CN105294433B - A kind of synthetic method of gallic acid lower alkyl alcohol ester - Google Patents
A kind of synthetic method of gallic acid lower alkyl alcohol ester Download PDFInfo
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- CN105294433B CN105294433B CN201510606215.2A CN201510606215A CN105294433B CN 105294433 B CN105294433 B CN 105294433B CN 201510606215 A CN201510606215 A CN 201510606215A CN 105294433 B CN105294433 B CN 105294433B
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- gallic acid
- lower alkyl
- sulfonate resin
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- alcohol
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- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/08—Preparation of carboxylic acid esters by reacting carboxylic acids or symmetrical anhydrides with the hydroxy or O-metal group of organic compounds
Abstract
A kind of synthetic method of gallic acid lower alkyl alcohol ester, comprises the following steps：（1）Gallic acid and low-grade alkane alcohol are placed in reactor, add hydrophobically modified azochlorosulfonate acid resin catalyst, is stirred, is warming up to 65~120 DEG C, 4~10 h is reacted, filtering, obtains filtrate；（2）By step（1）Excessive alcohol is evaporated off in gained filtrate, obtains crude product, then is recrystallized with deionized water, filters, and dries, obtains gallic acid lower alkyl alcohol ester.Synthetic method of the present invention is simple, safe operation, the % of gallic acid lower alkyl alcohol ester yield >=92, the % of product purity >=99.5, and catalyst performance is excellent, reduces in conventional method and divides water ring section, simplifies reaction unit, has preferable Repeatability.
Description
Technical field
The present invention relates to a kind of synthetic method of gallic acid lower alkyl alcohol ester, and in particular to a kind of sulfonic acid of hydrophobically modified
The method of resin catalysis synthesizing gallic acid lower alkyl alcohol ester.
Background technology
Gallic acid lower alkyl alcohol ester is the food antioxidant of a kind of low cost, have antibacterial, anti-platelet aggregation with
And increase blood fluidity isoreactivity.The synthesis of gallic acid lower alkyl alcohol ester is typically by sulphuric acid catalysis gallic acid and low
Level alkanol occurs esterification and is made, but Strong oxdiative due to the concentrated sulfuric acid and deep-etching effect, to product quality, equipment requirement with
And post-reaction treatment etc. brings inconvenience.
Traditional homogeneous catalyst is replaced to solve the above problems with solid acid catalyst, wherein, sulfonate resin is exactly
The conventional solid acid catalyst of one kind.In recent years, the synthesis for being catalyzed gallic acid lower alkyl alcohol ester using sulfonate resin also has one
A little reports, such as poplar height text etc.（Yang Gaowen, Zeng little Jun, Zhou Jinxin storng-acid cation exchange resins, which catalyze and synthesize, not to be eaten
Sub- propyl propionate [J] Speciality Petrochemicals progress, 2003,4 (7): 7-9.）Report using sulfonate resin D72, D61 and
D001-CC catalyzes and synthesizes to have obtained propylgallate, but its yield only up to reach 80 % or so, and resin passes through 6
After secondary reuse, products collection efficiency is less than 20 %, and esterification reaction process occurs mainly due to gallic acid and low-grade alkane alcohol in this
It is middle can be with the generation of water.Although influence of the water to reaction balance can be reduced by introducing water knockout drum, divide water can not be fully by water
Discharge, the water of residual can still destroy the activated centre on sulfonate resin, moreover, under heating condition, water can promote sulfonate resin
Upper part sulfonic group hydrolyzes, so as to reduce the catalytic activity of sulfonate resin and recycling efficiency.Existing for prior art
These problems, limit application of the sulfonate resin on gallic acid low-grade alkane alcohol Lipase absobed.
The content of the invention
The technical problems to be solved by the invention are to overcome drawbacks described above existing for prior art, there is provided a kind of method letter
It is single, the synthetic method of the high gallic acid lower alkyl alcohol ester of product yield, purity.
The technical solution adopted for the present invention to solve the technical problems is as follows：A kind of synthesis of gallic acid lower alkyl alcohol ester
Method, comprise the following steps：
（1）Gallic acid and low-grade alkane alcohol are placed in reactor, hydrophobically modified azochlorosulfonate acid resin catalyst is added, stirs
Mix, be warming up to 65~120 DEG C, react 4~10 h, filtering, obtain filtrate；
（2）By step（1）Excessive alcohol is evaporated off in gained filtrate, obtains crude product, then is recrystallized with deionized water, filters,
Dry, obtain gallic acid lower alkyl alcohol ester.
