WO2006054446A1

WO2006054446A1 - Method for producing hydroxybenzoate compound

Info

Publication number: WO2006054446A1
Application number: PCT/JP2005/020209
Authority: WO
Inventors: Takashi Ayabe; Yoshinori Negishi; Etsuo Tobita
Original assignee: Adeka Corporation
Priority date: 2004-11-22
Filing date: 2005-11-02
Publication date: 2006-05-26
Also published as: TW200624418A

Abstract

Disclosed is a method for producing 3,5-disubstituted-4-hydroxybenzoate compound with high yield. When a hydroxybenzoate compound is synthesized from a 4-hydroxybenzoic acid which is substituted with R1 at the 3-position and with R2 at the 5-position (R1 and R2 independently represent an alkyl group having 1-12 carbon atoms, a cycloalkyl group, an aryl group, an arylalkyl group or alkylaryl group) and an alcohol expressed as R3OH (R3 group represents an alkyl group having 1-30 carbon atoms or a cycloalkyl group), a titanium compound or a zirconium compound is used as a catalyst and the reaction is carried out at a high temperature for a short time.

Description

Specification

Method for producing hydroxybenzoate baboon compound

Technical field

[0001] The present invention relates to a method for producing a hydroxybenzoate compound in which 3,5-disubstituted 4-hydroxybenzoic acid and an alkyl alcohol are esterified using a titanium compound and Z or a zirconium compound as a catalyst. Background art

[0002] 3, 5 Di-substituted 4-hydroxybenzoate compound (hereinafter referred to as hydroxybenzoate compound) is an additive for organic materials such as synthetic resins, and is excellent in stabilization, particularly in providing light resistance. It is known to show the effect. This hydroxybenzoate compound includes 2,4 di-tert-butylphenol 3,5 di-tert-butyl-4-hydroxybenzoate, 2,4-di-tert-amyl benzene 3,5 di-tert-butyl —4 Hydroxybenzoate, hexadecyl-3,5-ditertiarybutyl-4-hydroxybenzoate, etc. have been proposed.

[0003] As a method for synthesizing these hydroxybenzoate compounds, there are a wide variety of ester compounds such as p-toluenesulfonic acid and ester exchange resins as described in JP-A-60-75446. A known method for improving dealkylation such as detertiated butyl groups, which is a disadvantage, has been proposed by esterification using a strongly acidic gel type ion exchange resin catalyst (see Patent Document 1).

However, this technique has not been able to completely suppress dealkylation, and there has been a problem that the yield during purification is low due to a decrease in yield due to side reactions and the influence of byproducts.

Patent Document 1: Japanese Patent Application Laid-Open No. 60-75446 (Claims 1-4, Example 1)

Disclosure of the invention

Problems to be solved by the invention

[0005] The present invention provides a method for synthesizing a hydroxybenzoate compound that does not cause dealkylation and is excellent in yield.

Means for solving the problem [0006] As a result of intensive studies in view of the current situation, the present inventors have dealkylated 3,5-dialkyl-4-hydroxybenzoic acid and alcohol by esterification using a titanium or zirconium compound as a catalyst. The inventors have found that a hydroxybenzoate compound can be synthesized in a short time and with good yield, and have reached the present invention.

That is, the method for producing the hydroxybenzoate compound of the present invention includes:

When synthesizing a hydroxybenzoate compound represented by the general formula (I) from 4-hydroxybenzoic acid substituted with R ^{2 at the} 5-position and an alcohol having 1 to 30 carbon atoms represented by R ³ OH, The catalyst is characterized in that a titanium compound and Z or zirconium compound are used as the catalyst.

[0008] [Chemical 1]

[Wherein, R ¹ and R ² are each independently an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group, an aryl group, an aryl alkyl group or an alkyl aryl group, and R ³ is a carbon atom] Represents an alkyl group or a cycloalkyl group having a number of 1 to 30.)

The invention's effect

[0010] According to the present invention, a hydroxybenzoate compound can be provided in a high yield in a short time.

BEST MODE FOR CARRYING OUT THE INVENTION

[0011] The present invention provides:

This is a method for producing a hydroxybenzoate compound represented by the general formula (I) from 4-hydroxybenzoic acid substituted with R ^{2 at the} 5-position and an alcohol having 1 to 30 carbon atoms (R ³ OH).

