KR101295173B1 - Compound having hindered phenol and benzoxazole and process for preparing the same - Google Patents

Abstract

The present invention relates to a compound having a hindered phenol and benzoxazole simultaneously and a method for preparing the same through the reaction of the hindered phenol and benzoxazole.
In addition, the present invention is a compound having a hindered phenol and benzoxazole at the same time can be used as a stabilizer for imparting stability to both heat and ultraviolet light.

Description

 Compound having hindered phenol and benzoxazole and process for preparing the same}

The present invention provides a compound having a hindered phenol and benzoxazole simultaneously and a method for preparing the same. More specifically, the compound having both the hindered phenol and the benzoxazole through the reaction of the hindered phenol and the benzoxazole can be synthesized.

It is generally known that the mechanical, chemical and aesthetic properties of plastics can be compromised under the light effect. Such damage is generally manifested as yellowing, discoloration, pyrolysis or weakening of the material. Thus, one major field of use of light stabilizers is the protection of plastics.

UV stabilizers are added to protect the plastic from damage, not from heat. Since ultraviolet rays cause discoloration and deterioration of plastic properties due to strong energy, UV stabilizer prevents plastics from being decomposed in advance by selectively absorbing ultraviolet rays and converting them into thermal energy or dissipating free radicals generated by decomposition from ultraviolet rays. Do it. Among them, an ultraviolet stabilizer containing a hindered amine or a hindered phenol that dissipates radicals generated by photolysis from ultraviolet rays stops the photooxidation reaction and serves as an excellent stabilizer.

Plastic is also a polymer compound that can be molded by applying heat and pressure. In order to mold plastic beyond its desired properties, a chemical called plastic additives must be added. Plastic additives not only increase the processability during molding of plastics, but also contribute to improving the physical properties and improving the quality, and to provide stability for maintaining the performance of the final product.

Among these plastics, polyamide is a plastic containing an amide bond in the main chain and is widely consumed as a composite material due to its strong durability and heat resistance. When the mixed material is made or manufactured using polyamide, it is made at a high temperature. The heat stabilizer plays a role of minimizing damage due to thermal decomposition of plastic at high temperature.

Efforts to impart stability to the ultraviolet and heat of such plastics has led to the invention of stabilizers made of metals and organic compounds. Although there are already various kinds of stabilizers, metal-based stabilizers, which are not organic compounds, have disadvantages such as toxicity and contamination from an environmental point of view, and it is difficult to give a single compound multifunctional using structural properties.

Therefore, as a stabilizer made of organic compounds, it is required to develop a stabilizer that satisfies both the thermal stability of heat-sensitive materials and the light stability to prevent photolysis through radical absorption.

 The present invention provides a compound having a hindered phenol and benzoxazole simultaneously and a method for preparing the same through the reaction of the hindered phenol and benzoxazole.

The present invention also provides an amide stabilizer that is stable to both heat and ultraviolet light, including a compound having both hindered phenol and benzoxazole.

The present invention provides a compound having a hindered phenol and benzoxazole simultaneously and a method for preparing the same through the reaction of the hindered phenol and benzoxazole.

Compounds having both hindered phenol and benzoxazole are characterized by the following formula (1).

[Formula 1]

In Formula 1

R ₁ is C ₁ -C ₁₂ alkyl;

R ₂ is one selected from hydrogen, C ₁ -C ₁₂ alkyl and C ₁ -C ₁₂ alkoxy,

R ₃ is hydrogen or C ₁ -C ₁₂ alkyl.)

Preferably, the compound having a hindered phenol and benzoxazole simultaneously represented by Formula 1 may be represented by Formula 1 wherein R ₁ is C ₂ -C ₈ and R ₂ or R ₃ is hydrogen.

Compounds having a hindered phenol represented by the formula (1) and benzoxazole at the same time may be prepared by the step of reacting the benzoxazole represented by the formula (2) and the hindered phenol represented by the following formula (3) and the reaction is 12- It may be carried out by heating to reflux for 24 hours.

[Formula 1]

[Formula 2]

(3)

In Formula 1 or Formula 2

R ₁ is C ₁ -C ₁₂ alkyl;

R ₂ is one selected from hydrogen, C ₁ -C ₁₂ alkyl and C ₁ -C ₁₂ alkoxy,

R ₃ is hydrogen or C ₁ -C ₁₂ alkyl.)

