JPH0465078B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to tetraarylboron-ammonium complexes as novel compounds. More specifically, the present invention relates to the general formula () (In the formula, R ₁ represents a hydrogen atom, a halogen atom, or a lower alkyl group, R ₂ represents a halogen atom, a lower alkyl group, or a lower alkenyl group,
R ₃ represents pyridine or imidazole optionally substituted with lower alkyl). Traditionally, arylboron compounds have the general formula () (In the formula, X represents a potassium atom, an ammonium group, or a quaternized organic nitrogen group, but the organic nitrogen group may further form a heterocycle containing a nitrogen atom.) Compound (see Japanese Patent Publication No. 54-1571) and general formula () (In the formula, Y represents a hydrogen atom, a halogen atom, or a lower alkyl group) (see US Pat. No. 3,211,679)
is known for its use as an underwater antifouling agent. However, it is not known that these are effective as industrial preservatives and fungicides. The present inventors have conducted extensive research into the use of phenylboron compounds as preservatives and fungicides. As a result, the novel tetraarylboron-ammonium complex represented by the general formula () has excellent antibacterial properties against molds such as Aspergillus, Penicillium, Rhizopus, and Fusarium, bacteria such as Bacillus and Pseudomonas, and yeasts. As a non-medical sterilizer and fungicide,
The present invention was completed based on the finding that it is particularly effective as an industrial preservative and fungicide. The tetraarylboron-ammonium complex of the present invention is chemically stable, exhibits sufficient bactericidal and fungicidal effects in acidic and alkaline regions, and does not cause precipitation or coloring even when various metal salts are present together. It is advantageous in practical terms as a sterilizing, disinfecting, preservative, and fungicidal agent because there is no fear of this occurring and it can also be incorporated into plastics. In the compound of the present invention of general formula (I), when R ₁ and R ₂ are halogen atoms, they are preferably bromine, chlorine or fluorine, and R ₁ and R ₂ are lower alkyl groups having 1 to 6 carbon atoms. Sometimes methyl, ethyl, propyl, isopropyl,
Preferably, it is a butyl group or an isobutyl group,
When R ₂ is a lower alkenyl group having 2 to 6 carbon atoms, it is preferably a vinyl group. _R3 is pyridine,
Imidazole and methylimidazole are preferred. (R ₃ ·H) is preferably in the form of a quaternized ammonium group, for example to form pyridinium, imidazolium, methylimidazolium. Next, preferred examples of the tetraphenylboron-ammonium complex of the present invention are shown in Table 1. The compound numbers shown in Table 1 are referenced in the Examples and Test Examples herein.

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[Table] The compounds of the present invention of the general formula () are of the general formula ()
It can be produced based on the following reaction formula by reacting sodium tetraarylboron with a hydrogen halide salt of a heterocyclic amine of general formula (). (In the formula, X represents a halogen atom, R ₁ , R ₂ ,
(R ₃ has the same meaning as above) The method for producing the compound of the present invention will be explained in detail below. First, the synthesis of sodium tetraarylboron of the general formula () used as a raw material in the production of the compound of the present invention is carried out as follows. First, in order to synthesize a compound in which R ₁ and R ₂ represent the same group in the general formula (), the formula (However, R ₁ , In a diethyl ether or tetrahydrofuran solution containing a 4 molar ratio of aryllithium or an excess amount thereof, a diethyl ether complex of boron trifluoride of 1 molar ratio is added as is or diluted with a solvent such as toluene. After the mixture was added dropwise while stirring and cooling, the mixture was allowed to react under reflux conditions for 1 hour. Next, while cooling and stirring the reaction solution, an aqueous solution of excess common salt, sodium carbonate, sodium hydroxide, etc. is added dropwise as a sodium source. After the reaction is complete, separate the upper organic layer and distill off the solvent to obtain white crystals, which are washed with a non-polar solvent such as toluene and dried to obtain the desired product represented by the general formula (). Sodium tetraarylboron is obtained as white crystals. If purification is required, the white crystals may be recrystallized using a lower alkanol solvent such as ethanol or isopropyl alcohol. Furthermore, in order to synthesize an asymmetric tetraarylboron compound in which R ₁ and R ₂ are different groups in the general formula (), first, an arylmagnesium halide or an arylyltium halide is reacted with boron trifluoride using the same method as above. After that, the formula is obtained from the reaction solution.

Either the symmetrical triarylboron represented by the formula is isolated or the molar ratio of these reactants is strictly controlled at 3:1 from the beginning of the reaction between arylmagnesium halide or aryllithium and boron trifluoride. After synthesizing triarylboron, an aryl group having a substituent (R ₂ ) different from the substituent (R ₁ ) on the aryl group of triarylboron

