CN104478645A - Preparation method of 2-vinyl naphthalene compound - Google Patents
Preparation method of 2-vinyl naphthalene compound Download PDFInfo
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- CN104478645A CN104478645A CN201410792869.4A CN201410792869A CN104478645A CN 104478645 A CN104478645 A CN 104478645A CN 201410792869 A CN201410792869 A CN 201410792869A CN 104478645 A CN104478645 A CN 104478645A
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- KXYAVSFOJVUIHT-UHFFFAOYSA-N C=Cc1cc(cccc2)c2cc1 Chemical compound C=Cc1cc(cccc2)c2cc1 KXYAVSFOJVUIHT-UHFFFAOYSA-N 0.000 description 1
- XSAYZAUNJMRRIR-UHFFFAOYSA-N CC(c1cc(cccc2)c2cc1)=O Chemical compound CC(c1cc(cccc2)c2cc1)=O XSAYZAUNJMRRIR-UHFFFAOYSA-N 0.000 description 1
- AXRKCRWZRKETCK-VIFPVBQESA-N C[C@@H](c1cc2ccccc2cc1)O Chemical compound C[C@@H](c1cc2ccccc2cc1)O AXRKCRWZRKETCK-VIFPVBQESA-N 0.000 description 1
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Abstract
The invention relates to a preparation method of a 2-vinyl naphthalene compound. The preparation method comprises the following steps: step (1), reducing a carbonyl group of 2-acetyl-naphthalene as a raw material into a hydroxyl group in an alcohol solvent to obtain an intermediate; and step (2), in the presence of a polymerization inhibitor and a catalyst, dehydrating the hydroxyl group to obtain a vinyl group, wherein the dehydrating step comprises the specific following steps: evenly mixing the catalyst, the intermediate obtained in the step (1) and the polymerization inhibitor in a preheating tank to obtain a mixture, adding the mixture into a reactor I and reacting, further reacting in a reactor II, condensing a gaseous product into a liquid product in a condenser, and preparing the finished product from a receiver tank, wherein the degree of vacuum is maintained at 0.1-2mmHg. The preparation method provided by the invention has the advantages of easily available raw materials, high yield, less side reaction, simple needed device and no need of high temperature and pressure conditions. Moreover, the preparation method is suitable for industrial enlarged production of the 2-vinyl naphthalene compound.
Description
Technical field
The present invention relates to organic synthesis field, particularly relate to a kind of preparation method of 2-vinyl naphthalene compound.
Background technology
Vinyl naphthalene (vinylnaphthalene) is the intermediate of synthesis of vinyl naphthalene polymkeric substance.Because it contains active vinyl, vinyl naphthalene widespread use can make medicine intermediate, dyestuff intermediate and optical element coating material etc.2-vinyl naphthalene can be given high heat-resisting to various high molecular polymer, low-k, low-dielectric loss, high refractive index, the features such as difficult combustion and agent of low hygroscopicity.As: polym.Eng.Sci., 33 (9), 549-58 (1993) and Macromolecules., discloses vinylbenzene and the copolymerization of 2-vinyl naphthalene and Tg is improve about 15 degree in 29 (10), 620-6245 (1996).
Patent publication No.: report in CN101248391 that vinyl naphthalene can prevent anti-etching figure the subsiding after development of the granular with anti-etching figure as modular construction gained coated substance.
The method of existing synthesis of vinyl naphthalene is as follows:
US5087769 discloses the synthetic method of-2-vinyl naphthalene that 6-replaces, and its raw material is 2 acyl-naphthalines be substituted, and its raw material has related to by shortening, restored the preparation method that dehydration obtains 2-vinyl naphthalene compound.Though can obtain product under this reaction conditions, its processing condition are harsh, processing requirement is complicated, operation easier is larger.
US5191133 carries out the technique that shortening, again processed obtain 2-vinyl naphthalene compound under disclosing and taking condition of high voltage.
Also ethyl naphthalene direct dehydrogenation is obtained by reacting vinyl naphthalene in Unexamined Patent 06-138985 publication.The method reaction raw materials and product are all more single, and to production technology, catalyst activity requires very high, is not suitable for general chemical enterprise.