Examples of the hydroxybenzoic acid substituted with R ² at the 3-position and the 5-position used in the present invention are those in which R ³ is substituted with a hydrogen atom in the above formula (I), that is, the terminal is a carboxyl group. .

[0012] In the formula (I), the alkyl groups represented by R ¹ and R ² include methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, pentyl, sec Three pentyl, to Forces such as xyl, heptyl, octyl, etc. As cycloalkyl groups, cyclohexyl and the like as aryl groups, benzyl, naphthyl, etc. As aryl alkyl groups, benzyl, tamil, etc., as alkylaryl groups, Examples include methyl, ethyl and butyral.

[0013] Alcohol having 1 to 30 carbon atoms (R ³ OH) may be linear or branched! /.

Examples of the alkyl group represented by R ³ include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, 2-ethylhexyl, Noel, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, Forces such as hexadecyl, heptadecyl, octadecyl, behexyl, etc.

[0014] Specific examples of the hydroxybenzoate compound represented by the general formula (I) include the following compounds Nos. 1 to 5. However, the present invention is not limited to the following examples.

[0015] [Chemical 2]

Compound No.

0

-C 1 0— G ₁₆ H ₃₃ Compound No. 2

0

G—. Compound No. 3 [0018] [Chemical 5]

Compound No. 4

[0019] [Chemical 6]

Compound No. 5

[0020] Examples of the catalyst used in the present invention include titanium compounds and Z or zirconium compounds.

Specific examples of titanium compounds include alkoxy titanium and condensates thereof. Specific examples of zirconium compounds include alkoxy zirconium and condensates thereof, zirconium oxide carboxylate, zirconium oxychloride, zirconium chloride, Examples thereof include zirconium chloride THF complex, zirconium oxide, zirconium hydroxide, zirconium sulfate, zirconium carbonate, zirconium nitrate, zirconium phosphate, zirconium kaide and the like.

The alkoxy group of these compounds has 1 to 8 carbon atoms, preferably 2 to 6 carbon atoms, and a plurality of alkoxy groups bonded to a metal atom which may be linear or branched may be the same as each other, May be different.

Examples of the alkoxytitanium include tetraethoxytitanium, tetra-n-propoxytitanium, tetraisopropoxytitanium, tetrabutoxytitanium, tetrahexyloxytitanium and the like, and tetraisopropoxytitanium is preferable. The alkoxytitanium condensate is a product in which a titanium atom is bonded in a straight chain, branched chain or network via an oxygen atom, and the remaining group of the titanium atom is substituted with an alkoxy group. Examples of the alkoxyzirconium include tetraethoxyzirconium, tetra- _n- propoxyzidinoreconium, tetraisopropoxydinoreconium, tetrabutoxydinoreconium, tetrahexyloxyzirconium, and the like, and preferably tetrabutoxyzirconium (dialkoxyzirconium). It is also called mutetrabutoxide.) As a condensate of alkoxyzirconium, a zirconium atom is bonded in a linear, branched or network form through an oxygen atom, and the remaining group of the zirconium atom is substituted with an alkoxy group. These can be used in combination.

Examples of the zirconium oxide carboxylate include 2-ethylhexanoic acid zirconium oxide, butyric acid zirconium salt, valeric acid zirconium salt, hexanoic acid zirconium salt, heptanoic acid oxidation. Zirconium, zirconium acetate oxide, zinc stearate oxide and mixtures thereof. These catalysts may be used by dissolving them in a solvent such as mineral spirit as required. Further, a commercially available product, reagent 2-ethyl hexylhexanoate oxide (IV) 'mineral spirit solution (Zr: 12%) manufactured by Wako Pure Chemical Industries, Ltd. may be used.

The titanium compound and the Z or zirconium compound may be supported on a carrier made of an inorganic material such as silica or alumina.

[0021] In the production method of the present invention, the molar ratio of alcohol having 1 to 30 carbon atoms to 1 mol of hydroxybenzoic acid is 0.98 to L: 5 mol, preferably 1.0 to 1.3. Molar ratio.

The catalyst is used in an amount of 0.05 to 5 parts by weight, preferably 0.1 to 3 parts by weight, based on 100 parts by weight of hydroxybenzoic acid.

