KR20110050663A - 2-benzyl-4-(3,4-dichlorophenyl)-5-methylimidazole compound - Google Patents

Abstract

여기서, X₁ 및 X₂는 동일하거나 상이하며, 수소 원자, 염소 원자 또는 브롬 원자를 나타낸다.An object of the present invention is a 2-benzyl-4- (3,4-dichlorophenyl) -5-methylimidazole compound useful as an antioxidant to copper surfaces, as a curing agent for epoxy resins or as an intermediate for pharmaceuticals and agricultural chemicals. To provide.
The 2-benzyl-4- (3,4-dichlorophenyl) -5-methylimidazole compound is represented by formula (I). This compound was prepared by heating a 2-halogenated-3 ', 4'-dichloropropiophenone compound in an organic solvent in the presence of a dehydrohalogenating agent. It can be synthesized by reacting with an arylacetamidine compound.

Here, X ₁ and X ₂ are the same or different and represent a hydrogen atom, a chlorine atom or a bromine atom.

Description

2-benzyl-4- (3,4-dichlorophenyl) -5-methylimidazole compound {2-BENZYL-4- (3,4-DICHLOROPHENYL) -5-METHYLIMIDAZOLE COMPOUND}

The present invention relates to novel 2-benzyl-4- (3,4-dichlorophenyl) -5-methylimidazole compounds.

As an imidazole compound similar to the compound of the present invention, for example, 2- (2,4-dichloro-benzyl) -5- (3,4-dichloro-phenyl) -1H-imidazole is disclosed in Patent Document 1 have. However, no imidazole compound is disclosed in which the methyl group is bound to the 4 (5) -position of the imidazole ring.

JP-T-2003-500357 (7 pages, 51 pages)

It is an object of the present invention to provide novel 2-benzyl-4- (3,4-dichlorophenyl) -5-methylimidazole compounds.

In order to solve the above problem, the inventors have conducted extensive and intensive investigation. As a result, the inventors have been able to synthesize a novel 2-benzyl-4- (3,4-dichlorophenyl) -5-methylimidazole compound represented by formula (I), thus completing the present invention. I found out.

That is, the present invention includes the following aspects in its broadest configuration:

(1) 2-benzyl-4- (3,4-dichlorophenyl) -5-methylimidazole compound represented by formula (I):

In the above formula, X ₁ and X ₂ are the same or different and represent a hydrogen atom, a chlorine atom or a bromine atom.

The 2-benzyl-4- (3,4-dichlorophenyl) -5-methylimidazole compound of the present invention is a curing agent or curing agent of an epoxy and epoxy resin on the surface of metals, especially copper (including copper alloys) It is useful as an accelerator and also as an intermediate raw material in the medical and agrochemical fields.

The following will describe the invention in detail.

The 2-benzyl-4- (3,4-dichlorophenyl) -5-methylimidazole compound of the present invention is represented by the following formula (I), and examples thereof include the following compounds:

2-benzyl-4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (2-chlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (3-chlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (4-chlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (2,3-dichlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (2,4-dichlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (2,5-dichlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (2,6-dichlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (3,4-dichlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (3,5-dichlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (2-bromobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (3-bromobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (4-bromobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (2,3-dibromobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (2,4-dibromobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (2,5-dibromobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (2,6-dibromobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (3,4-dibromobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (3,5-dibromobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (3-bromo-2-chlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (4-bromo-2-chlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (5-bromo-2-chlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (2-bromo-6-chlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (2-bromo-3-chlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (4-bromo-3-chlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (5-bromo-3-chlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (2-bromo-5-chlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole,

2- (2-bromo-4-chlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole, and

2- (3-bromo-4-chlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole.

In the above formula, X ₁ and X ₂ are the same or different and represent a hydrogen atom, a chlorine atom or a bromine atom.

The 2-benzyl-4- (3,4-dichlorophenyl) -5-methylimidazole compound of the present invention can be synthesized according to known methods. For example, as shown in the following scheme, the compound is a 2-halogenated-3 ', 4'-dichloropropiophenone compound with a dehydrohalogenating agent in an organic solvent. It can be synthesized by reacting with an arylacetamidine compound while heating in the presence of an agent).