And the method for some literature periodicals report mostly aftertreatment difficulty after expensive starting materials, be more not suitable for production method.As: Selective Arylation and Vinylation at the α Position of Vinylarenes By Zou, yinjun te al from Chemistry-A European Journal 19 (10), 3504-3511; 2013 reports react with 2-bromonaphthalene and F3BCH2CH2 to be prepared.The method expensive starting materials, aftertreatment trouble is not suitable for industrial production; Low pressure vinylation of aryl and vinyl halides via Heck-Mizoroki reactions Using ethylene by smith; Craig R and RajanBabu, T.V. From Tetrahedron 66 (5) 1102-1110; 2010 react with 2-bromonaphthalene and CH2CH2, and this reaction preference is bad, require high to catalyst activity.
In prior art, the facile syntheesis technique of vinyl naphthalene lacks, and existing processing condition are harsh, processing requirement is complicated, and products obtained therefrom also exists the shortcomings such as foreign matter content is comparatively large, product yield is low, product content is low.Therefore, the improvement of the synthesis technique of vinyl naphthalene is significant.
Summary of the invention
For problems of the prior art, the object of this invention is to provide the preparation method of a kind of 2-vinyl naphthalene compound mainly 2-vinyl naphthalene.Described preparation method's raw material is easy to get, technique is simple, easy and simple to handle, and there is the high advantage of the low and productive rate of cost.
The invention provides a kind of preparation method of 2-vinyl naphthalene compound, the method comprises the following steps: be raw material by 2 acetyl naphthalene, is hydroxyl, then by hydroxyls dehydrate, obtains final product carbonyl reduction.
Concrete, said method comprising the steps of:
(1) be raw material with 2 acetyl naphthalene, be dissolved in alcoholic solvent, add reductive agent, carry out reduction reaction; Adding acid regulates reaction solution pH to 6-8 to separate out solid, obtains product intermediate;
(2) by products obtained therefrom intermediate in step (1), with catalyzer, stopper mixing preheating, carries out dehydration reaction and obtains product;
(3) recrystallization is carried out to step (2) gained crude product.
In aforesaid method:
In described step (1):
Described alcoholic solvent is methyl alcohol or aqueous ethanolic solution.
The consumption of alcoholic solvent is 3.33 times of raw material weight.
Described reductive agent is sodium borohydride, POTASSIUM BOROHYDRIDE or lithium aluminum hydride, and the mol ratio of described reductive agent and raw material is 1:0.25-1:0.45.
The temperature of described reduction reaction is 10-40 DEG C, and the reaction times is 2-3 h.
The described pH value adding acid adjustment reaction solution, described acid is hydrochloric acid, and described aqueous acid massfraction is 5-15%.
Through aftertreatment purification operations before described step (1) and (2): products obtained therefrom intermediate being joined quality is dissolve in its toluene of 2 times, leave standstill 30min layering and get upper organic phase, it is then concentrated that (maintenance temperature more than 70 degree carries out concentrating under reduced pressure, concentrate to obtain the product intermediate of molten, concentrating under reduced pressure is raised the efficiency) organic phase solution, then crystallisation by cooling.
In described step (2):
In fore-warmer tank, intermediate heating and melting is complete, and the temperature of heating is not less than 120 degree, adds stopper again, catalyzer after thawing
Described stopper is 4-methoxyphenol, Resorcinol, stopper 168, copper sulfate, and the mass ratio of described stopper and product intermediate is 10-5:1-0.01:1.
Described catalyzer is sal enixum, and the mol ratio of described catalyzer and product intermediate is 0.05:1-0.1:1.
The dehydration reaction time is 1-5 h, by controlling the joining day adjusting reaction time of material.In reaction process, vacuum tightness maintains 0.1 ~ 2mmHg.
In described step (3):
Ethanol consumption is 2.5 times of crude product weight.
The preparation method of 2-vinyl naphthalene compound provided by the present invention has the following advantages.
Raw material is easy to get, technique is simple, easy and simple to handle, and it is high to have the low and productive rate of cost, the advantage that products obtained therefrom purity is high.
Compared with the preparation method existed in prior art, preparation method of the present invention is without the need to using the processing condition of the harshnesses such as high pressure, and products obtained therefrom productive rate is high and foreign matter content is few, can conveniently be effectively applied in the production of 2-vinyl naphthalene compound.