[0022] In the production method of the present invention, the reaction temperature is 150 to 220 ° C, preferably 160 to 200 ° C. The reaction time becomes shorter as the reaction temperature is higher. However, in order to suppress dealkylation, a low reaction temperature is preferable even in the above temperature range, and a force depending on the combination of hydroxybenzoic acid and alcohol used, etc., is 20 minutes to 24 hours, preferably 3 to 15 hours. is there.

The reaction pressure may be an atmospheric pressure that is not particularly limited, but in order to remove the produced water, when the reaction is carried out using a solvent that is preferably carried out in a reduced pressure reaction, the solvent is refluxed. U, preferred to vacuum.

The reaction atmosphere is preferably in dry air or in an inert gas.

A solvent may be used for the reaction. As the reaction solvent, those which dissolve the raw materials and the catalyst and are inert to the reaction and have a boiling point higher than that of water are preferred. Examples thereof include aliphatic, alicyclic and aromatic hydrocarbons. In addition, in the case where the produced water and the raw material alcohol azeotrope, those capable of eliminating azeotropy can be used.

[0023] The reactor is not particularly limited, such as a stirring tank type or a tube type.

The reaction format may be any of batch, semi-batch and continuous.

The water produced during the esterification reaction is distilled off under reduced pressure. When the produced water azeotropes with alcohol or the reaction solvent, the distillate may be separated by refluxing to separate water, and then returned to the reaction system.

[0024] The hydroxybenzoate compound obtained by the present invention is used as a light fastness imparting agent for various synthetic resins. These synthetic resins include polypropylene, high-density polyethylene, low-density polyethylene, linear low-density polyethylene, _α -olefin polymers such as polybutene-1, poly-3-methylpentene, or ethylene acetate butyl copolymer, ethylene propylene copolymer. Polyolefins such as polymers and copolymers thereof, polychlorinated burs, polysalt-vinylidene, chlorinated polyethylene, chlorinated polypropylene, polyvinylidene fluoride, salty gum rubber, salted two-luoacetic acid butyl copolymer, Salt butyl ethylene copolymer, Salt bis Bull mono salt bis biridene copolymer, Salt bis Bull mono salt bis biuridene monoacetate terpolymer, Vinyl chloride acrylate copolymer, Salt-Rulemaleic acid ester copolymer, Salty-ruby-cyclohexyl maleimi Halogen-containing resin such as copolymer, petroleum resin, coumarone resin, polystyrene, polyacetate butyl resin, acrylic resin resin, styrene and cocoon or (X-methylstyrene and other monomers (for example, maleic anhydride, Copolymer (for example, AS resin, ABS resin, MBS resin, heat-resistant ABS resin, etc.), polymethylmethallate, polybulualcohol Of monomers such as linear aromatic polyesters such as polybule formal, polybulubutyral, polyethylene terephthalate and polytetramethylene terephthalate, aliphatic dicarboxylic acids, aliphatic diols and aliphatic hydroxycarboxylic acids Polyamides such as aliphatic polyesters, liquid crystal polyesters or polyamides, polyphenylene oxide, polyforce prolatatam and polyhexamethylene adipamide, polycarbonate, branched polycarbonate, polyacetal, polyphenylene sulfide, polyurethane, fiber base Thermoplastic resins such as resin and their blends, fluorine resin, silicone resin, phenol resin, urea resin, melamine resin, epoxy resin, unsaturated polyester resin, thermosetting polyurethane, etc. Mention may be made of thermosetting resin. Furthermore, an elastomer such as isoprene rubber, butadiene rubber, acrylonitrile-butadiene copolymer rubber, styrene-butadiene copolymer rubber, or a liquid resin may be used. Also, a polymer alloy may be used.

The hydroxybenzoate compound is used in an amount of 0.01 to 20 parts by weight, preferably 0.05 to 10 parts by weight per 100 parts by weight of the resin.

[0025] Examples of these resins include average molecular weight, molecular weight distribution, density, softening point, crystallinity, proportion of insoluble matter in solvent, degree of stereoregularity, presence of catalyst residues, and types of olefins used as raw materials. Although the degree of the effect of the present invention varies depending on the blending ratio, the type of polymerization catalyst (for example, Lewis acid catalyst, metalocene catalyst, supported catalyst, etc.), etc., any of them is effective. In addition, if these resins are used for applications that require light resistance, they can be used both outdoors and indoors. The shapes of films, sheets, molded products, laminates, etc. It is used regardless of the forming method such as extrusion, roll and press.

