WO2010041691A1

WO2010041691A1 - Optical recording medium containing metal complex of squarylium compound

Info

Publication number: WO2010041691A1
Application number: PCT/JP2009/067508
Authority: WO
Inventors: 貴弘澤田; 竜生新見; 豊田　浩; 一太服部; 尚志沖村; 辻田　公二; 山下　智; 大嶋　克則; 宇航須本; 栄治中川
Original assignee: 協和発酵ケミカル株式会社; 日本ビクター株式会社
Priority date: 2008-10-08
Filing date: 2009-10-07
Publication date: 2010-04-15
Also published as: JPWO2010041691A1

Abstract

An optical recording medium using a metal complex of a squarylium compound which exhibits highly sensitive photoresponsiveness to blue violet laser light. Specifically disclosed is an optical recording medium containing a metal complex of a squarylium compound represented by formula (I). (In the formula, R¹ represents an optionally substituted alkyl group or the like; R² represents an optionally substituted alkyl group or the like; and R³ and R⁴ may be the same or different and each represents a hydrogen atom, an optionally substituted alkyl group, an NR⁵R⁶ group (wherein R⁵ and R⁶ may be the same or different and each represents a hydrogen atom, an optionally substituted heterocyclic group or the like) or the like.)

Description

Optical recording medium containing metal complex of squarylium compound

The present invention relates to an optical recording medium containing a metal complex of a squarylium compound.

In recent years, development of an optical recording medium that enables ultra-high density recording using a technique for increasing the numerical aperture NA of the objective lens, a technique for reducing the laser wavelength λ, and the like has been progressing. For example, in order to record video information of HDTV (high definition television) for two hours or more, an optical recording medium having the same size as a DVD and a capacity of at least 23 GB is required. In order to meet these demands, an optical recording medium that records higher density information by using a 405 nm blue-violet laser, setting the NA of the objective lens to 0.85, and reducing the laser spot diameter, so-called Blu-ray Disc (BD) has been developed.
The write-once Blu-ray Disc (BD-R) is required to have various excellent characteristics in terms of recording sensitivity, modulation degree, jitter (jitter), error rate, etc., in addition to the required performance that enables recording and playback. . However, those properties in BD-R using conventional organic dyes are not sufficient.

It is known that a metal complex of a squarylium compound having a pyrazole structure is useful as a dye used for a write-once digital versatile disk (DVD-R) (Patent Document 1). The dye is suitable for recording with a laser beam of about 650 nm used for DVD-R recording, but is not suitable for recording with a laser beam of 405 nm.
It is known that a metal complex of a squarylium compound having a pyrazole structure and an amine structure is useful as a dye for a filter for an electronic display device (Patent Document 2).

International Publication No. 2002/50190 Pamphlet International Publication No. 2006/38685 Pamphlet

An object of the present invention is to provide an optical recording medium or the like using a metal complex of a squarylium compound having a highly sensitive photoresponsiveness to blue-violet laser light.

The present invention provides the following [1] to [12].

[1] Formula (I):

[Wherein, R ¹ represents a hydrogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent, an alicyclic hydrocarbon group which may have a substituent, An aryl group which may have a substituent or a heterocyclic group which may have a substituent, R ² represents a hydrogen atom, a hydroxyl group, a carboxyl group, a halogen atom, a nitro group, a cyano group, a substituent An amino group which may have a substituent, an alkyl group which may have a substituent, an alkoxyl group which may have a substituent, an aralkyl group which may have a substituent, and a substituent. Represents an alicyclic hydrocarbon group which may be substituted, an aryl group which may have a substituent or a heterocyclic group which may have a substituent, and R ³ and R ⁴ are the same or different, Hydrogen atom, optionally substituted alkyl group, substituted Which may be an aralkyl group, which may have a substituent the alicyclic hydrocarbon group, an optionally substituted aryl group, optionally substituted heterocyclic group, or NR ⁵ R ⁶ (wherein R ⁵ and R ⁶ are the same or different and have a hydrogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent, or a substituent. Represents an alicyclic hydrocarbon group which may be substituted, an aryl group which may have a substituent or a heterocyclic group which may have a substituent, and R ³ and R ⁴ are adjacent nitrogen atoms And may form an alicyclic heterocyclic ring which may have a substituent. However, R ³ and R ⁴ do not represent a hydrogen atom at the same time.] An optical recording medium containing a metal complex of a squarylium compound represented by:

[2] R ³ and R ⁴ may be the same or different and each may have a hydrogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent, or a substituent. An alicyclic hydrocarbon group, an optionally substituted aryl group or an optionally substituted heterocyclic group, or R ³ and R ⁴ together with the adjacent nitrogen atom The optical recording medium according to [1], wherein an alicyclic heterocyclic ring optionally having a substituent is formed.

[3] The optical recording medium according to [1], wherein at least one of R ³ and R ⁴ is NR ⁵ R ⁶ (wherein R ⁵ and R ⁶ are as defined above).
[4] The optical recording medium according to [1], wherein one of R ³ and R ⁴ is NR ⁵ R ⁶ (wherein R ⁵ and R ⁶ are as defined above) and the other is a hydrogen atom.

[5] At least one of R ⁵ and R ⁶ is represented by the formula (II):

[Wherein W is a nitrogen atom or C—R ⁷ (wherein R ⁷ is a hydrogen atom, a hydroxyl group, a carboxyl group, a halogen atom, a nitro group, a cyano group, an amino group which may have a substituent, An alkyl group which may have a substituent, an alkoxyl group which may have a substituent, an aralkyl group which may have a substituent, and an alicyclic hydrocarbon which may have a substituent A group, an aryl group which may have a substituent or a heterocyclic group which may have a substituent, and X represents a nitrogen atom or C—R ⁸ (wherein R ⁸ represents the above R ⁷ represents a nitrogen atom or C—R ⁹ (wherein R ⁹ is as defined above for R ⁷ ), and Z represents a nitrogen atom or C—R ¹⁰ (wherein R ⁷ ¹⁰ represents a a) synonymous with the ^{R 7,} when W is ^{C-R 7} X is a ^{C-R 8} R ⁷ and R ⁸ may each form two or hydrocarbon ring which may have a substituent together with the carbon atom adjacent, X is C-R ⁸ Y is C- When R ⁹ is R ⁹ , R ⁸ and R ⁹ may be combined with two adjacent carbon atoms to form an optionally substituted hydrocarbon ring, wherein Y is C—R ⁹ And when Z is C—R ¹⁰ , R ⁹ and R ¹⁰ may be combined with two adjacent carbon atoms to form an optionally substituted hydrocarbon ring]. The optical recording medium according to [3] or [4].
[6] The optical recording medium according to [5], wherein W is a nitrogen atom, X is CR ⁸ , Y is CR ⁹ , and Z is CR ¹⁰ .
[7] The optical recording medium according to [5] or [6], wherein one of R ⁵ and R ⁶ is the formula (II) and the other is a hydrogen atom.

[8] R ¹ and R ² may be the same or different and each may have a hydrogen atom, an alkyl group which may have a substituent, an aryl group which may have a substituent, or a substituent. The optical recording medium according to any one of [1] to [7], which is a heterocyclic group.

[9] The optical recording medium according to any one of [1] to [8], wherein the metal is nickel, cobalt, aluminum, copper, zinc, or iron.
[10] The optical recording medium according to any one of [1] to [8], wherein the metal is nickel or cobalt.

[11] The optical recording medium according to any one of [1] to [10], wherein recording is possible with a recording wavelength of 350 to 530 nm.

[12] Formula (Ia):

[Wherein, R ¹ represents a hydrogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent, an alicyclic hydrocarbon group which may have a substituent, An aryl group which may have a substituent or a heterocyclic group which may have a substituent, R ² represents a hydrogen atom, a hydroxyl group, a carboxyl group, a halogen atom, a nitro group, a cyano group, a substituent An amino group which may have a substituent, an alkyl group which may have a substituent, an alkoxyl group which may have a substituent, an aralkyl group which may have a substituent, and a substituent. Represents an alicyclic hydrocarbon group which may be substituted, an aryl group which may have a substituent or a heterocyclic group which may have a substituent, and R ^5a has a hydrogen atom and a substituent. An optionally substituted alkyl group, an optionally substituted aralkyl group, An alicyclic hydrocarbon group which may have a substituent, an aryl group which may have a substituent or a heterocyclic group which may have a substituent, W represents a nitrogen atom or C— R ⁷ (wherein R ⁷ is a hydrogen atom, a hydroxyl group, a carboxyl group, a halogen atom, a nitro group, a cyano group, an amino group which may have a substituent, or an alkyl group which may have a substituent) , An alkoxyl group which may have a substituent, an aralkyl group which may have a substituent, an alicyclic hydrocarbon group which may have a substituent, or a substituent. Represents an aryl group or an optionally substituted heterocyclic group), X represents a nitrogen atom or C—R ⁸ (wherein R ⁸ has the same meaning as R ⁷ above), and Y represents Represents a nitrogen atom or C—R ⁹ (wherein R ⁹ is as defined above for R ⁷ ), and Z is Nitrogen atom or ^{C-R 10} ^{(wherein, R 10} is a is same meaning as the ^{R 7)} represents, W is the ^{C-R 7} a and X are each ^{R 7} and ^{R 8} when it is ^{C-R 8} A hydrocarbon ring which may have a substituent may be formed together with two adjacent carbon atoms, and when X is C—R ⁸ and Y is C—R ⁹ , R ⁸ and R ⁹ may be combined with two adjacent carbon atoms to form a hydrocarbon ring which may have a substituent, and Y is C—R ⁹ and Z is C—R ¹⁰ . In some cases, R ⁹ and R ¹⁰ may be combined with two adjacent nitrogen atoms to form a hydrocarbon ring which may have a substituent, and a metal complex of a squarylium compound represented by:

[13] The metal complex according to [12], wherein W is a nitrogen atom, X is C—R ⁸ , Y is C—R ⁹ and Z is C—R ¹⁰ .
[14] The metal complex according to [12] or [13], wherein R ^5a is a hydrogen atom.
[15] R ¹ and R ² may be the same or different and each may have a hydrogen atom, an alkyl group which may have a substituent, an aryl group which may have a substituent, or a substituent. The metal complex according to any one of [12] to [14], which is a good heterocyclic group.

[16] The metal complex according to any one of [12] to [15], wherein the metal is nickel, cobalt, aluminum, copper, zinc or iron.
[17] The metal complex according to any one of [12] to [15], wherein the metal is nickel or cobalt.

According to the present invention, it is possible to provide an optical recording medium using a metal complex of a squarylium compound having a highly sensitive photoresponsiveness to blue-violet laser light.

Schematic diagram showing the structure of write-once Blu-ray Disc Schematic showing multipulse modulated recording waveform

101 Substrate 102 Reflective layer 103 Recording layer 104 Transparent protective layer 105 Cover layer 106 Recording / reproducing laser beam

Hereinafter, the compound represented by Formula (I) is referred to as Compound (I). The same applies to the compounds of other formula numbers.