Wherein X ₁ and X ₂ are the same as defined above, and X ₃ represents a chlorine atom, bromine atom or iodine atom.

In the above-described reaction, the amount of the arylacetamide compound used is preferably 0.8 to 1.5 times mole, more preferably 0.9 to 1.1 times mole with respect to the 2-halogenated-3 ', 4'-dichloropropiophenone compound. Ratio. The amount of the dehydrohalogenating agent used is preferably 1 to 10 times the proportion of the 2-halogenated-3 ', 4'-dichloropropiophenone compound.

As the 2-halogenated-3 ', 4'-dichloropropiophenone compound, 2-chloro-3', 4'-dichloropropiophenone, 2-bromo-3 ', 4'-dichloropropiophenone and 2 -Iodo-3 ', 4'-dichloropropiophenone may be mentioned.

The 2-halogenated-3 ', 4'-dichloropropiophenone compound is obtained by halogenating the 2-position of 3', 4'-dichloropropiophenone. As the halogenation, chlorination or iodination is also possible, but the bromination reaction in which the same molar amount of bromine reacts with 3 ', 4'-dichloropropiophenone is the simplest and easiest.

As 3 ', 4'- dichloropropiophenone, a commercially available thing can be used as a reagent.

The arylacetamidine compound may be obtained by reacting aryacetamidine hydrochloride with an alkali agent and removing hydrogen chloride. In the synthesis reaction of the above-mentioned imidazole compound, it is also possible to use arylacetamidine hydrochloride or to use salts of arylacetamidine compounds having a conventionally known inorganic or organic acid in place of the aacetamidine.

The arylacetamidine hydrochloride can be synthesized according to known methods. For example, as shown in the following scheme, the arylacetamidine hydride chloride reacts the benzyl cyanide compound with a lower alcohol such as hydrogen chloride gas and ethanol to convert to arylacetimidate hydrochloride. It can be synthesized by further reacting with ammonia.

Here, X ₁ and X ₂ are the same as described above.

Examples of hydrochlorides of the arylacetamidine compounds obtained through the above reactions include the following compounds:

Phenylacetamidine hydrochloride,

(2-chlorophenyl) acetamidine hydrochloride,

(3-chlorophenyl) acetamidine hydrochloride,

(4-chlorophenyl) acetamidine hydrochloride,

(2,3-dichlorophenyl) acetamide hydrochloride,

(2,4-dichlorophenyl) acetamidine hydrochloride,

(2,5-dichlorophenyl) acetamidine hydrochloride,

(2,6-dichlorophenyl) acetamide hydrochloride,

(3,4-dichlorophenyl) acetamide hydrochloride,

(3,5-dichlorophenyl) acetamide hydrochloride,

(2-bromophenyl) acetamide hydrochloride,

(3-bromophenyl) acetamide hydrochloride,

(4-bromophenyl) acetamide hydrochloride,

(2,3-dibromophenyl) acetamide hydrochloride,

(2,4-dibromophenyl) acetamide hydrochloride,

(2,5-dibromophenyl) acetamidine hydrochloride,

(2,6-dibromophenyl) acetamidine hydrochloride,

(3,4-dibromophenyl) acetamide hydrochloride,

(3,5-dibromophenyl) acetamide hydrochloride,

(3-bromo-2-chlorophenyl) acetamide hydrochloride,

(4-bromo-2-chlorophenyl) acetamide hydrochloride,

(5-bromo-2-chlorophenyl) acetamidine hydrochloride,

(2-bromo-6-chlorophenyl) acetamidine hydrochloride,

(2-bromo-3-chlorophenyl) acetamide hydrochloride,

(4-bromo-3-chlorophenyl) acetamide hydrochloride,

(5-bromo-3-chlorophenyl) acetamide hydrochloride,

(2-bromo-5-chlorophenyl) acetamidine hydrochloride,

(2-bromo-4-chlorophenyl) acetamidine hydrochloride, and

(3-bromo-4-chlorophenyl) acetamidine hydrochloride.

