CN106278866A - A kind of 2 alkyl replace .beta.-methylacrylic acid and the synthetic method of ester thereof - Google Patents
A kind of 2 alkyl replace .beta.-methylacrylic acid and the synthetic method of ester thereof Download PDFInfo
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- CN106278866A CN106278866A CN201610578687.6A CN201610578687A CN106278866A CN 106278866 A CN106278866 A CN 106278866A CN 201610578687 A CN201610578687 A CN 201610578687A CN 106278866 A CN106278866 A CN 106278866A
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/347—Preparation of carboxylic acids or their salts, halides or anhydrides by reactions not involving formation of carboxyl groups
- C07C51/363—Preparation of carboxylic acids or their salts, halides or anhydrides by reactions not involving formation of carboxyl 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
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/347—Preparation of carboxylic acids or their salts, halides or anhydrides by reactions not involving formation of carboxyl groups
- C07C51/377—Preparation of carboxylic acids or their salts, halides or anhydrides by reactions not involving formation of carboxyl groups by splitting-off hydrogen or functional groups; by hydrogenolysis of functional groups
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- C—CHEMISTRY; METALLURGY
- 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
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Abstract
The invention provides a kind of 2 alkyl and replace .beta.-methylacrylic acid and the synthetic method of ester thereof, comprise the following steps: with 2 alkyl butanoic acid, the first catalyst and halogen for Material synthesis 2 halo 2 alkyl n-butyric acie；With 2 halo 2 alkyl n-butyric acies, solvent and inorganic base for Material synthesis 2 alkyl crotonic ester；With 2 alkyl crotonic ester, the second catalyst and alcohol for Material synthesis 2 alkyl crotonic ester.The invention has the beneficial effects as follows: provide a kind of 2 alkyl and replace .beta.-methylacrylic acid and the synthetic method of ester thereof, and respectively step reaction solvent for use all recycles, after filtering finished product, aqueous phase recycles, non-wastewater discharge, after hydrogen halides tail gas absorption, obtain coproduct hydrogen hydracid (espespecially hydrobromic acid and hydrochloric acid).
Description
Technical field
The present invention relates to the technical field of fine chemical product, refer more particularly to a kind of 2-position alkyl replace .beta.-methylacrylic acid and
The synthetic method of its ester.
Background technology
.beta.-methylacrylic acid (formula II, has another name called: 3-methacrylic acid) and derivant thereof are important organic intermediates, due in structure
Contain double bond and carboxyl simultaneously, there is excellent reactivity worth, the neck such as medicine, pesticide can be widely used in as intermediate or raw material
The synthesis of territory organic chemistry product.
2-position alkyl replaces .beta.-methylacrylic acid (having another name called: 3-methyl-2-alkyl acrylic) and ester thereof, belongs to the replacement of .beta.-methylacrylic acid 2-position and spreads out
A biological series, can be used for the field such as medicine, pesticide as organic intermediate, can be especially useful for plant growing in pesticide
The preparation of regulator, antibacterial etc..But there is presently no the technique production method preparing this product.
Summary of the invention
The invention aims to overcome the deficiencies in the prior art, it is provided that a kind of 2-position alkyl replace .beta.-methylacrylic acid and
The synthetic method of ester.
The present invention is to be achieved through the following technical solutions:
The invention provides a kind of 2-position alkyl and replace .beta.-methylacrylic acid and the synthetic method of ester thereof, this 2-position alkyl replaces Fructus Crotonis
The synthetic method of acid and ester thereof comprises the following steps:
With 2-alkyl butanoic acid, the first catalyst and halogen for Material synthesis 2-halo-2-alkyl n-butyric acie；Wherein, 2-alkane
The weight ratio of base butanoic acid and the first catalyst is 1:1-5%；The molar basis of 2-alkyl butanoic acid and halogen is than for 1:1.1-1.5
Times；
With 2-halo-2-alkyl n-butyric acie, solvent and inorganic base for Material synthesis 2-alkyl crotonic ester；Wherein, 2-halo-
2-alkyl n-butyric acie with the weight ratio of solvent is: 1:1-3；2-halo-2-alkyl n-butyric acie with the molar basis ratio of inorganic base is
1:1.0-1.5；
With 2-alkyl crotonic ester, the second catalyst and alcohol for Material synthesis 2-alkyl crotonic ester；Wherein, 2-alkyl crotonic
Sour is 1:0.1-2% with described second catalyst weight ratio；Described 2-alkyl crotonic ester with the molar basis ratio of described alcohol is
1:1-5.
