JP4815951B2 - New adamantyl ester compounds - Google Patents

Description

  The present invention relates to a novel adamantyl ester compound useful as a raw material monomer for various highly functional materials such as a resist material for fine processing, an optical material, and a heat-resistant material, and a pharmaceutical / agrochemical intermediate.

  Adamantane is a unique molecule having a strong and highly symmetric carbon skeleton, and its derivatives are known to be useful as various highly functional materials and pharmaceutical / agrochemical intermediates. For example, since it is excellent in optical characteristics and heat resistance, it is expected as a material for optical lenses, optical disk substrates, optical fibers, and the like (see Patent Documents 1 to 3). Further, it can also be used as a coating material or paint monomer having excellent weather resistance, chemical resistance, hardness and the like (see Patent Documents 4 and 5). Furthermore, in recent years, since it is excellent in dry etching resistance and transparency, it is known to be useful as a resist material for fine processing (see Patent Document 6).

  With respect to a resist material for microfabrication, with higher integration of semiconductor elements, a higher resolution is required, and improvement for problems such as development defects and line edge roughness has been strongly demanded. As a countermeasure, for example, it has been proposed to improve the solubility of the resist resin in the resist solvent (see Patent Documents 7 and 8). However, since the adamantane skeleton has a rigid structure and high hydrophobicity, it is generally considered that a resist resin containing an adamantane derivative as a monomer component has low solubility in a general resist solvent.

  It has also been proposed to reduce line edge roughness by increasing the uniformity of the resist resin composition (see Non-Patent Document 1). However, when an adamantane derivative is used as a monomer component, a copolymer resin containing a highly polar monomer component is usually used in order to obtain a resist resin having a well-balanced required physical property. That is, a resin is synthesized by copolymerization of a highly hydrophobic adamantane derivative and a monomer component having low hydrophobicity, and thus it is difficult to obtain a resin having a uniform composition.

  Furthermore, in order to obtain stable resist pattern characteristics, it has been proposed to use a derivative having a hydroxyadamantyl group having one or more substituents as a monomer component (see Patent Document 9). However, the adamantyl group into which only the hydroxyl group is introduced is still highly rigid, and the effect of improving the solubility in a resist solvent or the like is not sufficient. In addition, if there are too many hydroxyl groups directly bonded to the adamantane skeleton, the hydrophilicity becomes unnecessarily high. When a monomer component having such a structure is used, the balance of physical properties of the resist resin as a whole is disturbed. An adverse effect is possible.

Under these circumstances, an adamantane derivative that can improve problems such as development defects and line edge roughness without compromising basic characteristics as a resist material for microfabrication such as resolution, dry etching resistance and sensitivity is strongly demanded.
Japanese Examined Patent Publication No. 7-61980 Japanese Patent No. 2774229 Japanese Patent No. 3331121 JP 2000-327950 A JP 2000-327994 A Japanese Patent No. 2881969 JP 2004-300403 A JP-A-2005-068418 JP-A-11-109632 SEMICON JAPAN SEMI Technology Symposium 2002, 3-27

  An object of the present invention is to provide a novel adamantane derivative useful as a raw material monomer for various highly functional materials such as a resist material for microfabrication, an optical material, and a heat-resistant material, and a pharmaceutical / pesticidal intermediate. In particular, in view of the above-described situation, an adamantane derivative that can improve problems such as development defects and line edge roughness without damaging the basic characteristics of the resist such as resolution, dry etching resistance, and sensitivity in the field of fine processing resist materials. The purpose is to provide.

  As a result of intensive studies on the above problems, the present inventors have found an adamantane derivative having a specific structure as a compound expected to be suitable for the purpose, and have reached the present invention. That is, the present invention provides a novel adamantyl ester compound represented by the formula (1).

（式中、Ｒ_１は炭素数１〜４のアルキル基を示し、Ｒ_２は水素原子またはメチル基を示す。Ｘは同一でも異なっても良く、水素原子、ハロゲン基、シアノ基、ヒドロキシル基、炭素数１〜４のアルキル基、炭素数１〜４のアルコキシル基、炭素数１〜４のヒドロキシアルキル基、ハロゲン元素を含む炭素数１〜４のアルキル基、またはエーテル構造を有する炭素数１〜４のアルキル基を示し、ｎは１〜１３の整数を示す。）

(In the formula, R ₁ represents an alkyl group having 1 to 4 carbon atoms, R ₂ represents a hydrogen atom or a methyl group. X may be the same or different, and a hydrogen atom, a halogen group, a cyano group, a hydroxyl group, C1-C4 alkyl group, C1-C4 alkoxyl group, C1-C4 hydroxyalkyl group, C1-C4 alkyl group containing a halogen element, or C1-C1 having an ether structure 4 represents an alkyl group, and n represents an integer of 1 to 13.)