In addition, Chemical Formula 2 may be obtained by reacting Chemical Formula 4 with Chemical Formula 5 below.

[Formula 4]

[Chemical Formula 5]

In Formula 4 or Formula 5

R ₁ or R ₂ is C ₁ -C ₁₂ alkyl,

X is halogen.)

Preferably, Chemical Formula 5 may be selected from 6-bromohexanoyl chloride and 4-bromobutanoyl chloride, and the preparation of Chemical Formula 2 may be performed at room temperature for 6-12 hours.

The present invention also provides an amide stabilizer comprising a compound having a hindered phenol and benzoxazole represented by the formula (1) at the same time.

More preferably, the amide stabilizer includes a compound having both hindered phenol and benzoxazole represented by Formula 1 wherein R ₁ is C ₂ -C ₈ and R ₂ or R ₃ is hydrogen.

The present invention provides a compound having a hindered phenol and benzoxazole represented by the formula (1) through the reaction of the hindered phenol and benzoxazole and a method for preparing the same.

In addition, it can be used as an amide stabilizer stable to heat and ultraviolet rays, including a compound having a hindered phenol and benzoxazole represented by the formula (1) according to the present invention.

The present invention provides a compound having a hindered phenol and benzoxazole represented by the following formula (1) through the reaction of the hindered phenol and benzoxazole and a method for preparing the same.

[Formula 1]

In Formula 1

R ₁ is C ₁ -C ₁₂ alkyl;

R ₂ is one selected from hydrogen, C ₁ -C ₁₂ alkyl and C ₁ -C ₁₂ alkoxy,

R ₃ is hydrogen or C ₁ -C ₁₂ alkyl.)

Preferably, the compound having a hindered phenol and benzoxazole simultaneously represented by Formula 1 may be represented by Formula 1 wherein R ₁ is C ₂ -C ₈ and R ₂ or R ₃ is hydrogen.

Compounds having a hindered phenol represented by the formula (1) and benzoxazole at the same time may be prepared by the step of reacting the benzoxazole represented by the formula (2) and the hindered phenol represented by the following formula (3) and the reaction is 12- The reaction may be performed for 24 hours, but may be performed by heating and refluxing for more than 12 hours in order to complete the reaction to increase the yield and at the same time reduce the production of impurities and side reactions.

In addition, the reaction for preparing Formula 1 is not particularly limited as a catalyst after the addition of the hindered phenol to the organic solvent and stirred, but may include potassium hydroxide, potassium carbonate, sodium carbonate, etc., preferably potassium hydroxide Can be used. The organic solvent is also not particularly limited, but may include methylene chloride, chloroform, ethanol and the like, with ethanol being preferred.

[Formula 2]

(3)

In Formula 2 or 3

R ₁ is C ₁ -C ₁₂ alkyl;

R ₂ is one selected from hydrogen, C ₁ -C ₁₂ alkyl and C ₁ -C ₁₂ alkoxy,

R ₃ is hydrogen or C ₁ -C ₁₂ alkyl.)

In addition, Chemical Formula 2 may be obtained by reacting Chemical Formula 4 with Chemical Formula 5 below.

[Formula 4]

[Chemical Formula 5]

In Formula 4 or Formula 5

The definition of R ₁ or R ₂ is the same as the definition of R ₁ , R ₂ in Formula 1,

X is halogen.)

Preferably, Formula 5 may be selected from 6-bromohexanoyl chloride and 4-bromobutanoyl chloride and the preparation of Formula 2 may be carried out at room temperature for 6-12 hours but more preferably for 6 hours Can be performed.

In addition, the catalyst used in the reaction for preparing formula (2) is not particularly limited, and may include triethylamine, pyridine, sodium methoxide, and the like, preferably triethylamine. The organic solvent is also not particularly limited, but may include methylene chloride, chloroform, ethanol and the like, with methylene chloride being preferred.

Formula 4 is not particularly limited, but may be obtained by reacting 2,4-diaminophenol dihydrochloride and salicylic acid.

