CN109232295A - A kind of method for crystallising of 1,1- cyclohexanediacetic acid monoamides - Google Patents
A kind of method for crystallising of 1,1- cyclohexanediacetic acid monoamides Download PDFInfo
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- CN109232295A CN109232295A CN201811245437.6A CN201811245437A CN109232295A CN 109232295 A CN109232295 A CN 109232295A CN 201811245437 A CN201811245437 A CN 201811245437A CN 109232295 A CN109232295 A CN 109232295A
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- cyclohexanediacetic acid
- cyclohexanediacetic
- crystallising
- monoamides
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C231/00—Preparation of carboxylic acid amides
- C07C231/02—Preparation of carboxylic acid amides from carboxylic acids or from esters, anhydrides, or halides thereof by reaction with ammonia or amines
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C231/00—Preparation of carboxylic acid amides
- C07C231/12—Preparation of carboxylic acid amides by reactions not involving the formation of carboxamide groups
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C231/00—Preparation of carboxylic acid amides
- C07C231/22—Separation; Purification; Stabilisation; Use of additives
- C07C231/24—Separation; Purification
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C2601/00—Systems containing only non-condensed rings
- C07C2601/12—Systems containing only non-condensed rings with a six-membered ring
- C07C2601/14—The ring being saturated
Abstract
The present invention provides the method for crystallising of one kind 1,1- cyclohexanediacetic acid monoamides, comprising the following steps: under conditions of 50~70 DEG C of stirrings, H is added dropwise into the ammonium salt solution of 1,1- cyclohexanediacetic acid monoamides2SO4It is 0.5%~2% to material acidity, it is 10-20r/min that mixing speed is adjusted after precipitating crystal during being added dropwise, and after sulfuric acid is added dropwise, 2~2.5h is kept the temperature under conditions of 45~55r/min, is centrifuged, is washed, it is dry, obtain 1,1- cyclohexanediacetic acid monoamides.Provided by the invention 1, the method for crystallising of 1- cyclohexanediacetic acid monoamides, pass through the technological parameter in optimization crystallization process, so that the 1 of preparation, 1- cyclohexanediacetic acid monoamides product yield is the purity that can reach 99.9% or more up to 98% or more, and without recrystallizing and refining, simplifies production technology, production efficiency is improved, large-scale industrial production is suitble to.
Description
Technical field
The present invention relates to chemical production technical fields, more particularly to the crystallization side of one kind 1,1- cyclohexanediacetic acid monoamides
Method.
Background technique
1,1- cyclohexanediacetic acid monoamides is the important medicine intermediate for synthesizing antiepileptic Gabapentin.It closes at present
Method at 1,1- cyclohexanediacetic acid monoamides is that 1,1- cyclohexanediacetic acid acid anhydride and high concentration ammonium hydroxide are anti-at relatively high temperatures
It answers, acquired solution acidification, crystallization is then centrifuged for, and is dried, is obtained 1,1- cyclohexanediacetic acid monoamides, synthetic route is as follows.
The generally existing yield of crystallization processes at present during existing synthesis 1,1- cyclohexanediacetic acid monoamides is low, with
And need to recrystallize and can be only achieved higher purity, it is relatively low so as to cause 1,1- cyclohexanediacetic acid monoamides production efficiency
The disadvantages of.Therefore, a kind of simple process, product yield and higher 1, the 1- hexamethylene for being suitable for industrialized production of purity are found
The method for crystallising of base oxalic acid monoamides is most important.
Summary of the invention
It is lower there are yield for the existing crystallization processes prepared during 1,1- cyclohexanediacetic acid monoamides and need
The problem of can be only achieved higher degree is recrystallized, the present invention provides the preparation side of one kind 1,1- cyclohexanediacetic acid monoamides
Method.