Embodiment
Following examples for illustration of the present invention, but are not used for limiting the scope of the invention.
The invention provides a kind of preparation method of 2-vinyl naphthalene compound, is raw material by 2 acetyl naphthalene, and by being hydroxyl by carbonyl reduction, then the method obtaining vinyl by hydroxyls dehydrate prepares 2-vinyl naphthalene compound.
Wherein, described preparation method comprises the following steps:
(1) be raw material with 2 acetyl naphthalene, be dissolved in alcoholic solvent, add reductive agent, at 10 ~ 40 DEG C, carry out reduction reaction 2 ~ 3 h.Described reductive agent is sodium borohydride, POTASSIUM BOROHYDRIDE or lithium aluminum hydride, and the mol ratio of described reductive agent and raw material is 1:0.25 ~ 1:0.45; Described alcoholic solvent is methyl alcohol, aqueous ethanolic solution.After reaction, by adding aqueous acid, regulating reaction solution pH to 6-8 to separate out solid, obtaining product intermediate, it is that its toluene of 2 times dissolves that products obtained therefrom intermediate adds quality, and stratification gets upper organic phase, concentrated organic phase solution, crystallisation by cooling.Wherein said aqueous acid massfraction is 5 ~ 15%; The preferred hydrochloric acid of described acid.
(2) after complete for middle for step (1) products obtained therefrom intermediate heating and melting, stopper and catalyzer is added, be preheated to 120 ~ 130 DEG C and carry out dehydration reaction by reaction unit I, II, in reaction, water byproduct is directly removed by vacuum, depart from reaction system, the dehydration reaction time is 1 ~ 5 h.Described stopper is 4-methoxyphenol, Resorcinol, stopper 168, copper sulfate, and the mass ratio of described stopper and product intermediate is 10-5:1 ~ 10-2:1; Described catalyzer is sal enixum, and the mol ratio of described catalyzer and product intermediate is 0.1:1 ~ 0.05:1.
(3) products obtained therefrom in step (2) is carried out recrystallization, solvent adds 2.5 times that quality amount is crude product.
Embodiment 1
10 kg methyl alcohol are joined in the reactor with cold cooling unit, adds the 2 acetyl naphthalene of 3 kg to it, open stirring and make it dissolve, until it dissolves completely.Reacting liquid temperature is down to 10 DEG C, adds sodium borohydride 2.67 kg and reduce, keep temperature of reaction about 10 DEG C reaction 2 h.Monitor reaction solution in real time with TLC, determine wherein without stopped reaction after starting material left, in still, add the hydrochloric acid soln that massfraction is 10%, regulation system pH to 7, separate out solid, centrifugal product intermediate 2-hydroxyethyl naphthalene crude product.Be its toluene heating for dissolving of 2 times by products obtained therefrom crude intermediate quality, stratification, separatory removes aqueous phase, is concentrated by gained organic phase solution, after completing, molten product is placed in pallet and cools to obtain product intermediate at 70 DEG C.Be heating and melting during the product intermediate of 7200 parts adds with heating and stirring device fore-warmer tank again by parts by weight, to add parts by weight after melting be completely the 4-methoxyphenol of 20 parts and parts by weight is the sal enixum of 56 parts.By regulating into speed, material is reacted in 1h by reactor.Reactor I set temperature 135 degree, temperature of reactor arranges 120 degree, condensate temperature 70 degree.Obtain the product crude product that yield is 88% after reaction, wherein 2-vinyl naphthalene content is 95%.In the receiving tank of function to be heated, directly add the anhydrous alcohol solution of 2.5 times, recrystallization.Finally obtain product, total recovery is that 79%, product G C purity reaches 99.1%.
