 113121325 A CN113121325 A CN 113121325A
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- solvent
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- methoxyphenol
- hydroxy
- methoxybenzaldehyde
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- CLFRCXCBWIQVRN-UHFFFAOYSA-N 2,5-dihydroxybenzaldehyde Chemical compound OC1=CC=C(O)C(C=O)=C1 CLFRCXCBWIQVRN-UHFFFAOYSA-N 0.000 title claims abstract description 47
- 238000002360 preparation method Methods 0.000 title claims abstract description 10
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 claims abstract description 42
- FZHSPPYCNDYIKD-UHFFFAOYSA-N 5-methoxysalicylaldehyde Chemical compound COC1=CC=C(O)C(C=O)=C1 FZHSPPYCNDYIKD-UHFFFAOYSA-N 0.000 claims abstract description 28
- ZMANZCXQSJIPKH-UHFFFAOYSA-N Triethylamine Chemical compound CCN(CC)CC ZMANZCXQSJIPKH-UHFFFAOYSA-N 0.000 claims abstract description 21
- 239000002904 solvent Substances 0.000 claims abstract description 21
- NWVVVBRKAWDGAB-UHFFFAOYSA-N p-methoxyphenol Chemical compound COC1=CC=C(O)C=C1 NWVVVBRKAWDGAB-UHFFFAOYSA-N 0.000 claims abstract description 17
- TWRXJAOTZQYOKJ-UHFFFAOYSA-L Magnesium chloride Chemical compound [Mg+2].[Cl-].[Cl-] TWRXJAOTZQYOKJ-UHFFFAOYSA-L 0.000 claims abstract description 16
- 238000006243 chemical reaction Methods 0.000 claims abstract description 12
- 238000006170 formylation reaction Methods 0.000 claims abstract description 10
- VSCWAEJMTAWNJL-UHFFFAOYSA-K aluminium trichloride Chemical compound Cl[Al](Cl)Cl VSCWAEJMTAWNJL-UHFFFAOYSA-K 0.000 claims abstract description 9
- 239000012295 chemical reaction liquid Substances 0.000 claims abstract description 9
- 238000001035 drying Methods 0.000 claims abstract description 9
- 229930040373 Paraformaldehyde Natural products 0.000 claims abstract description 8
- 238000010520 demethylation reaction Methods 0.000 claims abstract description 8
- 229910001629 magnesium chloride Inorganic materials 0.000 claims abstract description 8
- 238000000034 method Methods 0.000 claims abstract description 8
- 239000003960 organic solvent Substances 0.000 claims abstract description 8
- 229920002866 paraformaldehyde Polymers 0.000 claims abstract description 8
- 239000007788 liquid Substances 0.000 claims abstract description 7
- 239000002994 raw material Substances 0.000 claims abstract description 7
- -1 alkyl nitrile Chemical class 0.000 claims abstract description 6
- 230000022244 formylation Effects 0.000 claims abstract description 6
- 238000005406 washing Methods 0.000 claims abstract description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 5
- 239000003054 catalyst Substances 0.000 claims abstract description 4
- 239000003153 chemical reaction reagent Substances 0.000 claims abstract description 4
- 238000001704 evaporation Methods 0.000 claims abstract description 4
- YMWUJEATGCHHMB-UHFFFAOYSA-N Dichloromethane Chemical compound ClCCl YMWUJEATGCHHMB-UHFFFAOYSA-N 0.000 claims description 18
- WEVYAHXRMPXWCK-UHFFFAOYSA-N Acetonitrile Chemical compound CC#N WEVYAHXRMPXWCK-UHFFFAOYSA-N 0.000 claims description 12
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims description 6
- RTZKZFJDLAIYFH-UHFFFAOYSA-N ether Substances CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 claims description 6
- SCYULBFZEHDVBN-UHFFFAOYSA-N 1,1-Dichloroethane Chemical compound CC(Cl)Cl SCYULBFZEHDVBN-UHFFFAOYSA-N 0.000 claims description 4
- 238000002425 crystallisation Methods 0.000 claims description 2
- 230000008025 crystallization Effects 0.000 claims description 2
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 claims description 2
- 239000003208 petroleum Substances 0.000 claims description 2
- 239000004973 liquid crystal related substance Substances 0.000 abstract description 5
- 238000009776 industrial production Methods 0.000 abstract description 4
- 150000001875 compounds Chemical class 0.000 abstract description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 8
- 238000010992 reflux Methods 0.000 description 6
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 4
- 230000015572 biosynthetic process Effects 0.000 description 4
- 238000003786 synthesis reaction Methods 0.000 description 4
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 239000012043 crude product Substances 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 239000000975 dye Substances 0.000 description 1
- LHWWETDBWVTKJO-UHFFFAOYSA-N et3n triethylamine Chemical compound CCN(CC)CC.CCN(CC)CC LHWWETDBWVTKJO-UHFFFAOYSA-N 0.000 description 1
- 125000001033 ether group Chemical group 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 238000011031 large-scale manufacturing process Methods 0.000 description 1