  Since the novel adamantyl ester compound of the present invention has at least one hydroxyl group and alkoxyl group directly bonded to the adamantane skeleton, both hydrophobicity and rigidity derived from the adamantane skeleton are reduced, Compared to the case where only hydroxyl groups are present, the hydrophilicity does not become excessively high, so that it has an appropriate solubility in a resist solvent, a polymerization solvent, or a copolymer component used in producing a resist resin, or It is thought that it has affinity. Therefore, by using a resin containing the novel adamantyl ester compound of the present invention as a monomer component, it is expected that a resist material for microfabrication with less problems such as development defects and line edge roughness can be obtained. In addition, the novel adamantyl ester compound of the present invention can be expected to be used as a raw material monomer for various high-functional materials such as optical materials and heat-resistant materials.

  The novel adamantyl ester compound of the present invention includes, for example, various known esterifications of adamantanols represented by general formula (2) or metal alkoxides thereof and acrylic acids represented by general formula (3) or general formula (4). It can be synthesized by subjecting it to a reaction.

（式中、Ｒ_１、Ｘ、ｎは上記一般式（１）と同様のものを示す。）

(Wherein R ₁ , X and n are the same as those in the general formula (1)).

（式中、Ｒ_２は上記一般式（１）と同様のものを示す。Ｙはヒドロキシル基、アルコキシル基、またはハロゲン基を示す。）

(In the formula, R ₂ represents the same as in the general formula (1). Y represents a hydroxyl group, an alkoxyl group, or a halogen group.)

（式中、Ｒ_２は、上記一般式（１）と同様のものを示す。）

(In the formula, R ₂ represents the same as in the general formula (1).)

    Here, the following compounds can be illustrated as a specific example of General formula (2).

  The type of esterification reaction is not particularly limited. For example, an adamantanol of general formula (2) and a compound in which Y is a hydroxyl group among acrylic acids of general formula (3) are reacted in the presence of an acid catalyst. Dehydration condensation can be performed.

  Hereinafter, the case where the novel adamantyl ester of the present invention is synthesized by the dehydration condensation will be specifically described. However, the synthesis method in the present invention is not limited at all, and can be produced by appropriately adopting various known reactions. Accordingly, the present invention is not limited by the following description.

  When the novel adamantyl ester compound in the present invention is synthesized by dehydration condensation in the presence of an acid catalyst, an organic solvent inert to the reaction is used. Furthermore, in order to remove water by-produced during the reaction, it is desirable to use an organic solvent that azeotropes with water and separates from water. Specific examples of such solvents include aliphatic hydrocarbons such as hexane, heptane, octane, nonane, decane, alicyclic hydrocarbons such as cyclohexane, methylcyclohexane, dimethylcyclohexane, and ethylcyclohexane, benzene, toluene, xylene, and the like. Aromatic hydrocarbons or a mixed solvent thereof can be used. Although the amount of the solvent used varies depending on the type, it is usually about 1 to 500 parts by weight based on the raw material adamantanol, and about 2 to 100 parts by weight is preferable in view of economy and reaction efficiency. Further, the reaction type may be any of batch type, distribution type and semi-batch type. A Dean-Stark water separator or the like can be used to remove by-product water by azeotropic distillation.

  The amount of acrylic acid added during the reaction is preferably about 1 to 30 mol, more preferably 1.5 to 10 mol, based on the raw material adamantanol. When the amount of acrylic acid is less than the above range, the reaction rate and the conversion rate of adamantanol are lowered and the efficiency is poor. On the other hand, when an extremely large amount of acrylic acid is added beyond the above range, adverse effects such as an increase in the amount of by-produced polymer increase, and the efficiency of the reaction and purification decreases.

  As the acid catalyst, those usually used in esterification reaction by dehydration condensation can be used. Specifically, inorganic acids such as hydrochloric acid, sulfuric acid, phosphoric acid, methanesulfonic acid, trifluoromethanesulfonic acid, benzenesulfonic acid are used. And organic acids such as p-toluenesulfonic acid. Further, two or more kinds of acids may be used in combination. The addition amount of the acid catalyst varies depending on the concentration of the reaction substrate in the solution, but is usually added in an amount of about 0.005 to 0.1 mol based on the adamantanol used as the raw material.

