JP2000063392A - Production of epoxy group-containing phosphonates - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently obtain a high-purity epoxy group-containing phosphonate useful as a flame-retardant, an anticorrosive, etc., in a high yield by reacting a specific phosphine derivative with a prescribed alcohol and oxidizing the reaction product. SOLUTION: A phosphine derivative of formula I (R1 is an alkyl, an aryl or an aralkyl; X1 is a halogen) such as methyldichlorophosphine, etc., is reacted with a terminal unsaturated group-containing alcohol of formula II (Z1 is an alkylene) such as allyl alcohol in the presence of a dehydrohalogenating agent to give a terminal unsaturated group-containing phosphonite of formula III, which is then oxidized to give an epoxy group-containing phosphonate of formula IV such as bis(2,3-epoxypropyl) phenylphosphonate, etc.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a novel method for producing a phosphonate ester having an epoxy group, which is useful as a flame retardant or anticorrosive agent for epoxy resins such as adhesives, electrical insulating materials, paints, and sealing agents. is there.

[0002]

2. Description of the Related Art Epoxy resin is an adhesive, a sealing agent,
It is commonly used in a wide range of fields such as paints. However, not all of the performance expected of epoxy resins is satisfactory, and for example, electrical insulating materials and paints,
Excellent flame retardancy is required in terms of resin processing. Also in the field of paints, epoxy compounds are superior in adhesive strength to other compounds, but have some problems in corrosion resistance and durability. Therefore, it has been attempted to improve the physical properties of epoxy resins by incorporating a curing agent such as a halogen-containing carboxylic acid anhydride or a flame retardant such as an antimony-based compound or a halogen atom-containing compound into the epoxy resin.

However, in recent years, the level of flame retardancy has become stricter in all fields, and high flame retardancy is required, and in particular, flame retardants containing bromine atoms and chlorine atoms, which are trace amounts upon combustion, are applied to the human body. It has been pointed out that toxic dioxins may be generated, and there is an increasing demand for non-halogen flame retardants. As one method for imparting such flame retardancy and anticorrosion properties to epoxy resins, various phosphonate esters having an epoxy group containing no halogen atom have been proposed.

For example, JP-A-02-272014 discloses the following general formula (5);

[0005]

[Chemical 3]

Wherein m = 0 or 1, n = 0, 1 or 2, o = 1, 2 or 3, where m + n + o = 3, and p represents 0, 1 or 2, X represents an O or S atom, R is a C1-4 alkyl group, a C2-3 alkenyl group, an aryl group, an aralkyl group, or a dialkylamino which is bonded directly or through O or S. Group, an alkylarylamino group or a 3-trialkylsilylpropyl group, R'represents O or S ...
A ¹ and A ² may be the same or different,
Each represents a single crystal (probably a single bond error) or a bridge corresponding to R '. ), An epoxy group-containing phosphorus compound represented by the following general formula (6) is disclosed in JP-A 03-84025.

[0007]

[Chemical 4]

(In the formula, R ³ represents an alkyl group, an aminoalkyl group or an aryl group.) And phosphonic acid esters having an epoxy group are disclosed.

As a method for producing the above-mentioned phosphorus compound having an epoxy group, for example, it is produced according to the following reaction formula.

[0010]

[Chemical 5]

(In the formula, R ⁴ represents a linear or branched alkyl group, an aminoalkyl group or an aryl group.)
(Zh.Obschch.Khim, 1984, 54 (4), 768-771, Zh.Obs
chch. Khim, 1984, 54 (10), pp. 2404-2405 and J. Gen. Che.
m.USSR, 1984, 54 (10), p. 2150).

[0012]

However, the above-mentioned conventional method for producing a phosphorus compound having an epoxy group has a low reaction yield of 50 to 80% and is industrially disadvantageous. Therefore,
Development of an industrial method capable of producing a phosphorus compound having an epoxy group containing no halogen atom in a high yield is desired.

Therefore, it is an object of the present invention to provide an industrially advantageous method capable of producing a phosphonate having an epoxy group containing no halogen atom in a high yield.

[0014]

Under such circumstances, the inventors of the present invention have earnestly studied about a method for producing phosphonates having an epoxy group at the terminal, and as a result, have a phosphine derivative and an unsaturated group at the terminal. The inventors have found that a phosphonate ester having an epoxy group can be obtained in a high yield by reacting with an alcohol and then an oxidation reaction, and completed the present invention.