In the definition of each group in the general formula, examples of the alkyl moiety in the alkyl group and the alkoxyl group include a linear or branched alkyl group having 1 to 20 carbon atoms, specifically, a methyl group, an ethyl group, and the like. Propyl group, isopropyl group, butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, isopentyl group, 1-methylbutyl group, 2-methylbutyl group, tert-pentyl group, hexyl group, heptyl group, An octyl group, a nonyl group, a decyl group, an eicosyl group and the like can be mentioned. Among them, those having 1 to 6 carbon atoms are preferable.

Examples of the aralkyl group include an aralkyl group having 7 to 15 carbon atoms, and specific examples include a benzyl group, a phenethyl group, a phenylpropyl group, and a naphthylmethyl group.

Examples of the aryl group include aryl groups having 6 to 14 carbon atoms, and specific examples include a phenyl group, a naphthyl group, an anthryl group, and an azulenyl group.

Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

Examples of the alicyclic hydrocarbon in the alicyclic hydrocarbon group include, for example, a cycloalkane having 3 to 8 carbon atoms, a cycloalkene having 3 to 8 carbon atoms, and a bicyclic or tricyclic condensed 3- to 8-membered ring. And alicyclic hydrocarbons.

Specific examples of the cycloalkane having 3 to 8 carbon atoms include, for example, cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane and the like.

Specific examples of the C3-C8 cycloalkene include, for example, cyclopropene, cyclobutene, cyclopentene, cyclohexene, cycloheptene, cyclooctene and the like.

Specific examples of the bicyclic or tricyclic alicyclic hydrocarbon condensed with a 3- to 8-membered ring include dihydropentalene, dihydroindene, tetrahydronaphthalene, hexahydrofluorene and the like.

Examples of the heterocyclic ring in the heterocyclic group include an aromatic heterocyclic ring and an alicyclic heterocyclic ring.
As the aromatic heterocyclic ring, for example, a 5- or 6-membered monocyclic aromatic heterocyclic ring containing at least one atom selected from a nitrogen atom, an oxygen atom and a sulfur atom is condensed. Examples include bicyclic or tricyclic condensed aromatic heterocycles containing at least one atom selected from a nitrogen atom, an oxygen atom, and a sulfur atom. Specific examples include a pyridine ring, a pyrazine ring, and a pyrimidine ring. , Pyridazine ring, quinoline ring, isoquinoline ring, phthalazine ring, quinazoline ring, quinoxaline ring, naphthyridine ring, cinnoline ring, pyrrole ring, pyrazole ring, imidazole ring, triazole ring, triazine ring, tetrazole ring, thiophene ring, furan ring, thiazole Ring, oxazole ring, indole ring, isoindole ring, indazole ring, benzimidazole ring, benzotri Tetrazole ring, benzothiazole ring, benzoxazole ring, purine ring, carbazole ring.

As the alicyclic heterocycle, for example, a 5- to 8-membered monocyclic alicyclic heterocycle containing at least one atom selected from a nitrogen atom, an oxygen atom and a sulfur atom is condensed. A bicyclic or tricyclic condensed alicyclic heterocyclic ring containing at least one atom selected from a nitrogen atom, an oxygen atom and a sulfur atom, specifically, a pyrrolidine ring, a piperidine ring, Examples include piperazine ring, morpholine ring, thiomorpholine ring, homopiperidine ring, homopiperazine ring, tetrahydropyridine ring, tetrahydroquinoline ring, tetrahydroisoquinoline ring, tetrahydrofuran ring, tetrahydropyran ring, dihydrobenzofuran ring, tetrahydrocarbazole ring and the like.

Examples of the alicyclic heterocycle formed by combining R ³ and R ⁴ with the adjacent nitrogen atom include those containing at least one nitrogen atom among the above alicyclic heterocycles. Specific examples include pyrrolidine ring, piperidine ring, piperazine ring, morpholine ring, thiomorpholine ring, homopiperidine ring, homopiperazine ring, tetrahydropyridine ring, tetrahydroquinoline ring, tetrahydroisoquinoline ring and the like.

Examples of the hydrocarbon ring formed by combining R ⁷ and R ⁸ , R ⁸ and R ⁹ , or R ⁹ and R ¹⁰ together with two adjacent carbon atoms include, for example, non-carbon atoms of 5 to 10 carbon atoms. Examples include saturated hydrocarbon rings, and specific examples include a cyclopentene ring, a cyclohexene ring, a cycloheptene ring, a cyclooctene ring, a benzene ring, and a naphthalene ring.

Examples of the substituent for the alkyl group and the alkoxyl group include, for example, the same or different 1 to 5 substituents, specifically, a hydroxyl group, a carboxyl group, a halogen atom, a nitro group, a cyano group, an alkoxyl group, an alkoxyalkoxyl. Group, alkanoyl group, alkylcarbonyloxy group, alkoxycarbonyl group, aroyl group, aryloxy group, arylcarbonyloxy group, aryloxycarbonyl group, heterocyclic group and the like. Here, the halogen atom, the heterocyclic group, and the alkoxyl group have the same meanings as described above. The two alkoxy moieties of the alkoxyalkoxyl group have the same meaning as the above alkoxyl group, respectively. The alkyl portions of the alkanoyl group, alkylcarbonyloxy group and alkoxycarbonyl group are as defined above. The aryl part of the aroyl group, aryloxy group, arylcarbonyloxy group and aryloxycarbonyl group has the same meaning as the above aryl group.

Examples of the substituent of the amino group include one or two substituents, specifically, an alkyl group, an aralkyl group, an alicyclic hydrocarbon group, an aryl group, and the like. Here, the alkyl group, the aralkyl group, the alicyclic hydrocarbon group, and the aryl group have the same meanings as described above. When two substituents are present, each of the substituents may be the same or different.

Examples of the substituent of the aralkyl group, alicyclic hydrocarbon group, and aryl group include, for example, the same or different 1 to 5 substituents, specifically, a hydroxyl group, a carboxyl group, a halogen atom, a nitro group, Cyano group, optionally substituted alkyl group, optionally substituted alkoxyl group, aralkyl group, alkanoyl group, alkylcarbonyloxy group, alkoxycarbonyl group, aryl group, aroyl group, aryloxy Group, an arylcarbonyloxy group, an aryloxycarbonyl group, a heterocyclic group, an amino group which may have a substituent, and the like. Here, a halogen atom, an alkyl group which may have a substituent, an alkoxyl group which may have a substituent, an aralkyl group, an alkanoyl group, an alkylcarbonyloxy group, an alkoxycarbonyl group, an aryl group, an aroyl group , Aryloxy group, arylcarbonyloxy group, aryloxycarbonyl group, heterocyclic group and optionally substituted amino group have the same meanings as described above.

Examples of the substituent of the heterocyclic group when R ¹ , R ² , R ³ , R ⁴ , R ⁷ , R ⁸ , R ⁹ or R ¹⁰ is a heterocyclic group include, for example, an aralkyl group and an alicyclic hydrocarbon Examples of the group and the substituent of the aryl group include the same functional groups exemplified above.

Examples of the substituent of the heterocyclic group when R ⁵ , R ⁶ or R ^5a is a heterocyclic group may include a hydroxyl group, a carboxyl group, a halogen atom, a nitro group, a cyano group, and a substituent. A good amino group, an alkyl group which may have a substituent, an alkoxyl group which may have a substituent, an aralkyl group which may have a substituent, a fat which may have a substituent Examples thereof include a cyclic hydrocarbon group, an aryl group which may have a substituent, and a heterocyclic group which may have a substituent. Here, a halogen atom, an amino group which may have a substituent, an alkyl group which may have a substituent, an alkoxyl group which may have a substituent, or a substituent. A good aralkyl group, an alicyclic hydrocarbon group which may have a substituent and an aryl group which may have a substituent have the same meanings as described above, and an optionally substituted heterocycle The group has the same meaning as that when R ¹ , R ² , R ³ , R ⁴ , R ⁷ , R ⁸ , R ⁹ or R ¹⁰ is a heterocyclic group which may have a substituent.

Examples of the substituent for the alicyclic heterocyclic ring formed by combining R ³ and R ⁴ with the adjacent nitrogen atom include those exemplified above as the substituent for the aralkyl group, alicyclic hydrocarbon group, and aryl group. And the same functional groups as those described above.

Examples of the substituent of the hydrocarbon ring formed by R ⁷ and R ⁸ , R ⁸ and R ⁹ , or R ⁹ and R ¹⁰ together with two adjacent carbon atoms include aralkyl groups, Examples of the substituent of the cyclic hydrocarbon group and aryl group are the same as the functional groups exemplified above.

Examples of the metal in the metal complex include aluminum, ruthenium, osmium, iron, platinum, zinc, beryllium, copper, nickel, chromium, cobalt, manganese, iridium, vanadium, titanium, etc., among which nickel, cobalt, aluminum, Copper, zinc and iron are preferred.
In compound (I), when at least one of R ³ and R ⁴ is NR ⁵ R ⁶ , one of R ³ and R ⁴ is NR ⁵ R ⁶ , the other is a hydrogen atom, and R ⁵ and R 4 ^It is preferable that one of ⁶ is the formula (II) and the other is a hydrogen atom. Here, formula (II) is as defined above.
In compound (Ia), R ^5a is preferably a hydrogen atom.

Compound (I) is, for example, reaction formula (a):

(Wherein R ¹ , R ² , R ³ and R ⁴ are as defined above). Specifically, the compound (III) or a salt thereof and the compound (IV) or a salt thereof, if necessary, in the presence of an acid catalyst in an amount of 0.1 to 1.5-fold moles relative to the compound (III) The compound (I) can be produced by reacting at 40 to 140 ° C. for 0.5 to 30 hours.
The amount of compound (IV) or a salt thereof used is preferably 1 to 5 times the molar amount relative to compound (III) or a salt thereof.

When at least one of R ³ and R ⁴ is NR ⁵ R ⁶ (wherein R ⁵ and R ⁶ are as defined above), the reaction temperature is preferably 40 to 100 ° C.

R ³ and R ⁴ are the same or different and are each a hydrogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent, or an alicyclic which may have a substituent. When it is a hydrocarbon group, an aryl group which may have a substituent or a heterocyclic group which may have a substituent (provided that R ³ and R ⁴ do not represent a hydrogen atom at the same time), The reaction temperature is preferably 80 to 140 ° C. Here, an alkyl group which may have a substituent, an aralkyl group which may have a substituent, an alicyclic hydrocarbon group which may have a substituent, and a substituent. The aryl group and the heterocyclic group which may have a substituent are as defined above.

Examples of the salt of compound (III) include potassium salt and sodium salt.
Examples of the salt of compound (IV) include hydrochloride, sulfate, p-toluenesulfonate, methanesulfonate, and the like.
Examples of the acid catalyst include sulfuric acid, p-toluenesulfonic acid, methanesulfonic acid and the like.