As the dehydrohalogenating agent, any known one can be used without limitation. Examples of such dehydrohalogenating agents include inorganic alkali compounds such as sodium hydroxide, potassium hydroxide, calcium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate and potassium bicarbonate; Organic base compounds, such as triethylamine and 1,8-diazabicyclo [5.4.0] -7-undecene (1,8-diazabicyclo [5.4.0] -7-undecene) (DBU); Metal alkoxides such as sodium methoxide and tert-butoxide, and the like.

As the reaction solvent, it is possible to dissolve the 2-halogenated 3 ', 4'-dichloropropiophenone compound and the arylacetamidine compound, and any known one can be used without limitation so long as it is not related to the reactions. Can be. Examples of such solvents include alcohols such as isopropyl alcohol and tert-butanol; Hydrocarbons such as hexane and toluene; Halogenated hydrocarbons such as chloroform and chlorobenzene; Esters such as ethyl acetate; Nitriles such as acetonitrile; Ethers such as tetrahydrofuran, dioxane and ethylene glycol dimethyl ether; Amides such as N, N-dimethylformamide (DMF) and N, N-dimethylacetamide (DMAC); Dimethyl sulfoxide (DMSO) and the like. These solvents can be used in combination.

The reaction temperature is preferably at room temperature to reluxing temperature and the reaction time is preferably 1 to 10 hours. The reaction can be carried out mainly at atmospheric pressure.

The 2-benzyl-4- (3,4-dichlorophenyl) -5-methylimidazole compound formed under the reaction conditions can be isolated mainly by post-treatment. For example, the crude product of the compound may be obtained by partitioning the reaction mixture between the aqueous and organic solvent layers after completion of the reaction and washing the organic solvent layer with water and then evaporating the organic solvent. The crude product may be further purified by recrystallization operation or the like.

Example

The following will specifically describe the present invention with reference to the examples, but the present invention should not be construed as being limited thereto. Reference Examples 1 and 2 also show synthesis examples of phenylacetamidine hydrochloride and 2-bromo-3 ', 4'-dichloropropiophenone, respectively.

Reference Example 1

(Synthesis of phenylacetamidine hydrochloride)

Into a solution consisting of 117.8 g (1.006 mol) of phenylacetonitrile and 55.8 g (1.21 mol) of dry ethanol, 44.6 g (1.22 mol) of hydrogen chloride gas were introduced at 5 to 10 ° C. over 4 hours. When the reaction solution was left at 4 ° C. for 1 day and further at room temperature for 2 days, ethyl phenylacetimidate hydrochloride precipitated as a white solid.

After trituration of the ethyl phenylacetimidade hydrochloride collected by filtration, a solution consisting of 35.6 g (2.09 mol) of ammonia and 246 g of dry ethanol was added thereto in portions with stirring under ice cooling. The mixture was then stirred for 2 hours under ice cooling and further stirred at room temperature overnight. After the insoluble matter of the white solid was removed by filtration, the filtrate was concentrated to dryness under reduced pressure to give 172.5 g (1.011 mol, 100.5% yield) of phenylacetamidine hydrochloride in the form of a pale yellow thick syrup.

Reference Yes  2

(Synthesis of 2-bromo-3 ', 4'-dichloropropiophenone)

To a solution consisting of 45.8 g (0.226 mol) of 3 ', 4'-dichloropropiophenone and 46 g of methanol, 36 g (0.2253 mol) of bromine were added dropwise at 62 to 65 ° C. over 50 minutes. After the reaction solution had cooled, it was partitioned between 75 g of toluene and 91 g of water. After washing the toluene layer with water and drying over magnesium sulfate, the solvent was evaporated under reduced pressure to give 64.3 g of 2-bromo-3 ', 4'-dichloropropiophenone in the form of a bright yellowish oil. 0.228 mol, yield 101.1%).

Example 1

(Synthesis of 2-benzyl-4- (3,4-dichlorophenyl) -5-methylimidazole)

A 2-bromo dispersion of 28.7 g (0.168 mol) of phenylacetamidine hydrochloride, 59 g (0.427 mol) of potassium carbonate and 210 ml of N, N-dimethylformamide was stirred at 50 ° C. for 30 minutes. 48.8 g (0.173 mol) of -3 ', 4'-dichloropropiophenone were added in portions at the same temperature, followed by further stirring at the same temperature for 4 hours. Thereafter, after cooling the reaction dispersion, it was partitioned between 800 ml of water and 300 ml of chloroform. After washing the chloroform layer twice with water, the chloroform was evaporated under reduced pressure, and then 150 ml of toluene was added to the resulting thick syrup form concentrate and stirred with heating to precipitate crystals. Precipitated crystals were collected by filtration and washed with toluene and then dried to give a creamy powder. The powder was recrystallized from acetonitrile to give 18.8 g (0.059 mol, 35.3% yield) of milky white powder crystals.