That is, the present invention provides the following general formula (1): X ¹ P (X ¹ ) -R ¹ (1) (wherein R ¹ is a linear or branched alkyl group, aryl group or And a phosphine derivative represented by an aralkyl group and X ¹ represents a halogen atom, and the following general formula (2): CH ₂ ═CH—Z ¹ —OH (2) (wherein Z ¹ is an alkylene chain) Represented by the following general formula (3);

[0016]

[Chemical 6]

(In the formula, R ¹ and Z ¹ are the same as above.) A phosphonous acid ester having an unsaturated group at the terminal is obtained, and then an oxidation reaction is carried out. Formula (4);

[0018]

[Chemical 7]

The present invention provides a process for producing a phosphonate ester having an epoxy group represented by the formula (wherein R ¹ and Z ¹ are the same as above).

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a method for producing a phosphonate ester having an epoxy group according to an embodiment of the present invention will be described. In the present invention, the phosphine derivative represented by the general formula (1) is reacted with an alcohol having an unsaturated bond at the terminal represented by the general formula (2),
A first step of obtaining a phosphonous acid ester having an unsaturated bond at the terminal represented by the general formula (3), and a step of reacting the obtained phosphonous acid ester with an oxidizing agent It consists of two steps.

In the phosphine derivative represented by the general formula (1) which is the starting material for the first step, R ¹ is a linear or branched alkyl group, an aryl group such as a phenyl group, or benzyl. Group, an aralkyl group such as a phenethyl group, and the alkyl group is preferably an alkyl group having 1 to 10 carbon atoms, specifically, a methyl group, an ethyl group,
n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, n-hexyl group, isohexyl group, n-heptyl group, n-octyl group, isooctyl group, n-decyl group, isodecyl group, etc. Is mentioned.
X ¹ represents a halogen atom such as fluorine, chlorine, bromine or iodine. Specific compounds of the phosphine derivative represented by the general formula (1) include methyldichlorophosphine, methyldibromophosphine, ethyldichlorophosphine, ethyldibromophosphine, n-propyldichlorophosphine, n-propyldibromophosphine, isopropyldichloro. Phosphine, isopropyldibromophosphine, n-butyldichlorophosphine, n-butyldibromophosphine, isobutyldichlorophosphine, isobutyldibromophosphine, sec-butyldichlorophosphine, sec-butyldibromophosphine, n-octyldichlorophosphine, n-octyldibromophosphine, Examples thereof include benzenedichlorophosphine and benzenedibromophosphine.

In the alcohol having an unsaturated bond in the terminal group represented by the general formula (2), which is the other starting material in the first step, in the formula, Z ¹ preferably has 1 to 1 carbon atoms.
10 alkylene groups such as methylene, ethylene, trimethylene, tetramethylene, pentamethylene,
Examples include groups such as hexamethylene, propylene, butylene, and hexene. Specific compounds of the alcohol having an unsaturated bond at the terminal represented by the general formula (2) include allyl alcohol, 3-buten-1-ol, 4-
Penten-1-ol, 5-hexen-1-ol, 6
-Hepten-1-ol, 7-octen-1-ol,
Examples include 8-nonen-1-ol and 9-decen-1-ol.

Next, the phosphine derivative represented by the general formula (1) is reacted with an alcohol having an unsaturated bond in the terminal group represented by the general formula (2) in an organic solvent. As the organic solvent, a phosphine derivative represented by the general formula (1) and an alcohol having an unsaturated bond at the terminal represented by the general formula (2) can be dissolved and an inert solvent is used. There is no limitation, for example, dioxane,
Examples include ethers such as tetrahydrofuran and dibutyl ether, and nitriles such as acetonitrile and propionitrile. Further, these organic solvents can be used alone or in combination of two or more.

The molar ratio of the phosphine derivative represented by the general formula (1) to the alcohol represented by the general formula (2) is usually 1 to 5 times the molar amount of the alcohol relative to the phosphine derivative. , And preferably 1 to 1.5 times the molar amount. The reaction temperature is generally 0 to 100 ° C., preferably 40
To 100 ° C., and the reaction time is 30 minutes to 24 hours, preferably 1 to 2 hours.