Compound (III) is a diester of squaric acid or a dihalide of squaric acid and a compound of formula (V):

(Wherein R ¹ and R ² have the same meanings as described above), and a compound represented by the known method, for example, the method described in WO 01/44233 pamphlet or the like. Can be obtained. Compound (V) can be obtained as a commercial product or can be obtained by publicly known methods, for example, the Chemical Society of Japan, New Experimental Chemistry Course, Volume 14, “Synthesis and Reaction of Organic Compounds IV Heterocyclic Compounds”, Maruzen Co., Ltd. Company, 1978, p. 2154, Chemistry, 1964, 26, p. 333, Journal of Organic Chemistry, 1957, Vol. 22, p. 780, Chemical & Pharmaceutical Bulletin, 1981, Vol. 29, No. 1, p. 244, Journal of Heterocyclic Chemistry, 1980, Vol. 17, No. 2, p. 389, Liebigs Annalen der Chemie, 1985, Vol. 1, p. 78, Journal of the Chemical Society. Perkin Transactions. 1, 1983, Volume 2, p. 325, Journal of the Indian Chemical Society, 1980, vol. 57, p. 1108, Journal of Organic Chemistry, 1979, vol. 44, p. It can be obtained by manufacturing according to the method described in 4597 and the like.

A compound (IV) in which at least one of R ³ and R ⁴ is NR ⁵ R ⁶ (wherein R ⁵ and R ⁶ have the same meanings as described above) is obtained as a commercial product, Known methods, for example, Journal of Medical Chemistry, 1985, Vol. 28, p. It can be obtained by manufacturing according to the method described in 1394 or the like.

R ³ and R ^{4 in the} compound (IV) are the same or different and have a hydrogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent, or a substituent. An alicyclic hydrocarbon group that may be substituted, an aryl group that may have a substituent, or a heterocyclic group that may have a substituent (provided that R ³ and R ⁴ simultaneously represent a hydrogen atom; May be obtained as a commercial product or may be obtained by a known method such as JP-A-48-39454, JP-A-63-253056, WO95 / 7888, Tetrahedron, 2005. Year, Vol. 61, No. 24, p. 5725, Journal of the Chemical Society, Chemical Communications, 1990, Vol. 12, p. It can obtain by manufacturing according to the method of 869 grade | etc.,. Here, an alkyl group which may have a substituent, an aralkyl group which may have a substituent, an alicyclic hydrocarbon group which may have a substituent, and a substituent. The aryl group and the heterocyclic group which may have a substituent are as defined above.

Examples of the solvent include alcohol solvents such as ethanol, propanol, 2-propanol, butanol and octanol, a mixed solvent of the alcohol solvent (20% by volume or more) and benzene, toluene or xylene, acetonitrile and the like.
After the reaction, if necessary, the compound (I) may be purified by methods usually used in organic synthetic chemistry (various column chromatography methods, recrystallization methods, washing with a solvent, etc.).

Compound (Ia) can be produced according to the production method of compound (I).
The metal complex of compound (I) can be produced according to a known method, for example, the method described in International Publication No. 02/050190 pamphlet or the like. Specifically, the organometallic compound or metal salt and the compound (I) are optionally added at 25 to 120 ° C. in a solvent in the presence of 1 to 5 moles of acetic acid with respect to the organometallic compound or metal salt. The metal complex of compound (I) can be produced by reacting at a temperature of 0.1 to 30 hours.
The amount of compound (I) used is preferably 0.5 to 5 times the molar amount of the organometallic compound or metal salt.

Examples of the organometallic compound include aluminum tris (acetylacetonate), aluminum tris (ethylacetoacetate), aluminum isopropoxide, aluminum sec-butoxide, aluminum ethoxide, copper acetylacetonate, zinc acetylacetonate, iron tris. (2,4-pentanedionate), tris (carbonate) cobalt (III) sodium salt, and the like.
Examples of the metal salt include aluminum chloride, copper chloride, copper acetate, nickel acetate, nickel chloride, cobalt acetate, cobalt chloride, and hydrates thereof.

Examples of the solvent include alcohol solvents such as methanol, ethanol, propanol, 2-propanol, butanol and isobutanol, halogen solvents such as chloroform and dichloromethane, aromatic solvents such as benzene, toluene and xylene, tetrahydrofuran and methyl. Examples include ether solvents such as -tert-butyl ether, ester solvents such as ethyl acetate, ketone solvents such as acetone and methyl ethyl ketone, and mixed solvents thereof.

After the reaction, if necessary, the metal complex of compound (I) may be purified by methods usually used in organic synthetic chemistry (various column chromatography methods, recrystallization methods, washing with a solvent, etc.).
The metal complex of compound (Ia) can be manufactured according to the manufacturing method of the metal complex of compound (I).

Hereinafter, specific examples of Compound (I) and Compound (Ia) are exemplified. In the table, Me represents a methyl group, Et represents an ethyl group, n-Pr represents a propyl group, i-Pr represents an isopropyl group, n-Bu represents a butyl group, and i-Bu represents an isobutyl group. T-Bu represents a tert-butyl group, and Ph represents a phenyl group.

Hereinafter, the squarylium compound of Compound No. (1) is referred to as Compound (1). The same applies to the compounds with other compound numbers.
The metal complex of the compound (I) used in the present invention is a dye for optical recording media, an ultraviolet absorber, a two-photon absorption dye as a three-dimensional recording material, and an increase in response to short wavelength laser (for example, blue-violet laser). It can be used as a dye-sensitive dye. The metal complex of compound (I) is suitable as a dye for an optical recording medium because it has excellent light resistance, excellent weather resistance, excellent moisture and heat resistance, excellent coating properties, and excellent solubility.

The optical recording medium of the present invention contains a metal complex of compound (I) and has high sensitivity photoresponsiveness to blue-violet laser light, excellent recording signal quality, and the like.
Examples of the optical recording medium of the present invention include a substrate, a reflective layer, a recording layer, a transparent protective layer and a cover layer. The reflective layer, the recording layer, the transparent protective layer and the cover are provided on the substrate. It is preferable that the layers are provided in this order. Examples of the optical recording medium of the present invention include those having a recording layer containing a metal complex of compound (I). When the recording layer is formed using the metal complex of compound (I), the metal complex of compound (I) may be used alone or in admixture of two or more.

The metal complex of compound (I) and other dyes may be used in combination. Other dyes preferably have absorption in the wavelength region of the recording laser light. In addition, a dye that does not hinder the formation of information recording (recording marks, etc. formed at a laser irradiation site due to thermal deformation in the recording layer, the reflective layer or the transparent protective layer, and the cover layer) may be used as another dye. preferable. Examples of other dyes include metal-containing azo dyes, phthalocyanine dyes, naphthalocyanine dyes, cyanine dyes, azo dyes, squarylium dyes other than the metal complex of compound (I), metal-containing indoaniline dyes , Triarylmethane dyes, merocyanine dyes, azurenium dyes, naphthoquinone dyes, anthraquinone dyes, indophenol dyes, xanthene dyes, oxazine dyes, pyrylium dyes, and the like. You may use these individually or in mixture of 2 or more types. Among other dyes, a combination of a dye suitable for recording using a laser beam such as a near infrared laser beam of 770 to 830 nm and a red laser beam of 620 to 690 nm and a metal complex of compound (I) can be used at a plurality of wavelengths. An optical recording medium capable of recording with a laser beam in the region can also be produced.

The recording layer may contain a binder as necessary. Examples of the binder include polyvinyl alcohol, polyvinyl pyrrolidone, ketone resin, nitrocellulose, cellulose acetate, polyvinyl butyral, and polycarbonate. You may use these individually or in mixture of 2 or more types.
Further, the recording layer may contain, for example, a singlet oxygen quencher, a recording sensitivity improver, etc. in order to improve the stability and light resistance of the recording layer.

Examples of the singlet oxygen quencher include transition metal chelate compounds (for example, chelate compounds of acetylacetonate, bisphenyldithiol, salicylaldehyde oxime, bisdithio-α-diketone, etc. and transition metal) and the like. You may use these individually or in mixture of 2 or more types.

As the recording sensitivity improver, a compound in which a metal such as a transition metal is contained in a compound in the form of atoms, ions, clusters, etc., for example, an ethylenediamine complex, an azomethine complex, a phenylhydroxyamine complex, a phenanthroline complex, And organic metal compounds such as dihydroxyazobenzene complex, dioxime complex, nitrosoaminophenol complex, pyridyltriazine complex, acetylacetonate complex, metallocene complex and porphyrin complex. You may use these individually or in mixture of 2 or more types.

The thickness of the recording layer of the optical recording medium of the present invention is preferably 1 nm to 5 μm, more preferably 5 to 100 nm, and further preferably 20 to 60 nm.

The recording layer can be formed by a known thin film forming method such as a vacuum deposition method, a sputtering method, a doctor blade method, a cast method, a spin coating method, or an immersion method, but the spin coating method is preferable from the viewpoint of mass productivity and cost. . When the recording layer is formed by the spin coating method, in order to obtain an appropriate film thickness, a solution in which the concentration of the metal complex of compound (I) is adjusted to 0.3 to 1.5% by weight is used, and the rotation speed is 500. It is preferable to set it to ˜10000 rpm. After applying the solution by a spin coating method, treatment such as heating, drying under reduced pressure, or exposure to solvent vapor may be performed.

When a recording layer is formed by applying a solution (for example, a doctor blade method, a cast method, a spin coating method, a dipping method, etc.), the solvent of the solution may be on the substrate before applying the substrate and the recording layer. The solvent is not particularly limited as long as it is a solvent that does not attack the formed layer (for example, a reflective layer). For example, ketone alcohol solvents such as diacetone alcohol and 3-hydroxy-3-methyl-2-butanone, cellosolv solvents such as methyl cellosolve and ethyl cellosolve, n-hexane, n-octane, cyclohexane, methylcyclohexane, ethylcyclohexane Hydrocarbon solvents such as dimethylcyclohexane, n-butylcyclohexane, tert-butylcyclohexane and cyclooctane, ether solvents such as diisopropyl ether and dibutyl ether, and fluoroalkyl such as tetrafluoropropanol, octafluoropentanol and hexafluorobutanol Examples include alcohol solvents, ester solvents such as methyl lactate, ethyl lactate, and methyl isobutyrate. You may use these individually or in mixture of 2 or more types.

The substrate of the optical recording medium of the present invention is preferably such that a guide groove formed in a spiral shape is formed on the surface for recording / reproduction with a laser beam. As the substrate, those that can easily form fine grooves having a narrow track pitch are preferable, and specific examples thereof include glass and plastic. Examples of plastics include acrylic resin, methacrylic resin, polycarbonate resin, vinyl chloride resin, vinyl acetate resin, nitrocellulose, polyester resin, polyethylene resin, polypropylene resin, polyimide resin, polystyrene resin, epoxy resin, and alicyclic polyolefin resin. However, a polycarbonate resin is preferable from the viewpoint of high productivity, cost, moisture absorption resistance, and the like.