- 238000002386 leaching Methods 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Classifications
-
- 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
- C07C45/64—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 functional groups containing oxygen only in singly bound form
-
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
Abstract
The invention discloses a preparation method of 2,5-dihydroxybenzaldehyde, which is used for preparing an important intermediate of a liquid crystal compound and relates to the technical field of liquid crystal; the method comprises the steps of taking p-methoxyphenol as a raw material, taking alkyl nitrile as a solvent, paraformaldehyde as a formylation reagent, magnesium chloride and triethylamine as catalysts, reacting for 2-4 hours, extracting a reaction liquid by using an organic solvent, washing with water, drying, evaporating to remove the solvent to obtain liquid 2-hydroxy-5-methoxybenzaldehyde, taking methylbenzene as a solvent, and carrying out demethylation reaction on the obtained 2-hydroxy-5-methoxybenzaldehyde under the action of anhydrous aluminum trichloride to obtain 2, 5-dihydroxybenzaldehyde; reacting for 2-4 hours, washing the reaction solution, extracting with an organic solvent, drying, evaporating to remove the solvent, and crystallizing the solvent; the route of the invention has cheap and easily obtained raw materials, simple operation and convenient industrial production.
Description
Technical Field
The invention discloses a preparation method of 2,5-dihydroxybenzaldehyde, which is used for preparing an important intermediate of a liquid crystal compound and relates to the technical field of liquid crystal.
Background
2,5-dihydroxy benzaldehyde, English name 2, 5-dihydrodihydroxybenzaldehyde, CAS number 1194-98-5, molecular formula C7H6O3And (3) property: yellow crystal powder is used as chemical intermediate for medicine, liquid crystal and dye.
The method for preparing 2,5-dihydroxybenzaldehyde with the patent name of CN110330417A adopts a three-step method provided in the patent application, and has the advantages of long route, high operation risk and large industrial production risk; therefore, a preparation method of 2,5-dihydroxy benzaldehyde with short route, simple operation and small industrial production risk is lacked at present.
Disclosure of Invention
The invention aims to: provides a preparation method of 2,5-dihydroxy benzaldehyde, which has short route and simple and convenient operation and is suitable for industrial large-scale production.
The technical scheme adopted by the invention is as follows: a preparation method of 2,5-dihydroxy benzaldehyde uses p-methoxyphenol as raw material, and obtains 2,5-dihydroxy benzaldehyde through formylation reaction and demethylation reaction in sequence, the reaction equation is,
wherein p-methoxyphenol is treated with paraformaldehyde (CH)2O) n, Triethylamine Et3N, magnesium chloride Mgcl2Formylation reaction, and reaction with AlCl3Demethylating to obtain 2,5-dihydroxy benzaldehyde; the method has the advantages of short reaction route, mild reaction conditions and convenience for industrial production.
The specific preparation steps of the 2,5-dihydroxy benzaldehyde are as follows:
s1, formylation, namely reacting p-methoxyphenol serving as a raw material, alkyl nitrile serving as a solvent, paraformaldehyde serving as a formylation reagent, magnesium chloride and triethylamine serving as catalysts for 2-4 hours, extracting a reaction liquid by using an organic solvent, washing by using water, drying, and evaporating to remove the solvent to obtain liquid 2-hydroxy-5-methoxybenzaldehyde, wherein the mass ratio of the alkyl nitrile to the p-methoxyphenol is 3-10: 1; the molar ratio of paraformaldehyde to p-methoxyphenol is 1-3: 1; the molar ratio of the magnesium chloride to the p-methoxyphenol is 1-3: 1; the molar ratio of triethylamine to p-methoxyphenol is 1-3: 1;
s2, demethylation reaction: taking methylbenzene as a solvent, and carrying out demethylation reaction on the 2-hydroxy-5-methoxybenzaldehyde obtained in the step S1 under the action of anhydrous aluminum trichloride to obtain 2, 5-dihydroxybenzaldehyde; the mass ratio of the toluene to the 2-hydroxy-5-methoxybenzaldehyde is 10-20: 1; the molar ratio of aluminum trichloride to 2-hydroxy-5-methoxybenzaldehyde is 1-3: 1, the reaction is carried out for 2-4 hours, the reaction liquid is washed by water, extracted by an organic solvent, dried, evaporated to remove the solvent, and crystallized by the solvent.