In order to solve the above technical problems, present invention provide the technical scheme that
The method for crystallising of one kind 1,1- cyclohexanediacetic acid monoamides, comprising the following steps:
Under conditions of 50~70 DEG C of stirrings, H is added dropwise into the ammonium salt solution of 1,1- cyclohexanediacetic acid monoamides2SO4Extremely
Material acidity is 0.5%~2%, and it is 10-20r/min that mixing speed is adjusted after precipitating crystal during being added dropwise, and sulfuric acid knot is added dropwise
Shu Hou keeps the temperature 2~2.5h under conditions of 45~55r/min, is centrifuged, and washs, dry, obtains 1,1- cyclohexanediacetic acid list acyl
Amine.
Compared with the existing technology, the method for crystallising of 1,1- cyclohexanediacetic acid monoamides provided by the invention, higher
At a temperature of crystallization, avoid (NH4)2SO4Precipitation, reduce the content of impurity in 1,1- cyclohexanediacetic acid monoamides；Heat preservation
Time is long and selects lower mixing speed after precipitating crystal, and gives crystal sufficient ageing time, so that 1,1- cyclohexyl two
Acetic acid monoamides crystal is big and uniform, tunes up mixing speed in later period insulating process, has cleaned crystal form surface, and product impurity is few,
Content is high, and not needing recrystallization can reach higher purity；By the way of sulfuric acid is slowly added dropwise, avoid since sulfuric acid adds
Entering heat release causes temperature to increase, and have to using brine ice cooling the problem of, simplify technique, reduce energy consumption.The present invention
The method for crystallising of 1, the 1- cyclohexanediacetic acid monoamides provided, by the technological parameter in optimization crystallization process, so that preparation
1,1- cyclohexanediacetic acid monoamides product yield can reach 99.9% or more up to 98% or more, and without recrystallizing and refining
Purity, simplify production technology, improve production efficiency, be suitble to large-scale industrial production.
Preferably, the mass concentration of the sulfuric acid is 40~60%, and the time that sulfuric acid is added dropwise is 5.5~6.5h.
Preferred sulfuric acid concentration can reduce the reaction heat released in acidization, drop without using brine ice to reaction
Temperature reduces energy consumption, simplifies technique；Preferred time for adding can be such that acidification reaction carries out more abundant, improve the receipts of product
Rate.
Preferably, when sulfuric acid being added dropwise before precipitating crystal, mixing speed is 75~85r/min.
The ammonium salt solution and sulfuric acid that preferred mixing speed can make 1,1- cyclohexanediacetic acid monoamides are when shorter
It is interior to be uniformly mixed, improve reaction speed.
Preferably, the preparation method of the ammonium salt solution of 1, the 1- cyclohexanediacetic acid monoamides includes the following steps:
Under conditions of 25~35 DEG C, 1,1- cyclohexanediacetic acid acid anhydride liquid is added dropwise in ammonium hydroxide, keeps the temperature 1~1.5h, active carbon is added
Decoloration, keeps the temperature 0.5~1h, and filtering obtains the ammonium salt solution of 1,1- cyclohexanediacetic acid monoamides.
By controlling aminating reaction temperature at 25~35 DEG C, 1,1- cyclohexanediacetic acid can be avoided to hydrolyze as far as possible, reduced
Active carbon decoloring is added in the generation of by-product after ammonification, product content can be made high and white color, optimize the matter of final products
Amount；The preferred insulation reaction time can be such that reaction carries out more abundant, improve the conversion ratio of 1,1- cyclohexanediacetic acid acid anhydride, from
And improve the yield of final products.
Preferably, the molar ratio of 1, the 1- cyclohexanediacetic acid acid anhydride and the ammonium hydroxide is 1:1.2~1.5.
The utilization rate of 1,1- cyclohexanediacetic acid acid anhydride can be improved in preferred material rate, to improve 1,1- cyclohexyl
The yield of oxalic acid monoamides product.
Preferably, the mass percentage content of ammonia is 8~15% in the ammonium hydroxide.
Preferred ammonia concn, after the ammonium salt solution of 1,1- cyclohexanediacetic acid monoamides can be made to be acidified, impurity inorganic salts
It is not easy to be precipitated.
