JP2002003462A - Method for producing lysine ester triisocyanate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a simple method for producing a lysine ester triisocyanate free from discoloration. SOLUTION: This method for producing a lysine ester triisocyanate of general formula (II) (R is an alkylene) by reacting a triamine of general formula (I) or its salt with phosgene, comprises a process for bringing a mixture containing the lysine ester triisocyanate represented by general formula (II) obtained by reacting the triamine represented by general formula (I) or its salt with phosgene into contact with activated carbon or a metal halide and distilling the mixture.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a method for producing lysine ester triisocyanate useful as a raw material for polyurethane and the like, a coating agent for resins, and the like.

[0002]

2. Description of the Related Art Aliphatic isocyanates are reacted with a corresponding amine or a salt thereof with phosgene, and the resulting crude isocyanate is subjected to rectification to produce a product, which may be colored yellow or the like. . This coloring is a major problem when aliphatic isocyanates are used in applications such as paints.

[0003] Conventionally, as a method for producing a non-colored lysine ester triisocyanate, Japanese Patent Publication No.
The method disclosed in Japanese Patent Publication No. 3 (JP-A) No. 3 is known. This publication discloses that after lysine monoalkyl ester trihydrochloride is suspended and dispersed in a water-immiscible organic solvent before the reaction with phosgene, the resultant is separated by filtration and the filter cake is washed, and the water-immiscible organic solvent is re-exposed. A pretreatment of dispersion in lysine was carried out to give lysine monoalkyl ester trihydrochloride substantially free of water, and then this was reacted with phosgene in the presence of an inert organic solvent to remove the resulting reaction solution. After removing the solvent and tar, 10
Disclosed is a method for producing lysine ester triisocyanate, which is characterized in that heat treatment is performed at 0 to 200 ° C. and then rectification is performed.

[0004] However, in the above-mentioned method, in view of industrial production, suspension and dispersion of lysine monoalkyl ester trihydrochloride (powder) in a water-immiscible organic solvent, filtration separation, and formation of a filter cake are considered. There are many steps for handling a large amount of powders and slurries such as washing, and furthermore, a detarring step and a rectification step and two distillation steps are required, which is not practically satisfactory.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a simple method for producing a colorless lysine ester triisocyanate.

[0006]

The present invention relates to a compound represented by the general formula (I):

[0007]

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(Wherein R represents alkylene) and phosgene reacted with a triamine represented by the general formula (II):

[0009]

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In a process for producing a lysine ester triisocyanate represented by the formula (wherein R is as defined above), the lysine ester is obtained by reacting a triamine represented by the general formula (I) or a salt thereof with phosgene. Contacting a mixture containing lysine ester triisocyanate represented by the following general formula (II) with activated carbon or a metal halide, and further distilling the mixture.
A method for producing a lysine ester triisocyanate represented by the formula: Hereinafter, the triamine represented by the general formula (I) may be simply referred to as triamine, and the lysine ester triisocyanate represented by the general formula (II) may be simply referred to as lysine ester triisocyanate.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION In the definition of groups in the general formulas (I) and (II), alkylene represents a straight-chain or branched alkylene having 2 to 6 carbon atoms, for example, ethylene,
Propylene, butylene, heptylene, isobutylene, pentylene, hexylene and the like can be mentioned, among which ethylene is preferred.

In the production method of the present invention, examples of the triamine salt used as a raw material include inorganic acid salts such as hydrochloride, sulfate and nitrate, and organic acid salts such as p-toluenesulfonate. Among them, hydrochloride is preferable, and triamine is more preferably trihydrochloride.
Hereinafter, the production method of the present invention will be described in detail.

The starting material triamine or a salt thereof can be produced, for example, according to the method described in JP-A-5-65253. For example, lysine hydrochloride and amino alcohol or its hydrochloride are subjected to an esterification reaction while removing water under reduced pressure under aeration of hydrochloric acid gas, and an alcoholic solvent such as methanol, ethanol, propanol, isopropanol, butanol, etc. Can be used for the reaction with phosgene. Further, if necessary, those subjected to a recrystallization or dehydration operation may be used for the reaction with phosgene.

The reaction of triamine or a salt thereof with phosgene can be carried out, for example, according to the method described in JP-B-60-26775, using aromatic hydrocarbons (benzene, toluene, o-xylene, m-xylene, p-xylene, etc.). ), Chlorinated aromatic hydrocarbons (chlorobenzene, o-dichlorobenzene,
Triamine or a salt thereof is suspended in an inert solvent such as m-dichlorobenzene, p-dichlorobenzene, etc.), a chlorinated aliphatic hydrocarbon (such as trichloroethane), or a chlorinated alicyclic hydrocarbon (such as chlorocyclohexane). The reaction is preferably carried out at 80 to 150 ° C. by passing phosgene through the suspension. After the reaction, the reaction solution is desolvated, if necessary, by distillation under reduced pressure or the like. Phosgene is preferably used in an amount of 5 to 15 equivalents based on the amino group of the triamine or a salt thereof.