The substrate is preferably produced by injection molding the plastic. Examples of a method for producing a substrate by injection molding include a method using a stamper made of a metal such as Ni in which a guide groove is formed.
The master for producing the stamper is produced, for example, as follows. Polish the surface of the disk-shaped glass substrate to be smooth. A photoresist whose thickness is adjusted according to a desired groove depth is applied on the substrate. Next, the photoresist is exposed using a laser beam or an electron beam having a wavelength shorter than that of the blue-violet laser beam and developed, thereby producing a master having a guide groove.

Next, a conductive film such as Ni is vacuum-deposited on the surface of the master, and a stamper made of a metal such as Ni in which a guide groove is formed is produced through a plating process. A substrate having guide grooves formed on the surface is produced by injection molding the plastic using this stamper.

The guide groove preferably has a height difference (groove depth) between the top surface and the bottom surface of the unevenness of 15 to 80 nm, and more preferably 25 to 50 nm. The ratio of the width of the convex part to the concave part is preferably in the range of 40%: 60% to 60%: 40% (convex part: concave part).

The reflective layer is preferably a metal. Examples of the metal include gold, silver, aluminum, and alloys thereof. From the viewpoint of reflectivity with respect to laser light having a wavelength of 550 nm or less and surface smoothness, an alloy mainly composed of silver or silver is used. preferable. The silver-based alloy preferably contains about 90% or more of silver, and is selected from the group of Cu, Pd, Ni, Si, Au, Al, Ti, Zn, Zr, Nb, and Mo as components other than silver. Those containing at least one selected from the above are preferred. The reflective layer can be formed on the substrate by, for example, vapor deposition, sputtering (eg, DC sputtering), ion plating, or the like. An intermediate layer may be provided between the reflective layer and the recording layer for the purpose of improving the recording / reproducing characteristics or adjusting the reflectance. Examples of the material for the intermediate layer include metals, metal oxides, metal nitrides, and the like. The thickness of the reflective layer is preferably 5 to 300 nm, and more preferably 30 to 100 nm.

The transparent protective layer preferably has no or little absorption with respect to the laser beam used during recording and reproduction, and the real part of the refractive index is relatively large, about 1.5 to 2.0. What has the value of is preferable. Examples of the material for the transparent protective layer include metal oxides, metal nitrides, metal sulfides, and mixtures thereof.

The thickness of the transparent protective layer is preferably 5 to 50 nm. When the thickness of the protective layer is 5 nm or more, a recording signal formed by deforming the recording layer can be clearly separated from an unrecorded portion between the recording marks, so that a better signal can be obtained. Further, when the thickness of the protective layer is 50 nm or less, the transparent protective layer is easily deformed, so that a better signal can be obtained. The transparent protective layer can be formed on the recording layer by sputtering (for example, RF sputtering).

For the cover layer, for example, a polycarbonate sheet having a thickness of about 0.1 mm having an adhesive layer that is transparent to the recording / reproducing laser beam on the surface is used, and the sheet is transparently protected via the adhesive layer. By pressure-bonding to the layer, it can be formed on the transparent protective layer. The adhesive layer is preferably one that does not hinder the deformation of the recording layer and the transparent protective layer during information recording. The cover layer can also be formed using an ultraviolet curable resin, and the ultraviolet curable resin is preferably one that does not hinder the deformation of the recording layer and the transparent protective layer during information recording, like the adhesive layer.

Since the optical recording medium of the present invention contains the metal complex of compound (I), the wavelength of the laser beam used for recording is preferably 350 to 530 nm. In general, the shorter the wavelength of laser light used for recording, the higher the density recording possible.

Specific examples of laser light include, for example, blue-violet laser light having a center wavelength of 405 nm, 410 nm, etc., blue-green high-power semiconductor laser light having a center wavelength of 515 nm, and the center wavelength is 405 nm. Blue-green high-power semiconductor laser light is preferred.
A semiconductor laser beam capable of continuous oscillation having a fundamental oscillation wavelength of 740 to 960 nm, a solid-state laser beam excited by the semiconductor laser beam and capable of continuous oscillation having a fundamental oscillation wavelength of 740 to 960 nm, etc. Light obtained by wavelength conversion by SHG) may be used. SHG may be any piezo element that lacks reflection symmetry, but KDP (KH ₂ PO ₄ ), ADP (NH ₄ H ₂ PO ₄ ), BNN (Ba ₂ NaNb ₅ O ₁₅ ), KN ( Preferred examples of SHG include KNbO ₃ ), LBO (LiB ₃ O ₅ ), and compound semiconductors.

Specific examples of light (second harmonic) obtained by wavelength conversion by SHG include, for example, 430 nm light obtained by wavelength conversion of semiconductor laser light having a fundamental oscillation wavelength of 860 nm, and semiconductor laser having a fundamental oscillation wavelength of 860 nm. Examples thereof include 430 nm light obtained by wavelength conversion of excitation solid-state laser light.
The optical recording medium of the present invention is preferably a BD. The BD is an optical recording medium that uses a blue-violet laser having a wavelength of 405 nm and records a higher density information by reducing the laser spot diameter by setting the NA of the objective lens to 0.85. In the BD-R, a reflective layer, a recording layer, a transparent protective layer, and a cover layer thinner than the substrate are sequentially laminated on the substrate. Recording and reproduction is performed by irradiating a blue-violet laser beam from the cover layer side.

Hereinafter, the present invention will be described more specifically with reference to examples and reference examples.
Compounds (III-1) to (III-12) used as raw materials for the squarylium compound were produced according to a known method, for example, a method described in International Publication No. 2001/44233 pamphlet or the like. In the formula, Me, n-Pr, i-Pr, t-Bu and Ph have the same meanings as described above.