Embodiment 2
11 kg95% ethanol are joined in cold cooling unit reactor to be had, adds the 2 acetyl naphthalene of 3kg to it, open stirring and make it dissolve, until it dissolves completely.Reacting liquid temperature is down within 10 DEG C, adds POTASSIUM BOROHYDRIDE 1.483 kg and reduce, within keeping temperature of reaction 10 DEG C, continue reaction 3 h.Monitor reaction solution in real time with TLC, determine wherein without stopped reaction after starting material left, in still, add the hydrochloric acid soln that massfraction is 10%, regulation system pH to 7, separate out product, centrifugal product intermediate 2-hydroxyethyl naphthalene crude product.Be its toluene heating for dissolving of 2 times by products obtained therefrom crude intermediate quality, stratification, separatory removes aqueous phase, is concentrated by gained organic phase solution, after completing, molten product is placed in pallet and cools to obtain product intermediate at 70 DEG C.Be that the product intermediate of 7200 parts adds heating and melting in the reactor of band heated and stirred again by parts by weight, to add parts by weight after melting be completely the Resorcinol of 18 parts and parts by weight is the sal enixum of 32 parts.By regulating into speed, material is reacted in 1h by reactor.Reactor I set temperature 140 degree, temperature of reactor arranges 125 degree, condensate temperature 70 degree.Obtain the product crude product that yield is 86% after reaction, wherein 2-vinyl naphthalene content is 94.5%.In the receiving tank of function to be heated, directly add the anhydrous alcohol solution of 2.5 times, recrystallization.Finally obtain product, total recovery is that 77%, product G C purity reaches 99.0%.
Embodiment 3
10 kg methyl alcohol are joined in the reactor with cold cooling unit, adds the 2 acetyl naphthalene of 3 kg to it, open stirring and make it dissolve, until it dissolves completely.Reacting liquid temperature is adjusted to 40 DEG C, adds sodium borohydride 1.483 kg and reduce, keep temperature of reaction about 40 DEG C reaction 3 h.Monitor reaction solution in real time with TLC, determine wherein without stopped reaction after starting material left, in still, add the hydrochloric acid soln that massfraction is 10%, regulation system pH to 7, separate out solid, centrifugal product intermediate 2-hydroxyethyl naphthalene crude product.Be its toluene heating for dissolving of 2 times by products obtained therefrom crude intermediate quality, stratification, separatory removes aqueous phase, is concentrated by gained organic phase solution, after completing, molten product is placed in pallet and cools to obtain product intermediate at 70 DEG C.Be heating and melting during the product intermediate of 7200 parts adds with heating and stirring device reactor again by parts by weight, to add parts by weight after melting be completely the stopper 168 of 0.072 part and parts by weight is the sal enixum of 428 parts.By regulating into speed, material is reacted in 1h by reactor.Reactor I set temperature 130 degree, temperature of reactor arranges 120 degree, condensate temperature 70 degree.Obtain the product crude product that yield is 84% after reaction, wherein 2-vinyl naphthalene content is 95.5%.In the receiving tank of function to be heated, directly add the anhydrous alcohol solution of 2.5 times, recrystallization.Finally obtain product, total recovery is that 78%, product G C purity reaches 99.2%.
Embodiment 4
60 kg methyl alcohol are joined in the reactor with cold cooling unit, adds the 2 acetyl naphthalene of 18 kg to it, open stirring and make it dissolve, until it dissolves completely.Reacting liquid temperature is adjusted to 40 DEG C, adds sodium borohydride 12.72 kg and reduce, keep temperature of reaction about 40 DEG C reaction 3 h.Monitor reaction solution in real time with TLC, determine wherein without stopped reaction after starting material left, in still, add the hydrochloric acid soln that massfraction is 10%, regulation system pH to 7, separate out solid, centrifugal product intermediate 2-hydroxyethyl naphthalene crude product.Be its toluene heating for dissolving of 2 times by products obtained therefrom crude intermediate quality, stratification, separatory removes aqueous phase, is concentrated by gained organic phase solution, after completing, molten product is placed in pallet and cools to obtain product intermediate at 70 DEG C.Be heating and melting during the product intermediate of 10800 parts adds with heating and stirring device reactor again by parts by weight, to add parts by weight after melting be completely the stopper 168 of 0.12 part and parts by weight is the sal enixum of 60 parts.By regulating into speed, material is reacted in 4h by reactor.Reactor I set temperature 135 degree, temperature of reactor arranges 125 degree, condensate temperature 70 degree.Obtain the product crude product that yield is 89% after reaction, wherein 2-vinyl naphthalene content is 95.3%.In the receiving tank of function to be heated, directly add the anhydrous alcohol solution of 2.5 times, recrystallization.Finally obtain product, total recovery is that 80%, product G C purity reaches 99.1%.