Further, step（1）In, the matter of the azochlorosulfonate acid resin catalyst of the gallic acid, low-grade alkane alcohol and hydrophobically modified
Amount is than being 1:1.0~4.5:0.2~0.5.Because low-grade alkane alcohol is both reaction raw materials in the reaction, dissolving gallic acid is played again
Effect, therefore addition should be more than gallic acid, and react using the sulfonate resin of hydrophobically modified as catalyst, if low-grade alkane alcohol adds
It is excessive to enter amount, gallic acid concentration in reaction solution can be caused to reduce, and reduces the collision that gallic acid contacts with resin catalyst
Probability, so as to which the catalytic performance of resin can be influenceed.
Further, step（1）In, the styrene obtained by halogenation occurs for phenyl ring for the sulfonate resin of the hydrophobically modified
It is sulfonate resin.The halogenation is chlorination, bromination or iodination reaction, and the styrene obtained by bromination reaction occurs for preferably phenyl ring
It is sulfonate resin.The preferred resins of Amberlyst 15 of polystyrene sulfonate resin.
Further, step（1）In, the method for modifying of the azochlorosulfonate acid resin catalyst of the hydrophobically modified is：With halogen and benzene
The mass ratio of ethene system sulfonate resin is 0.6~1:1, halogen is added in polystyrene sulfonate resin and solvent, stirring, 50
At~60 DEG C, lucifuge is reacted to solution decolourization, filtering, is cleaned with water to neutrality, is obtained the sulfonate resin of hydrophobically modified；When the halogen
When element is iodine, concentrated nitric acid is added while adding iodine.The sulfonate resin of the hydrophobically modified can be commercially available, the preferred above method
Prepare the sulfonate resin of gained hydrophobically modified.Due to introducing hydrophobic halogen group after modification, resin hydrophobic activity is significantly
Enhancing, and because the electron attraction of halogen atom, the stability of sulfonic acid group greatly enhance, and then improve resin catalyst
Recycling efficiency.
Further, when the halogen is chlorine or bromine, the solvent is water；When the halogen is iodine, the solvent is
Glacial acetic acid.The solvent is only used as reaction medium, it is not necessary to limits specific dosage.
Further, the addition of the concentrated nitric acid is 5~10 % of polystyrene sulfonate resin quality.When the halogen is
During iodine, concentrated nitric acid is added simultaneously in the iodination reaction of the polystyrene sulfonate resin, is because the oxidable iodine list of concentrated nitric acid
I of the matter generation with stronger nucleophilicity+Ion, so that the iodination reaction of resin is smoothed out.The quality of the concentrated nitric acid point
Number is 50~70 %.
Further, step（1）In, the low-grade alkane alcohol is the saturated monohydroxy alcohol of carbon number≤6.The carbon number≤
6 saturated monohydroxy alcohol is methanol, ethanol, normal propyl alcohol, isopropanol, n-butanol, n-amyl alcohol or n-hexyl alcohol etc..
Step（1）In, the azochlorosulfonate acid resin catalyst of gained hydrophobically modified is recyclable after filtering is reused.
Step（2）In, it is described to be evaporated off, using being evaporated under reduced pressure, being to remove low-grade alkane alcohol, distilling using conventional method
To dry crude product, without special limited reactions condition.
Step（2）In, after excessive alcohol is evaporated off, the purpose recrystallized with deionized water is to be further purified.
The inventive method is that the sulfonate resin of halogenation occurs as catalyst using phenyl ring, by gallic acid and excessive low
Esterification occurs under level alkanol heating condition.Due to introducing hydrophobic halogen group to resin phenyl ring, resin is improved
Hydrophobic active and sulfonic stability, and then influence of the water to resin catalysis activity and stability is reduced, final synthesis does not have
Gallate-based lower alkyl alcohol ester, such as gallicin, progallin A, n -Propyl gallate, isopropyl gallate, do not have
Gallate-based N-butyl, Isobutyl gallate, n-Amyl gallate or gallic acid etc..