The alkylnitrile of step S1 is acetonitrile.
The organic solvent in the steps S1 and S2 is one or a combination of several of toluene, methyl tertiary ether, dichloromethane and dichloroethane.
The solvent in the solvent crystallization in the step S2 comprises one or a combination of several of dichloromethane, dichloroethane, petroleum ether and methanol.
In summary, due to the adoption of the technical scheme, the invention has the beneficial effects that:
the method takes p-methoxyphenol as a raw material, performs formylation reaction by matching with a solvent, a formylation reagent and a catalyst in a proper proportion, and then performs demethylation reaction by using aluminum trichloride and the solvent in a proper proportion to obtain the product 2,5-dihydroxybenzaldehyde with higher purity under the conditions of mild reaction conditions and short reaction route.
Detailed Description
The technical solutions in the embodiments of the present invention are clearly and completely described below, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
1) Synthesis of 2-hydroxy-5-methoxybenzaldehyde:
adding 70g of p-hydroxyanisole and 3500g of acetonitrile into a 1L three-necked bottle, dissolving, adding 80g of magnesium chloride in batches, dropping 114g of triethylamine, controlling the temperature of the system to be about 62 ℃, adding 51g of paraformaldehyde in batches, naturally heating to reflux 75 ℃, reacting for 4 hours, pouring the reaction liquid into 2M hydrochloric acid, extracting with toluene, drying, and concentrating to obtain 76g of dark brown oily liquid;
2) synthesis of 2, 5-dihydroxybenzaldehyde:
adding toluene 1322g and 2-hydroxy-5-methoxybenzaldehyde 76g into a 2L three-necked bottle, adding aluminum trichloride 150g, heating for reflux reaction for 4h, pouring the reaction liquid into 2M hydrochloric acid, extracting with toluene, separating liquid, drying with anhydrous sodium sulfate 20g, adding activated carbon 20g, stirring under reflux for 1h, cooling to 20 ℃, adding diatomite, filtering, leaching with toluene 200ml, concentrating, recrystallizing with dichloromethane, and drying to obtain 2,5-dihydroxybenzaldehyde 44g with LC content of 99.9%.
Example 2
1) Synthesis of 2-hydroxy-5-methoxybenzaldehyde:
adding 700g of p-hydroxyanisole and 3500g of acetonitrile into a 10L three-necked bottle for dissolving, then adding 800g of magnesium chloride in batches, dropping 1140g of triethylamine, controlling the temperature of the system to be about 60 ℃, adding 510g of paraformaldehyde in batches, naturally raising the temperature to reflux 75 ℃, reacting for 4 hours, pouring the reaction liquid into 2M hydrochloric acid, extracting with toluene, drying, and concentrating to obtain 760g of dark brown oily liquid;
2) synthesis of 2, 5-dihydroxybenzaldehyde:
13220g of toluene and 760g of 2-hydroxy-5-methoxybenzaldehyde are added into a 20L three-necked bottle, 1500g of aluminum trichloride is added, the temperature is increased and the reflux reaction is carried out for 4h, the reaction liquid is poured into 2M hydrochloric acid, 2L of toluene is used for extraction, liquid separation is carried out, 200g of anhydrous sodium sulfate is dried, 200g of activated carbon is added, the reflux stirring is carried out for 1h, the temperature is reduced to 20 ℃, diatomite is added for filtration, 2L of toluene is used for drip washing, concentration is carried out, the crude product is recrystallized by dichloromethane, and drying is carried out, 440g of 2,5-dihydroxybenzaldehyde is obtained, and the content LC.
The above description is only a preferred embodiment of the present invention, and not intended to limit the present invention, and the scope of the present invention is defined by the appended claims, and all changes that come within the meaning and range of equivalency of the specification are therefore intended to be embraced therein.