Preferably, described first catalyst is Phosphorous chloride., red phosphorus, phosphorus pentachloride.
Preferably, when synthesizing 2-halo-2-alkyl n-butyric acie, temperature is maintained at 25～100 degrees Celsius, and feed time is
1～5 hour, keep 4～1 hours.
Preferably, when synthesizing 2-alkyl crotonic ester, temperature is maintained at 80～100 degrees Celsius, and the retention time is 6～12 little
Time.
Preferably, when synthesizing 2-alkyl crotonic ester, temperature is maintained at 60～130 degrees Celsius, and the retention time is 4～10
Hour.
Preferably, described inorganic base is potassium hydroxide or sodium hydroxide；Described solvent is dehydrated alcohol or methanol.
Preferably, described second catalyst is mineral acid.
Preferably, described second catalyst is sulphuric acid, hydrochloric acid or phosphoric acid.
The invention has the beneficial effects as follows: provide a kind of 2-position alkyl and replace .beta.-methylacrylic acid and the synthetic method of ester thereof, and respectively
Step reaction solvent for use all recycles, and filters aqueous phase after finished product and recycles, non-wastewater discharge, hydrogen halides (espespecially hydrogen bromide,
Hydrogen chloride) after tail gas absorption, obtain coproduct hydrogen hydracid (espespecially hydrobromic acid and hydrochloric acid).
Accompanying drawing explanation
Fig. 1 is the flow chart that the 2-position alkyl that the embodiment of the present invention provides replaces the synthetic method of .beta.-methylacrylic acid and ester thereof；
Fig. 2 be the 2-position alkyl that the embodiment of the present invention provides replace the 2-halo in the synthetic method of .beta.-methylacrylic acid and ester thereof-
2-alkyl n-butyric acie synthesis schematic diagram；
Fig. 3 is the 2-alkyl bar that the 2-position alkyl that the embodiment of the present invention provides replaces in the synthetic method of .beta.-methylacrylic acid and ester thereof
Bean acid synthesis synthesis schematic diagram；
Fig. 4 is the 2-alkyl bar that the 2-position alkyl that the embodiment of the present invention provides replaces in the synthetic method of .beta.-methylacrylic acid and ester thereof
Bean acid esters synthesis synthesis synthesis schematic diagram.
Detailed description of the invention
In order to make the purpose of the present invention, technical scheme and advantage clearer, below in conjunction with drawings and Examples, right
The present invention is further elaborated.Should be appreciated that specific embodiment described herein only in order to explain the present invention, and
It is not used in the restriction present invention.
Referring to Fig. 1, Fig. 1 is the flow process that the 2-position alkyl that the present invention provides replaces the synthetic method of .beta.-methylacrylic acid and ester thereof
Figure.
Embodiments providing a kind of 2-position alkyl and replace .beta.-methylacrylic acid and the synthetic method of ester thereof, this 2-position alkyl takes
Synthetic method for .beta.-methylacrylic acid and ester thereof comprises the following steps:
With 2-alkyl butanoic acid, the first catalyst and halogen for Material synthesis 2-halo-2-alkyl n-butyric acie；Wherein, 2-alkane
The weight ratio of base butanoic acid and the first catalyst is 1:1-5%；The molar basis of 2-alkyl butanoic acid and halogen is than for 1:1.1-1.5
Times；
With 2-halo-2-alkyl n-butyric acie, solvent and inorganic base for Material synthesis 2-alkyl crotonic ester；Wherein, 2-halo-
2-alkyl n-butyric acie with the weight ratio of solvent is: 1:1-3；2-halo-2-alkyl n-butyric acie with the molar basis ratio of inorganic base is
1:1.0-1.5；
With 2-alkyl crotonic ester, the second catalyst and alcohol for Material synthesis 2-alkyl crotonic ester；Wherein, 2-alkyl crotonic
Sour is 1:0.1-2% with described second catalyst weight ratio；Described 2-alkyl crotonic ester with the molar basis ratio of described alcohol is
1:1-5.
It is an object of the invention to provide that a kind of raw material is easy to get, unit is simple to operate, three-waste free discharge, be prone to industrialized production
2-position alkyl replace .beta.-methylacrylic acid and the synthetic method of esters product thereof.