[0026] When the hydroxybenzoate compound obtained by the production method of the present invention is applied to a resin, a phenolic acid antioxidant, a phosphorus antioxidant, a thioether antioxidant, if necessary. Stabilization with a hindered amine light stabilizer, ultraviolet absorber or the like is preferred.

[0027] Examples of the above-mentioned phenolic acid oxidizer include 2,6 ditertiary butyl-p-cresol, 2,6 diphenol-4-octadecyloxyphenol, distearyl (3,5 diterephthalate). Tributyl 4-hydroxybenzyl) phosphonate, 1,6 hexamethylenebis [(3,5-ditertiarybutyl-4-hydroxyphenol) propionamide], 4,4, thiobis (6 tert-butyl-m-cresol ), 2, 2, -methylenebis (4-methyl-6 tert-butylphenol), 2, 2, -methylenebis (4-ethyl-6 tert-butylphenol), 4, 4 , -Butylidenebis (6 tert-butyl-m-taresol), 2, 2, ethylidenebis (4,6-di-tert-butylphenol), 2,2, -ethylidenebis (4 tert-butyl-6 tert-butylphenol), 1, 1 , 3 Tris (2-methyl-4 hydroxy-5 tert-butylphenol) butane, 1, 3, 5 tris (2, 6 dimethyl-3 hydroxy-4 tert-butylbenzil) isocyanurate, 1, 3, 5 tris (3,3 5 Di-tert-butyl 4-hydroxybenzyl) isocyanurate, 1, 3, 5 tris (3, 5 di-tert-butyl 4-hydroxybenzyl)-2, 4, 6 Trimethylbenzene, 2 Tertiary butyl 4-methyl-6- (2— Atalyloxy 3-tert-butyl-5-methylbenzyl) phenol, stearyl (3,5-ditertiary butyl-4-hydroxyphenol) propionate, thiodiethylene glycol bis [(3, 5 Ditertiary butyl-4-hydroxyphenol) propionate], 1, 6 hexamethylenebis [(3,5-ditertiarybutyl-4-hydroxyphenol) propionate], bis [3,3-bis (4-hydroxy-) 3-tert-butylphenol) butyric acid] glycolone ester, bis [2 tert-butyl-4-methyl-6- (2 hydroxy-3 tert-butyl-5-methylbenzyl) phenol] terephthalate, 1, 3, 5 Tris [(3,5 di-tert-butyl 4-hydroxyphenol) propio-loxychetyl] isocyanurate, 3,9 bis [1,1-dimethyl 2- {((3 tert-butyl 4-hydroxy-1-5 methylphenol) propio -Luoxy} ethyl] -2,4,8,10-tetraoxaspiro [5,5] undecane, triethylene glycol bis [(3-tert-butyl 4-hydroxy-5-methylphenol) propio Over preparative], and the like, with respect 榭脂 100 parts by weight, 0. 001 to: L0 parts by weight, more preferably, 0.05 to 5 parts by weight is used.

Examples of the phosphoric acid antifouling agent include trisnoylphenylphosphite, tris [2 tert-butyl-4- (3-tert-butyl-4-hydroxy-5-methylphenolthio) 5 methylphenol] phosphite, tridecyl phosphite. Phytite, octyl diphenyl phosphate, di (decyl) monophenyl phosphate, di (tridecyl) pentaerythritol diphosphite, di (noyulferyl) pentaerythritol diphosphite, bis (2,4 ditertiary phenol) Pentaerythritol diphosphite, bis (2,6 ditertiarybutyl-4-methylphenol) pentaerythritol diphosphite, bis (2,4,6 tritertiarybutylfetal) pentaerythritol diphosphite, bis (2 , 4 Dicumyl ferrule) Pentaerythrito Diphosphite, tetra (tridecyl) isopropylidenediphenol diphosphite, tetra (tridecyl) -4,4, -n-butylidenebis (2 tert-butyl-5-methylphenol) diphosphite, hexa (tridecyl) -1, 1, 3 Tris (2-methyl 4-hydroxy-5 tert-butylphenol) butane triphosphite, tetrakis (2, 4-di-tert-butylphenol) biphenol-range phosphonite, 9, 10 dihydrate mouth 9-oxa 10 Phosphaphenanthrene 10 Oxide, 2, 2, -Methylenebis (4,6 tert-butylphenol) —2 Ethylhexyl phosphite, 2, 2, -Methylenebis (4,6 tert-butylphenol) -octadecylphos Phytite, 2, 2, ethylidenebis (4, 6 di-tert-butylphenol) fluorophosphite, tris (2-[(2, 4, 8, 10-tetrakis Butyldibenzo [d, f] [1,3,2] dioxaphosphepine 6yl) oxy] ethyl) amine, 2-ethyl-2-butylpropylene glycol and 2,4,6 tri-tert-butylphenol phosphite And so on.