Melting points, Rf values on thin layer chromatography, and ¹ H-NMR and mass spectral data of the obtained crystals are as follows.

ㆍ mp. 158-161 ℃

TLC (silica gel, acetone): Rf = 0.70

¹ H-NMR (CDCl ₃ ) δ: 2.28 (s, 3H), 3.94 (s, 2H), 7.12-7.66 (m, 7H).

MS m / z (%): 316 (M ⁺ , 100), 301 (3), 281 (3), 239 (4), 198 (2), 171 (4), 144 (3), 122 (9 ), 103 (6), 91 (8), 77 (4).

Based on this spectral data, the obtained compound was identified as 2-benzyl-4- (3,4-dichlorophenyl) -5-methylimidazole represented by the following formula.

Example 2

(Synthesis of 2- (2-chlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole)

First, (2-chlorophenyl) acetamidine hydrochloride was synthesized according to the method of Reference Example 1, except that (2-chlorophenyl) acetonitrile was used instead of the phenylacetonitrile of Reference Example 1.

Next, the milky white powder crystals were subjected to the synthesis experiment according to the method of Example 1, except that (2-chlorophenyl) acetamidine hydrochloride was used instead of the phenylacetamidine hydrochloride of Example 1. Obtained by operation.

Melting points, Rf values on thin layer chromatography, and ¹ H-NMR and mass spectral data of the obtained crystals are as follows.

ㆍ mp. 150-152 ℃

TLC (silica gel, acetone): Rf = 0.58

¹ H-NMR (d ₆ -DMSO) δ: 2.38 (s, 3H), 4.09 (s, 2H), 7.27-7.80 (m, 7H).

MS m / z (%): 350 (M ⁺ , 23), 315 (100), 280 (3), 171 (2), 137 (3), 122 (10), 102 (4), 89 (3 ).

Based on this spectral data, the obtained compound was identified as 2- (2-chlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole represented by the following formula.

Example  3

(Synthesis of 2- (4-chlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole)

First, (4-chlorophenyl) acetamidine hydrochloride was synthesized according to the method of Reference Example 1, except that (4-chlorophenyl) acetonitrile was used instead of the phenylacetonitrile of Reference Example 1.

Next, the yellowish white powder crystals were used in the method of Example 1, except that (4-chlorophenyl) acetamidine hydrochloride was used instead of the phenylacetamidine hydrochloride of Example 1. It was obtained by performing a synthetic experiment according to.

Melting points, Rf values on thin layer chromatography, and ¹ H-NMR and mass spectral data of the obtained crystals are as follows.

ㆍ mp. 180-181 ℃

TLC (silica gel, acetone): Rf = 0.72

¹ H-NMR (d ₆ -DMSO) δ: 2.36 (s, 3H), 3.96 (s, 2H), 7.29-7.80 (m, 7H).

MS m / z (%): 350 (M ⁺ , 100), 335 (1), 315 (14), 279 (3), 190 (3), 175 (4), 164 (4), 137 (7 ), 125 (10), 122 (15), 102 (8), 89 (4), 75 (3).

Based on this spectral data, the obtained compound was identified as 2- (4-chlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole represented by the following formula.

Example  4

(Synthesis of 2- (2,4-dichlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole)

First, (2,4-dichlorophenyl) acetamidine hydrochloride is used in the method of Reference Example 1, except that (2,4-dichlorophenyl) acetonitrile is used instead of the phenylacetonitrile of Reference Example 1. Synthesized accordingly.

Next, white powder crystals were synthesized according to the method of Example 1, except that (2,4-dichlorophenyl) acetamidine hydrochloride was used instead of the phenylacetamidine hydrochloride of Example 1. Obtained by

Melting points, Rf values on thin layer chromatography, and ¹ H-NMR and mass spectral data of the obtained crystals are as follows.