Compared with prior art, the inventive method has advantages below：
（1）Phenyl ring used in the inventive method passes through the azochlorosulfonate acid resin catalyst function admirable of halogenation modification, reduces
Divide water ring section in conventional method, simplify reaction unit；
（2）Phenyl ring used in the inventive method by the sulfonate resin of halogenation modification after 5 repetition Catalysis experiments,
Products collection efficiency rate of descent is only 3~13 %, and catalyst recovery yield only declines 4~10 %, has preferable Repeatability；
（3）Synthetic method of the present invention is simple, safe operation, the % of gallic acid lower alkyl alcohol ester yield >=92, product purity
≥99.5 %。
Embodiment
With reference to embodiment, the invention will be further described.
The resins of Amberlyst 15 are purchased from ROHM AND HAAS used in reference example of the present invention（Shanghai）Company；The present invention is implemented
Chemical reagent used in example, unless otherwise specified, is obtained by routine business approach.
Reference example 1
The preparation method of chlorination modified sulfonate resin：
The resins of 20 g Amberlyst 15 and 60 mL distilled water are placed in reaction bulb, then pass to 12 g chlorine, electricity
Dynamic stirring, lucifuge is reacted to solution decolourization at 50 DEG C, filtering, is cleaned with water to neutrality, is obtained chlorination modified sulfonate resin.
Reference example 2
The preparation method for the sulfonate resin that bromination is modified：
The resins of 20 g Amberlyst 15 and 60 mL distilled water are placed in reaction bulb, then add 14 g bromines, electricity
Dynamic stirring, lucifuge is reacted to solution decolourization at 60 DEG C, filtering, is cleaned with water to neutrality, obtains the sulfonate resin of bromination modification.
Reference example 3
The preparation method for the sulfonate resin that iodate is modified：
The resins of 20 g Amberlyst 15 and 60 mL glacial acetic acid are placed in reaction bulb, then add 20 g iodine and 2 g
Concentrated nitric acid（Mass fraction is 69 %）, electric stirring, lucifuge is reacted to solution decolourization at 60 DEG C, filtering, is cleaned with water into
Property, obtain the sulfonate resin that iodate is modified.
Embodiment 1
（1）Weigh 100 g gallic acids and 100 g methanol are placed in reactor, add the gained chlorination of 40 g reference examples 1 and change
Property sulfonate resin, electric stirring, be warming up to 65 DEG C reaction 4 h, filtering, obtain filtrate, and reclaim chlorination modified sulfonate resin；
（2）By step（1）Excessive alcohol is evaporated off in gained filtrate, obtains crude product, then is recrystallized with deionized water, filters,
Dry, obtain gallicin, yield is 95 %, and product purity is 99.5 %.
Embodiment 2
（1）Weigh 100 g gallic acids and 100 g methanol are placed in reactor, add the gained bromination of 40 g reference examples 2 and change
Property sulfonate resin, electric stirring, be warming up to 65 DEG C reaction 4 h, filtering, obtain filtrate, and reclaim bromination modification sulfonate resin；
（2）By step（1）Excessive alcohol is evaporated off in gained filtrate, obtains crude product, then is recrystallized with deionized water, filters,
Dry, obtain gallicin, yield is 99 %, and product purity is 99.9 %.
Embodiment 3
（1）Weigh 100 g gallic acids and 100 g methanol are placed in reactor, add the gained iodate of 40 g reference examples 3 and change
Property sulfonate resin, electric stirring, be warming up to 65 DEG C reaction 4 h, filtering, obtain filtrate, and reclaim iodate modification sulfonate resin；
（2）By step（1）Excessive alcohol is evaporated off in gained filtrate, obtains crude product, then is recrystallized with deionized water, filters,
Dry, obtain gallicin, yield is 97 %, and product purity is 99.8 %.
Embodiment 4
（1）Weigh 100 g gallic acids and 150 g ethanol are placed in reactor, add the gained chlorination of 35 g reference examples 1 and change
Property sulfonate resin, electric stirring, be warming up to 80 DEG C reaction 5 h, filtering, obtain filtrate, and reclaim chlorination modified sulfonate resin；
（2）By step（1）Excessive alcohol is evaporated off in gained filtrate, obtains crude product, then is recrystallized with deionized water, filters,
Dry, obtain progallin A, yield is 92 %, and product purity is 99.8 %.