(Manufacture of squarylium compounds)
[Reference Example 1-1] Compound (2)
3-hydroxy-4- [1- (3-chlorophenyl) -5-hydroxy-3-propylpyrazol-4-yl] cyclobutene-1,2-dione [compound (III-1)] 1060 mg and N-ethyl-4 -0.53 g of chloroaniline was reacted in a mixed solvent of 7 mL of butanol and 15 mL of toluene at 100 to 120 ° C for 7.0 hours. Toluene in the reaction solution was distilled off, 6 mL of methanol was added to the residue, and the precipitated solid was collected by filtration to obtain 1.30 g (yield 86%) of Compound (2).
¹ H-NMR (400 MHz) δ (CDCl ₃ ) ppm: 0.95-1.06 (3H, m), 1.35 (3H, m), 1.73 (2H, m), 2.85 (1H , T), 2.92 (1H, t), 4.33 (1H, dd), 4.46 (1H, dd), 7.22-7.37 (4H, m), 7.46-7. 48 (2H, m), 7.76 (1H, dd), 7.87 (1H, d).
Absorption maximum wavelength (CHCl ₃ ): 430.5 nm
Molar extinction coefficient (CHCl ₃ ): 56300 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 1-2] Compound (4)
Instead of compound (III-1) and N-ethyl-4-chloroaniline, 3-hydroxy-4- (5-hydroxy-1-phenyl-3-propylpyrazol-4-yl) cyclobutene-1,2-dione [ The same operation as in Reference Example 1-1 was carried out except that compound (III-2)] and morpholine were used to obtain compound (4) (yield 81%).
¹ H-NMR (400 MHz) δ (CDCl ₃ ) ppm: 1.02 (9H, t), 1.74 (2H, m), 2.88 (2H, m), 3.89 (4H, t), 4.00 (2H, bs), 4.12 (2H, bs), 7.26-7.30 (1H, m), 7.41-7.46 (2H, m), 7.78-7. 82 (2H, m), 14.3 (1 H, bs).
Absorption maximum wavelength (CHCl ₃ ): 412.5 nm
Molar extinction coefficient (CHCl ₃ ): 64100 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 1-3] Compound (7)
Instead of compound (III-1) and N-ethyl-4-chloroaniline, 3-hydroxy-4- (5-hydroxy-3-phenyl-1-tert-butylpyrazol-4-yl) cyclobutene-1,2- The same operation as in Reference Example 1-1 was carried out except that dione [compound (III-3)] and N-methyl-2-fluoroaniline were used to obtain compound (7) (yield 67%).
¹ H-NMR (400 MHz) δ (CDCl ₃ ) ppm: 1.61 (9H, s), 3.86 (3H, s), 7.10-7.50 (7H, bm), 7.63 (2H , Bs), 14.7 (1H, bs).
Absorption maximum wavelength (CHCl ₃ ): 427.0 nm
Molar extinction coefficient (CHCl ₃ ): 47700 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 1-4] Compound (17)
3.67 g of 3-hydroxy-4- [1- (4-chlorophenyl) -5-hydroxy-3-phenylpyrazol-4-yl] cyclobutene-1,2-dione [compound (III-4)] and 0. 96 g was reacted at 130 ° C. for 4 hours in a mixed solvent of 10 mL of n-butanol and 5 mL of toluene. After cooling the reaction solution, 10 mL of methanol was added to the reaction solution, and the precipitated solid was collected by filtration and washed with methanol to obtain 4.17 g (yield 96%) of Compound (17).
¹ H-NMR (400 MHz) δ (CDCl ₃ ) ppm: 3.85-3.87 (4H, m), 4.04 (4H, s), 7.39-7.45 (5H, m), 7 .66-7.69 (2H, m), 7.87-7.89 (2H, m).
Absorption maximum wavelength (CHCl ₃ ): 415.5 nm
Molar extinction coefficient (CHCl ₃ ): 43600 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 1-5] Compound (24)
3-hydroxy-4- (5-hydroxy-1-methyl-3-trifluoromethylpyrazol-4-yl) cyclobutene-1,2-dione [compound (III-5)] instead of compound (III-4) The compound (24) (yield 67%) was obtained in the same manner as in Reference Example 1-4 except that was used.
¹ H-NMR (400 MHz) δ (CDCl ₃ ) ppm: 1.79 (3H, s), 3.66 (4H, s), 4.06 (6H, s), 14.25 (1H, bs).
Absorption maximum wavelength (CHCl ₃ ): 398.0 nm
Molar extinction coefficient (CHCl ₃ ): 40000 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 1-6] Compound (29)
A compound (29) (yield 79%) was obtained in the same manner as in Reference Example 1-4, except that compound (III-1) was used instead of compound (III-4).
¹ H-NMR (400 MHz) δ (CDCl ₃ ) ppm: 1.02 (3H, t, J = 7.3 Hz), 1.70-1.76 (2H, m), 2.87 (2H, t, J = 7.6 Hz), 3.90-3.93 (4H, m), 4.02 (2H, s), 4.14 (2H, s), 7.23-7.25 (1 H, m) , 7.33-7.37 (1H, m), 7.62-7.77 (1H, m), 7.88-7.89 (1H, m).
Absorption maximum wavelength (CHCl ₃ ): 413.0 nm
Molar extinction coefficient (CHCl ₃ ): 59600 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 1-7] Compound (35)
Instead of compound (III-4) and morpholine, 3-hydroxy-4- [5-hydroxy-3-isopropyl-1- (2-pyridyl) pyrazol-4-yl] cyclobutene-1,2-dione [compound (III −6)] and bis (2-ethoxyethyl) amine were used in the same manner as in Reference Example 1-4 to obtain compound (35) (yield 62%).
¹ H-NMR (400 MHz) δ (CDCl ₃ ) ppm: 1.19 (6H, t, J = 7.0 Hz), 1.34-1.36 (7H, m), 3.50-3.56 ( 4H, m), 3.71-3.73 (4H, m), 4.12-4.15 (4H, m), 7.19-7.22 (1H, m), 7.57 (1H, d, J = 5.1 Hz), 7.80-7.82 (2H, m).
Absorption maximum wavelength (CHCl ₃ ): 412.5 nm
Molar extinction coefficient (CHCl ₃ ): 39600 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 1-8] Compound (39)
Instead of compound (III-4), 3-hydroxy-4- [1- (2-benzothiazolyl) -5-hydroxy-3-tert-butylpyrazol-4-yl] cyclobutene-1,2-dione [compound (III −7)] was used in the same manner as in Reference Example 1-4 to obtain compound (39) (yield 81%).
¹ H-NMR (400 MHz) δ (CDCl ₃ ) ppm: 1.48 (9H, s), 3.89-3.92 (4H, m), 4.06-4.09 (4H, m), 7 .29-7.32 (1H, m), 7.41-7.45 (1H, m), 7.76 (1H, d, J = 7.1 Hz), 7.92 (1H, bs).
Absorption maximum wavelength (CHCl ₃ ): 422.5 nm
Molar extinction coefficient (CHCl ₃ ): 51100 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 1-9] Compound (44)
Instead of compound (III-4), 3-hydroxy-4- [5-hydroxy-1- (2-hydroxyethyl) -3-methylpyrazol-4-yl] cyclobutene-1,2-dione [compound (III- 8)] was used in the same manner as in Reference Example 1-4 to obtain compound (44) (yield 79%).
¹ H-NMR (400 MHz) δ (CDCl ₃ ) ppm: 2.40 (3H, s), 3.90-3.98 (12H, m).
Absorption maximum wavelength (CHCl ₃ ): 416.0 nm
Molar extinction coefficient (CHCl ₃ ): 37400 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 1-10] Compound (48)
0.75 g of 3-hydroxy-4- [5-hydroxy-3- (3-nitrophenyl) -1-phenylpyrazol-4-yl] cyclobutene-1,2-dione [compound (III-9)] and N- 0.41 g of (2-tert-butoxyethyl) cyclopentylamine was reacted at 130 ° C. for 28 hours in the presence of 0.03 g of sulfuric acid in a mixed solvent of 8 mL of n-butanol and 4 mL of toluene. The solvent in the reaction solution was distilled off, 2 mL of 2-propanol was added to the residue, and the precipitated solid was collected by filtration and washed with methanol to obtain 0.84 g of Compound (48) (yield 77%). .
¹ H-NMR (400 MHz) δ (CDCl ₃ ) ppm: 1.18 (9H, s), 1.65 (2H, bs), 1.85 (4H, bs), 2.05 (2H, bs), 3.68 (4H, bs), 3.88 (4H, bs), 7.31-7.35 (1H, m), 7.46-7.50 (2H, m), 7.59-7. 62 (1H, m), 7.86-7.91 (1H, m), 8.05-8.07 (1H, m), 8.64 (1H, s).
Absorption maximum wavelength (CHCl ₃ ): 404.5 nm
Molar extinction coefficient (CHCl ₃ ): 84200 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 1-11] Compound (49)
1500 mg of 3-hydroxy-4- (5-hydroxy-1-tert-butyl-3-trifluoromethylpyrazol-4-yl) cyclobutene-1,2-dione [compound (III-10)] and 2-hydrazinopyridine 0.59 g was reacted in 10 mL of acetonitrile at 70 ° C. for 2 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with acetonitrile to obtain 1.50 g (yield 77%) of Compound (49).
¹ H-NMR (400 MHz) δ (DMSO-d ₆ ) ppm: 1.54 (9H, s), 6.95 (1H, t, J = 6.1 Hz), 7.41 (1H, d, J = 9.0 Hz), 7.91-7.99 (2H, m), 11.68 (1H, bs).
Absorption maximum wavelength (CHCl ₃ ): 411.0 nm
Molar extinction coefficient (CHCl ₃ ): 30500 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 1-12] Compound (54)
The same operation as in Reference Example 1-11 was carried out, except that 2-hydrazino-4,6-dimethoxypyrimidine was used instead of 2-hydrazinopyridine, to obtain compound (54) (yield 87%).
¹ H-NMR (400 MHz) δ (DMSO-d ₆ ) ppm: 1.54 (9H, s), 3.86 (6H, s), 5.67 (1H, s), 10.07 (1H, bs) ).
Absorption maximum wavelength (CHCl ₃ ): 394.0 nm
Molar extinction coefficient (CHCl ₃ ): 36100 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 1-13] Compound (61)
The same operation as in Reference Example 1-11 was carried out, except that compound (III-5) was used in place of compound (III-10) to obtain compound (61) (yield 74%).
¹ H-NMR (400 MHz) δ (DMSO-d ₆ ) ppm: 3.56 (3H, s), 6.95 (1H, t, J = 6.6 Hz), 7.40 (1H, d, J = 9.0 Hz), 7.91-7.98 (2H, m), 11.65 (1H, bs), 13.53 (1H, bs).
Absorption maximum wavelength (CHCl ₃ ): 406.5 nm
Molar extinction coefficient (CHCl ₃ ): 28000 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 1-14] Compound (63)
The same procedure as in Reference Example 1-11 was carried out, except that compound (III-5) and 2-hydrazino-4,6-dimethoxypyrimidine were used instead of compound (III-10) and 2-hydrazinopyridine. 63) (yield 87%).
¹ H-NMR (400 MHz) δ (DMSO-d ₆ ) ppm: 3.56 (3H, s), 3.86 (6H, s), 5.70 (1H, s), 10.11 (1H, bs ).
Absorption maximum wavelength (CHCl ₃ ): 380.5 nm
Molar extinction coefficient (CHCl ₃ ): 39900 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 1-15] Compound (71)
The same operation as in Reference Example 1-11 was conducted, except that compound (III-5) and 2-hydrazinopyrimidine were used instead of compound (III-10) and 2-hydrazinopyridine, to give compound (71) (yield) 88%).
¹ H-NMR (400 MHz) δ (DMSO-d ₆ ) ppm: 3.56 (3H, s), 7.02 (1H, t, J = 5.1 Hz), 8.59 (2H, m), 11 .38 (1H, bs).

[Reference Example 1-16] Compound (77)
Instead of compound (III-10) and 2-hydrazinopyridine, 3-hydroxy-4- [5-hydroxy-1- (4-methoxyphenyl) -3-phenylpyrazol-4-yl] cyclobutene-1,2- The same operation as in Reference Example 1-11 was carried out, except that dione [compound (III-11)] and 2-hydrazinopyrimidine were used, to obtain compound (77) (yield 88%).
¹ H-NMR (400 MHz) δ (DMSO-d ₆ ) ppm: 3.80 (3H, s), 6.98-7.06 (3H, m), 7.36-7.38 (3H, m) , 7.70-7.72 (4H, m), 8.58 (2H, m), 11.39 (1H, bs).
Absorption maximum wavelength (CHCl ₃ ): 385.0.0 nm
Molar extinction coefficient (CHCl ₃ ): 26400 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 1-17] Compound (84)
Instead of compound (III-10), 3-hydroxy-4- (5-hydroxy-1-phenyl-3-trifluoromethylpyrazol-4-yl) cyclobutene-1,2-dione [compound (III-12)] The compound (84) (yield 61%) was obtained in the same manner as in Reference Example 1-11 except that was used.
¹ H-NMR (400 MHz) δ (DMSO-d ₆ ) ppm: 6.97 (1H, t, J = 6.4 Hz), 7.39-7.42 (2H, m), 7.52 (2H, t, J = 7.6 Hz), 7.76 (2H, d, J = 7.6 Hz), 7.93-7.98 (2H, m), 11.68 (1H, bs).
Absorption maximum wavelength (CHCl ₃ ): 407.5 nm
Molar extinction coefficient (CHCl ₃ ): 27900 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 1-18] Compound (93)
The same procedure as in Reference Example 1-11 was carried out, except that compound (III-12) and 2-hydrazino-4,6-dimethoxypyrimidine were used instead of compound (III-10) and 2-hydrazinopyridine. 93) (yield 86%).
¹ H-NMR (400 MHz) δ (DMSO-d ₆ ) ppm: 3.85 (3H, s), 5.62 (1H, s), 7.37 (1H, t, J = 7.6 Hz), 7 .51 (2H, t, J = 7.6 Hz), 7.76 (1H, d, J = 9.6 Hz), 9.82 (1H, bs).
Absorption maximum wavelength (CHCl ₃ ): 393.0 nm
Molar extinction coefficient (CHCl ₃ ): 42100 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 1-19] Compound (102)
The same procedure as in Reference Example 1-11 was carried out, except that compound (III-12) and 2-hydrazino-3-trifluoromethylpyridine were used instead of compound (III-10) and 2-hydrazinopyridine. 102) (yield 83%).
¹ H-NMR (400 MHz) δ (DMSO-d ₆ ) ppm: 7.12 (1H, t, J = 6.6 Hz), 7.40 (1H, t, J = 7.6 Hz), 7.53 ( 2H, t, J = 7.6 Hz), 7.75 (2H, d, J = 7.6 Hz), 8.27 (1H, d, J = 5.6 Hz), 8.43 (1H, d, J = 7.6 Hz), 10.99 (1H, bs).
Absorption maximum wavelength (CHCl ₃ ): 415.5 nm
Molar extinction coefficient (CHCl ₃ ): 23700 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 1-20] Compound (107)
The same operation as in Reference Example 1-11 was carried out, except that compound (III-12) and 2-hydrazinopyrimidine were used instead of compound (III-10) and 2-hydrazinopyridine, to give compound (107) (yield) 92%).
¹ H-NMR (400 MHz) δ (DMSO-d ₆ ) ppm: 7.05 (1H, t, J = 5.1 Hz), 7.39 (1H, t, J = 7.6 Hz), 7.52 ( 2H, t, J = 7.6 Hz), 7.76 (2H, d, J = 7.8 Hz), 8.62 (2H, m), 11.52 (1H, bs).
Absorption maximum wavelength (CHCl ₃ ): 370.5 nm
Molar extinction coefficient (CHCl ₃ ): 20700 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 1-21] Compound (112)
The same operation as in Reference Example 1-11 was carried out except that 2-hydrazino-3-trifluoromethylpyridine was used in place of 2-hydrazinopyridine to give compound (112) (yield 98%).
¹ H-NMR (400 MHz) δ (DMSO-d ₆ ) ppm: 1.53 (9H, s), 7.09 (1H, t, J = 7.1 Hz), 8.24 (1H, d, J = 5.9 Hz), 8.40 (1H, d, J = 7.8 Hz).
Absorption maximum wavelength (CHCl ₃ ): 379.0 nm
Molar extinction coefficient (CHCl ₃ ): 18500 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 1-22] Compound (115)
The same procedure as in Reference Example 1-11 was carried out, except that compound (III-5) and 2-hydrazino-3-trifluoromethylpyridine were used instead of compound (III-10) and 2-hydrazinopyridine. 115) (yield 77%).
¹ H-NMR (400 MHz) δ (DMSO-d ₆ ) ppm: 3.57 (3H, s), 7.10 (1H, t, J = 6.8 Hz), 8.25 (1H, d, J = 5.6 Hz), 8.42 (1H, d, J = 7.3 Hz), 11.00 (1H, bs).
Absorption maximum wavelength (CHCl ₃ ): 378.5 nm
Molar extinction coefficient (CHCl ₃ ): 19900 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 1-23] Compound (120)
1.50 g of the potassium salt of compound (III-5) and 0.81 g of 1-hydrazinophthalazine hydrochloride were reacted in 70 mL of ethanol at 70 ° C. for 3 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 1.95 g (yield 100%) of Compound (120).
¹ H-NMR (400 MHz) δ (DMSO-d ₆ ) ppm: 7.39 (1H, t, J = 6.8 Hz), 7.54 (1H, t, J = 6.8 Hz), 7.66 ( 1H, d, J = 6.8 Hz), 8.13-8.21 (3H, m), 8.44-8.46 (1H, m), 8.94 (1H, s), 14.38 ( 1H, bs).
Absorption maximum wavelength (CHCl ₃ ): 425.0 nm
Molar extinction coefficient (CHCl ₃ ): 31900 (mol / L) ⁻¹ · cm ⁻¹
(Production of metal complexes of squarylium compounds)

