KR101061602B1 - Flame retardant phosphapphenanthrene compound and preparation method thereof - Google Patents

Abstract

The present invention relates to a flame retardant phosphaphenanthrene compound and a method for preparing the same, and in more detail, to a phosphaphenanthrene compound which may have various derivatives from a phosphaphenanthrene compound and an arylhalogen compound having a specific structure. It relates to a method for producing efficiently through the oxidization reaction.

Since the phosphapanthanthrene compound of the present invention is carbon-bonded to an aromatic organic molecule, the generation of char is high, and heat resistance and moisture resistance are excellent, and thus it can be easily used as a flame retardant. In addition, when the phosphaphenanthrene compound of the present invention contains a methyl group, since the compatibility with the thermoplastic resin is good, an excellent flame retardant resin composition can be produced.

Flame Retardant, Phosphofenanthrene, Suzuki Reaction

Description

Fire-resistant phosphaphenanthrene compounds and preparation method thereof

The present invention relates to a phosphaphenanthrene compound having a specific structure and a method for producing the same in high purity.

Synthetic polymers are widely used, such as plastics, rubber, fibers, etc., but many of the polymer resins are highly combustible, and thus, the flame retardancy of the polymer resins is an important research subject. The flame retardant resin is in the form of a polymer resin to which an additive having flame retardancy is added, or has been produced by a method of reducing combustibility due to a part of a flame retardant material in the polymer basic skeleton.

In general, since the thermoplastic resin has good processability and excellent mechanical properties, it is required to be flame retardant because it is applied to a large heat dissipating material such as electrical and electronic products, computer housing, and office equipment. As a method of flame retarding the thermoplastic resin, it is common to flame retardant using a flame retardant, a flame retardant and the like. Flame retardants and flame retardants include inorganic phosphorus flame retardants such as halogen flame retardants, polyphosphate flame retardants such as phosphorus and ammonium polyphosphate, organic phosphorus flame retardants represented by triaryl phosphate ester compounds, metal hydroxides or flame retardant antimony oxide and melamine compounds. Etc. have been used alone or in combination.

Among these, organic halogen flame retardants and halogen-containing organic flame retardants have excellent flame retardant effects.However, when halogen flame retardants are used, halogen-based compounds may be volatilized during processing to generate hydrogen halide gas to corrode the mold. In addition, the demand for resins containing non-halogen-based flame retardants has been rapidly expanding due to the human health problems of gases generated during combustion.

Since the phosphate ester flame retardant can form char in the thermoplastic resin, flame retardancy can be imparted by preventing heat from being transferred to the inside. However, when the phosphate ester flame retardant is used alone, there is a problem in reducing the heat resistance of the rubber-modified styrene resin and lacking in flame retardancy, thereby limiting the application of the thermoplastic resin.

The present invention relates to a method for efficiently preparing a phosphapfenanthrene compound that can be used as a non-halogen flame retardant, and the like, US Patent 2007/0173659, Korean Patent Publication No. 2008-0047146, Korean Patent Publication No. 1998-0702544, and the like. The prior art prepares phosphaphenanthrene compounds from biphenyl compounds, and the preparation of derivatives is also concentrated on the derivatization of phosphate itself. However, when biphenyl is used as a starting material as in the prior art, various isomers are generated as a by-product, which not only reduces the yield of the reaction but also has a problem in that it is limited in preparing high purity phosphaphenanthrene.

Accordingly, the present inventors have completed the present invention by finding that a new flame retardant compound can be efficiently produced from the arylhalogen compound through an arylation reaction, thereby making it possible to efficiently produce a phosphaphenanthrene compound having excellent flame retardancy. . That is, the present invention is to provide a phosphapphenanthrene compound having excellent flame retardancy and a method for preparing the same.

The present invention for solving the above problems relates to a phosphapphenanthrene compound, characterized in that represented by the following formula (2).

In Formula 2, R ₁ and R ₂ are the same as or different from each other, an alkyl group of C ₁ to C ₃ , an aryl group of C ₆ to C ₁₈ , or an arylalkyl group of C ₇ to C ₁₈ , and X is hydrogen or chlorine to be.

In addition, an object of the present invention is to provide a method for producing a phosphapphenanthrene compound represented by the following formula (2).

[Formula 2]

In Formula 2, R ₁ and R ₂ are the same as or different from each other, an alkyl group of C ₁ to C ₃ , an aryl group of C ₆ to C ₁₈ , or an arylalkyl group of C ₇ to C ₁₈ , and X is hydrogen or chlorine to be.