Preferably, the time for adding of 1, the 1- cyclohexanediacetic acid acid anhydride liquid is 2~3h.
It is more abundant that the time for adding of preferred 1,1- cyclohexanediacetic acid acid anhydride liquid can be such that reaction carries out, and avoids by-product
Generation, reduce by 1,1- cyclohexanediacetic acid monoamides ammonium salt solution in impurity content.
Preferably, the additional amount of the active carbon is 1, the 1- cyclohexanediacetic acid acid anhydride liquid and the ammonium hydroxide total weight
1~2%.
The additional amount of preferred active carbon can make under conditions of activated carbon dosage few as far as possible, as much as possible to remove 1,
Impurity in the ammonium salt solution of 1- cyclohexanediacetic acid monoamides, and make final products white color, the quality of product is improved,
Be conducive to subsequent filter, reduce filtration time, improves production efficiency.
Specific embodiment
In order to make the objectives, technical solutions, and advantages of the present invention clearer, with reference to embodiments, to the present invention
It is further elaborated.It should be appreciated that the specific embodiments described herein are merely illustrative of the present invention, it is not used to
Limit the present invention.
Embodiment 1
A kind of method for crystallising of 1,1- cyclohexanediacetic acid monoamides:
(1) under conditions of 25 DEG C, 1,1- cyclohexanediacetic acid acid anhydride is warming up to 70 DEG C of meltings, is added drop-wise to 8% ammonium hydroxide
In, time for adding 2.5h, the molar ratio of 1,1- cyclohexanediacetic acid acid anhydride and ammonium hydroxide is 1:1.5, keeps the temperature 1.5h, adds 1,1-
The active carbon decoloring of cyclohexanediacetic acid acid anhydride liquid and ammonium hydroxide total weight 2% filters after keeping the temperature 0.5h；
It (2) is 50 DEG C in temperature, under conditions of mixing speed is 85r/min, mass concentration, which is added dropwise, into above-mentioned filtrate is
50% H2SO4It is 0.52% to acidity, mixing speed is adjusted to 20r/min, sulphur after precipitating crystal by time for adding 6.5h
It is 50r/min that mixing speed is adjusted after sour completion of dropwise addition, keeps the temperature 2h, then with centrifuge with the speed centrifugation of 500r/min, water
It washes, is dried in 60-120 DEG C, gained 1,1- cyclohexanediacetic acid monoamides, yield 98.7%, content 99.916%.
Embodiment 2
A kind of method for crystallising of 1,1- cyclohexanediacetic acid monoamides:
(3) under conditions of 35 DEG C, 1,1- cyclohexanediacetic acid acid anhydride is warming up to 70 DEG C of meltings, is added drop-wise to 12% ammonium hydroxide
In, time for adding 2h, the molar ratio of 1,1- cyclohexanediacetic acid acid anhydride and ammonium hydroxide is 1:1.2, keeps the temperature 1.5h, adds 1,1- ring
The active carbon decoloring of hexyl diethyl acid anhydrides liquid and ammonium hydroxide total weight 1% filters after keeping the temperature 1h；
It (4) is 60 DEG C in temperature, under conditions of mixing speed is 75r/min, mass concentration, which is added dropwise, into above-mentioned filtrate is
40% H2SO4It is 1.92% to acidity, mixing speed is adjusted to 10r/min, sulfuric acid after precipitating crystal by time for adding 6h
It is 55r/min that mixing speed is adjusted after completion of dropwise addition, keeps the temperature 2.5h, then with centrifuge with the speed centrifugation of 500r/min, water
It washes, is dried in 60-120 DEG C, gained 1,1- cyclohexanediacetic acid monoamides, yield 98.7%, content 99.941%.
