CN1227240C - Process for producing 2-alkyl-4-isothiazoline-3-one - Google Patents
Process for producing 2-alkyl-4-isothiazoline-3-one Download PDFInfo
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- CN1227240C CN1227240C CN 01119093 CN01119093A CN1227240C CN 1227240 C CN1227240 C CN 1227240C CN 01119093 CN01119093 CN 01119093 CN 01119093 A CN01119093 A CN 01119093A CN 1227240 C CN1227240 C CN 1227240C
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Abstract
A chloridizing reagent reacts with a compound disclosed in the formula (I) or a compound disclosed in the formula (II) in a solvent to prepare 2-alkyl-4-isothiazoline-3-ketone, wherein hydrogen chloride in the solvent is insoluble or has low dissolvability and R in the formula represents C1-6 alkyl or aralkyl.
Description
Technical field:
The present invention relates to preparation method as the 2-alkyl-4-isothiazolin-3-ones of industrial disinfection agent.
Background technology:
Isothiazoline-3-ketone as the industrial disinfection agent is the mixture of 2-alkyl-4-isothiazolin-3-ones and 5-chloro-2-alkyl-4-isothiazolin-3-ones.Yet,, need the content of 5-chloro-2-alkyl-4-isothiazolin-3-ones wherein low or do not contain the 2-alkyl-4-isothiazolin-3-ones of this compound along with the mutagenicity problem relevant of nearest appearance with 5-chloro-2-alkyl-4-isothiazolin-3-ones.
Have been found that many methods that prepare 2-alkyl-4-isothiazolin-3-ones.For example, resemble at USP3,849,430 and EP 95907 in proposed, in the acetic ester solvent, N-alkyl-3-sulfydryl propionic acid amide is carried out chlorination, obtain the mixture of 2-alkyl-4-isothiazolin-3-ones and 5-chloro-2-alkyl-4-isothiazolin-3-ones.But the preparation method that this place proposes does not provide any means of the content that reduces 5-chloro-2-alkyl-4-isothiazolin-3-ones.
The method that proposes in EP 0 437 354 is only the 5-chloro-2-alkyl-4-isothiazolin-3-ones in the mixture that is present in 2-alkyl-4-isothiazolin-3-ones hydrochloride and 5-chloro-2-alkyl-4-isothiazolin-3-ones hydrochloride to be carried out neutralization reaction and isolate the method for 2-alkyl-4-isothiazolin-3-ones with relative higher degree with anhydrous ammonia.But this preparation method's program is numerous and diverse, and causes the content of 5-chloro-2-alkyl-4-isothiazolin-3-ones of mutagenicity such as preceding.In addition, the quite a large amount of 2-alkyl-4-isothiazolin-3-ones of loss in the operation of attempting to remove 5-chloro-2-alkyl-4-isothiazolin-3-ones.
Also have, EP0678510 proposes a kind of method, i.e. the mixture of heating 2-alkyl-4-isothiazolin-3-ones hydrochloride and 5-chloro-2-alkyl-4-isothiazolin-3-ones hydrochloride in organic solvent.Utilize the difference of 2-alkyl-4-isothiazolin-3-ones hydrochloride and 5-chloro-2-alkyl-4-isothiazolin-3-ones hydrochloride solubleness in organic solvent, the 2-alkyl-4-isothiazolin-3-ones hydrochloride is made with extra care, but, still with the former the same content that has kept the 5-chloro-2-alkyl-4-isothiazolin-3-ones that is enough to cause mutagenicity, and still to lose 2-alkyl-4-isothiazolin-3-ones inevitably.
As mentioned above, all prior aries all are to obtain 2-alkyl-4-isothiazolin-3-ones by being carried out purifying by the mixture that 5-chloro-2-alkyl-4-isothiazolin-3-ones pollutes, rather than preferably prepare needed 2-alkyl-4-isothiazolin-3-ones.
Yet, remove 5-chloro-2-alkyl-4-isothiazolin-3-ones fully by refining process and be still difficulty, and will lose some 2-alkyl-4-isothiazolin-3-ones inevitably.In addition, owing to increased treating process, make preparation process more complicated.Therefore, in order to obtain highly purified 2-alkyl-4-isothiazolin-3-ones in industrial favourable mode, favourable means are as much as possible to suppress the generation of 5-chloro-2-alkyl-4-isothiazolin-3-ones at preparatory phase, and reduce because the loss of the 2-alkyl-4-isothiazolin-3-ones that purge process causes.