Claims (4)
1. A preparation method of 2,5-dihydroxy benzaldehyde is characterized in that p-methoxyphenol is taken as a raw material, formylation reaction and demethylation reaction are carried out in sequence to obtain 2,5-dihydroxy benzaldehyde, the reaction equation is as follows,
the specific preparation steps of the 2,5-dihydroxy benzaldehyde are as follows:
s1, formylation, namely reacting p-methoxyphenol serving as a raw material, alkyl nitrile serving as a solvent, paraformaldehyde serving as a formylation reagent, magnesium chloride and triethylamine serving as catalysts for 2-4 hours, extracting a reaction liquid by using an organic solvent, washing by using water, drying, and evaporating to remove the solvent to obtain liquid 2-hydroxy-5-methoxybenzaldehyde, wherein the mass ratio of the alkyl nitrile to the p-methoxyphenol is 3-10: 1; the molar ratio of paraformaldehyde to p-methoxyphenol is 1-3: 1; the molar ratio of the magnesium chloride to the p-methoxyphenol is 1-3: 1; the molar ratio of triethylamine to p-methoxyphenol is 1-3: 1;
s2, demethylation reaction: taking methylbenzene as a solvent, and carrying out demethylation reaction on the 2-hydroxy-5-methoxybenzaldehyde obtained in the step S1 under the action of anhydrous aluminum trichloride to obtain 2, 5-dihydroxybenzaldehyde; the mass ratio of the toluene to the 2-hydroxy-5-methoxybenzaldehyde is 10-20: 1; the molar ratio of aluminum trichloride to 2-hydroxy-5-methoxybenzaldehyde is 1-3: 1, the reaction is carried out for 2-4 hours, the reaction liquid is washed by water, extracted by an organic solvent, dried, evaporated to remove the solvent, and crystallized by the solvent.
2. The process according to claim 1, wherein the alkylnitrile used in step S1 is acetonitrile.
3. The method of claim 1, wherein the organic solvent used in steps S1 and S2 is one or more selected from toluene, methyl tert-ether, dichloromethane, and dichloroethane.
4. The method of claim 1, wherein the solvent used in the solvent crystallization of step S2 comprises one or more of dichloromethane, dichloroethane, petroleum ether, and methanol.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110310683.0A CN113121325A (en) | 2021-03-23 | 2021-03-23 | Preparation method of 2,5-dihydroxy benzaldehyde |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110310683.0A CN113121325A (en) | 2021-03-23 | 2021-03-23 | Preparation method of 2,5-dihydroxy benzaldehyde |
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4151201A (en) * | 1976-08-13 | 1979-04-24 | Montedison S.P.A. | Process for preparing 2-hydroxybenzoic aldehydes |
| JP2013199455A (en) * | 2012-03-26 | 2013-10-03 | Nippon Zeon Co Ltd | Method for producing 2,5-dihydroxy benzaldehyde compound |
| CN110330417A (en) * | 2019-08-17 | 2019-10-15 | 江西力田维康科技有限公司 | The preparation method of 2,5- 4-dihydroxy benzaldehyde |
| CN110343209A (en) * | 2019-07-15 | 2019-10-18 | 中国科学院青岛生物能源与过程研究所 | A kind of two teeth phosphorus ligand polymer and preparation method thereof and the application in hydroformylation of olefin |
-
2021
- 2021-03-23 CN CN202110310683.0A patent/CN113121325A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4151201A (en) * | 1976-08-13 | 1979-04-24 | Montedison S.P.A. | Process for preparing 2-hydroxybenzoic aldehydes |
| JP2013199455A (en) * | 2012-03-26 | 2013-10-03 | Nippon Zeon Co Ltd | Method for producing 2,5-dihydroxy benzaldehyde compound |
| CN110343209A (en) * | 2019-07-15 | 2019-10-18 | 中国科学院青岛生物能源与过程研究所 | A kind of two teeth phosphorus ligand polymer and preparation method thereof and the application in hydroformylation of olefin |
| CN110330417A (en) * | 2019-08-17 | 2019-10-15 | 江西力田维康科技有限公司 | The preparation method of 2,5- 4-dihydroxy benzaldehyde |
Non-Patent Citations (4)
| Title |
|---|
| HOFSLOKKEN NU.等: "Convenient method for the ortho-formylation of phenols", 《ACTA CHEMICA SCANDINAVICA》 * |
| PASSINIEMI MIKKO等: "Demethylation of aromatic methyl ethers using ionic liquids under microwave irradiation", 《LETTERS IN ORGANIC CHEMISTRY》 * |
| ROBERT ALDRED等: "Magnesium-mediated ortho-Specific Formylation and Formaldoximation of Phenols", 《J.CHEM.SOC.，PERKIN TRANSACTIONS 1》 * |
| SOLEIMANI EBRAHIM等: "MgBr2 supported on Fe3O4@SiO2 urea nanoparticle: An efficient catalyst for ortho-formylation of phenols and oxidation of benzylic alcohols", 《APPLIED ORGANOMETALLIC CHEMISTRY》 * |
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Application publication date: 20210716 |