  The reaction temperature can be set to an appropriate value as long as the by-produced water can be removed by azeotropic distillation, but is usually about 60 to 150 ° C. in many cases. If the temperature is too low, the reaction rate decreases and becomes inefficient, and if it is too high, the yield of the target product decreases due to polymerization or decomposition. Furthermore, in order to keep the azeotropic temperature within an appropriate range, the reaction system may be depressurized or pressurized.

  In addition, it is desirable to add a polymerization inhibitor such as methylhydroquinone, p-benzoquinone, α-naphthoquinone, p-methoxyphenol, etc. to the reaction solution in order to suppress polymerization. The appropriate addition amount varies depending on the kind of polymerization inhibitor and the amount of acrylic acid used in the reaction, but for example, about 0.0005 to 0.10 mol amount is used based on the acrylic acid added to the reaction system. Moreover, molecular oxygen can also be supplied into the reaction system as a polymerization inhibitor. Molecular oxygen diluted with an inert gas such as nitrogen may be used, or may be supplied as air. Further, two or more kinds of polymerization inhibitors can be mixed and used.

  Since the acid catalyst and unreacted acrylic acid usually remain in the reaction mixture solution, it is preferable to neutralize these with an alkaline aqueous solution after the reaction. Neutralization can be carried out by adding an alkaline aqueous solution to the reaction mixture solution. Specific examples of the alkaline aqueous solution used here include sodium hydroxide, potassium hydroxide, sodium carbonate, sodium bicarbonate, potassium carbonate. Inorganic alkaline aqueous solutions such as potassium hydrogen carbonate and ammonia, and quaternary ammonium salt aqueous solutions such as tetramethylammonium hydroxide and 2-hydroxyethyltrimethylammonium hydroxide. Of these, sodium hydroxide, potassium hydroxide, and sodium carbonate are preferable. In order to prevent the target product from being lost by hydrolysis, the solution temperature during neutralization is preferably maintained at 50 ° C. or lower.

  After neutralization, the target product contained in the organic phase or aqueous phase can be obtained by a process that appropriately combines known methods such as washing, concentration, extraction, adsorption, distillation, filtration, crystallization, recrystallization, and column chromatography. Can be separated. For example, when the target product is present in the organic phase after the neutralization treatment, it can be isolated by subjecting it to column chromatography using silica gel as a stationary phase after concentration and further crystallization. In addition, in order to suppress the loss by the polymerization of the target product, a polymerization inhibitor may be added in the purification process.

  Hereinafter, the embodiments of the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples.

Example 1 (Production of 3-hydroxy-5-methoxy-1-adamantyl methacrylate)
5-methoxy-1,3-adamantanediol 10 g (0.05 mol), methacrylic acid in a 200 ml five-necked flask equipped with a stirrer, thermometer, Dean-Stark water separator, Dimroth condenser, and air inlet tube 13 g (0.15 mol), concentrated sulfuric acid 0.12 g (1.2 mmol), p-methoxyphenol 37 mg (0.3 mmol), and toluene 50 ml were charged and stirred, and air was supplied at 0.1 l / min. Next, the solution was heated and the reaction was continued for 6 hours at reflux while removing by-produced water with a Dean-Stark water separator, and then cooled to room temperature. 100 g of 5% aqueous sodium hydroxide solution was added to the obtained reaction mixture solution, stirred for 10 minutes, and then transferred to a separatory funnel to remove the aqueous phase. The remaining organic phase was washed with ion-exchanged water until neutral, and then concentrated using an evaporator, and the resulting oily liquid was further purified by silica gel column chromatography to obtain the desired 3-hydroxy- 11 g (0.04 mol, 83% yield based on 5-methoxy-1,3-adamantanediol) of 5-methoxy-1-adamantyl methacrylate was obtained.

The analysis results of the product are as follows.
MS (EI): 266 (M ^<+> , calc. 266.15)
¹ H NMR (CDCl ₃ ): δ 6.02 (1H, s), 5.52 (1H, t), 3.26 (3H, s), 1.24-2.44 (17H, m)
¹³ C NMR (CDCl ₃ ): δ 166.31, 137.34, 125.03, 81.08, 74.81, 70.76, 48.77, 48.09, 47.7643.47, 43.01 , 38.82, 38.73, 29.35, 18.24