Summary of the invention:
Find out by above-mentioned situation, the purpose of this invention is to provide a kind of method, make by industrial simple method, obtain highly purified 2-alkyl-4-isothiazolin-3-ones, and make this product not contain or contain 5-chloro-2-alkyl-4-isothiazolin-3-ones not causing on the enough low level of mutagenicity with favourable output.
By check, the inventor works out a kind of method for preparing 2-alkyl-4-isothiazolin-3-ones, wherein the generation of 5-chloro-2-alkyl-4-isothiazolin-3-ones significantly reduces, its presentation of results a beyond thought fact, the selectivity that promptly generates 2-alkyl-4-isothiazolin-3-ones and 5-chloro-2-alkyl-4-isothiazolin-3-ones changes along with type of solvent used in reaction significantly.Specifically, in the reaction in the solvent for use solubleness of hydrogenchloride and 2-alkyl-4-isothiazolin-3-ones be found with respect to the mutual relationship between the generation ratio of 5-chloro-2-alkyl-4-isothiazolin-3-ones, this causes of the present invention finishing.
According to the present invention, the method for the 2-alkyl-4-isothiazoline 3-ketone of preparation general formula (III) representative,
Wherein R represents C
1-8Alkyl or aralkyl,
It is characterized in that, the compound of following formula (I) representative,
R has the definition of being given in the aforementioned formula (III) in the formula, or the compound of following formula (II) representative,
R has the definition of being given in the aforementioned formula (III) in the formula, with chlorination reagent reaction, used ratio is every mole of formula (I) compound to 2 equivalent chlorination reagents or every mole of formula (II) compound to 3 molar equivalent chlorination reagents in a kind of solvent (hydrogenchloride is insoluble or has low solubleness therein).
Formula (I), (II) and (III) in the R group represent C1-8 alkyl or aralkyl.Industrial preferable methyl or n-octyl.
Aforementioned solvents preferably should be that compound and chlorination reagent are inert to formula (I), (II) with (III).Inertia is meant that this solvent does not react with formula (I), (II), (III) compound or chlorination reagent.
In addition, above-mentioned solvent preferably should be that hydrogenchloride does not dissolve therein or has those of low solubility.Say that more specifically the solubleness of hydrogenchloride preferably should be molfraction 0.04 or still less in the preferred solvent at normal temperatures and pressures, more preferably 0.03 or still less, more more preferably 0.02 or still less.
Aforementioned solvents preferably should be selected from organic solvent, especially halogenated aliphatic hydrocarbon, halogenated aromatic and aliphatic hydrocarbon.This solvent is methylene dichloride, ethylene dichloride, trichloroethane, tetrachloroethane, chloroform, tetracol phenixin, mono chloro benzene, dichlorobenzene, pentane, hexane, hexanaphthene, heptane and octane preferably.
When enforcement is of the present invention, more preferably formula (I) or formula (II) compound is separated with the hydrochloride of the formula (II) of chlorination reagent reaction generation, and wash described salt with solvent (it does not react with this salt, and this salt solubleness therein is low).
Because the present invention of the 2-alkyl-4-isothiazolin-3-ones of preparation formula (III)
(R represents C in the formula
1-8Alkyl or aralkyl) it is characterized in that formula (I) compound
(R has the identical definition in the aforementioned formula (III) in the formula)
Or the compound of formula (II) representative
(R has the identical definition in the aforementioned formula (III) in the formula)
(wherein hydrogenchloride is insoluble at solvent with chlorination reagent, or have low solubleness) in reaction, the ratio of used chlorination reagent is 2 molar equivalent chlorination reagents/every mole formula (I) compound or 3 molar equivalent chlorination reagents/every mole of formula (II) compound, so in fact do not have 5-chloro-2-alkyl-4-isothiazolin-3-ones (a kind of mutagenicity material) to exist, and 2-alkyl-4-isothiazolin-3-ones can highly selective make.
Also have,, with regard to not needing to resemble in the above-mentioned traditional method, repeat purge process, thereby cause a kind of preparation method of very economical, make the production loss in the purification step reduce to minimum simultaneously because can optionally obtain 2-alkyl-4-isothiazolin-3-ones.
Above-mentioned effect can obtain by using a kind of like this solvent, and in this solvent, the solubleness of hydrogenchloride is below 0.04 by the mole umber under normal temperature and pressure conditions.
By using formula (I), (II), (III) compound and chlorination reagent all are the inert solvent, can reduce the generation of by product effectively.
In addition, by removing by the formula (I) or (II) hydrochloride of formula (III) compound that generates of compound and chlorination reagent reaction, and (this hydrochloride has low solubleness therein with a kind of solvent in increase then, and it does not react with this hydrochloride) process of washing this hydrochloride, just can prepare highly purified 2-alkyl-4-isothiazolin-3-ones.