The program may be summarized to be: with 2-position alkyl (carbon number is as 1-4) replacement n-butyric acie, halogen as initial feed, passes through
2-position halo, dehydrohalogenation two step are synthesized 2-position alkyl and replace .beta.-methylacrylic acid, then replace .beta.-methylacrylic acid and carbon with 2-position alkyl
Number is raw material for the low carbon chain fatty alcohol of 1-8, and through esterification process synthesis 2-position, alkyl replaces crotonates series of products.
Being synthesized by three steps when concrete preparation, concrete reaction and operation scheme are as follows:
1,2-halo-2-alkyl n-butyric acie synthesis
Synthetic route such as Fig. 2, wherein, R2 is in carbon number 1-8, low carbon chain；X is halogen, preferably chlorine and bromine；Catalysis
Agent can be Phosphorous chloride., red phosphorus, phosphorus pentachloride, preferably Phosphorous chloride..
Practical operation includes following process conditions:
Reactant ratio, calculates for radix with main material 2-alkyl butanoic acid consumption, including weight basis and molar basis, urges
Agent consumption is the 1-5% (preferably 2-3%) of weight basis；Halogen consumption is 1.1-1.5 times of (preferably 1.1-of molar basis
1.2 times).
Feed way, reaction temperature and response time, halogen feed way liquid uses dropping, gas to use bubbling side
Formula, charging process and complete later holding process, temperature is maintained at 25-100 DEG C (preferably 50-75 DEG C), and feed time 1-5 is little
Time (preferably 2-3 hour), keep 4-10 hour (preferably 6-8 hour).
Concrete steps:
In four mouthfuls of reaction bulbs (stirring, thermometer, reflux condensing tube (connecing tail gas absorption), gas conduit), add quantitative
2-alkyl butanoic acid and catalyst, heat up, and adds halogen, reacts and keep.Naturally cool to room temperature, pour 5 times of 2-alkyl fourths into
In the frozen water of acid weight, stirring 15-30 minute, sucking filtration, filter cake is washed with water at pH4-5,60-80 DEG C vacuum drying, obtains
Target product.
2,2-alkyl crotonic ester synthesis
Synthetic route such as Fig. 3, wherein, R2 is in carbon number 1-8, low carbon chain；X is halogen, preferably chlorine and bromine；Inorganic
Alkali can be potassium hydroxide or sodium hydroxide；Solvent uses dehydrated alcohol or methanol；Acidization uses hydrochloric acid.
Practical operation includes following process conditions:
Reactant ratio, with main material 2-halo-2-alkyl butanoic acid consumption for radix calculate, including weight basis and mole
Radix, solvent load is 1-3 times (preferably 1.5-2 times) of weight basis；Inorganic base consumption is 1.0-1.5 times of molar basis
(preferably 1.1-1.3 times).
Reaction temperature and response time, temperature is maintained at 80-100 DEG C (preferably reflux temperature), and the retention time is that 6-12 is little
Time (preferably 8-10 hour).
Concrete steps:
In four mouthfuls of reaction bulbs, add solvent, 2-halo-2-alkyl butanoic acid, after stirring and dissolving, add inorganic base and the most molten
The solution that agent is made into, is warming up to reaction temperature, keeps.After reaction terminates, cooling down, filter, mother solution decompression steams solvent, residue
Middle addition and isopyknic 10% potassium hydroxide solution of system, continue reaction 2h, be cooled to room temperature, be neutralized to pH6-with concentrated hydrochloric acid
7, brine ice cools down, and product separates out, sucking filtration, is washed to pH4-5, and vacuum drying obtains target product.
3,2-alkyl crotonic ester Lipase absobed
Synthetic route such as Fig. 4, wherein, R1 be carbon number be the low carbon chain of 1-4；R2 is in carbon number 1-8, low carbon chain；Catalysis
Agent mineral acid, can be sulphuric acid, hydrochloric acid, phosphoric acid, preferably sulfuric acid.
Practical operation includes following process conditions:
Reactant ratio, calculates with main material 2-alkyl crotonic ester consumption for radix, including weight basis and molar basis,
Catalyst amount is the 0.1-2% (preferably 0.5-1%) of weight basis；Alcohol consumption is 1-5 times of (preferably 2-3 of molar basis
Times).
Reaction temperature and response time, temperature is maintained at 60-130 DEG C (before and after the boiling point of preferred alcohols 2 degree, maintain the reflux for),
Keep 4-10 hour (preferably 6-8 hour).