The phosphapphenanthrene compound of the present invention is carbon-bonded with an organic molecule to aromatics, and thus has a high generation of char, and is excellent in heat resistance and moisture resistance, and thus can be easily used as a flame retardant. In addition, when the phosphaphenanthrene compound of the present invention contains a methyl group, excellent flame retardant resin composition can be produced because of good compatibility with the thermoplastic resin. In addition, the production method of the present invention can produce a phosphapphenanthrene compound in high yield.

Hereinafter, the present invention described above will be described in more detail.

The phosphaphenanthrene compound represented by Chemical Formula 2 may be reacted with a derivative of various forms to provide a phosphaphenanthrene compound, which is represented by the following Chemical Formula 1, and the phosphaphenanthrene compound may be a thermoplastic resin. It can improve flame resistance and heat resistance.

In Formula 1, R ₁ and R ₂ are the same as or different from each other, an alkyl group of C ₁ to C ₃ , an aryl group of C ₆ to C ₁₈ , or an arylalkyl group of C ₇ to C ₁₈ ;

Q is a C ₁ to C ₆ alkyl group, a C ₁ to C ₆ hydroxymethyl group, a C ₃ to C ₈ alkyl group containing a carboxylic acid, a C ₁ to C ₆ alkoxy group containing a hydroxy group, a hydroquinone group, an aryloxy group,- NHR ³ Or -NR ³ R ⁴ (R ³ and R ^{4 are} H, an alkyl group or a phenyl group of C ₁ to C ₆ ).

In Formula 1, R ₁ and R _{2, which may} be the same as or different from each other, are C ₁ to C ₃ alkyl groups, X is a hydrogen atom, a methyl group, a hydroxymethyl group, a C ₃ to C ₈ alkyl group containing a carboxylic acid, a hydroquinone group, -NHR ³ Or -NR ³ R ⁴ (R ³ and R ^{4 are} H, an alkyl group or a phenyl group of C ₁ to C ₆ ). And, more preferably, R ₁ and R ₂ is a methyl group is good in terms of compatibility with the thermoplastic resin, X is a methyl group, hydroxymethyl group, C ₄ ~ C ₆ alkyl group containing carboxylic acid, hydroquinone group, -NHR ³ Or -NR ³ R ⁴ (R ³ and R ^{4 are} H or an alkyl group of C ₁ to C ₆ ).

Specific examples of the present invention represented by Chemical Formula 1 are the same as the following Chemical Formula 1-a to Chemical Formula 1-d.

Hereinafter will be described in detail with respect to the production method of the phosphaphenanthrene compound of the present invention.

Referring to the manufacturing method of the compound represented by the formula (2),

A compound for preparing a compound represented by the following Chemical Formula 5 by reacting a compound represented by the following Chemical Formula 3 with a compound represented by the following Chemical Formula 4 under a base of K ₃ PO ₄ , Cs ₂ CO ₃ , KF or K ₂ CO ₃ . Stage 1; A second step of preparing a compound represented by Chemical Formula 6 by reacting the compound represented by Chemical Formula 5 with pyridine hydrochloride (Pyridine HCl); A third step of preparing a compound represented by the following Chemical Formula 2b by reacting the compound represented by Chemical Formula 6 with phosphorus trichloride (PCl ₃ ) in the presence of zinc chloride; And a fourth step of preparing a compound represented by Chemical Formula 2a by reacting the compound represented by Chemical Formula 2b with water (H ₂ O) under a toluene solvent, a xylene solvent, or a benzene solvent. A compound may be obtained, and the compound represented by Chemical Formula 1 may be prepared using the compound.

R in Formulas 3 to 6 is R ₁ or R ₂ , which may be the same as or different from each other, an alkyl group of C ₁ to C ₃ , an aryl group of C ₆ to C ₁₈ , or an arylalkyl group of C ₇ to C ₁₈ .

[Formula 2b]

In Formula 2b, R ₁ and R ₂ are the same as or different from each other, and are C ₁ to C ₃ alkyl groups, C ₆ to C ₁₈ aryl groups, or C ₇ to C ₁₈ arylalkyl groups.

(2a)

In Formula 2a, R ₁ and R ₂ are the same as R ₁ and R ₂ of Formula 2b.

In the preparation method, the first step is a temperature (100 ^o C ~ 130 ^o C), palladium catalyst (concentration 0.02 ~ 0.1 mol%), phosphine ligand (0.01 ~ 0.05 mol%) and K ₃ PO ₄ , Cs ₂ It is preferred to react under a base (1 equivalent to 3 equivalents) of CO ₃ , KF or K ₂ CO ₃ .

The second step is preferably reacted using 3-10 equivalents of pyridine hydrogen chloride at a temperature (150 ^o C-220 ^o C).

In the third step, 1 to 3 equivalents of phosphorus trichloride are reacted using 1 to 3 equivalents of phosphorus trichloride under 0.01 to 0.05 mol% of zinc chloride catalyst, and more preferably 1 equivalent of phosphorus trichloride. Do.