Explain embodiment preferred in detail.Specifically, the method for the 2-alkyl-4-isothiazolin-3-ones shown in the preparation general formula (III),
(R represents C in the formula
1-8Alkyl or aralkyl),
It is characterized in that the compound shown in the formula (I)
(R has identical definition in the above-mentioned formula (III) in the formula), or the compound shown in the formula (II)
(in the formula R have with above-mentioned formula (III) in identical definition), with chlorination reagent reaction, hydrogenchloride is insoluble in this solvent, perhaps has low solubleness in a kind of solvent.
For the formula used among the present invention (I) or (II) synthetic method of compound of expression, be not specifically limited here.For example, formula (I) and formula (II) compound can by corresponding alkyl ester by with alkyl or aralkylamine at inert organic solvents or do not use and carry out amidate action under the situation of any solvent and easily make.Compound can be made with extra care by recrystallization or distillation shown in formula (I) or the formula (II), is used for this reaction then, and is perhaps minimum if the residual quantity of amine reduces to, and then thick product suitably can be used for this reaction.
Have no particular limits for the chlorination reagent that uses in this reaction.For example, can use chlorine, SULPHURYL CHLORIDE etc., but industrially wish most to use chlorine.If owing to use excessive chlorination reagent then be easy to generate 5-chloro-2-alkyl-4-isothiazolin-3-ones, so should be only use chlorination reagent according to the ratio of 2 molar equivalent chlorination reagents/every mole formula (I) compound and 3 molar equivalent chlorination reagents/every mole of formula (II) compound.Particularly, as shown in formula (IV) and formula V below, when use formula (I) compound, should use 1.8 to 2.5 moles, preferred 1.9 to 2.2 moles, more preferably 2.0 to 2.1 moles (chlorination reagent), and when use formula (II) compound, should use 2.8 to 3.5 moles, preferred 2.9 to 3.2 moles, more preferably 3.0 to 3.1 moles (chlorination reagent).
Formula (IV)
Formula V
The used solvent of the present invention should be such: hydrogenchloride is insoluble therein, perhaps has low solubleness.The solubleness of hydrogenchloride preferably should be below 0.04 by the mole umber.Molar part numerical value is less, and to be illustrated in the solvent solubleness of hydrogenchloride lower.The generation of 5-chloro-2-alkyl-4-isothiazolin-3-ones can be suppressed by low umber value.The solvent of wishing usefulness comprises halogenated aliphatic hydrocarbon, halogenated aromatic and fat hydrocarbon.Example comprises methylene dichloride (0.013 (1atm, 298.15K, down with)), ethylene dichloride (0.038), trichloroethane (0.031), tetrachloroethane (0.025), chloroform (0.022), tetracol phenixin (0.013), mono chloro benzene (0.0312), dichlorobenzene (0.022), pentane (0.005), hexanaphthene (0.015), hexane (0.011), heptane (0.015) and octane (0.016).Methylene dichloride, ethylene dichloride, trichloroethane, tetrachloroethane, chloroform, tetracol phenixin and mono chloro benzene should be preferred.In addition, comprise by the mixed solvent that is selected from two or more above-mentioned one group solvent compositions and also can use.
Consumption for solvent is not specifically limited, but wishes it is formula (I) or (II) 2 to 10 times of compound amount, and preferred 3 to 5 times.Reaction can be carried out being lower than under any temperature of solvent for use boiling point.As shown in above-mentioned formula (IV) and the formula V, produce hydrogen chloride gas in the reaction process.The hydrogen chloride gas of some generations and isothiazoline-3-ketone forms hydrochloride, and some are dissolved in the solvent, and some discharge from reaction system.When needing, the hydrogenchloride in the solvent can be by heating, with nitrogen replacement or place the inferior method of vacuum condition to remove.
As mentioned above, the generation of 5-chloro-2-alkyl-4-isothiazolin-3-ones can be suppressed by the present invention, and 2-alkyl-4-isothiazolin-3-ones can optionally obtain, but a small amount of 5-chloro-2-alkyl-4-isothiazolin-3-ones that is present in the reaction mixture should be removed by the 2-alkyl-4-isothiazolin-3-ones hydrochloride that generates in the filtering reaction, this hydrochloride is with any solvent (this salt has low solubility therein, and this salt and its do not react) washing then.Even increased this purification step, the loss of 2-alkyl-4-isothiazolin-3-ones also is very a spot of.