In addition, the compound having a hindered phenol and benzoxazole represented by the formula (1) of the present invention is particularly useful as an amide stabilizer.

Preferably, the amide stabilizer includes a compound having both hindered phenol and benzoxazole represented by Formula 1 wherein R ₁ is C ₂ -C ₈ and R ₂ is hydrogen.

In this respect, "amide-based stabilizer" in the above and the following description is to be understood as an additive capable of preventing or minimizing degradation by heat or light in the manufacture of plastics including amide bonds.

When using a compound having a hindered phenol and benzoxazole simultaneously represented by the formula (1) as an amide stabilizer may be mixed with other known amide stabilizers.

Compounds having both hindered phenols and benzoxazoles represented by Formula 1 have hindered phenols, and thus can extinguish radicals due to photolysis to act as light stabilizers. It also acts as a light stabilizer because it absorbs high-energy ultraviolet rays, which cause decomposition of polymers due to proton migration in the excited state caused by hydrogen bonds between phenyl groups, and emits energy as green fluorescence with much lower energy.

In addition, the compound having a hindered phenol and benzoxazole at the same time has an amide group in the center and has thermal stability by hydrogen bonding with the amide compound, and can be used as various amide stabilizers by controlling the number of adjacent alkyl groups of the amide bond.

Hereinafter, the synthesis and preparation methods of the compounds according to the present invention will be described in detail with reference to Examples, but the scope of the present invention is not limited by the following Examples.

Preparation Example 1 Preparation of 2- (5-aminobenzo [di] oxazol-2-yl) phenol

6.43 g (32.7 mmol) of 2,4-diaminophenol dihydrochloride and 4.52 g (32.7 mmol) of salicylic acid are dissolved in 150 ml of polyphosphoric acid. Then, the mixture was stirred for 12 hours while maintaining the temperature of 150 ° C. The solution is then cooled to room temperature and poured into ice water to precipitate crystals, which are then neutralized with sodium bicarbonate. The obtained solid was filtered, recrystallized in ethanol and dried to obtain 2.1 g (27%) of 2- (5-aminobenzo [di] oxazol-2-yl) phenol.

¹ H NMR (300 MHz, dmso-d ₆ ) δ = 11.3 (d, 1H, OH), 7.94-6.67 (m, 7H, aromatic-H), 4.52 (m, 2H, NH ₂ )

Preparation Example 2 Preparation of 6-Bromo-ene- (2- (2-hydroxyphenyl) benzo [di] oxazol-5-yl) hexaneamide

2.63 g (11.52 mmol) of 2- (5-aminobenzo [di] oxazol-2-yl) phenol was dissolved in 10 ml of methylene chloride, and 2.41 ml (17.28 mmol) of triethylamine was added while maintaining the temperature at 0 ° C. do. After stirring for 30 minutes, the solution is cooled to room temperature, and 2.46 (11.52 mmol) of 6-bromohexanoyl chloride is slowly added by diluting in 5 ml of methylene chloride. After stirring for 6 hours, the compound is washed with brine and the organic layer is extracted. The excess water was dried over magnesium sulfate and recrystallized from ethanol to give 0.56 g (12%) of 6-bromo-ene- (2- (2-hydroxyphenyl) benzo [di] oxazol-5-yl) hexaneamide. Got it.

¹ H NMR (300 MHz, dmso-d ₆ ) δ = 11.5 (d, 1H, OH), 7.94-6.79 (m, 7H, aromatic-H), 8.03 (s, 1H, NH), 1.29-3.30 (m , 10H, aliphatic-H)

Preparation Example 3 Preparation of 4-bromo-ene- (2- (2-hydroxyphenyl) benzo [di] oxazol-5-yl) butaneamide

4-Bromo-ene- (2- (2-hydroxyphenyl) in the same manner as in Preparation Example 2, except that 2.14 g (11.52 mmol) of 4-bromobutanoyl chloride was used instead of 6-bromohexanoyl chloride 0.95 g (22%) of benzo [di] oxazol-5-yl) butaneamide was obtained.