Next, the mixture containing the lysine ester triisocyanate obtained by the above reaction is contacted with activated carbon or a metal halide. Activated carbon or metal halide may be added before desolvating the reaction solution.
The method of contact is preferably a batch method,
A packed tower or the like may be used. Any activated carbon can be used as long as it is not a water-containing product, and a commercial product is usually used. Commercially available products include, for example, purified Shirasagi and Shirasagi P manufactured by Takeda Pharmaceutical Co., Ltd., and Taiko SA manufactured by Nimura Chemical Co., Ltd.
1000 and the like.

The metal halide may be of high purity or of industrial grade, and is usually available as a commercial product. In the metal halide, the metal is preferably copper, zinc, aluminum, tin, lead or the like, and the halogen is fluorine, chlorine, bromine or iodine. Specifically, metal chlorides such as zinc chloride, aluminum chloride, and tin chloride are preferable, and among them, zinc chloride is more preferably used.

Activated carbon and a metal halide may be used in combination, and when used together, it is more effective. The amount of activated carbon or metal halide to be used is preferably 0.1 to 10% by weight, more preferably 0.5 to 7% by weight, based on lysine ester triisocyanate. When activated carbon and a metal halide are used in combination, the content is preferably 0.1 to 0.8% by weight, more preferably 0.3 to 0.8% by weight, respectively.
~ 0.6% by weight.

The temperature of the contact with activated carbon or metal halide is preferably 50 to 150 ° C., more preferably 70 to 150 ° C.
To 140 ° C, more preferably 100 to 140 ° C. The contact is usually performed in a nitrogen atmosphere for 30 minutes to 3 hours. The pressure during the contact is
The contact may be performed under normal pressure, or under increased or reduced pressure.

The mixture containing lysine ester triisocyanate obtained by the above-mentioned contact is further distilled, but it is preferable to remove activated carbon or metal halide by filtration or the like before distillation. Distillation can be performed by a conventional method, but thin-film distillation is preferably performed by a molecular still. When performing thin-film distillation, if necessary, reduced-pressure treatment may be performed before thin-film distillation.

The production method of the present invention is a method for producing lysine ester triisocyanate which is suitable for industrial production because the number of steps for handling powder and slurry is small and the number of distillations is small. The lysine ester triisocyanate obtained by the production method of the present invention has high purity, hardly any coloring, and hardly causes coloring with time (such as yellowing).

The lysine ester triisocyanate obtained by the production method of the present invention can be used, for example, in a coating agent for a polycarbonate resin (JP-A-60-63232).
No. Gazette).

[0022]

Example 1: (1) Production of crude lysine diisocyanate β-isocyanate ethyl ester 100 g of lysine β-aminoethyl ester trihydrochloride obtained in Reference Example 1 was mixed with 500 g of o-dichlorobenzene, and
While heating to ° C., phosgene gas was blown in at a flow rate of 3 mol / lysine β-aminoethyl ester trihydrochloride / hour for 12 hours. Thereafter, nitrogen gas was blown in to remove phosgene, and o-dichlorobenzene was distilled off at 1.3 kPa and 50 to 120 ° C. to obtain 100 g of crude lysine diisocyanate β-isocyanate ethyl ester having a purity of 80%.

(2) Purification of crude lysine diisocyanate β-isocyanate ethyl ester To 100 g of crude lysine diisocyanate β-isocyanate ethyl ester obtained in (1), 5 g of activated carbon (Shirasagi P manufactured by Takeda Pharmaceutical Co., Ltd.) was added, and the mixture was heated to 130 ° C. For 2 hours. Thereafter, the activated carbon was removed by filtration, and a falling film molecular distillation machine [Shibata Kagaku Kikai Kogyo Co., Ltd., Shibata molecular distillation apparatus (MS-300 type), the same apparatus was used in the following Examples and Comparative Examples]. At 140 ° C. under a pressure of 6.6 Pa to obtain 60 g of lysine diisocyanate β-isocyanate ethyl ester. The purity of lysine diisocyanate β-isocyanate ethyl ester was 99% or more, and the hue (APHA) was 20.