Example 2 (Production of 3-hydroxy-5-methoxy-1-adamantyl acrylate)
5-methoxy-1,3-adamantanediol 10 g (0.05 mol), acrylic acid in a 200 ml five-necked flask equipped with a stirrer, thermometer, Dean-Stark water separator, Dimroth condenser, and air inlet tube 11 g (0.15 mol), concentrated sulfuric acid 0.12 g (1.2 mmol), p-methoxyphenol 37 mg (0.3 mmol), and toluene 100 ml were charged and stirred, and air was supplied at 0.1 l / min. Next, the solution was heated and the reaction was continued for 4 hours under reflux while removing by-produced water with a Dean-Stark water separator, and then cooled to room temperature. 100 g of 5% aqueous sodium hydroxide solution was added to the obtained reaction mixture solution, stirred for 10 minutes, and then transferred to a separatory funnel to remove the aqueous phase. The remaining organic phase was washed with ion-exchanged water until neutral, and then 2 mg of methylhydroquinone was added as a polymerization inhibitor, and then concentrated with an evaporator while introducing air. The oily liquid thus obtained was further purified by silica gel column chromatography to obtain 9.6 g (0.04 mol, 5-methoxy-1,3) of the desired 3-hydroxy-5-methoxy-1-adamantyl acrylate. -72% yield based on adamantanediol). The product was confirmed by conducting the same analysis as in Example 1.

Example 3 (Production of 3-hydroxy-5-ethoxy-1-adamantyl methacrylate)
5-Ethoxy-1,3-adamantanediol 11 g (0.05 mol), methacrylic acid in a 200 ml five-necked flask equipped with a stirrer, thermometer, Dean-Stark water separator, Dimroth condenser, and air inlet tube 13 g (0.15 mol), 0.12 g (1.2 mmol) of concentrated sulfuric acid, 37 mg (0.3 mmol) of p-methoxyphenol and 50 ml of toluene were charged and stirred, and air was supplied at 0.1 l / min. Next, the solution was heated and the reaction was continued for 6 hours at reflux while removing by-produced water with a Dean-Stark water separator, and then cooled to room temperature. 100 g of 5% aqueous sodium hydroxide solution was added to the obtained reaction mixture solution, stirred for 10 minutes, and then transferred to a separatory funnel to remove the aqueous phase. The remaining organic phase is washed with ion-exchanged water until neutral with ion-exchanged water, then concentrated using an evaporator, and the obtained oily liquid is further purified by silica gel column chromatography to achieve the target. 11 g (0.04 mol, 80% yield based on 5-methoxy-1,3-adamantanediol) of 3-hydroxy-5-ethoxy-1-adamantyl acrylate was obtained. The product was confirmed by conducting the same analysis as in Example 1.

Example 4 (Production of 3-hydroxy-5-ethoxy-1-adamantyl acrylate)
5-Ethoxy-1,3-adamantanediol 11 g (0.05 mol), acrylic acid in a 200 ml capacity 5-neck flask equipped with a stirrer, thermometer, Dean-Stark water separator, Dimroth condenser, and air inlet tube 11 g (0.15 mol), concentrated sulfuric acid 0.12 g (1.2 mmol), p-methoxyphenol 37 mg (0.3 mmol), and toluene 100 ml were charged and stirred, and air was supplied at 0.1 l / min. Next, the solution was heated, and the by-product water was removed by a Dean-Stark water separator, and the reaction was continued at reflux for 5 hours, followed by cooling to room temperature. 100 g of 5% aqueous sodium hydroxide solution was added to the obtained reaction mixture solution, stirred for 10 minutes, and then transferred to a separatory funnel to remove the aqueous phase. The remaining organic phase was washed with ion-exchanged water until neutral, and then 2 mg of methylhydroquinone was added as a polymerization inhibitor, and then concentrated using an evaporator while introducing air. The oily liquid thus obtained was further purified by silica gel column chromatography to obtain 9.1 g (0.04 mol, 5-methoxy-1,3) of the desired 5-ethoxy-3-hydroxy-1-adamantyl acrylate. -68% yield based on adamantanediol). The product was confirmed by conducting the same analysis as in Example 1.

Claims (2)

An adamantyl ester compound represented by the general formula (1).

(In the formula, R ₁ represents an alkyl group having 1 to 4 carbon atoms, R ₂ represents a hydrogen atom or a methyl group. X may be the same or different, and a hydrogen atom, a halogen group, a cyano group, a hydroxyl group, C1-C4 alkyl group, C1-C4 alkoxyl group, C1-C4 hydroxyalkyl group, C1-C4 alkyl group containing a halogen element, or C1-C1 having an ether structure 4 represents an alkyl group, and n represents an integer of 1 to 13.)   The adamantyl ester compound according to claim 1, wherein, in the general formula (1), X is a hydrogen atom and n is 13.