In the present invention, the reaction can be carried out more smoothly by further carrying out the reaction in the presence of a dehydrohalogenating agent. As the dehydrohalogenating agent,
There is no particular limitation, for example, amines such as trimethylamine and triethylamine, alkali hydroxides such as potassium hydroxide and sodium hydroxide, alkoxides such as sodium methoxide, potassium methoxide, sodium ethoxide and potassium ethoxide, piperidine and pyridine. , Potassium cresolate, and the like. These dehydrohalogenating agents can be used alone or in combination of two or more. The addition amount of these dehydrohalogenating agents is usually 2 to 4 times, preferably 2 to 2.5 times the mol of the phosphine derivative.

After the completion of the reaction in the first step, the phosphonous acid ester represented by the general formula (3) can be obtained in high purity and in high yield by filtration and drying by a conventional method. .

In the next second step, the phosphonous acid ester obtained above is reacted with an oxidizing agent in an organic solvent to give a phosphonic acid ester having an epoxy group represented by the general formula (4). Get kind. Examples of the oxidant include peracid, hydrogen peroxide, silver oxide, chromic acid and the like. These oxidizing agents can be used alone or in combination of two or more. The addition amount of the oxidizing agent is not particularly limited, and is usually 3 to 3 relative to the phosphonous acid ester.
The molar ratio is 0 times, preferably 3 to 5 times.

The reaction solvent is not particularly limited as long as it can dissolve the phosphonous acid esters and the oxidizing agent and is inactive, but examples thereof include aromatic carbonization such as toluene, xylene and benzene. Hydrogen, nitriles such as acetonitrile and propionitrile, chloroform,
Examples thereof include haloalkanes such as methylene chloride, and these are used alone or in combination of two or more. The reaction temperature is usually 0
-40 ° C, preferably around room temperature. After the completion of the reaction, the organic phase is usually washed and dried to obtain the desired phosphonic acid ester having an epoxy group represented by the above general formula (4). The purification operation can be performed by any means.

The reaction of the first step and the second step for producing the phosphonic acid ester having an epoxy group represented by the general formula (4) of the present invention proceeds as shown below.

[0030]

[Chemical 8]

(In the formula, R ¹ represents a linear or branched alkyl group, an aryl group or an aralkyl group, X ¹ and X ² are the same or different and represent a halogen atom, and Z ¹ is an alkylene group. Is shown.)

The above reaction is carried out under relatively warm reaction conditions.
Moreover, since the reaction proceeds in a reaction-controlled manner, the target product can be obtained with high purity and high yield. The phosphonate ester thus obtained can impart good heat resistance, flame retardancy, and anticorrosion property to epoxy resins used in various industries such as coatings, sealing agents, and adhesives industries. .

[0033]

EXAMPLES Next, the present invention will be described in more detail with reference to examples, but these are merely examples and do not limit the present invention. Example 1 Bis (2,3-epoxypropyl) phenylphosphonate
50 equipped with a synthetic stirrer, thermometer, dropping funnel, reflux condenser
In a 0 ml four-necked flask under a nitrogen stream, 10.0 g (55.9 mmol) of benzenedichlorophosphine and 1,4
-Add 100 ml of dioxane, and at room temperature 7.80 g (134 mmol) of allyl alcohol, triethylamine 1
1.3 g (112 mmol) and 1,4-dioxane 1
00 ml of the mixed solution was added dropwise. After the dropping, the mixture was reacted at room temperature for 30 minutes and then refluxed for 30 minutes. The residue was filtered off, the organic solvent and the unreacted raw materials were distilled off under reduced pressure, and 11.2 g (50.5 m) of di2-propenyl phenylphosphonous acid
mol; yield 90.3%) was obtained.

(Identification data for di2-propenyl phenylphosphonous acid) ¹ H-NMR (CDCl ₃ , TMS): δ7.85-7.24 (m, 5H), 6.24
-5.80 (m, 2H), 5.50-5.00 (m, 4H), 4.80-4.48 (m, 4H) IR (neat on KBr disk): 3030 (arom νC-H), 1150 (νO-
C), 992 (νP-O), 910 (δ = CH2) MS (FAB, mNBA): 222 (M ⁺ ).