ㆍ mp. 117-119 ℃

TLC (silica gel, acetone): Rf = 0.74

¹ H-NMR (d ₆ -DMSO) δ: 2.36 (s, 3H), 4.07 (s, 2H), 7.33-7.77 (m, 7H).

MS m / z (%): 386 (M + 2, 100), 384 (M ⁺ , 31), 349 (100), 299 (3), 279 (3), 193 (4), 171 (7) , 159 (9), 139 (10), 121 (6), 102 (5).

Based on this spectral data, the obtained compound was identified as 2- (2,4-dichlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole represented by the following formula.

Example  5

(Synthesis of 2- (3,4-dichlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole)

First, (3,4-dichlorophenyl) acetamidine hydrochloride is used in the method of Reference Example 1, except that (3,4-dichlorophenyl) acetonitrile is used instead of the phenylacetonitrile of Reference Example 1. Synthesized accordingly.

Next, the milky white powder crystals were synthesized according to the method of Example 1, except that (3,4-dichlorophenyl) acetamidine hydrochloride was used instead of the phenylacetamidine hydrochloride of Example 1. Obtained by

Melting points, Rf values on thin layer chromatography, and ¹ H-NMR and mass spectral data of the obtained crystals are as follows.

ㆍ mp. 194-195 ℃

TLC (silica gel, acetone): Rf = 0.67

¹ H-NMR (d ₆ -DMSO) δ: 2.33 (s, 3H), 3.96 (s, 2H), 7.25-7.77 (m, 6H).

MS m / z (%): 386 (M + 2, 100), 384 (M ⁺ , 78), 371 (1), 349 (7), 314 (9), 239 (7), 212 (3) , 198 (3), 171 (7), 159 (9), 139 (10), 122 (7), 102 (4), 89 (2).

Based on this spectral data, the obtained compound was identified as 2- (3,4-dichlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole represented by the following formula.

Example  6

(Synthesis of 2- (4-bromobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole)

First, (4-bromophenyl) acetamidine hydrochloride is synthesized according to the method of Reference Example 1, except that (4-bromophenyl) acetonitrile is used instead of the phenylacetonitrile of Reference Example 1. It became.

Next, the milky white powder crystals were subjected to the synthesis experiment according to the method of Example 1, except that (4-bromophenyl) acetamidine hydrochloride was used instead of the phenylacetamidine hydrochloride of Example 1. Obtained by running.

Melting points, Rf values on thin layer chromatography, and ¹ H-NMR and mass spectral data of the obtained crystals are as follows.

ㆍ mp. 207-208 ℃

TLC (silica gel, hexane: ethyl acetate = 1: 1): Rf = 0.43

¹ H-NMR (d ₆ -DMSO) δ: 2.07 (s, 3H), 3.92 (s, 2H), 7.21-7.78 (m, 7H).

MS m / z (%): 398 (M + 4, 46), 396 (M + 2, 100), 394 (M ⁺ , 62), 361 (2), 315 (11), 299 (3), 279 (3), 239 (4), 198 (5), 183 (3), 171 (10), 140 (8), 122 (20), 102 (14), 89 (6), 75 (3).

Based on this spectral data, the obtained compound was identified as 2- (4-bromobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole represented by the following formula.

Example  7

Each of the imidazole compounds synthesized in Examples 1 to 6 and surface treatment liquids containing 2-phenylimidazole as an active ingredient in addition to these compounds were synthesized. A chemical film was formed on the copper surface by contacting each of the treatment liquids with copper and measuring the wetting time of the molten solder, thereby measuring the antioxidant performance on the copper surface on which the imidazole compound acts. . In this case, it was determined that the shorter the wetting time, the better the antioxidant performance of the imidazole compound.

Details of the evaluation test are as follows.

(1) Preparation of Surface Treatment Liquid:

After dissolving the imidazole compound, acid, metal salt, and halogen compound in ion exchanged water to achieve the composition described in Table 1, the pH was adjusted with ammonia water to prepare a surface treatment liquid.