Be scattered in the water, neutralize, can change it into 2-alkyl-4-isothiazolin-3-ones by hydrochloride with inert organic solvents extraction and removal solvent with alkali with 2-alkyl-4-isothiazolin-3-ones.Kind for used alkali in neutralization procedure is not specifically limited.Wherein, from easy processing and economic aspect, preferred mineral alkali, for example yellow soda ash.It is not specifically limited for temperature used in the neutralizing effect, but preferably is lower than 50 ℃, because can reduce the color of product.
The 2-alkyl-4-isothiazolin-3-ones that in this way obtains is substantially devoid of 5-chloro-2-alkyl-4-isothiazolin-3-ones, and perhaps content is lower than 0.5%, and product is the very pure product that does not cause mutagenicity.
Embodiment:
Embodiment 1
With 120g (0.508mol) N, N '-dimethyl-3,3 '-dithio propionic acid amide and 480ml methylene dichloride pack into and have agitator, chlorine ingress pipe, thermometer and be furnished with in 2 liters of four-hole boiling flasks of condenser of calcium chloride distiller.During 3 hours 15 minutes 108g (1.523mol) chlorine is incorporated in the solution under 39-41 ℃ of temperature, at room temperature stirred liquid then.Decompress filter goes out sedimentary crystal, uses washed with dichloromethane.With crystalline dispersion in 400ml water, and with the yellow soda ash pH7 that neutralizes.Use dichloromethane extraction solution, remove and desolvate, obtain 90.12g (77% yield) 2-methyl-4-isothiazoline-3-ketone light brown solid.
Embodiment 2
The same terms by embodiment 1 reacts, but the use hexanaphthene (molfraction 0.015,1atm, 298, as shown in table 1 15k) as solvent, obtain 2-methyl-4-isothiazoline-3-ketone, productive rate 70%.
Embodiment 3
The same terms by embodiment 1 reacts, but uses chloroform as reaction solvent and be used for the washing salt hydrochlorate, obtains 2-methyl-4-isothiazoline-3-ketone, productive rate 75%.
Embodiment 4
The same terms by embodiment 1 reacts, but uses N, N '-di-n-octyl-3,3 '-dithio propionic acid amide is as raw material, and with methylene dichloride as reaction solvent, with mono chloro benzene washing salt hydrochlorate, obtain 2-n-octyl-4-isothiazoline-3-ketone, productive rate 71%.
Embodiment 5
React by embodiment 4 the same terms, but use mono chloro benzene, obtain 2-n-octyl-4-isothiazoline-3-ketone, productive rate 71% as reaction solvent.
Embodiment 6
React by embodiment 4 the same terms, but the mixture that uses mono chloro benzene and dichlorobenzene obtains 2-n-octyl-4-isothiazoline-3-ketone, productive rate 70% as reaction solvent.
Embodiment 7
React by embodiment 1 the same terms, but use N, N '-dibenzyl-3,3 '-dithio propionic acid amide with the solvent of mono chloro benzene as reaction solvent and washing salt hydrochlorate, obtain 2-benzyl-4-isothiazoline-3-ketone, productive rate 70% as raw material.
Comparative examples
React by embodiment 1 the same terms, but use ethyl acetate, obtain 2-methyl-4-isothiazoline-3-ketone, productive rate 51% as solvent.
[table 1]
The solvent wash hydrochloride solvent that uses in the R reaction
Embodiment 1 methyl dichloro methane methylene dichloride
(0.013)
Embodiment 2 methylcyclohexane methylene dichloride
(0.015)
Embodiment 3 trichloroethane chloroforms
(0.022)
Embodiment 4 n-octyl methylene dichloride mono chloro benzenes
(0.013)
Embodiment 5 n-octyl mono chloro benzene mono chloro benzenes
(0.0312)
Embodiment 6 n-octyl mono chloro benzenes and methylene dichloride mono chloro benzene
Mixed solvent (0.025)
Embodiment 7 benzyl mono chloro benzene mono chloro benzenes
(0.0312)
Methyl acetic acid ethyl ester ethyl acetate is implemented in contrast
Example (0.240)
Numeral in the table in " solvent that uses in the reaction " hurdle internal bracket is the molfraction of hydrogenchloride solubleness at normal temperatures and pressures.The crystalline purity that obtains in embodiment 1 to 7 and comparative examples is by high-efficient liquid phase chromatogram technique analysis, and carries out mutagenicity (Ames) test.Table 2 is listed this result."+" expression has clear and definite ill effect to matrix, and "-" expression does not have ill effect.