Next, in a 500 ml four-necked flask equipped with a stirrer, a thermometer, a dropping funnel, and a reflux condenser, under nitrogen flow, 10.0 g (45.0 mmol) of di-2-propenyl phenylphosphonous acid obtained above was obtained. And 300 ml of methylene chloride were added, and metachloroperbenzoic acid 31.
0 g (180 mmol) was added, and the mixture was further reacted at room temperature for 1 hour. The organic phase is a 5% aqueous sodium hydrogen carbonate solution 30
The extract was washed twice with 0 ml and once with water, and then dried over anhydrous sodium sulfate. After removing impurities near the origin by silica gel-ethyl acetate short column chromatography, the solvent was distilled off under reduced pressure, and 11.1 g (41.1) of the desired product, bis (2,3-epoxypropyl) phenylphosphonate.
mmol, yield; 91.3%).

(Identification data for bis (2,3-epoxypropyl) phenylphosphonate) ¹ H-NMR (CDCl ₃ , TMS): δ7.95-7.24 (m, 5H), 3.51
-3.48 (m, 4H), 3.33-3.18 (m, 2H), 2.80-2.71 (m, 2H)
, 2.69 (m, 2H) IR (neat on KBr disk): 3030 (arom νC-H), 1139 (νO-
C), 991 (νP-O), 920 (δ COC) MS (FAB, mNBA): 270 (M ⁺ ).

Example 2 Synthesis of bis (2,3-epoxypropyl) methylphosphonate 50 equipped with a stirrer, thermometer, dropping funnel, and reflux condenser
6.54 g (55.9 mmol) of methyldichlorophosphine and 1,4-under a nitrogen stream in a 0 ml four-necked flask.
100 ml of dioxane was added, and 7.80 g (134 mmol) of allyl alcohol and 1 of triethylamine were added at room temperature.
1.3 g (112 mmol) and 1,4-dixane 10
0 ml of the mixed solution was added dropwise. After the dropping, the mixture was reacted at room temperature for 30 minutes and then refluxed for 30 minutes. After the dropping, the mixture was reacted at room temperature for 30 minutes and then refluxed for 30 minutes. The residue was filtered off, the organic solvent and unreacted raw materials were distilled off under reduced pressure, and 7.87 g (4% of di-2-propenyl methylphosphonous acid phosphonite) was obtained.
9.2 mol, yield 88.0%) were obtained.

(Identification data for di2-propenyl methylphosphonous acid) ¹ H-NMR (CDCl ₃ , TMS): δ 6.24-5.80 (m, 2H), 5.50-5.0
0 (m, 4H), 4.80-4.48 (m, 4H), 2.53 (d, J = 16.5Hz, 3H) IR (neat on KBr disk): 2980 (νC-H), 1149 (νO-C),
992 (νP-O), 910 (δ = CH2) MS (FAB, mNBA): 160 (M ⁺ )

Then, in a 500 ml four-necked flask equipped with a stirrer, a thermometer, a dropping funnel, and a reflux condenser, under nitrogen flow, 7.20 g (45.0 mmol) of di-2-propenyl methylphosphonous acid obtained above was obtained. And methylene chloride 3
Add 00 ml, and metachloroperbenzoic acid 31.0 at room temperature
g (180 mmol) was added, and the mixture was further reacted at room temperature for 1 hour. The organic phase is a 5% aqueous sodium hydrogen carbonate solution 300
After washing twice with ml and once with water, it was dried over anhydrous sodium sulfate. After removing impurities near the origin by silica gel-ethyl acetate short column chromatography,
The solvent was distilled off under reduced pressure, and 7.97 g (38.3 m) of the desired product, methylphosphonate bis (2,3-epoxypropyl).
mol, yield; 85.1%) was obtained.