(2) surface treatment method:

The test piece was degreased whose material was a copper metal (copper plate having a size of 5 mm x 50 mm x 0.3 mm) and then subjected to soft etching. After the test piece was immersed in the surface treating liquid at a predetermined temperature for a predetermined time to form a chemical film on the copper surface, the test piece was washed with water and dried.

(3) measurement of wet time

The surface treated test piece was immersed in post flux (trade name "JS-64MSS" manufactured by Koki Corporation), and the solder wetting time (seconds) was determined by a solder wetting tester (SAT-2000, Manufactured by Rhesca. The solder used was a tin-lead eutectic solder (trade name: H63A, manufactured by Senju Metal Industry Co., Ltd.) and the measurement conditions were as follows: soldering temperature 240 ° C., immersion depth 2 mm, immersion speed 16 mm / second.

In this regard, the test pieces for which the solder wettability time was measured are (A) test pieces immediately after the surface treatment, (B) after being left in a constant temperature and humidity chamber for 96 hours at a temperature of 40 ° C. and a humidity of 90% relative humidity (RH). It was a test piece and (C) a test piece after further heating at 200 degreeC for 10 minutes.

The test results obtained were as shown in Table 1.

Exam number One 2 3 4 5 6 7 Composition of Surface Treatment Liquid (% Weight-Balance is Water) Imidazole:





2-benzyl-4- (3,4-dichlorophenyl) -5-methylimidazole (Example 1) 0.25 2- (2-chlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole (Example 2) 0.25 2- (4-chlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole (Example 3) 0.25 2- (2,4-dichlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole (Example 4) 0.20 2- (3,4-dichlorobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole (Example 5) 0.20 2- (4-bromobenzyl) -4- (3,4-dichlorophenyl) -5-methylimidazole (Example 6) 0.25 2-phenylimidazole 1.0 mountain:


Formic acid 5.0 Acetic acid 15 25 15 20 25 30 2.0 Lactic acid 5.0 Levulinic acid 10 Metal salt:



Copper acetate 0.10 0.10 0.10 Copper chloride (II) 0.08 Copper bromide (II) 0.04 Zinc acetate 1.0 1.0 1.0 0.80 Zinc chloride 0.10 halogen:





Ammonium chloride 0.05 Potassium chloride Ammonium bromide 0.04 0.04 0.04 Potassium bromide 0.01 Ammonium Iodide 0.04 Potassium Iodide 0.05 Copper iodide   pH 3.6 3.5 3.0 3.2 3.3 3.3 4.8 Surface treatment condition:
Treatment temperature (℃) 40 40 40 40 40 40 50 Immersion time (seconds) 60 120 120 90 180 90 180 Solder Wetting Time (sec):

(A) immediately after surface treatment 0.35 0.31 0.28 0.28 0.27 0.29 0.41 (B) after 96 hours at 40 ° C. and 90% relative humidity. 0.44 0.41 0.43 0.38 0.35 0.41 6.2 (C) After 96 hours at 40 ° C. and 90% relative humidity and heating at 200 ° C. for 10 minutes
0.82
0.77
0.81
0.56
0.61
0.72
10

According to the test results shown in Table 1, the surface treating liquids containing the 2-benzyl-4- (3,4-dichlorophenyl) -5-methylimidazole compound of the present invention as an active ingredient were coated on a copper surface. Since they can form chemical films that are excellent in wet and heat resistance, they are useful for antioxidant of copper surfaces.

According to the invention, 2-benzyl-4-, useful as an antioxidant and curing accelerator of epoxy resins on the surface of metals, especially copper (including copper alloys), and as an intermediate raw material in the medical and agrochemical fields (3,4-dichlorophenyl) -5-methylimidazole compound may be provided.

While the invention has been described in detail with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the scope thereof.

This application is Japanese Patent Application No. 2008-225632, filed September 3, 2008, Japanese Patent Application No. 2009-130022, filed May 29, 2009, and Japanese Patent Application No., filed June 12, 2009. Based on 2009-140655, the entire contents of which are incorporated herein by reference.

Claims (1)

In the 2-benzyl-4- (3,4-dichlorophenyl) -5-methylimidazole compound represented by formula (1):

Wherein X ₁ and X ₂ are the same or different and represent a hydrogen atom, a chlorine atom or a bromine atom.