JP4936512B2 - Photocleavable cyclic compound - Google Patents

Description

  The present invention relates to a photocleavable compound containing a photocleavage site in a cyclic structure. More specifically, it relates to a cyclic compound characterized in that the cleavage site is cleaved with light to generate an amino group in the molecule, and can be suitably used as, for example, an amine generator for photoreaction.

  Photoamine generators are compounds that generate amines by light irradiation, and the generated amines can be used for polymer synthesis, crosslinking, and decomposition, and are expected to be applied to UV curable materials and photoresists. .

  However, there are few types of photoamine generators compared to photoacid generators, and at present there is not much freedom in molecular design. Research is currently underway, including not only amine types and generation efficiency, but also practical aspects such as solubility and heat resistance.

  One photoamine generator is O-acyloxime. In previous studies, the acyloxyimino moiety in the O-acyloxime was cleaved by light irradiation and the carbon-ion and imino radicals were generated through decarboxylation, and these radicals were coupled. It is known that imine is formed and this imine hydrolyzes rapidly to primary amine and ketone. Here, since the O-N bond is cleaved relatively easily, O-acyl oxime is a photoamine generator with high photoreactivity and high thermal decomposition temperature and excellent heat resistance.

  O-carbamoyl oxime is also known as a photoamine generator. Similar to O-acyloxime, the ON bond at the carbamoyloxyimino moiety in O-carbamoyloxime is cleaved by light irradiation, and decarboxylation produces amino radicals and imino radicals. These radicals are coupled. Thus, it is known that hydrazone is produced, and this hydrazone is hydrolyzed to become hydrazine and a ketone. It is also known that amino radicals generate primary amines by extracting hydrogen atoms in the reaction system. O-carbamoyl oxime is also an excellent photoamine generator with high photoreactivity.

These reaction mechanisms are described in detail in Non-Patent Document 1 below.
J. et al. Lalevee, X .; Allonas, J. et al. P. Fouassier, H .; Tachi, A .; Izumitani, M .; Shirai and M.M. Tsunooka, J. et al. Photochem. Photobiol. A: Chem. , Vol. 151, 27 (2002).

  However, ketones produced together with amines from O-acyl oximes and O-carbamoyl oximes are eluted into the developer in the process of negative photoresists and cause film loss. In addition, when applied to a UV curable material, there is a possibility that the ketone gradually oozes from the cured product. In addition, when the volatility of the ketone is high, there is a possibility that it is accompanied by an odor or contaminates the optical system of photolithography. Due to such problems, the field of use may be limited when ketones are produced as by-products.

  Accordingly, the present invention has been made in view of the above problems, and an object of the present invention is to provide a photoamine generator that does not generate a ketone that is liberated as a by-product.

  In order to achieve the above object, in a normal photoamine generator, an amine and a ketone generated by a photocleavage reaction are previously connected by a covalent bond, and the photocleavage site is in a cyclic structure. Is designed to be included in

  The photocleavable cyclic compound in the present invention contains a photocleavage site that is excited by light irradiation to cleave the bond. The photocleavable site is an acyloxyimino site or a carbamoyloxyimino site. Thus, it has been found that the photocleavage site is contained in the cyclic structure, so that the ketone produced by the photocleavage reaction is covalently bonded to the amine, and elution and volatilization of the produced ketone can be suppressed, and the present invention. It came to.

あるいはカルバモイルオキシイミノ部位を含有する式２：

で表される環状化合物（但し、式中、Ｘは―（ＣＨ₂）_n―基、脂環式基、アリーレン基、―（ＣＨ₂）_n―基と脂環式基の結合したもの、―（ＣＨ₂）_n―基とアリーレン基の結合したものから選択され、ｎは２〜７の整数、Ｒ¹は芳香族基または置換アルキル基である）に関し、また式１あるいは式２で表される環状化合物を主成分とする、光反応用アミン発生剤を提供する。 That is, the present invention is a compound containing a photocleavage site in a cyclic structure, wherein the photocleavage site is cleaved by light to produce an amino group in the molecule, Cyclic compound represented by Formula 1 contained:

Alternatively, Formula 2 containing a carbamoyloxyimino moiety:

Wherein X is a — (CH ₂ ) _n — group, an alicyclic group, an arylene group, a combination of a — (CH ₂ ) _n — group and an alicyclic group, (CH ₂ ) _n — selected from a combination of a group and an arylene group, where n is an integer of 2 to 7, and R ¹ is an aromatic group or a substituted alkyl group), and is represented by Formula 1 or Formula 2. An amine generator for photoreaction comprising a cyclic compound as a main component is provided.