(Identification data for bis (2,3-epoxypropyl) methylphosphonate) ¹ H-NMR (CDCl ₃ , TMS): δ3.51-3.48 (m, 4H), 3.33-3.18
(m, 2H), 2.80-2.71 (m, 2H), 2.69 (m, 2H), 2.53 (d,
J = 16.5Hz, 3H) IR (neat on KBr disk): 2980 (νC-H), 1147 (νO-C),
993 (νP-O), 920 (δ COC) MS (FAB, mNBA): 208 (M ⁺ )

Example 3 Synthesis of bis (3,4-epoxybutyl) phenylphosphonate 50 equipped with stirrer, thermometer, dropping funnel, reflux condenser
In a 0 ml four-necked flask under a nitrogen stream, 10.0 g (55.9 mmol) of benzenedichlorophosphine and 1,4
-Add 100 ml of dioxane and add 3-butene-1 at room temperature.
-A mixed solution of 9.65 g (134 mmol) of all, 11.3 g (112 mmol) of triethylamine and 100 ml of 1,4-dioxane was added dropwise. After the dropping, the mixture was reacted at room temperature for 30 minutes and then refluxed for 30 minutes. The residue was filtered off, the organic solvent and the unreacted raw materials were distilled off under reduced pressure, and 12.0 g (48.0) of di-3-butenyl phenylphosphonous acid was added.
mmol, yield; 85.9%) was obtained.

(Identification data of di-3-butenyl phenylphosphonous acid) ¹ H-NMR (CDCl ₃ , TMS): δ7.85-7.24 (m, 5H), 6.13-5.
70 (m, 2H), 5.50-5.00 (m, 4H), 3.80-3.51 (m, 4H)
, 2.41-2.10 (m, 4H) IR (neat on KBr disk): 3030 (arom νC-H), 1148 (νO-
C), 991 (νP-O), 910 (δ = CH2) MS (FAB, mNBA): 250 (M ⁺ ).

Then, in a 500 ml four-necked flask equipped with a stirrer, a thermometer, a dropping funnel, and a reflux condenser, under a nitrogen stream, 11.3 g (45.2 mmol) of di-3-butenyl phenylphosphonous acid obtained above was obtained. And methylene chloride 3
Add 00 ml, and metachloroperbenzoic acid 31.0 at room temperature
g (180 mmol) was added, and the mixture was further reacted at room temperature for 1 hour. The organic phase is a 5% aqueous sodium hydrogen carbonate solution 300
After washing twice with ml and once with water, it was dried over anhydrous sodium sulfate. After removing impurities near the origin by silica gel-ethyl acetate short column chromatography,
The solvent was distilled off under reduced pressure, and 11.1 g (37.2 mm) of bis (3,4-epoxybutyl) phenylphosphonate was obtained.
ol, yield; 82.3%) was obtained.

(Identification data for bis (3,4-epoxybutyl) phenylphosphonate) ¹ H-NMR (CDCl ₃ , TMS): δ7.95-7.24 (m, 5H), 3.51-3.
48 (m, 4H), 3.33-3.18 (m, 2H), 2.80-2.21 (m, 8H) IR (neat on KBr disk): 3030 (arom νC-H), 1139 (νO-
C), 991 (νP-O), 920 (δ COC) MS (FAB, mNBA): 298 (M ⁺ ).

[0045]

INDUSTRIAL APPLICABILITY As described above, by using the production method of the present invention, a bifunctional epoxy compound containing a phosphorus atom in the main chain skeleton can be easily synthesized in a high yield by an industrially advantageous method. it can. These compounds can impart good heat resistance, flame retardancy, and corrosion resistance to conventional epoxy resins, and these findings are industrially advantageous.

Claims (2)

[Claims] 1. The following general formula (1); X ¹ P (X ¹ ) -R ¹ (1) (wherein R ¹ represents a linear or branched alkyl group, an aryl group or an aralkyl group. , X ¹ represents a halogen atom) and the following general formula (2): CH ₂ ═CH—Z ¹ —OH (2) (wherein Z ¹ represents an alkylene group). By reacting with an alcohol having an unsaturated group at the end represented by the following general formula (3); (In the formula, R ¹ and Z ¹ are the same as the above.) A phosphonous acid ester having an unsaturated group at the terminal is obtained, and then an oxidative reaction is carried out. ); (In the formula, R ¹ and Z ¹ are the same as the above.) A method for producing a phosphonate ester having an epoxy group. 2. The phosphonic acid having an epoxy group according to claim 1, wherein the reaction between the phosphine derivative and the alcohol having an unsaturated bond at the terminal is carried out in the presence of a dehydrohalogenating agent. Method for producing esters.