[0029] Examples of the thioether-based antioxidant include dialkyl thiodipropionates such as dilauryl thiodipropionate, dimyristyl thiodipropionate, distearyl thiodipropionate, and pentaerythritol tetra (j8-alkylmercaptoprop (Pionic acid) esters.

[0030] Examples of the ultraviolet absorber include 2,4-dihydroxybenzophenone, 2hydroxy 4-methoxybenzophenone, 2hydroxy-4-octoxybenzophenone, 5, 5, monomethylene bis (2 hydroxy 2-hydroxybenzophenones, such as 4-methoxybenzophenone); 2- (2'-hydroxy-1 5'-methylphenol) benzotriazole, 2- (2, —hydroxy-3 ', 5, 3-Butylphenol) — 5 Chronobenzoate, 2— (2′-Hydroxy 3 ′ Tertiary Butyl-5 ′ Methylphenol) 5 Chronobenzoate, 2— (2, —Hydroxy-5, — Tertiary octylphenol) benzotriazole, 2- (2,1hydroxy-1 3 ', 5,1 dicumylphenol) benzotriazole, 2,2'-methylenebis (4 tertiary octyl 6- (benzotriazolyl) ) Enol), 2- (2,1-hydroxy-1,3-tert-butyl-5, -carboxyphenol) benzotriazole and other 2- (2, -hydroxyphenol) benzotriazoles; Benzoates such as resorcinol monobenzoate; 2 ethyl 2, ethoxy oxalide, 2 ethoxy 4, 4 Substituted oxalides such as decyloxalide; Cyanacrylates such as ethyl a-cyanol β, β-diphenyl phthalate, methyl 2-cyano 3-methyl 3- (ρ-methoxyphenol) atallate; 2— (2 Hydroxy 4-Otoxyphenyl) 4, 6— Bis (2, 4 Di-tert-butyl) — s Triazine, 2— (2 Hydroxy-4-methoxy) 1, 6 Diphenyl 1-triazine, 2- (2-hydroxy-4-propoxy-5-methylphenol) — 4, 6 bis (2,4 ditert-butylphenol) — s Triaryltriazines such as triazine .