[Reference Example 2-1] 3: 1 Complex of Compound (2) and Iron [Compound (2-F)]
522 mg of compound (2) and 113 mg of iron tris (2,4-pentandionate) were reacted in ethanol at 70 to 80 ° C. for 3.5 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 460 mg (yield 85%) of compound (2-F).
Absorption maximum wavelength (CHCl ₃ ): 430.0 nm
Molar extinction coefficient (CHCl ₃ ): 108000 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 2-2] 2: 1 Complex of Compound (4) and Cobalt [Compound (4-CO)]
0.51 g of compound (4) and 0.18 g of cobalt (II) acetate tetrahydrate were reacted in 70 mL of ethanol at 70 to 80 ° C. for 3.5 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.52 g (yield 94%) of compound (4-CO).
Absorption maximum wavelength (CHCl ₃ ): 413.0 nm
Molar extinction coefficient (CHCl ₃ ): 143000 (mol / L) ⁻¹ · cm ⁻¹
Molecular weight: 791 [FAB-MS: m / z 792 (M + H) ⁺ ]

[Reference Example 2-3] 3: 1 Complex of Compound (7) and Aluminum [Compound (7-A)]
0.89 g of compound (7) and 0.29 g of aluminum tris (ethylacetoacetate) were reacted in 70 mL of ethanol at 70 to 80 ° C. for 3.5 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.78 g of Compound (7-A) (yield 87%).
Absorption maximum wavelength (CHCl ₃ ): 421.0 nm
Molar extinction coefficient (CHCl ₃ ): 108000 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 2-4] 3: 1 Complex of Compound (17) and Aluminum [Compound (17-A)]
0.92 g of compound (17) and 0.29 g of aluminum tris (ethylacetoacetate) were reacted in 4.8 mL of ethanol at 70 ° C. for 7 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.92 mg of Compound (17-A) (yield 88%).
Absorption maximum wavelength (CHCl ₃ ): 406.5 nm
Molar extinction coefficient (CHCl ₃ ): 128000 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 2-5] 2: 1 Complex of Compound (17) and Cobalt [Compound (17-CO)]
0.70 g of the compound (17) and 0.20 g of cobalt (II) acetate tetrahydrate were reacted in 4.8 mL of ethanol at 70 ° C. for 7 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.72 g (yield 97%) of compound (17-CO).
Absorption maximum wavelength (CHCl ₃ ): 413.5 nm
Molar extinction coefficient (CHCl ₃ ): 65000 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 2-6] 2: 1 Complex of Compound (24) and Cobalt [Compound (24-CO)]
Compound (24) (0.53 g) and cobalt (II) acetate tetrahydrate (0.20 g) were reacted in ethanol (5.3 mL) at 70 ° C. for 4 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.52 g (yield 91%) of compound (24-CO).
Absorption maximum wavelength (CHCl ₃ ): 398.0 nm
Molar extinction coefficient (CHCl ₃ ): 50600 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 2-7] 2: 1 Complex of Compound (29) and Nickel [Compound (29-N)]
0.64 g of compound (29) and 0.20 g of nickel (II) acetate tetrahydrate were reacted in 4.8 mL of ethanol at 70 ° C. for 7 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.66 g (yield 96%) of compound (29-N).
Absorption maximum wavelength (CHCl ₃ ): 413.0 nm
Molar extinction coefficient (CHCl ₃ ): 76900 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 2-8] 2: 1 Complex of Compound (35) and Copper [Compound (35-CU)]
0.62 g of compound (35) and 0.14 g of copper (II) acetate monohydrate were reacted in 12.4 mL of ethanol at 70 ° C. for 4 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.66 g (yield 100%) of compound (35-CU).
Absorption maximum wavelength (CHCl ₃ ): 422.0 nm
Molar extinction coefficient (CHCl ₃ ): 86800 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 2-9] 2: 1 Complex of Compound (39) and Cobalt [Compound (39-CO)]
0.53 g of compound (39) and 0.20 g of cobalt (II) acetate tetrahydrate were reacted in 5.3 mL of ethanol at 70 ° C. for 4 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.52 g (yield 91%) of compound (39-CO).
Absorption maximum wavelength (CHCl ₃ ): 429.0 nm
Molar extinction coefficient (CHCl ₃ ): 75600 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 2-10] 2: 1 Complex of Compound (44) and Cobalt [Compound (44-CO)]
0.53 g of compound (44) and 0.14 g of tris (carbonate) cobalt (III) sodium salt were reacted in 3.7 mL of ethanol at 70 ° C. for 3 hours in the presence of 0.024 g of acetic acid. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.39 g (yield 100%) of compound (44-CO).
Absorption maximum wavelength (CHCl ₃ ): 404.5 nm
Molar extinction coefficient (CHCl ₃ ): 74900 (mol / L) ⁻¹ · cm ⁻¹

[Reference Example 2-11] 2: 1 Complex of Compound (48) and Nickel [Compound (48-N)]
0.33 g of compound (48) and 0.07 g of nickel acetate (II) tetrahydrate were reacted in 3.3 mL of ethanol at 70 ° C. for 3 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.34 g (yield 99%) of compound (48-N).
Absorption maximum wavelength (CHCl ₃ ): 417.0 nm
Molar extinction coefficient (CHCl ₃ ): 65600 (mol / L) ⁻¹ · cm ⁻¹

Example 1 2: 1 Complex of Compound (49) and Nickel [Compound (49-N)]
0.50 g of compound (49) and 0.16 g of nickel (II) acetate tetrahydrate were reacted in 5 mL of ethanol at 70 ° C. for 2 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.52 g (yield 97%) of compound (49-N).
Absorption maximum wavelength (CHCl ₃ ): 415.5 nm
Molar extinction coefficient (CHCl ₃ ): 97900 (mol / L) ⁻¹ · cm ⁻¹

Example 2 2: 1 Complex of Compound (49) and Cobalt [Compound (49-CO)]
0.50 g of compound (49) and 0.16 g of cobalt (II) acetate tetrahydrate were reacted in 5 mL of ethanol at 70 ° C. for 2 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.52 g (yield 97%) of compound (49-CO).
Absorption maximum wavelength (CHCl ₃ ): 407.0 nm
Molar extinction coefficient (CHCl ₃ ): 82500 (mol / L) ⁻¹ · cm ⁻¹
Molecular weight: 847 [FAB-MS: m / z 848 (M + H) ⁺ ]

Example 3 3: 1 Complex of Compound (49) and Aluminum [Compound (49-A)]
0.30 g of compound (49) and 0.093 g of aluminum tris (ethylacetoacetate) were reacted in 3 mL of ethanol at 70 ° C. for 3 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.24 g (yield 79%) of compound (49-A).
Absorption maximum wavelength (2,2,3,3-tetrafluoropropanol): 398.0 nm

Example 4 2: 1 Complex of Compound (54) and Nickel [Compound (54-N)]
0.20 g of compound (54) and 0.06 g of nickel (II) acetate tetrahydrate were reacted in 70 mL of ethanol in 5 mL of ethanol for 2 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.18 g (yield 86%) of compound (54-N).
Absorption maximum wavelength (CHCl ₃ ): 415.5 nm
Molar extinction coefficient (CHCl ₃ ): 97900 (mol / L) ⁻¹ · cm ⁻¹

Example 5 2: 1 Complex of Compound (54) and Cobalt [Compound (54-CO)]
0.20 g of compound (54) and 0.06 g of cobalt (II) acetate tetrahydrate were reacted in 70 mL of ethanol in 5 mL of ethanol for 2 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.14 g (yield 64%) of compound (54-CO).
Absorption maximum wavelength (CHCl ₃ ): 395.0 nm
Molar extinction coefficient (CHCl ₃ ): 88200 (mol / L) ⁻¹ · cm ⁻¹

Example 6 2: 1 Complex of Compound (61) and Nickel [Compound (61-N)]
0.30 g of compound (61) and 0.11 g of nickel (II) acetate tetrahydrate were reacted in 5 mL of ethanol at 70 ° C. for 2 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.35 g (yield 95%) of compound (61-N).
Absorption maximum wavelength (CHCl ₃ ): 412.0 nm
Molar extinction coefficient (CHCl ₃ ): 75200 (mol / L) ⁻¹ · cm ⁻¹
Molecular weight: 762 [FAB-MS: m / z 763 (M + H) ⁺ ]

Example 7 2: 1 Complex of Compound (61) and Cobalt [Compound (61-CO)]
0.30 g of compound (61) and 0.11 g of cobalt (II) acetate tetrahydrate were reacted in 5 mL of ethanol at 70 ° C. for 2 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.35 g of compound (61-CO) (yield 97%).
Absorption maximum wavelength (CHCl ₃ ): 404.0 nm
Molar extinction coefficient (CHCl ₃ ): 92400 (mol / L) ⁻¹ · cm ⁻¹