[table 2]
The different Ames test of the different thiophene 5-of 2-alkyl-4-chloro-2-alkyl-4-
Azoles quinoline-3-ketone (%) thiazoline-3-ketone (%)
Embodiment 1>99.9<0.1-
Embodiment 2>99.5<0.5-
Embodiment 3>99.0<1.0-
Embodiment 4>99.9<0.1-
Embodiment 5>99.9<0.1-
Embodiment 6>99.9<0.1-
Embodiment 7>99.9<0.1-
Comparative examples 47 53+
As noted in Table 2, the method preparation for preparing 2-alkyl-4-isothiazolin-3-ones according to the present invention has highly selective very and does not in fact contain the 2-alkyl-4-isothiazolin-3-ones of mutagenicity material 5-chloro-2-alkyl-4-isothiazolin-3-ones.In addition, the Ames test result is at all
All be negative among the embodiment.
In an embodiment, the hydrochloride of 2-alkyl-4-isothiazolin-3-ones filters, and uses solvent wash, but because reaction is carried out with highly selective, the washing salt hydrochlorate can not obtain having the 2-alkyl-4-isothiazolin-3-ones of enough purity yet.
In addition, all the elements of JPA No.11 (1999)-369205 are introduced this explanation as a reference.
Claims (7)
1. method for preparing the 2-alkyl-4-isothiazolin-3-ones shown in the general formula (III),
(III)
R represents C in the formula
1-8Alkyl or aralkyl,
It is characterized in that compound shown in the formula (I)
(I)
R has identical definition in the aforementioned formula (III) in the formula,
Or compound shown in the formula (II)
R has identical definition in the aforementioned formula (III) in the formula, and with the chlorination reagent reaction, wherein said solvent is an inert to compound and the chlorination reagent of formula (I), (II), (III) in solvent; Hydrogenchloride is undissolved or has low solubleness in above-mentioned solvent, less than 0.04, used ratio is 2 moles of chlorination reagents/every mole of formula (I) compound or 3 moles of chlorination reagent/every mole of formula (II) compounds to the solubleness of hydrogenchloride in described solvent in molfraction at normal temperatures and pressures.
2. the described method for preparing 2-alkyl-4-isothiazolin-3-ones of claim 1, wherein said solvent is an organic solvent.
3. the described method for preparing 2-alkyl-4-isothiazolin-3-ones of claim 2, wherein said organic solvent is selected from halogenated aliphatic hydrocarbon, halogenated aromatic, and aliphatic hydrocarbon.
4. the described method for preparing 2-alkyl-4-isothiazolin-3-ones of claim 3, wherein said solvent are selected from following at least a: methylene dichloride, ethylene dichloride, trichloroethane, tetrachloroethane, chloroform, tetracol phenixin, mono chloro benzene, dichlorobenzene, pentane, hexane, hexanaphthene, heptane, octane.
5. the described method for preparing 2-alkyl-4-isothiazolin-3-ones of one of claim 1 to 4, wherein said R represents methyl.
6. the described method for preparing 2-alkyl-4-isothiazolin-3-ones of one of claim 1 to 4, wherein said R is a n-octyl.
7. the described method for preparing 2-alkyl-4-isothiazolin-3-ones of claim 1 is comprising filtering by the hydrochloride of formula (I) or formula (II) compound and formula (III) compound of chlorination reagent reaction generation and with inert and hydrochloride is had the solvent wash hydrochloride of low solubility.
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JP4889737B2 (en) * | 2006-04-03 | 2012-03-07 | 北京天▲きん▼化工有限責任公司 | Production of N-substituted isothiazolinone derivatives |
WO2012031407A1 (en) * | 2010-09-10 | 2012-03-15 | 大连星原化学有限公司 | Preparation method of isothiazolinone and derivatives thereof in gas carrier |
CN102786491B (en) * | 2011-05-19 | 2014-06-11 | 大连百傲化学股份有限公司 | Preparation method of 2-methyl-4-isothiazolin-3-one |
CN104961705B (en) * | 2015-07-02 | 2017-05-24 | 大连百傲化学股份有限公司 | Process for synthesizing 4,5-dichloro-2-methylisothiazolinone by one-pot method |
CN106699680B (en) * | 2017-01-16 | 2021-05-18 | 甘肃开美高精细化工有限公司 | Preparation method of high-purity 2-alkyl-4-isothiazoline-3-ketone |
CN112110870B (en) * | 2020-09-28 | 2022-06-03 | 大连百傲化学股份有限公司 | Preparation method of 2-methyl-4-isothiazoline-3-ketone aqueous solution |
CN113651769B (en) * | 2021-08-31 | 2023-07-28 | 陕西中杰科仪化学科技有限公司 | Continuous production method of 2-methyl-4-isothiazolin-3-ketone |
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