Examples of the hindered amine light stabilizer include 2, 2, 6, 6-tetramethyl-4-piperidyl stearate, 1, 2, 2, 6, 6 pentamethyl-4-piperidyl stearate, 2, 2, 6, 6-tetra Methyl—4-piperidylbenzoate, bis (2, 2, 6, 6-tetramethyl 4-piperidyl) sebacate, tetrakis (2, 2, 6, 6-tetramethyl-4-piperidyl) 1 1, 2, 3, 4 butanetetracarboxylate , Tetrakis (1, 2, 2, 6, 6 Pentamethyl-4 piperidyl) -1, 2, 3, 4 Butanetetracarboxylate, bis (2, 2, 6, 6-tetramethyl-4-piperidyl) 'di (tridecyl) 1, 2, 3, 4 Butanetetracarboxylate, bis (1, 2, 2, 6, 6 pentamethyl—4 piberidyl) .di (tridecyl) —1, 2, 3, 4 Butantella carboxylate, bis ( 1, 2, 2, 4, 4 pentamethi — 4— Piperidyl) —2 Butyl—2— (3,5 Ditertiary butyl-4 Hydroxybenzyl) malonate, 1- (2 Hydroxyethyl)-2, 2, 6, 6-Tetramethyl-4-piberidinol ΖSuccinic acid Jetyl polycondensate, 1, 6 bis (2, 2, 6, 6-tetramethyl-4-piveridylamino) hexane Ζ 2, 4-dichloro-6-morpholino s triazine polycondensate, 1, 6 bis (2, 2, 6 , 6-Tetramethyl-4-piperidylamino) hexane Ζ2, 4-Dichloro-mouth-6 Tertiary polycondensate 1,5,8,12-Tetrakis [2,4-bis (Ν butyl Ν— (2, 2, 6, 6-tetramethyl-4-piperidyl) amino) 1 s triazine-6-yl] -1, 5, 8, 12-therazadodecane, 1, 5, 8, 12-the Lakis (2,4bis (Ν butyl Ν— (1, 2, 2, 6, 6 pentamethyl-4-piperidyl) amino) Riadine 1-yl] 1, 5, 8— 12-tetraazadodecane, 1, 6, 11 tris [2, 4 bis (Ν butyl Ν— (2, 2, 6, 6-tetramethyl-4-piperidyl] ) Amino) 1 s —triazine 1 6-yl] aminoundecane, 1, 6, 11 tris [2, 4 bis (Ν butyl) —N— (1, 2, 2, 6, 6-pentamethyl-1-4-piperidyl) amino) 1-s-triazine-6-yl] hindered amine compounds such as aminoundecane.

[0032] The hydroxybenzoate compound of the present invention contains, as necessary, a nucleating agent such as aluminum P-tert-butylbenzoate, an aromatic phosphate metal salt, dibenzylidene sorbitols, and a halogenated aromatic compound. Flame retardants such as phosphoric acid ester compounds and ammonium phosphate, flame retardant aids such as antimony oxide and melamine compounds, anti-dripping agents such as fluorine and silicon resins, antistatic agents, metal stones Inorganic layered composites such as talc and id mouth talcite, heavy metal deactivators, fillers, pigments, lubricants, foaming agents and the like may be used in combination. The method of adding to the fats can be added separately from these other additives, or the additive mixture can be added in the form of granules, for example. It may be added.

[0033] (Example)

Hereinafter, the present invention will be described in detail by way of examples. However, the present invention is not limited to the examples.

The reaction temperature was 170 ° C (Examples 1 and 2) or 185 ° C (Example 3) at which the catalytic activity of a titanium or zirconium catalyst was obtained, and p-toluenesulfonic acid was 170 ° C. Since the dealkylation reaction was remarkable (over 10%) and unrealistic, it was carried out at 140 ° C. according to known literature.

[0034] (Example 1) (Using alkoxy titanium catalyst)

4-Hydroxy-3,5-ditertiarybutylbenzoic acid 25. Og (0. 100 mol) and hexadeno norenoreconole 27.9 g (0.115 monole) as a solvent, 47.5 g of pseudocumene as a solvent At 100 ° C. with stirring, 0.47 g (0.0019 mol) of tetraisopropoxytitanium was added. Dehydration at 170 ° C under reduced pressure for 10 hours, gas chromatograph showed 4-hydroxy-3,5-ditertiary benzoic acid reaction rate of 99% or more and tert-butyl group elimination Was not detected.

After the reaction, the solvent was removed under reduced pressure at 130 ° C, and 80.7 g of methanol was added at 60 ° C. After cooling to room temperature, 43.6 g of a precipitated white solid (yield after crystallization: 91.8%) was filtered off. The obtained compound has a melting point of 62-63 ° C, and the following absorption was confirmed by infrared absorption spectrum. (Xadecinole 3, 5 ditertiary pentenore 4 hydroxybenzoate).

[0035] The infrared absorption spectrum of the resulting compound showed absorption at the following wavenumber (unit: cm).

3630, 2840—3000, 1710, 1600, 1470, 1440, 1390, 1360, 1300, 123 0, 1140

Example 2 (Using alkoxyzirconium catalyst)

The reaction rate was 99% or more except that tetraisopropoxytitanium in Example 1 was changed to 0.47 g of tetrabutoxyzirconium and the reaction time was changed to 5 hours (reaction rate of 99% or more was detected). The desired product 44. lg (yield 92.9%) was obtained. The melting point and infrared absorption spectrum were consistent with the compound obtained in Example 1.