Embodiment 5
（1）Weigh 100 g gallic acids and 150 g ethanol are placed in reactor, add the gained bromination of 35 g reference examples 2 and change
Property sulfonate resin, electric stirring, be warming up to 80 DEG C reaction 5 h, filtering, obtain filtrate, and reclaim bromination modification sulfonate resin；
（2）By step（1）Excessive alcohol is evaporated off in gained filtrate, obtains crude product, then is recrystallized with deionized water, filters,
Dry, obtain progallin A, yield is 98 %, and product purity is 99.9 %.
Embodiment 6
（1）Weigh 100 g gallic acids and 150 g ethanol are placed in reactor, add what the iodate of 35 g reference examples 3 was modified
Sulfonate resin, electric stirring, 80 DEG C of 5 h of reaction are warming up to, filtering, obtain filtrate, and reclaim the sulfonate resin of iodate modification；
（2）By step（1）Excessive alcohol is evaporated off in gained filtrate, obtains crude product, then is recrystallized with deionized water, filters,
Dry, obtain progallin A, yield is 93 %, and product purity is 99.8 %.
Embodiment 7
（1）Weigh 100 g gallic acids and 200 g normal propyl alcohols are placed in reactor, add the gained bromination of 20 g reference examples 2
Modified sulfonate resin, electric stirring, 100 DEG C of 5 h of reaction are warming up to, filtering, obtain filtrate, and reclaim the sulfonic acid tree of bromination modification
Fat；
（2）By step（1）Excessive alcohol is evaporated off in gained filtrate, obtains crude product, then is recrystallized with deionized water, filters,
Dry, obtain n -Propyl gallate, yield is 98 %, and product purity is 99.9 %.
Embodiment 8
（1）Weigh 100 g gallic acids and 300 g isopropanols are placed in reactor, add the gained bromination of 30 g reference examples 2
Modified sulfonate resin, electric stirring, 85 DEG C of 7 h of reaction are warming up to, filtering, obtain filtrate, and reclaim the sulfonic acid tree of bromination modification
Fat；
（2）By step（1）Excessive alcohol is evaporated off in gained filtrate, obtains crude product, then is recrystallized with deionized water, filters,
Dry, obtain isopropyl gallate, yield is 94 %, and product purity is 99.8 %.
Embodiment 9
（1）Weigh 100 g gallic acids and 300 g n-butanols are placed in reactor, add the gained bromination of 25 g reference examples 2
Modified sulfonate resin, electric stirring, 120 DEG C of 5 h of reaction are warming up to, filtering, obtain filtrate, and reclaim the sulfonic acid tree of bromination modification
Fat；
（2）By step（1）Excessive alcohol is evaporated off in gained filtrate, obtains crude product, then is recrystallized with deionized water, filters,
Dry, obtain n butyl gallate, yield is 96 %, and product purity is 99.8 %.
Embodiment 10
（1）Weigh 100 g gallic acids and 350 g isobutanols are placed in reactor, add the gained bromination of 35 g reference examples 2
The sulfonate resin of hydrophobically modified, electric stirring, 110 DEG C of 8 h of reaction are warming up to, filtering, obtain filtrate, and reclaim the sulphur of bromination modification
Acid resin；
（2）By step（1）Excessive alcohol is evaporated off in gained filtrate, obtains crude product, then is recrystallized with deionized water, filters,
Dry, obtain Isobutyl gallate, yield is 94 %, and product purity is 99.8 %.
Embodiment 11
（1）Weigh 100 g gallic acids and 400 g n-amyl alcohols are placed in reactor, add the gained bromination of 40 g reference examples 2
Modified sulfonate resin, electric stirring, 135 DEG C of 8 h of reaction are warming up to, filtering, obtain filtrate, and reclaim the sulfonic acid tree of bromination modification
Fat；
（2）By step（1）Excessive alcohol is evaporated off in gained filtrate, obtains crude product, then is recrystallized with deionized water, filters,
Dry, obtain n-Amyl gallate, yield is 92 %, and product purity is 99.8 %.