  According to the UV curing agent or photoresist using an amine generator for photoreaction containing a compound containing a photocleavage site in a cyclic structure as a main component of the present invention, the generated ketone is an amine and an intramolecular molecule. Because it is tied together, it does not cause problems such as odor generation and resist film loss.

  Furthermore, when an amine generator for photoreactions comprising a cyclic compound as a main component in the present invention is used, the efficiency of imine generation by radical recoupling, which is an intermediate process of amine generation, is made higher than that of conventionally known acyclic compounds. Is also possible.

  As the cyclic compound containing a photocleavable site in the cyclic structure of the present invention, a cyclic O-acyl oxime having 7 to 12 ring members and an O-carbamoyl oxime having no ring member limitation are particularly preferably used. Is adjusted as a main component of a UV curing agent or an amine generator for photoreaction for photoresist. Conventionally known methods are used for adjusting the photoreactive amine generator.

  In the present invention, the cyclic compound is a compound in which atoms are linked in a ring by a covalent bond. In the present invention, the ring portion includes a photocleavage site in a part thereof, and examples of components other than the photocleavage site include an aliphatic group, an alicyclic group, and an arylene group. The arylene group includes an aromatic ring and a heterocyclic ring.

  The photosensitive region can also be adjusted by combining the photocleavage site and the chromophore. Examples of chromophores include aromatic rings, substituted aromatic rings, and ketones. These may or may not be incorporated into the annular structure.

  Further, a sensitizer can be added to the system instead of binding the chromophore in the molecule. As a sensitizer for O-acyl oxime and O-carbamoyl oxime, triplet sensitizers are particularly effective, and benzophenone, thioxanthone, Michler ketone, ketobiscoumarin and derivatives thereof are particularly effective.

  In the case of O-acyl oxime, the number of ring members can be 5 or more as a stable compound, but radical coupling is difficult to proceed when the number of ring members is 6 or less, and the bond is cleaved by photoreaction. Even if it occurs, it is difficult to produce an amine, which is not preferable as a photoamine generator. On the other hand, if the number of ring members is too large, the probability that the generated radicals are close to each other decreases, so that radical coupling is difficult to proceed. In addition, a compound having a ring member larger than 12 is difficult to obtain and synthesize raw materials, and is not preferable from these points. In the case of O-carbamoyl oxime, primary amines are produced by hydrogen abstraction, so the number of ring members is not limited as described above. The amine generator for photoreaction of the present invention may be composed of the compound of the above formula 1 or 2 itself, or may be formulated with a suitable inert carrier or excipient.

  Hereinafter, the present invention will be described in detail with reference to examples. The present invention is not limited in any way by this embodiment.

Example 1
[Synthesis of cyclic O-acyl oxime]
(Experimental example 1)
7.5 g (36.3 mol) of 5-benzoylpentanoic acid (Tokyo Kasei), 3.75 g of hydroxylammonium chloride (Wako Pure Chemical Industries) and 30 ml of methanol were placed in a flask, and 15 ml of an aqueous solution containing 5.6 g of KOH was added thereto. The mixture was heated once, cooled to room temperature, and neutralized with 1.2N aqueous hydrochloric acid in an ice bath. The precipitated white solid was recrystallized from toluene to obtain 5.40 g (24.4 mmol) of 6-hydroxyimino-6-phenylheptanoic acid as colorless crystals.

Yield: 67%
Melting point: 116-116.5 ° C
IR (KBr): 1704 cm ⁻¹ (C═O), 2800-3500 cm ⁻¹ (OH)

１．１６ｇ（５．７１ｍｍｏｌ）の８Ｈ−１，２−オキサゾシン-8-オン−４，５，６，７−テトラヒドロ−３−フェニルが得られた。再結晶はシクロヘキサンから行った。
収率：４１ ％
融点：１３５．５−１３６．５ ℃
熱分解温度（ＴＧＡ）：２１４ ℃
ＵＶ（ＣＨ_３ＣＮ）: λ_max２４８ｎｍ（ε１．４×１０４Ｌ・ｍｏｌ^-1・ｃｍ^-1)
ＩＲ（ＫＢｒ）：１７５５ ｃｍ^-1（Ｃ＝Ｏ）、１１２５ｃｍ^-1（Ｃ−Ｏ−Ｃ）
元素分析：計算値 Ｃ₁₂Ｈ₁₃ＮＯ₂; Ｃ: ７０．９２，Ｈ：６．４５，Ｎ：６．８９． 実測値 Ｃ：７１．１９，Ｈ：６．５３，Ｎ：６．８２． (Experimental example 2)
Into the flask was placed 3.06 g (13.6 mmol) of 6-hydroxyimino-6-phenylhexanoic acid, 45 ml of pyridine, and 60 ml of diethyl ether, and 1.20 ml (16.4 mmol) of thionyl chloride while maintaining at -20 to -30 ° C. ) Containing 120 ml of diethyl ether was added dropwise. After stirring at room temperature overnight, the solvent was distilled off with an evaporator. 50 ml of chloroform was added to the precipitate, and this chloroform solution was washed with 1.2N HCl aqueous solution, saturated NaHCO ₃ aqueous solution and saturated brine, and dried over sodium sulfate. After drying, chloroform was distilled off, and the resulting pale yellow solid was separated by column chromatography.