In the fourth step, it is more preferable to use a toluene solvent, and it is preferable to use 1 to 5 equivalents of water, and more preferably 1 equivalent.

In addition, the preparation method of the phosphapphenanthrene compound represented by the following formula (1) is a compound represented by the following formula (2) and methyl, formic acid, C ₃ ~ C ₈ 2-methylidene 2-methylidene alkanoic acid, C ₃ ~ C ₈ 2-methylidene alkanedionic acid, benzoquinone, C ₃ ~ C ₁₀ alcohol, C ₁ ~ C ₆ aryl alcohol, NH ₂ R ³ Or NHR ³ R ⁴ (R ³ and R ^{4 are} H, a C ₁ to C ₆ alkyl group or a phenyl group); and a Suzuki reaction to prepare a phosphaphenanthrene compound represented by the following Chemical Formula 1 .

[Formula 2]

In Formula 2, R ₁ and R ₂ are the same as or different from each other, an alkyl group of C ₁ to C ₃ , an aryl group of C ₆ to C ₁₈ , or an arylalkyl group of C ₇ to C ₁₈ , and X is hydrogen or chlorine to be.

[Formula 1]

In Formula 1, R ₁ , R ₂ and Q are the same as described above.

And, the specific example of the manufacturing method of this invention is shown in following Reaction Scheme 1.

Hereinafter, the present invention will be described in more detail based on examples. However, the scope of the present invention is not limited by the following examples.

[Synthesis Example]

Synthesis Example 1 Preparation of Compound Represented by Formula 3

 Synthesis of 1-chloro-2-methoxy-4-methylbenzene

Dissolve 2-chloro-5-methylphenol (54 g, 0.37 mol) and methane iodide (28 g, 0.45 mol) in acetone (400 mL), add potassium carbonate (65 g, 0.374 mol), and then 13 hours At reflux. After the reaction was completed, the mixture was concentrated under reduced pressure to remove acetone, and water and ethyl acetate were added thereto, followed by extraction into an organic layer. The organic layer solution was dried by adding anhydrous forget-me-not, and the product obtained through filtration and distillation under reduced pressure was purified by tube chromatography to obtain 1-chloro-2-methoxy-4-methylbenzene (55 g, white solid, yield 95). %).

¹ H NMR (CDCl ₃ , 300 MHz) : d 7.23 (d, J = 8.7 Hz, 1H), 6.75 (m, 1H), 6.67 (dd, J = 8.7, 2.9 Hz, 1H), 3.83 (s, 3 H), 2.34 (s, 3 H).

Synthesis Example 2 Preparation of Compound Represented by Formula 4

Synthesis of p-tolylboronic acid

4-bromotoluene (10 g, 58.4 mmol) was added to tetrahydrofuran (50 mL), and magnesium (1.4 g, 58 mmol) was added thereto. The resulting solution was refluxed for 3 hours, then trimethyl borate (13 mL, 0.13 mol) was added at -78 ° C. The reaction mixture was stirred at room temperature for 13 hours. After the reaction was terminated, the mixture was diluted with 10% HCl so that the reaction mixture had a pH of 3. The resultant was extracted with ether, the organic layer solution was washed with water sufficiently, and the solvent was distilled off under reduced pressure to obtain p-tolylboronic acid as the target compound (6.9 g, white solid, yield 98%).

Synthesis Example 3 Preparation of Compound Represented by Chemical Formula 5

Synthesis of 4,4′-dimethyl-2-methoxy biphenyl

Dissolve 4,4'-dimethyl-2-methoxybiphenyl (35 g, 0.245 mol) and p-tolylboronic acid (36 g, 0.295 mol) in 1,4-dioxane (300 mL), and palladium Diacetate (1.6 g, 0.012 mol), 2-di- t -butylphosphino-2,4,5-triisopropyl biphenyl (5.8 g, 0.012 mol), and potassium phosphate (104 g, 0.49 mol) Was added. The reaction mixture was stirred at 135 ° C for 18 h. At the end of the reaction, the reaction mixture was extracted with water and ethyl acetate. Purification by column chromatography gave the title compound, 4,4'-dimethyl-2-methoxybiphenyl (45 g, white solid, 93% yield).

¹ H NMR (CdCl _3, 300 MHz) : d 7.41 (d, J = 6.9 Hz, 2H), 7.25 (m, 3H), 6.83 (d, J = 7.8 Hz, 1H), 6.79 (s, 1H), 3.79 (s, 3 H), 2.39 (s, 3 H), 2.38 (s, 3 H).