Embodiment 3
A kind of method for crystallising of 1,1- cyclohexanediacetic acid monoamides:
(5) under conditions of 30 DEG C, 1,1- cyclohexanediacetic acid acid anhydride is warming up to 70 DEG C of meltings, is added drop-wise to 15% ammonium hydroxide
In, time for adding 3h, the molar ratio of 1,1- cyclohexanediacetic acid acid anhydride and ammonium hydroxide is 1:1.4, keeps the temperature 1h, adds 1,1- hexamethylene
The active carbon decoloring of base diethyl acid anhydrides liquid and ammonium hydroxide total weight 1.5% filters after keeping the temperature 0.5h；
It (6) is 70 DEG C in temperature, under conditions of mixing speed is 80r/min, mass concentration, which is added dropwise, into above-mentioned filtrate is
60% H2SO4It is 1.26% to acidity, mixing speed is adjusted to 15r/min, sulphur after precipitating crystal by time for adding 5.5h
It is 45r/min that mixing speed is adjusted after sour completion of dropwise addition, keeps the temperature 2h, then with centrifuge with the speed centrifugation of 500r/min, water
It washes, is dried in 60-120 DEG C, gained 1,1- cyclohexanediacetic acid monoamides, yield 98.7%, content 99.937%.
Comparative example 1
A kind of method for crystallising of 1,1- cyclohexanediacetic acid monoamides:
(7) under conditions of 25 DEG C, 1,1- cyclohexanediacetic acid acid anhydride is warming up to 70 DEG C of meltings, is added drop-wise to 8% ammonium hydroxide
In, time for adding 2.5h, the molar ratio of 1,1- cyclohexanediacetic acid acid anhydride and ammonium hydroxide is 1:1.5, keeps the temperature 1h, adds 1,1- ring
The active carbon decoloring of hexyl diethyl acid anhydrides liquid and ammonium hydroxide total weight 2% filters after keeping the temperature 1h；
It (8) is 40 DEG C in temperature, under conditions of mixing speed is 80r/min, mass concentration, which is added dropwise, into above-mentioned filtrate is
55% H2SO4It is 0.92% to acidity, mixing speed is adjusted to 15r/min, sulfuric acid after precipitating crystal by time for adding 6h
It is 50r/min that mixing speed is adjusted after completion of dropwise addition, keeps the temperature 2h, is then centrifuged with centrifuge with the speed of 500r/min, washing,
It is dried in 60-120 DEG C, gained 1,1- cyclohexanediacetic acid monoamides, yield 96.8%, content 98.732%.
Comparative example 2
A kind of method for crystallising of 1,1- cyclohexanediacetic acid monoamides:
(9) under conditions of 25 DEG C, 1,1- cyclohexanediacetic acid acid anhydride is warming up to 70 DEG C of meltings, is added drop-wise to 10% ammonium hydroxide
In, time for adding 2h, the molar ratio of 1,1- cyclohexanediacetic acid acid anhydride and ammonium hydroxide is 1:1.5, keeps the temperature 1h, adds 1,1- hexamethylene
The active carbon decoloring of base diethyl acid anhydrides liquid and ammonium hydroxide total weight 2% filters after keeping the temperature 1h；
It (10) is 25 DEG C in temperature, under conditions of mixing speed is 80r/min, mass concentration, which is added dropwise, into above-mentioned filtrate is
50% H2SO4It is 1.68%, time for adding 6h to acidity, being kept stirring speed is 80r/min, 2h is kept the temperature, then with centrifugation
Machine is dried, gained 1,1- cyclohexanediacetic acid monoamides, yield is with speed centrifugation, the washing of 500r/min in 60-120 DEG C
96.2%, content 97.458%.