The purity of the lysine diisocyanate β-isocyanate ethyl ester of Examples 1 to 3 and Comparative Examples 1 and 2 was determined by high performance liquid chromatography (H
PLC). (Preparation of sample for HPLC analysis and its analysis method) 1) About 1.5 ml of aniline is placed in a sample bottle. 2) Further, about 50 mg of lysine diisocyanate β-isocyanate ethyl ester is placed in a sample bottle and weighed. 3) After about 1 ml of acetonitrile is added, the mixture is left for 5 minutes, and 200 mg of benzophenone, which is an internal standard substance, is added. 4) 100 ml of diluting solvent (ethanol / acetonitrile = 2/1)
Is added, and 50 μl of an 85% phosphoric acid aqueous solution is further added to dissolve. 5) Take 1 ml of the above sample solution, dilute with 5 ml of a diluting solvent (ethanol / acetonitrile = 2/1), and analyze by HPLC. (HPLC analysis conditions) Column: YMC A312 (manufactured by YMC Corporation)
6 × 150mm), Column temperature: 35 ° C Mobile phase: Acetonitrile / methanol / 5% phosphoric acid aqueous solution = 4/1/5 (volume ratio) Flow rate: 2 ml / min Detection: UV (240 nm)

Example 2 5 g of zinc chloride was added to 100 g of the crude lysine diisocyanate β-isocyanate ethyl ester obtained in (1) of Example 1
Was added and heated at 130 ° C. for 2 hours. Thereafter, zinc chloride was removed by filtration, and further, distillation was performed at 140 ° C. at a pressure of 6.6 Pa by a falling thin film molecular distillation machine to obtain 65 g of lysine diisocyanate β-isocyanate ethyl ester.
The purity of lysine diisocyanate β-isocyanate ethyl ester was 99% or more and the hue (APHA) was 30.

Example 3 To 100 g of the crude lysine diisocyanate β-isocyanate ethyl ester obtained in (1) of Example 1 was added 0.5 g of activated carbon (Shirasagi P, manufactured by Takeda Pharmaceutical Co., Ltd.) and 0.5 g of zinc chloride.
Heated at 30 ° C. for 2 hours. Then, the activated carbon and zinc chloride were removed by filtration, and further, by a falling film molecular distillation machine, 6.
Distillation was performed at 140 ° C. under a pressure of 6 Pa to obtain 63 g of lysine diisocyanate β-isocyanate ethyl ester. The purity of lysine diisocyanate β-isocyanate ethyl ester was 99% or more, and the hue (APHA) was 20.

As described in Examples 1 to 3, high-purity lysine ester triisocyanate having almost no color can be produced by the production method of the present invention. Comparative Example 1 100 g of the crude lysine diisocyanate β-isocyanate ethyl ester obtained in (1) of Example 1 was heated at 130 ° C. for 2 hours. Then, 6.
Distillation was performed at 140 ° C. under a pressure of 6 Pa to obtain 70 g of lysine diisocyanate β-isocyanate ethyl ester. The purity of lysine diisocyanate β-isocyanate ethyl ester was 97%, and the hue (APHA) was 200.

Comparative Example 2 100 g of the crude lysine diisocyanate β-isocyanate ethyl ester obtained in (1) of Example 1 was heated at 130 ° C. for 4 hours. Then, 6.
Distillation was performed at 140 ° C. under a pressure of 6 Pa to obtain 68 g of lysine diisocyanate β-isocyanate ethyl ester. The purity of lysine diisocyanate β-isocyanate ethyl ester was 97%, and the hue (APHA) was 180.

Reference Example 1 102 g of lysine monohydrochloride and 109 g of ethanolamine were mixed.
Hydrochloric acid gas in an amount equivalent to 1.2 mol / ethanolamine
I blew it over time. Thereafter, while adjusting to 33 kPa at 120 ° C., hydrochloric acid gas was further passed at 0.2 L / mol lysine / minute, and the mixture was maintained for 7 hours. After the reaction, crystallization was performed with a mixed solvent of methanol and n-butanol. Filtration to obtain the residue,
Further drying under reduced pressure at 60 ° C. and 66 Pa gave 100 g of lysine β-aminoethyl ester trihydrochloride.

[0030]

According to the present invention, there is provided a simple method for producing a colorless lysine ester triisocyanate.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Yukitoshi Fukuda 2-3-3, Daikyo-cho, Yokkaichi-shi, Mie Kyowa Yuka Co., Ltd. F-term in Yokkaichi Laboratory (reference) 4H006 AA02 AC55 AD11 AD40 AD51 BC51 BE52

Claims (5)

[Claims] 1. A compound of the general formula (I) (Wherein R represents alkylene) or a phosgene with a triamine represented by the general formula (II): (Wherein R is as defined above) in a method for producing a lysine ester triisocyanate represented by the general formula (I), wherein the triamine represented by the general formula (I) or a salt thereof is reacted with phosgene. Contacting a mixture containing a lysine ester triisocyanate represented by (II) with activated carbon or a metal halide, and further distilling the mixture. Manufacturing method. 2. The method according to claim 1, wherein the triamine salt represented by the general formula (I) is a triamine trihydrochloride. 3. The process according to claim 1, wherein the contact with the activated carbon or the metal halide is carried out at 50 to 150 ° C. 4. The method according to claim 1, wherein the metal halide is a metal chloride. 5. The metal chloride is zinc chloride.
Production method as described.