Synthesis Example 4 Preparation of Compound Represented by Chemical Formula 6

4,4'-dimethyl-2-hydroxy biphenyl

Dimethyl-2-methoxy biphenyl (20 g, 0.09 mol) was added to pyridine hydrochloride (100 g, 0.86 mol) and heated at 200 ° C. for 2 hours. After the reaction was completed, water was added to dissolve the reactant, and ethyl acetate was added thereto to extract the product into the organic layer. The organic layer solution was dried over anhydrous forget-me-not, concentrated under reduced pressure, and purified by tube chromatography to obtain the target compound (17 g, white solid, 95% yield).

¹ H NMR (CdCl _3, 300 MHz): d 9.31 (br s, 1 H), 7.42 (dd, J = 6.4, 1.6 Hz, 2H), 7.18 (d, J = 7.9 Hz, 2H), 7.11 (d , J = 7.9 Hz, 1H), 6.73 (s, 1H), 6.67 (dd, J = 7.9, 1.5 Hz, 1H), 2.32 (s, 3H), 2.24 (s, 3H).

Synthesis Example 5 Preparation of Compound Represented by Chemical Formula 2b

10-chloro-3,8-dimethyl-9,10-dihydro-9-oxa-10-phosphaphenanthrene

4,4'-dimethyl-2-hydroxy biphenyl (22 g, 0.11 mol) was dissolved in phosphorus trichloride (17 g, 0.122 mol), and zinc chloride (0.16 g, 1.1 mmol) was added at 0 ° C. After raising the temperature to room temperature, it was heated to 75 ℃ and stirred for 3 hours. Upon completion of the reaction, phosphorus trichloride was removed by distillation at 120 ° C. and the temperature was raised to 200 ° C. and stirred for 4 hours. After the reaction, the mixture was cooled to 100 ° C, and toluene was added to precipitate and remove a yellow solid. The resulting solution was concentrated under reduced pressure to obtain 10-chloro-3,8-dimethyl-9,10-dihydro-9-oxa-10-phosphaphenanthrene as a target compound (21 g, white solid, 85% yield). . The product does not require a separate purification process and was used as it is in the next reaction.

Synthesis Example 6 Preparation of Compound Represented by Chemical Formula 2a

3,8-dimethyl-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide

10-chloro-3,8-dimethyl-9,10-dihydro-9-oxa-10-phosphaphenanthrene (25 g, 0.095 mol) was dissolved in toluene and water (1.7 g, 0.095 mol) was added thereto. It was then refluxed for 3 hours. After the reaction was completed, it was cooled to room temperature to obtain the target compound (23 g, white solid, yield 98%).

¹ H NMR (CdCl _3, 300 MHz): d 9.01 (br s, 1 H), 7.82 (dd, J = 8.2, 5.4, 1 H), 7.78 (d, J = 8.2 Hz, 1H), 7.2 (dq , J = 15.2, 0.6 Hz, 1H), 7.52 (d, J = 7.51 Hz, 1H), 7.07 (m, 2H), 6.67 (dd, J = 7.9, 1.5 Hz, 1H), 2.32 (s, 3H ), 2.24 (s, 3 H); GC-MS m / z (relative intensity) 226.0 (0.02), 244.0 (M ⁺ , 100).

The phosphaphenanthrene compound of the present invention can increase the heat resistance and flame retardancy of the thermoplastic resin, and is excellent in compatibility with the thermoplastic resin, and can be used as a flame retardant enhancer or flame retardant aid for the thermoplastic resin.

Claims (6)

delete delete delete delete A compound for preparing a compound represented by the following Chemical Formula 5 by reacting a compound represented by the following Chemical Formula 3 with a compound represented by the following Chemical Formula 4 under a base of K ₃ PO ₄ , Cs ₂ CO ₃ , KF or K ₂ CO ₃ . Stage 1; A second step of preparing a compound represented by Chemical Formula 6 by reacting a compound represented by Chemical Formula 5 with pyridine hydrochloride (Pyridine HCl); A third step of preparing a compound represented by the following Chemical Formula 2b by reacting the compound represented by the following Chemical Formula 6 with phosphorus trichloride (PCl ₃ ) in the presence of zinc chloride; And A fourth step of preparing a compound represented by Chemical Formula 2a by reacting the compound represented by Chemical Formula 2b with water (H ₂ O); Method for producing a flame-retardant phosphapphenanthrene compound comprising a; (3)

[Formula 4]

[Chemical Formula 5]

[Formula 6]

[Formula 2b]

(2a)

In Formula 3, 4, 5, 6, 2b, or 2a, R is R ₁ or R ₂ ; R ₁ and R ₂ are the same as or different from each other and are a C ₁ to C ₃ alkyl group, a C ₆ to C ₁₈ aryl group, or a C ₇ to C ₁₈ arylalkyl group. The method according to claim 5, wherein R ₁ and R ₂ are each a methyl group.