1.16 g (5.71 mmol) of 8H-1,2-oxazosin-8-one-4,5,6,7-tetrahydro-3-phenyl was obtained. Recrystallization was performed from cyclohexane.
Yield: 41%
Melting point: 135.5-136.5 ° C
Thermal decomposition temperature (TGA): 214 ° C
UV (CH ₃ CN): λ _max 248 nm (ε1.4 × 104 L · mol ⁻¹ · cm ⁻¹ )
IR (KBr): 1755 cm ⁻¹ (C═O), 1125 cm ⁻¹ (C—O—C)
Elemental analysis: calculated value C ₁₂ H ₁₃ NO ₂ ; C: 70.92, H: 6.45, N: 6.89. Actual value C: 71.19, H: 6.53, N: 6.82.

Ｏ−フェニルアセチルアセトフェノンオキシム（ＰａＡｐＯ）、Ｏ−フェニルアセチル−２−アセトナフトンオキシム（ＰａＡｎＯ）と比較した（図１）。 [Evaluation of Photoreactivity of Cyclic O-Acyloxime]
(Experimental example 3)
Polymethacrylonitrile and 8H-1,2-oxazocin-8-one-4,5,6,7-tetrahydro-3-phenyl were dissolved in cyclohexanone and spin-coated on a silicon substrate or quartz plate. This substrate was pre-baked on a hot plate at 80 ° C. for 5 minutes to obtain a thin film having a thickness of about 2.0 μm. The resulting thin film was irradiated with light using a low-pressure mercury lamp, and the change in spectrum was measured. The photodecomposition rate is calculated from the C = O stretch band of the infrared spectrum, and is a known photocleavable cyclic compound, formula 4:

O-phenylacetylacetophenone oxime (PaApO) and O-phenylacetyl-2-acetonaphthone oxime (PaAnO) were compared (FIG. 1).

  In FIG. 1, the photoreactivity of the cyclic compound 8H-1,2-oxazocin-8-one-4,5,6,7-tetrahydro-3-phenyl was higher than that of the acyclic PaApO. Moreover, it was lower than PaAnO which has a naphthyl group.

  In the case of light irradiation in the polymethacrylonitrile, the film containing 8H-1,2-oxazosin-8-one-4,5,6,7-tetrahydro-3-phenyl can be irradiated with light. However, when the film containing PaApO was irradiated with light, a odor peculiar to acetophenone was felt.

[Evaluation of cross-linking reaction acceleration]
(Experimental example 4)
Polyglycidyl methacrylate (number average molecular weight 17,000) and 5 mol% photoamine generator based on glycidyl group were dissolved in cyclohexanone and spin-coated on a silicon substrate. When this substrate was pre-baked at 80 ° C. for 5 minutes, a thin film having a thickness of 0.3 μm was obtained. This thin film was irradiated with light with a low-pressure mercury lamp, and then heated on a hot plate at 120 ° C. for 5 minutes. The heated membrane was immersed in tetrahydrofuran (THF) at room temperature for 10 minutes to examine the change in solubility. The film thickness ratio before and after immersion in THF was defined as the insolubilization rate (FIG. 2).

  FIG. 2 shows that the film containing 8H-1,2-oxazocin-8-one-4,5,6,7-tetrahydro-3-phenyl can be formed with much less light irradiation than the film containing PaAnO. It turned out to be insolubilized.

It is a figure showing the comparison of the photoreactivity of the cyclic photoamine generator of this invention, and an acyclic photoamine generator. It is a figure showing the addition effect of the cyclic photoamine generator of this invention and the acyclic photoamine generator in the light and heat insolubilization of polyglycidyl methacrylate.

Claims (2)

Formula 1:

(Wherein, X is - (CH _{2) n} - is a radical, n is 3-7 integer, R ¹ is an aromatic group or a substituted alkyl group)
The photocleavable cyclic compound shown by these.   An amine generator for photoreaction comprising the cyclic compound according to claim 1 as a main component.

Images