[0037] (Comparative Example 1) (using p-toluenesulfonic acid catalyst)

4-Hydroxy-3,5 Ditertiarybutylbenzoic acid 25 g (0.1 mol) and hexadecyl alcohol 27.9 g (0.12 mol) were charged with 47.5 g of solvent (pseudocumene) and stirred with p-toluene. Sulfonic acid (hereinafter referred to as PTS) 0.47 g was added. After dehydration under reduced pressure at 140 ° C for 15 hours, when the reaction rate reached 95% by gas chromatography, the formation of 3% dealkylated compound was confirmed, and washing with 24 g of water at 80 ° C was performed. Repeatedly removed PTS. The solvent was removed under reduced pressure at 130 ° C., 80.7 g of methanol was added at 60 ° C., and the mixture was cooled to room temperature, and 38.9 g (yield 82.0%) of a white solid precipitated was separated by filtration. The obtained compound had a melting point of 62-63 ° C., and the infrared absorption spectrum was consistent with the compound obtained in Example 1.

[0038] (Example 3) (Using acid-zirconium carboxylate catalyst)

4-Hydroxy-3,5 Di-tert-butylbenzoic acid 25.0 g (0. 100 mol), hexadecylic alcohol 26.0 g (0. 105 mol), pseudocumene 47.5 g were charged into a 300 ml 5-neck flask and stirred. 0.24 g of reagent 2-ethyl hexyl oxalate (IV) / mineral spirit solution (Zr: 12%) manufactured by Gowako Pure Chemical Industries, Ltd. was added at 100 ° C. Thereafter, the reaction was carried out at 185 ° C. for 6 hours while distilling off water under normal pressure reflux. The reaction rate at this time was 99% or more, and no dealkylated compound was observed. Thereafter, the pressure was reduced at 100 ° C to completely remove the solvent. Further, after cooling, 80.7 g of methanol was added at 60 ° C, and crystallization was performed. After cooling to room temperature, the desired product was isolated. (Yield 90.0%) The melting point was 63 ° C., and the infrared absorption spectrum was consistent with that of the compound obtained in Example 1.

Example No dealkylated compound was detected in Example 2 and Example 3, and 3% of dealkylated compound (mainly hexadecyl 3-tert-butyl 4-hydroxy-benzoate) was detected in Comparative Example 1. By reducing the raw material by dealkylation, and by reducing the crystallization yield of impurities of similar structure in the crystallization process, the yield is reduced in proportion to the production rate of the dealkylated compound. Obviously,

In addition, since the dealkylation reaction does not occur in the production method of the present invention, the reaction time can be shortened compared with the conventional production method because the reaction can be performed at a high temperature.

Claims

Claims In synthesizing a hydroxybenzoate compound represented by the general formula (I) from 4-hydroxybenzoic acid substituted with R2 at the 5-position and an alcohol having 1 to 30 carbon atoms represented by R3OH, titanium A method for producing a hydroxybenzoate compound, comprising using a compound and Z or a zirconium compound.

[Chemical 1]

(Wherein R ¹ and R ² each independently represents an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group, an aryl group, an aryl alkyl group or an alkyl aryl group, and R ³ represents an alkyl group having 1 to Represents 30 alkyl groups or cycloalkyl groups.)

[2] The process for producing a hydroxybenzoate compound according to [ ¹ ], wherein R ¹ and R ² represent a tertiary butyl group and R ³ represents a hexadecyl group.

[3] The process for producing a hydroxybenzoate compound according to claim 1 or 2, wherein the titanium compound is alkoxy titanium.

4. The method for producing a hydroxybenzoate compound according to claim 3, wherein the alkoxytitanium is tetraisopropoxytitanium.

5. The method for producing a hydroxybenzoate compound according to claim 1 or 2, wherein the zirconium compound is alkoxyzirconium.

6. The method for producing a hydroxybenzoate compound according to claim 5, wherein the alkoxyzirconium is tetrabutoxyzirconium.

7. The method for producing a hydroxybenzoate compound according to claim 1 or 2, wherein the zirconium compound is an acid zirconium carbonate.

[8] The method for producing a hydroxybenzoate baboon compound according to claim 7, wherein the zirconium oxide carboxylate is zirconium 2-ethylhexanoate oxide.