Although above with general explanation, embodiment and test, the present invention is described in detail, and on basis of the present invention, can make some modifications or improvements it, this will be apparent to those skilled in the art.Therefore, these modifications or improvements without departing from theon the basis of the spirit of the present invention, all belong to the scope of protection of present invention.
Claims (11)
1. a preparation method for 2-vinyl naphthalene compound, is characterized in that, take 2 acetyl naphthalene as raw material, by being hydroxyl by carbonyl reduction, preparing 2-vinyl naphthalene compound by the method for hydroxyls dehydrate again, reaction equation:
。
2. preparation method according to claim 1, is characterized in that, described preparation method comprises the following steps:
(1) be raw material with 2 acetyl naphthalene, be dissolved in alcoholic solvent, add reductive agent, carry out reduction reaction, add acid and regulate reaction solution pH to 6-8 to separate out solid, obtain product intermediate;
(2) by products obtained therefrom intermediate in step (1), with catalyzer, stopper mixing preheating, carries out dehydration reaction and obtains product;
(3) products obtained therefrom is through dehydrated alcohol recrystallization, improves crude product purity.
3. preparation method according to claim 2, is characterized in that, in described step (1), reductive agent is sodium borohydride, POTASSIUM BOROHYDRIDE or lithium aluminum hydride, and the mol ratio of described reductive agent and raw material is 1:0.25 ~ 1:0.45.
4. the preparation method according to Claims 2 or 3, is characterized in that, in described step (1) alcoholic solvent be methyl alcohol, ethanol or 95% aqueous ethanolic solution; Described reduction reaction temperature is 10 ~ 40 DEG C, and the reaction times is 2 ~ 3 h.
5. preparation method according to claim 2, is characterized in that, regulate the pH value of reaction solution in described step (2) by adding aqueous acid, described aqueous acid massfraction is 5 ~ 15%; The preferred hydrochloric acid of described acid.
6. the preparation method according to claim 2 or 5, it is characterized in that, described step (1) products obtained therefrom intermediate is carrying out step (2) before through aftertreatment purification operations: it is that its toluene of 2 times dissolves that products obtained therefrom intermediate adds quality, stratification gets upper organic phase, concentrated organic phase solution, crystallisation by cooling obtains intermediate.
7. preparation method according to claim 2, is characterized in that, in described step (2), stopper is 4-methoxyphenol, Resorcinol, stopper 168, copper sulfate, and the weight ratio of described stopper and product intermediate is 10-5:1 ~ 10-2:1.
8. the preparation method according to claim 2 or 7, is characterized in that, in described step (2), catalyzer is sal enixum, and the mol ratio of described catalyzer and product intermediate is 0.005:1 ~ 0.1:1.
9. preparation method according to claim 8, is characterized in that, in described step (2), the dehydration reaction time is 1 ~ 5h.
10. preparation method according to claim 2, is characterized in that, in described step (2), fore-warmer tank temperature is 120 ~ 130 degree, and reactor I temperature is 130 ~ 140 degree, and reactor II temperature is 120 ~ 125 degree, and in reaction process, vacuum tightness maintains 0.1 ~ 2mmHg.
Recrystallization ethanol in 11. steps (3): crude product weight ratio is: 1:2.5.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106187658A (en) * | 2016-07-25 | 2016-12-07 | 海门德思行药业科技有限公司 | A kind of preparation method of 2 vinyl naphthalenes |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101747162A (en) * | 2009-12-25 | 2010-06-23 | 南京工业大学 | Synthesis process of p-methoxystyrene |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101747162A (en) * | 2009-12-25 | 2010-06-23 | 南京工业大学 | Synthesis process of p-methoxystyrene |
Non-Patent Citations (2)
| Title |
|---|
| Y. BENITO ET AL.,: "SYNTHESIS AND POLYMERIZATION OF 2-VINYLQUINOLINE AND 2-VINYLNAPHTHALENE WITH A1Et3-VCI3: INFLUENCE OF PYRIDINE AS DONOR LIGAND", 《EUR. POLYM. J.》 * |
| 何明阳等: "对氟苯乙烯的合成", 《石油化工》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106187658A (en) * | 2016-07-25 | 2016-12-07 | 海门德思行药业科技有限公司 | A kind of preparation method of 2 vinyl naphthalenes |
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