Concrete steps:
In four mouthfuls of reaction bulbs, add quantitative alcohol, 2-alkyl crotonic ester, after stirring and dissolving, add catalyst, be warming up to back
Stream, keeps 4-10h, then changes distillation into, steam the alcohol of excess, and residue washs 2-3 time with isopyknic water, and organic facies is with dry
Drying prescription (anhydrous sodium sulfate, anhydrous magnesium sulfate etc., preferably anhydrous magnesium sulfate) is dried overnight, and filters off desiccant, decompression distillation, collects
Corresponding fraction, obtains target product.
Below with 2-Methyl Butyric Acid as initial feed, chlorine is halide reagent, and ethanol is esterifying agent, synthesizes 2-methyl crotonic
As a example by acid and corresponding ethyl ester, further describe the present invention, but the scope of the present invention be not limited to these embodiments:
Embodiment one 2-chloro-2-Methyl Butyric Acid synthesis
In 250ml four-hole bottle (stirring, thermometer, reflux condensing tube, chlorine conduit), add 1mol2-methylbutanoic acid, then
It is carefully added under about 3ml Phosphorous chloride., stirring and is to slowly warm up to 60 DEG C, the most slowly lead to 1.1mol chlorine (Subtraction method), keep
The steady bubbling of gas, about 2h is complete, keeps 6h, obtains light yellow transparent liquid, pour in 200ml frozen water, stir after natural cooling
Mixing 15min, sucking filtration, filter cake is washed with water to pH4-5, is dried to obtain 2-chloro-2-Methyl Butyric Acid about 125g, and yield 65% (is pressed
2-Methyl Butyric Acid calculates).
Embodiment two 2-methylcrotonic acid synthesizes
In 500ml four-hole bottle, add 150ml dehydrated alcohol, the 1mol 2-chloro-2-Methyl Butyric Acid of embodiment one preparation,
After stirring and dissolving, the solution that addition 1.2mol potassium hydroxide and 100ml dehydrated alcohol are made into, it is warming up to backflow, keeps 6h, chlorination
Potassium separates out in a large number, cools down, filters, and mother solution decompression steams etoh solvent, adds 10% potassium hydroxide solution 200ml in residue,
Backflow 2h, cooling, it is neutralized to pH6-7 with concentrated hydrochloric acid, brine ice cools down, and product separates out, and sucking filtration is washed to pH4-5, is dried to obtain
2-methylcrotonic acid about 80g, fusing point 66-68 DEG C, product purity reaches 99%, and outward appearance is clear crystal shape, yield 70%.
Embodiment three 2-Ethyl.alpha.-methylcrotonate synthesizes
In 500ml four-hole bottle, add 200ml dehydrated alcohol, the 2-methylcrotonic acid of 1mol embodiment two preparation, stir molten
Xie Hou, adds 98% industry concentrated sulphuric acid 5ml, is warming up to backflow, keep 6h, then change distillation into, steam the ethanol of excess, residual
Thing is washed 2-3 time, uses 100ml water every time, and anhydrous magnesium sulfate is dried overnight, and filters, decompression distillation, collects 70-75 DEG C
(60mmHg) fraction, i.e. target product, about 80g, yield 60%, density 0.873, refractive index 1.4364, after second distillation, produce
Product purity reaches more than 99%.
By foregoing description it can be seen that present embodiments provide a kind of 2-position alkyl to replace .beta.-methylacrylic acid and the synthesis of ester thereof
Method, and respectively step reaction solvent for use all recycles, after filtering finished product, aqueous phase recycles, non-wastewater discharge, and hydrogen halides is (especially
Refer to hydrogen bromide, hydrogen chloride) after tail gas absorption, obtain coproduct hydrogen hydracid (espespecially hydrobromic acid and hydrochloric acid).
These are only presently preferred embodiments of the present invention, not in order to limit the present invention, all spirit in the present invention and
Any amendment, equivalent and the improvement etc. made within principle, should be included within the scope of the present invention.