Comparative example 3
A kind of method for crystallising of 1,1- cyclohexanediacetic acid monoamides:
(11) under conditions of 25 DEG C, 1,1- cyclohexanediacetic acid acid anhydride is warming up to 70 DEG C of meltings, is added drop-wise to 14% ammonia
In water, time for adding 2.5h, the molar ratio of 1,1- cyclohexanediacetic acid acid anhydride and ammonium hydroxide is 1:1.5, keeps the temperature 1h, adds 1,1-
The active carbon decoloring of cyclohexanediacetic acid acid anhydride liquid and ammonium hydroxide total weight 1% filters after keeping the temperature 1h；
It (12) is 70 DEG C in temperature, under conditions of mixing speed is 80r/min, mass concentration, which is added dropwise, into above-mentioned filtrate is
60% H2SO4It is 1.26%, time for adding 6h to acidity, being kept stirring speed is 80r/min, 2h is kept the temperature, then with centrifugation
Machine is dried, gained 1,1- cyclohexanediacetic acid monoamides, yield is with speed centrifugation, the washing of 500r/min in 60-120 DEG C
97.1%, content 98.459%.
In conclusion the method for crystallising of 1,1- cyclohexanediacetic acid monoamides provided by the invention, simple process do not need
Special equipment, low energy consumption, and side reaction is few, the purity of 1,1- cyclohexanediacetic acid anhydride product obtained can reach 99.9% with
On, yield can reach 98% or more, have broad application prospects.
The foregoing is merely illustrative of the preferred embodiments of the present invention, is not intended to limit the invention, all in essence of the invention
Made any modification, equivalent replacement or improvement etc., should all be included in the protection scope of the present invention within mind and principle.
Claims (8)
1. one kind 1, the method for crystallising of 1- cyclohexanediacetic acid monoamides, which comprises the following steps:
Under conditions of 50~70 DEG C of stirrings, H is added dropwise into the ammonium salt solution of 1,1- cyclohexanediacetic acid monoamides2SO4To material
Acidity is 0.5%~2%, and it is 10-20r/min that mixing speed is adjusted after precipitating crystal during being added dropwise, after sulfuric acid is added dropwise,
2~2.5h is kept the temperature under conditions of 45~55r/min, is centrifuged, and is washed, it is dry, obtain 1,1- cyclohexanediacetic acid monoamides.
2. the method for crystallising of 1,1- cyclohexanediacetic acid monoamides as described in claim 1, which is characterized in that the sulfuric acid
Mass concentration is 40~60%, and the time that sulfuric acid is added dropwise is 5.5~6.5h.
3. the method for crystallising of 1,1- cyclohexanediacetic acid monoamides as described in claim 1, which is characterized in that before precipitating crystal
When sulfuric acid is added dropwise, mixing speed is 75~85r/min.
4. the method for crystallising of 1,1- cyclohexanediacetic acid monoamides as described in claim 1, which is characterized in that 1, the 1- ring
The preparation method of the ammonium salt solution of hexyl oxalic acid monoamides includes the following steps: under conditions of 25~35 DEG C, by 1,1- ring
Hexyl diethyl acid anhydrides liquid is added dropwise in ammonium hydroxide, keeps the temperature 1~1.5h, and active carbon decoloring is added, and keeps the temperature 0.5~1h, and filtering obtains 1,
The ammonium salt solution of 1- cyclohexanediacetic acid monoamides.
5. the method for crystallising of 1,1- cyclohexanediacetic acid monoamides as claimed in claim 4, which is characterized in that 1, the 1- ring
The molar ratio of hexyl diethyl acid anhydrides and the ammonium hydroxide is 1:1.2~1.5.
6. the method for crystallising of 1,1- cyclohexanediacetic acid monoamides as claimed in claim 4, which is characterized in that in the ammonium hydroxide
The mass percentage content of ammonia is 8~15%.
7. the method for crystallising of 1,1- cyclohexanediacetic acid monoamides as claimed in claim 4, which is characterized in that 1, the 1- ring
The time for adding of hexyl diethyl acid anhydrides liquid is 2~3h.
8. the method for crystallising of 1,1- cyclohexanediacetic acid monoamides as claimed in claim 4, which is characterized in that the active carbon
Additional amount be the 1~2% of the 1,1- cyclohexanediacetic acid acid anhydride liquid and the ammonium hydroxide total weight.
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