Example 8 2: 1 Complex of Compound (63) and Nickel [Compound (63-N)]
0.50 g of compound (63) and 0.15 g of nickel (II) acetate tetrahydrate were reacted in 70 mL of ethanol in 5 mL of ethanol for 2 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.48 g (yield 90%) of compound (63-N).
Absorption maximum wavelength (CHCl ₃ ): 396.5 nm
Molar extinction coefficient (CHCl ₃ ): 94500 (mol / L) ⁻¹ · cm ⁻¹
Molecular weight: 885 [FAB-MS: m / z 886 (M + H) ⁺ ]

Example 9 2: 1 Complex of Compound (63) and Cobalt [Compound (63-CO)]
0.50 g of compound (63) and 0.15 g of cobalt (II) acetate tetrahydrate were reacted in 5 mL of ethanol at 70 ° C. for 2 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.47 g (yield 89%) of compound (63-CO).
Absorption maximum wavelength (CHCl ₃ ): 392.5 nm
Molar extinction coefficient (CHCl ₃ ): 84600 (mol / L) ⁻¹ · cm ⁻¹

Example 10 2: 1 Complex of Compound (71) and Nickel [Compound (71-N)]
0.20 g of compound (71) and 0.07 g of nickel (II) acetate tetrahydrate were reacted in 3 mL of ethanol at 70 ° C. for 2 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.21 g (yield 99%) of compound (71-N).
Absorption maximum wavelength (CHCl ₃ ): 410.0 nm
Molar extinction coefficient (CHCl ₃ ): 76400 (mol / L) ⁻¹ · cm ⁻¹

Example 11 2: 1 Complex of Compound (71) and Cobalt [Compound (71-CO)]
0.20 g of compound (71) and 0.07 g of cobalt (II) acetate tetrahydrate were reacted in 3 mL of ethanol at 70 ° C. for 2 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.21 g (yield 96%) of compound (71-CO).
Absorption maximum wavelength (CHCl ₃ ): 401.5 nm
Molar extinction coefficient (CHCl ₃ ): 66300 (mol / L) ⁻¹ · cm ⁻¹

Example 12 2: 1 Complex of Compound (77) and Nickel [Compound (77-N)]
0.20 g of compound (77) and 0.06 g of nickel acetate (II) tetrahydrate were reacted in 70 mL of ethanol in 5 mL of ethanol for 2 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.21 g (yield 100%) of compound (77-N).
Absorption maximum wavelength (CHCl ₃ ): 426.0 nm
Molar extinction coefficient (CHCl ₃ ): 63200 (mol / L) ⁻¹ · cm ⁻¹

Example 13 2: 1 Complex of Compound (77) and Cobalt [Compound (77-CO)]
0.20 g of compound (77) and 0.06 g of cobalt (II) acetate tetrahydrate were reacted in 70 mL of ethanol in 5 mL of ethanol for 2 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.21 g (yield 94%) of compound (77-CO).
Absorption maximum wavelength (CHCl ₃ ): 417.5 nm
Molar extinction coefficient (CHCl ₃ ): 77600 (mol / L) ⁻¹ · cm ⁻¹
Molecular weight: 965 [FAB-MS: m / z 966 (M + H) ⁺ ]

Example 14 3: 1 Complex of Compound (77) and Aluminum [Compound (77-A)]
0.30 g of compound (77) and 0.08 mg of aluminum tris (ethyl acetoacetate) were reacted in 3 mL of ethanol at 70 ° C. for 3 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.30 g (yield 92%) of compound (77-A).
Absorption maximum wavelength (2,2,3,3-tetrafluoropropanol): 354.5 nm

Example 15 2: 1 Complex of Compound (84) and Nickel [Compound (84-N)]
0.30 g of compound (84) and 0.09 g of nickel (II) acetate tetrahydrate were reacted in 70 mL of ethanol in 5 mL of ethanol for 2 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.31 g (yield 100%) of compound (84-N).
Absorption maximum wavelength (CHCl ₃ ): 414.0 nm
Molar extinction coefficient (CHCl ₃ ): 90100 (mol / L) ⁻¹ · cm ⁻¹

[Example 16] 2: 1 complex of compound (84) and cobalt [compound (84-CO)]
0.30 g of the compound (84) and 0.09 g of cobalt (II) acetate tetrahydrate were reacted in 5 mL of ethanol at 70 ° C. for 2 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.31 g (yield 100%) of compound (84-CO).
Absorption maximum wavelength (CHCl ₃ ): 405.0 nm
Molar extinction coefficient (CHCl ₃ ): 76400 (mol / L) ⁻¹ · cm ⁻¹

Example 17 2: 1 Complex of Compound (93) and Nickel [Compound (93-N)]
0.15 g of compound (93) and 0.04 g of nickel (II) acetate tetrahydrate were reacted in 5 mL of ethanol at 70 ° C. for 2 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.13 g (yield 83%) of compound (93-N).
Absorption maximum wavelength (CHCl ₃ ): 399.5 nm
Molar extinction coefficient (CHCl ₃ ): 90300 (mol / L) ⁻¹ · cm ⁻¹
Molecular weight: 1008 [FAB-MS: m / z 1009 (M + H) ⁺ ]

[Example 18] 2: 1 complex of compound (93) and cobalt [compound (93-CO)]
0.30 g of compound (93) and 0.08 g of cobalt (II) acetate tetrahydrate were reacted in 5 mL of ethanol at 70 ° C. for 2 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.31 g (yield 100%) of compound (93-CO).
Absorption maximum wavelength (CHCl ₃ ): 395.5 nm
Molar extinction coefficient (CHCl ₃ ): 90100 (mol / L) ⁻¹ · cm ⁻¹

Example 19 2: 1 Complex of Compound (102) and Nickel [Compound (102-N)]
0.15 g of compound (102) and 0.04 g of nickel (II) acetate tetrahydrate were reacted in 70 mL of ethanol in 5 mL of ethanol for 2 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.16 g (yield 97%) of compound (102-N).
Absorption maximum wavelength (CHCl ₃ ): 419.5 nm
Molar extinction coefficient (CHCl ₃ ): 104800 (mol / L) ⁻¹ · cm ⁻¹

Example 20 2: 1 Complex of Compound (102) and Cobalt [Compound (102-CO)]
0.30 g of compound (102) and 0.08 g of cobalt (II) acetate tetrahydrate were reacted in 70 mL of ethanol in 5 mL of ethanol for 2 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.33 g (yield 100%) of compound (102-CO).
Absorption maximum wavelength (CHCl ₃ ): 412.0 nm
Molar extinction coefficient (CHCl ₃ ): 101500 (mol / L) ⁻¹ · cm ⁻¹

[Example 21] 2: 1 complex of compound (107) and nickel [compound (107-N)]
0.15 g of the compound (107) and 0.05 g of nickel (II) acetate tetrahydrate were reacted in 5 mL of ethanol at 70 ° C. for 2 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.17 g (yield 100%) of compound (107-N).
Absorption maximum wavelength (CHCl ₃ ): 412.5 nm
Molar extinction coefficient (CHCl ₃ ): 90300 (mol / L) ⁻¹ · cm ⁻¹

[Example 22] 2: 1 complex of compound (107) and cobalt [compound (107-CO)]
0.20 g of compound (107) and 0.06 g of cobalt (II) acetate tetrahydrate were reacted in 70 mL of ethanol in 5 mL of ethanol for 2 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.20 g (yield 100%) of compound (107-CO).
Absorption maximum wavelength (CHCl ₃ ): 404.5 nm
Molar extinction coefficient (CHCl ₃ ): 73400 (mol / L) ⁻¹ · cm ⁻¹

[Example 23] 2: 1 complex of compound (112) and nickel [compound (112-N)]
0.20 g of compound (112) and 0.06 g of nickel (II) acetate tetrahydrate were reacted in 70 mL of ethanol in 5 mL of ethanol for 2 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.17 g (yield 79%) of compound (112-N).
Absorption maximum wavelength (CHCl ₃ ): 421.0 nm
Molar extinction coefficient (CHCl ₃ ): 83100 (mol / L) ⁻¹ · cm ⁻¹

[Example 24] 2: 1 complex of compound (112) and cobalt [compound (112-CO)]
0.20 g of compound (112) and 0.06 g of cobalt (II) acetate tetrahydrate were reacted in 70 mL of ethanol in 5 mL of ethanol for 2 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.21 g (yield 98%) of compound (112-CO).
Absorption maximum wavelength (CHCl ₃ ): 412.5 nm
Molar extinction coefficient (CHCl ₃ ): 58700 (mol / L) ⁻¹ · cm ⁻¹

Example 25 2: 1 Complex of Compound (115) and Nickel [Compound (115-N)]
0.25 g of compound (115) and 0.07 g of nickel acetate (II) tetrahydrate were reacted in 70 mL of ethanol in 5 mL of ethanol for 2 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.24 g (yield 89%) of compound (115-N).
Absorption maximum wavelength (CHCl ₃ ): 417.0 nm
Molar extinction coefficient (CHCl ₃ ): 91600 (mol / L) ⁻¹ · cm ⁻¹

[Example 26] 2: 1 complex of compound (115) and cobalt [compound (115-CO)]
0.25 g of compound (115) and 0.07 g of cobalt (II) acetate tetrahydrate were reacted in 70 mL of ethanol in 5 mL of ethanol for 2 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.25 g of compound (115-CO) (yield 92%).
Absorption maximum wavelength (CHCl ₃ ): 409.5 nm
Molar extinction coefficient (CHCl ₃ ): 71500 (mol / L) ⁻¹ · cm ⁻¹

Example 27 2: 1 Complex of Compound (120) and Nickel [Compound (120-N)]
0.20 g of compound (120) and 0.05 g of nickel (II) acetate tetrahydrate were reacted in 2 mL of ethanol at 70 ° C. for 2 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.21 g of Compound (120-N) (yield 100%).
Absorption maximum wavelength (CHCl ₃ ): 423.0 nm
Molar extinction coefficient (CHCl ₃ ): 63300 (mol / L) ⁻¹ · cm ⁻¹

[Example 28] 2: 1 complex of compound (120) and cobalt [compound (120-CO)]
0.20 g of the compound (120) and 0.05 g of cobalt (II) acetate tetrahydrate were reacted in 2 mL of ethanol at 70 ° C. for 2 hours. After cooling the reaction solution, the precipitated solid was collected by filtration and washed with ethanol to obtain 0.15 g (yield 73%) of compound (120-CO).
Absorption maximum wavelength (CHCl ₃ ): 417.5 nm

In the following, a specific example of an optical recording medium according to the present invention will be described as a prototype of a disc conforming to the structure of the write-once Blu-ray Disc (BD-R) shown in FIG. It is not limited by the examples.