Claims (8)
1. a 2-position alkyl replaces .beta.-methylacrylic acid and the synthetic method of ester thereof, it is characterised in that comprise the following steps:
With 2-alkyl butanoic acid, the first catalyst and halogen for Material synthesis 2-halo-2-alkyl n-butyric acie；Wherein, 2-alkyl fourth
Acid is 1:1-5% with the weight ratio of the first catalyst；The molar basis ratio of 2-alkyl butanoic acid and halogen is for 1:1.1-1.5 times；
With 2-halo-2-alkyl n-butyric acie, solvent and inorganic base for Material synthesis 2-alkyl crotonic ester；Wherein, 2-halo-2-alkane
Base n-butyric acie with the weight ratio of solvent is: 1:1-3；2-halo-2-alkyl n-butyric acie is 1 with the molar basis ratio of inorganic base:
1.0-1.5；
With 2-alkyl crotonic ester, the second catalyst and alcohol for Material synthesis 2-alkyl crotonic ester；Wherein, 2-alkyl crotonic ester with
The weight ratio of described second catalyst is 1:0.1-2%；The molar basis of described 2-alkyl crotonic ester and described alcohol is than for 1:1-
5。
2-position the most according to claim 1 alkyl replaces .beta.-methylacrylic acid and the synthetic method of ester thereof, it is characterised in that described the
One catalyst is Phosphorous chloride., red phosphorus, phosphorus pentachloride.
2-position the most according to claim 2 alkyl replaces .beta.-methylacrylic acid and the synthetic method of ester thereof, it is characterised in that in synthesis
During 2-halo-2-alkyl n-butyric acie, temperature is maintained at 25～100 degrees Celsius, and feed time is 1～5 hour, and holding 4～1 is little
Time.
2-position the most according to claim 2 alkyl replaces .beta.-methylacrylic acid and the synthetic method of ester thereof, it is characterised in that in synthesis
During 2-alkyl crotonic ester, temperature is maintained at 80～100 degrees Celsius, and the retention time is 6～12 hours.
2-position the most according to claim 3 alkyl replaces .beta.-methylacrylic acid and the synthetic method of ester thereof, it is characterised in that in synthesis
During 2-alkyl crotonic ester, temperature is maintained at 60～130 degrees Celsius, and the retention time is 4～10 hours.
2-position the most according to claim 5 alkyl replaces .beta.-methylacrylic acid and the synthetic method of ester thereof, it is characterised in that described nothing
Machine alkali is potassium hydroxide or sodium hydroxide；Described solvent is dehydrated alcohol or methanol.
7. the 2-position alkyl as described in any one of claim 1～6 replaces .beta.-methylacrylic acid and the synthetic method of ester thereof, and its feature exists
In, described second catalyst is mineral acid.
2-position the most according to claim 7 alkyl replaces .beta.-methylacrylic acid and the synthetic method of ester thereof, it is characterised in that described the
Two catalyst are sulphuric acid, hydrochloric acid or phosphoric acid.
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| CN201610578687.6A CN106278866A (en) | 2016-07-21 | 2016-07-21 | A kind of 2 alkyl replace .beta.-methylacrylic acid and the synthetic method of ester thereof |
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| CN201610578687.6A CN106278866A (en) | 2016-07-21 | 2016-07-21 | A kind of 2 alkyl replace .beta.-methylacrylic acid and the synthetic method of ester thereof |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114349631A (en) * | 2022-01-14 | 2022-04-15 | 北京富盛嘉华医药科技有限公司 | Preparation method and application of 4-methoxy crotonic acid |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| JPS56104843A (en) * | 1980-01-23 | 1981-08-20 | Ihara Chem Ind Co Ltd | Preparation of unsaturated carboxylic acid |
| CN1070647A (en) * | 1992-09-30 | 1993-04-07 | 孙伟燕 | Preparation has the method for optically active false bufotoxin amidoalcohol |
-
2016
- 2016-07-21 CN CN201610578687.6A patent/CN106278866A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56104843A (en) * | 1980-01-23 | 1981-08-20 | Ihara Chem Ind Co Ltd | Preparation of unsaturated carboxylic acid |
| CN1070647A (en) * | 1992-09-30 | 1993-04-07 | 孙伟燕 | Preparation has the method for optically active false bufotoxin amidoalcohol |
Non-Patent Citations (2)
| Title |
|---|
| ROBERT E.BUCKLES ET AL.: "The preparation of tiglic and angelic acids and esters", 《JOURNAL OF ORGANIC CHEMISTRY》 * |
| 邢其毅等: "《基础有机化学》", 31 May 2009 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114349631A (en) * | 2022-01-14 | 2022-04-15 | 北京富盛嘉华医药科技有限公司 | Preparation method and application of 4-methoxy crotonic acid |
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Application publication date: 20170104 |