¹ H NMR (300 MHz, dmso-d ₆ ) δ = 11.2 (d, 1H, OH), 7.52-6.83 (m, 7H, aromatic-H), 8.00 (s, 1H, NH), 1.29-3.32 (m , 6H, aliphatic-H)

Example 1 6- (3,5-Di-tert-butyl-4-hydroxybenzyloxy) -ene- (2- (2-hydroxyphenyl) benzo [di] oxazol-5-yl) Preparation of Hexaneamide

6.8 g (16.92 mmol) of 6-bromo-ene- (2- (2-hydroxyphenyl) benzo [di] oxazol-5-yl) hexaneamide prepared in Preparation Example 2 was dissolved in 20 ml of ethanol. 0.95 g (16.92 mmol) of KOH is added. 2,6-di-tert-butyl-4 (hydroxybenzyloxy) phenol 2g (8.46 mmol) was added to the reaction mixture, heated to reflux for 12 hours, cooled to room temperature, and the precipitated material was filtered. The filtrate was washed with methanol and dried to give 6- (3,5-di-tert-butyl-4-hydroxybenzyloxy) -ene- (2- (2-hydroxyphenyl) benzo [di] oxazole 1.5-g (26%) of -5-yl) hexaneamide was obtained.

¹ H NMR (300 MHz, dmso-d ₆ ) δ = 11.5 (s, 1H, OH), 7.64-6.79 (m, 9H, aromatic-H), 8.03 (s, 1H, NH), 1.29-4.63 (m , 30H, aliphatic-H), 5.1 (d, 1H, OH)

Example 2 4- (3,5-Di-tert-butyl-4-hydroxybenzyloxy) -ene- (2- (2-hydroxyphenyl) benzo [di] oxazol-5-yl) Butaneamide

4-Bromo-ene- (2- (2) prepared in Preparation Example 3 instead of 6-bromo-ene- (2- (2-hydroxyphenyl) benzo [di] oxazol-5-yl) hexaneamide Hydroxyphenyl) benzo [di] oxazol-5-yl) butanamide 6.34 g (16.92 mmol) was prepared in the same manner as in Example 1 except that 4- (3,5-di-tertiary- 0.85 g (19%) of butyl-4-hydroxybenzyloxy) -ene- (2- (2-hydroxyphenyl) benzo [di] oxazol-5-yl) butaneamide was obtained.

¹ H NMR (300 MHz, dmso-d ₆ ) δ = 11.1 (s, 1H, OH), 7.82-6.63 (m, 9H, aromatic-H), 8.00 (s, 1H, NH), 1.23-4.48 (m , 26H, aliphatic-H), 4.98 (d, 1H, OH)

Claims (9)

A compound having a hindered phenol and benzoxazole represented by the following formula (1) simultaneously.
[Formula 1]

In Formula 1
R ₁ is C ₂ -C ₈ alkyl;
R < ₂ > is hydrogen,
R ₃ is hydrogen.) delete A method for preparing a compound having a hindered phenol represented by the general formula (1) and a benzoxazole simultaneously, comprising the step of reacting a benzoxazole represented by the following formula (2) and a hindered phenol represented by the following formula (3).
[Formula 1]

(2)

(3)

In Formulas 1 to 3
R ₁ is C ₂ -C ₈ alkyl;
R < ₂ > is hydrogen,
R ₃ is hydrogen.) The method of claim 3,
A method for preparing a compound having a hindered phenol and a benzoxazole simultaneously represented by Chemical Formula 1, comprising the step of reacting the following Chemical Formula 4 with Chemical Formula 5 to obtain a benzoxazole represented by Chemical Formula 2.
[Chemical Formula 4]

[Chemical Formula 5]

In Formula 4 or Formula 5
R ₁ is C ₂ -C ₈ alkyl,
R < ₂ > is hydrogen,
X is halogen.) The method of claim 3,
Process for preparing a compound having a hindered phenol and benzoxazole represented by the formula (1) carried out for 12-24 hours. 5. The method of claim 4,
The reaction for obtaining the benzoxazole represented by the formula (2) is a method for producing a compound having a hindered phenol and benzoxazole represented by the formula (1) carried out for 6-12 hours at room temperature. 5. The method of claim 4,
Formula 5 is a method for preparing a compound having a hindered phenol and benzoxazole simultaneously represented by the formula (1) is one selected from 6-bromohexanoyl chloride and 4-bromobutanoyl chloride. delete delete