[Examples 29 to 37]
<Substrate 101>
A polycarbonate resin was injection molded to produce a substrate having a plate thickness of 1.1 mm and a diameter of 12 cm.
On the surface of the substrate, a spiral tracking guide groove was formed by wobbling with an amplitude of 20 nm with a period of about 5 μm as preformat information such as an address signal in accordance with the BD-R disc standard.
The guide groove was found to have a track pitch of 0.32 μm, a groove depth of 42 nm, and a groove width (half-value width at the top and bottom) of 147 nm, as observed and measured with an atomic force microscope.

<Reflective layer 102>
A reflective layer 102 made of an Ag—Pd—Cu alloy (content Ag: 98 wt%, Pd: 1 wt%, Cu: 1 wt%) was formed on the substrate 101 by DC sputtering. The film thickness of the reflective layer was 45 nm from cross-sectional observation with an electron microscope.

<Recording layer 103>
As the dye for forming the recording layer of the optical recording medium, a metal complex of the squarylium compound shown in Table 1 was used.

Each of the metal complexes of the squarylium compound described in Table 1 was ultrasonically dissolved in 2,2,3,3-tetrafluoropropanol at about 35 ° C., and a solution having a concentration of 0.5% by weight of the metal complex was obtained. Prepared.
About 0.5 g of this solution is dropped on the reflective layer 102 in a spiral shape from the outer periphery to the inner periphery, applied at a rotational speed of 2000 rpm by a spin coating method, and then heated in an oven at 70 ° C. for 30 minutes to form the recording layer 103. Formed. The film thickness of the groove (concave portion) where recording is performed in the recording layer was about 30 nm from cross-sectional observation with an electron microscope.

Table 1 shows the results of measuring the absorbance of the dye used in the disk thin film state at 405 nm, which is the wavelength of the blue-violet laser.

<Transparent protective layer 104>
A transparent dielectric thin film of ZnS—SiO ₂ (ZnS = 80 mol%, SiO ₂ = 20 mol%) is RF-sputtered on the recording layer 103 to protect the recording layer and improve recording signal quality and storage characteristics. A transparent protective layer 104 was formed by the method. The film thickness of this recording layer was 17 nm from cross-sectional observation with an electron microscope.

<Cover layer 105>
On the transparent protective layer 104, a cover sheet (trade name Opteria, manufactured by Lintec Co., Ltd.) having a thickness of 100 μm obtained by applying a transparent adhesive to a polycarbonate film sheet is bonded with a sheet roller, and then subjected to pressure defoaming for 15 seconds. Thus, the cover layer 105 was formed.

The BD-R type optical recording media of Examples 29 to 37 were manufactured using the materials, procedures, and prototype conditions described above. For these optical recording media, a disk evaluation machine (PDUSTEC ODU-1000) having a pickup head having a wavelength of 405 nm and a numerical aperture NA of 0.85 was used, and a shortest mark of 0.149 μm at a linear velocity of 4.92 m / sec. A signal of the RLL (1-7) modulation method was modulated with a ternary multi-pulse as shown in FIG. 2, and five tracks were recorded on the groove. Reproduction was performed at a reproduction power of 0.30 mW on the third track at the center of the five recorded tracks. After performing waveform equalization with the waveform equalizer, the value obtained by dividing the jitter of the timing difference between the rise and fall of the signal binarized through the limit equalizer and the rise of the clock signal by the window width T (jitter value) Was evaluated. The recording conditions of each example were set by optimizing the recording power and multipulse modulation so that the jitter value was minimized. In Table 2, the jitter value obtained by recording / reproduction and the peak value of the recording power shown in FIG. 2 are shown as Pwo.

As a result, it was confirmed that the optical recording media obtained in the examples satisfied the BD-R standards (jitter value: 7% or less, Pwo: 6 mW or less).
Further, Pwo was as low as 6 mW or less when recording was performed using the optical recording medium obtained in the example so that the jitter value was 7% or less. This indicates that the optical recording medium obtained in the example has high sensitivity photoresponsiveness to blue-violet laser light.

According to the present invention, it is possible to provide an optical recording medium containing a metal complex of a squarylium compound having a highly sensitive photoresponsiveness to blue-violet laser light.

Claims

Formula (I):

[Wherein, R 1 represents a hydrogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent, an alicyclic hydrocarbon group which may have a substituent, An aryl group which may have a substituent or a heterocyclic group which may have a substituent, R 2 represents a hydrogen atom, a hydroxyl group, a carboxyl group, a halogen atom, a nitro group, a cyano group, a substituent An amino group which may have a substituent, an alkyl group which may have a substituent, an alkoxyl group which may have a substituent, an aralkyl group which may have a substituent, and a substituent. Represents an alicyclic hydrocarbon group which may be substituted, an aryl group which may have a substituent or a heterocyclic group which may have a substituent, and R 3 and R 4 are the same or different, Hydrogen atom, optionally substituted alkyl group, substituted Which may be an aralkyl group, which may have a substituent the alicyclic hydrocarbon group, an optionally substituted aryl group, optionally substituted heterocyclic group, or NR 5 R 6 (wherein R 5 and R 6 are the same or different and have a hydrogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent, or a substituent. Represents an alicyclic hydrocarbon group which may be substituted, an aryl group which may have a substituent or a heterocyclic group which may have a substituent, and R 3 and R 4 are adjacent nitrogen atoms And may form an alicyclic heterocyclic ring which may have a substituent. However, R 3 and R 4 do not represent a hydrogen atom at the same time.] An optical recording medium containing a metal complex of a squarylium compound represented by:
R 3 and R 4 are the same or different and are a hydrogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent, or an alicyclic which may have a substituent. A hydrocarbon group, an optionally substituted aryl group or an optionally substituted heterocyclic group, or R 3 and R 4 together with the adjacent nitrogen atom are substituted The optical recording medium according to claim 1, wherein an alicyclic heterocyclic ring which may have
The optical recording medium according to claim 1, wherein at least one of R 3 and R 4 is NR 5 R 6 (wherein R 5 and R 6 are as defined above).
The optical recording medium according to claim 1, wherein one of R 3 and R 4 is NR 5 R 6 (wherein R 5 and R 6 are as defined above), and the other is a hydrogen atom.
At least one of R 5 and R 6 is of the formula (II):

[Wherein W is a nitrogen atom or C—R 7 (wherein R 7 is a hydrogen atom, a hydroxyl group, a carboxyl group, a halogen atom, a nitro group, a cyano group, an amino group which may have a substituent, An alkyl group which may have a substituent, an alkoxyl group which may have a substituent, an aralkyl group which may have a substituent, and an alicyclic hydrocarbon which may have a substituent A group, an aryl group which may have a substituent or a heterocyclic group which may have a substituent, and X represents a nitrogen atom or C—R 8 (wherein R 8 represents the above R 7 represents a nitrogen atom or C—R 9 (wherein R 9 is as defined above for R 7 ), and Z represents a nitrogen atom or C—R 10 (wherein R 7 10 represents a a) synonymous with the R 7, when W is C-R 7 X is a C-R 8 R 7 and R 8 may each form two or hydrocarbon ring which may have a substituent together with the carbon atom adjacent, X is C-R 8 Y is C- When R 9 is R 9 , R 8 and R 9 may be combined with two adjacent carbon atoms to form an optionally substituted hydrocarbon ring, wherein Y is C—R 9 And when Z is C—R 10 , R 9 and R 10 may be combined with two adjacent carbon atoms to form an optionally substituted hydrocarbon ring]. The optical recording medium according to claim 3 or 4, wherein:
6. The optical recording medium according to claim 5, wherein W is a nitrogen atom, X is CR 8 , Y is CR 9 , and Z is CR 10 .
7. The optical recording medium according to claim 5, wherein one of R 5 and R 6 is formula (II) and the other is a hydrogen atom.
R 1 and R 2 are the same or different and are each a hydrogen atom, an optionally substituted alkyl group, an optionally substituted aryl group or an optionally substituted heterocyclic group. The optical recording medium according to any one of claims 1 to 7, wherein
The optical recording medium according to any one of claims 1 to 8, wherein the metal is nickel, cobalt, aluminum, copper, zinc or iron.
The optical recording medium according to any one of claims 1 to 8, wherein the metal is nickel or cobalt.
11. The optical recording medium according to claim 1, wherein recording is possible with a recording wavelength of 350 to 530 nm.
Formula (Ia):

[Wherein, R 1 represents a hydrogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent, an alicyclic hydrocarbon group which may have a substituent, An aryl group which may have a substituent or a heterocyclic group which may have a substituent, R 2 represents a hydrogen atom, a hydroxyl group, a carboxyl group, a halogen atom, a nitro group, a cyano group, a substituent An amino group which may have a substituent, an alkyl group which may have a substituent, an alkoxyl group which may have a substituent, an aralkyl group which may have a substituent, and a substituent. Represents an alicyclic hydrocarbon group which may be substituted, an aryl group which may have a substituent or a heterocyclic group which may have a substituent, and R 5a has a hydrogen atom and a substituent. An optionally substituted alkyl group, an optionally substituted aralkyl group, An alicyclic hydrocarbon group which may have a substituent, an aryl group which may have a substituent or a heterocyclic group which may have a substituent, W represents a nitrogen atom or C— R 7 (wherein R 7 is a hydrogen atom, a hydroxyl group, a carboxyl group, a halogen atom, a nitro group, a cyano group, an amino group which may have a substituent, or an alkyl group which may have a substituent) , An alkoxyl group which may have a substituent, an aralkyl group which may have a substituent, an alicyclic hydrocarbon group which may have a substituent, or a substituent. Represents an aryl group or an optionally substituted heterocyclic group), X represents a nitrogen atom or C—R 8 (wherein R 8 has the same meaning as R 7 above), and Y represents Represents a nitrogen atom or C—R 9 (wherein R 9 is as defined above for R 7 ), and Z is Nitrogen atom or C-R 10 (wherein, R 10 is a is same meaning as the R 7) represents, W is the C-R 7 a and X are each R 7 and R 8 when it is C-R 8 A hydrocarbon ring which may have a substituent may be formed together with two adjacent carbon atoms, and when X is C—R 8 and Y is C—R 9 , R 8 and R 9 may be combined with two adjacent carbon atoms to form a hydrocarbon ring which may have a substituent, and Y is C—R 9 and Z is C—R 10 . In some cases, R 9 and R 10 may be combined with two adjacent nitrogen atoms to form a hydrocarbon ring which may have a substituent, and a metal complex of a squarylium compound represented by:
The metal complex according to claim 12, wherein W is a nitrogen atom, X is CR 8 , Y is CR 9 , and Z is CR 10 .
The metal complex according to claim 12 or 13, wherein R 5a is a hydrogen atom.
R 1 and R 2 are the same or different and are each a hydrogen atom, an optionally substituted alkyl group, an optionally substituted aryl group or an optionally substituted heterocyclic group. The metal complex according to any one of claims 12 to 14, which is
The metal complex according to any one of claims 12 to 15, wherein the metal is nickel, cobalt, aluminum, copper, zinc or iron.
The metal complex according to any one of claims 12 to 15, wherein the metal is nickel or cobalt.