Embodiment 12
（1）Weigh 100 g gallic acids and 450 g n-hexyl alcohols are placed in reactor, add the gained bromination of 50 g reference examples 2
The sulfonate resin of hydrophobically modified, electric stirring, 150 DEG C of 10 h of reaction are warming up to, filtering, obtain filtrate, and reclaim bromination modification
Sulfonate resin；
（2）By step（1）Excessive alcohol is evaporated off in gained filtrate, obtains crude product, then is recrystallized with deionized water, filters,
Dry, obtain gallic acid, yield is 92 %, and product purity is 99.8 %.
Comparative example 1
This comparative example technical scheme differs only in embodiment 4, step（1）In, by chlorination modified sulfonate resin
Replace with unmodified sulfonate resin Amberlyst 15.The yield of gained progallin A is 72 %.
In order to verify the repetition catalytic performance of used catalyst, spy carries out following test：
Repeat embodiment 4~6 and the process of the synthesizing gallic acid ethyl ester of comparative example 1（Experiment parameter, step are consistent, only heavy
Catalyst is used again）, to carrying out repeating catalytic performance test by halogenation modification and unmodified sulfonate resin, design parameter is such as
Table 1.
The halogenation modification of table 1 and unmodified sulfonate resin repeat to catalyze and synthesize progallin A performance evaluation table
As shown in Table 1, unmodified sulfonate resin is after 5 repetitions catalyze and synthesize progallin A, products collection efficiency
It is decreased obviously with catalyst recovery yield, and halogenation sulfonate resin has preferable Repeatability, by 5 repetition Catalysis experiments
Afterwards, products collection efficiency rate of descent is only 3~13 %, and catalyst recovery yield only declines 4~10 %.On the whole, by being repeated several times
After experiment, halogenation sulfonate resin performance is simultaneously not affected by too big influence.
Claims (2)
1. a kind of synthetic method of gallic acid lower alkyl alcohol ester, it is characterised in that comprise the following steps：
（1）Gallic acid and low-grade alkane alcohol are placed in reactor, add hydrophobically modified azochlorosulfonate acid resin catalyst, is stirred,
65~120 DEG C are warming up to, 4~10 h is reacted, filtering, obtains filtrate；The sulfonic acid of the gallic acid, low-grade alkane alcohol and hydrophobically modified
The mass ratio of resin catalyst is 1:1.0~4.5:0.2~0.5；The sulfonate resin of the hydrophobically modified is that halogenation occurs for phenyl ring
The polystyrene sulfonate resin of gained is reacted, specific method of modifying is：Using the mass ratio of bromine and polystyrene sulfonate resin as 0.6
~1:1, bromine is added in polystyrene sulfonate resin and solvent, stirring, at 50~60 DEG C, lucifuge is reacted to solution decolourization,
Filtering, is cleaned to neutrality with water, obtains the sulfonate resin of hydrophobically modified；The low-grade alkane alcohol is the saturation unitary of carbon number≤6
Alcohol；
（2）By step（1）Excessive alcohol is evaporated off in gained filtrate, obtains crude product, then is recrystallized with deionized water, filters, and dries,
Obtain gallic acid lower alkyl alcohol ester.
2. the synthetic method of gallic acid lower alkyl alcohol ester according to claim 1, it is characterised in that：Step（1）In, it is described
Solvent is water.
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| CN111747848B (en) * | 2020-06-12 | 2023-04-11 | 遵义市倍缘化工有限责任公司 | Method for catalytically synthesizing propyl gallate by using lignin-based catalyst |
| CN114436829A (en) * | 2020-11-02 | 2022-05-06 | 杭州千泰生物科技有限公司 | Preparation method of phenyl salicylate |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3256250A (en) * | 1961-09-26 | 1966-06-14 | Socony Mobil Oil Co Inc | Sulfonated ion exchange resin having an electronegative no2 substituent |
| FR2139877B1 (en) * | 1971-05-28 | 1973-07-13 | Rohm & Haas | |
| US4269943A (en) * | 1979-08-23 | 1981-05-26 | Rohm And Haas Company | Thermally stable resins prepared by bromination or chlorination of aromatic polymer beads followed by sulphonation |
| CN1030321C (en) * | 1992-03-13 | 1995-11-22 | 中国石油化工总公司抚顺石油化工研究院 | Method for preparing high-temp-resistant strong acid type cation exchange resin catalyst |
| CN1167011A (en) * | 1996-05-31 | 1997-12-10 | 浦昭伦 | Method for preparing high thermal stability sulfonic acid type cation exchange resin catalyst |
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