When [Formula] is introduced, an asymmetric tetraarylboron is synthesized. Sodium tetraarylboron of the general formula () thus obtained and a hydrogen halide salt of a heterocyclic amine of the general formula () were mixed with methanol,
It is dissolved in lower akanols such as ethanol and isopropyl alcohol, ketones such as acetone, and inert polar solvents such as water at a temperature of 10 to 60℃.
The reaction is completed by simply mixing and stirring for 30 to 2 hours.
As the reaction solvent, the above-mentioned solvents may be used alone or in combination. In addition, if the reaction product precipitates in the solvent as crystals, it can be separated, but usually the solvent is distilled off and concentrated, the crystals are separated, and the inorganic salts are removed by washing with water. After drying, a highly pure complex is obtained. The tetraarylboron-ammonium complex of the general formula () thus obtained can be further purified by recrystallization from a solvent such as methanol, ethanol, chloroform, dimethylformamide, etc., if necessary. Next, a method for producing sodium tetraarylboron, which is a raw material for the compound of the present invention, will be specifically explained using reference examples. Reference Example 1 Synthesis of tetra(4-chloro-phenyl)boron sodium Tetrahydrofuran solution of 4-chloro-phenylmagnesium chloride (1.2 mol) synthesized from paradichlorobenzene and magnesium
ml) into a 2-volume 4-necked flask, and add 35.5 g of boron trifluoride diethyl ether complex.
50 ml of a toluene solution of (0.25 mol) was added dropwise at 20 to 30°C while stirring and cooling the system in a water bath, and then the reaction mixture was heated under reflux conditions for 1 hour. After the reaction was completed, the reaction solution was cooled, and 200 ml of a saturated aqueous sodium carbonate solution was added dropwise thereto. The separated organic layer was collected and the solvent was distilled off to obtain white crystals. Add 300ml of toluene to this to loosen and separate the crystals,
After washing twice with 100ml of toluene and drying,
106 g (yield: 88%) of the title compound was obtained as white crystals with a melting point of 310°C. Next, the method for producing the compound of the present invention will be specifically explained using examples. Example 1 Synthesis of tetra(4-chlorophenyl)boron-pyridinium complex (compound No. 5) 24.0 g (0.05 mol) of sodium tetra(4-chlorophenyl) boron was dissolved in 200 ml of methanol and added to a 500 ml flask. ,to this
Pyridine hydrochloride 5.3 dissolved in 50ml methanol
g (0.05 mol) was added dropwise with stirring. After the dropping was completed, stirring was continued for 1 hour to complete the reaction. Thereafter, the solvent in the reaction solution was distilled off, and 100 ml of water was added to the precipitated crystals to loosen them and separate the crystals. The crystals were further washed with water and dried to obtain 24.9 g (yield: 92.6%) of the title compound as white crystals with a melting point of 157-161°C. The elemental analysis values are as follows. Measured value Calculated value C 64.7% 64.9% H 4.1% 4.1% Example 2 Synthesis of tetra(4-chlorophenyl)boron-pyridinium complex (compound No. 5) Using pyridine hydrobromide in place of pyridine hydrochloride, The reaction operation was carried out according to Example 1, and 26.0% of the title compound was obtained as white crystals with a melting point of 157-161°C.
g (yield 96.8%). The elemental analysis values are as follows. Measured value Calculated value C 64.6% 64.9% H 4.2% 4.1% Example 3 Tetra(4-fluorophenyl)boron-2-methylimidazolium complex (Compound No.
Synthesis of 8) 4.1 g (0.01 mol) of sodium tetra(4-fluorophenyl) boron in a 100 ml flask.
was dissolved in 40 ml of ethanol and added thereto, and 1.2 g (0.01 mol) of 2-methylimidazole hydrochloride dissolved in 20 ml of ethanol was added dropwise with stirring.
After the dropwise addition was completed, stirring was continued for 1 hour to complete the reaction. Thereafter, the solvent in the reaction solution was distilled off, and 50 ml of water was added to the precipitated crystals to loosen them and collect the crystals. The crystals were further washed with water and dried to obtain 4.3 g (yield: 90.2%) of the title compound as white crystals with a melting point of 205-207°C. The elemental analysis values are as follows. Measured value Calculated value C 70.5% 70.9% H 5.0% 4.9% Example 4 Tetra(4-fluorophenyl)boron-2-methylimidazolium complex (Compound No.
Synthesis of 8) Using isopropyl alcohol as the reaction solvent,
The procedure was carried out according to Example 3 to obtain 4.4 g of the title compound as white crystals with a melting point of 205-207°C (yield 92.9%).
I got it. The elemental analysis values are as follows. Measured value Calculated value C 70.5% 70.9% H 5.0% 4.9% Example 5 Synthesis of tetra(4-methylphenyl)boron-pyridinium complex (compound No. 1) 19.9 g of tetra(4-methylphenyl)boron sodium in a 500ml flask (0.05 mol) was dissolved in 200 ml of tetrahydrofuran, and 50 ml of an aqueous solution containing 4.0 g (0.05 mol) of pyridine and an equimolar amount of hydrochloric acid was added dropwise with stirring. The following treatment was carried out in the same manner as in Example 1, and the melting point was 183.
20.8 g of the title compound as white crystals at ~185°C
(91.3%). The elemental analysis values are as follows. Measured value Calculated value C 86.8% 87.0% H 7.4% 7.5% Example 6 Synthesis of triphenyl-(4-vinyl)phenylboron-2-methylimidazolium complex (compound No. 10) Example using acetone as the reaction solvent When triphenyl-(4-vinyl)phenylboron sodium and 2-methylimidazole hydrochloride were reacted in the same manner as in 3, 20.0 g (yield 93.7%) of the title compound was obtained as white crystals with a melting point of 234-236°C. . The elemental analysis values are as follows. Measured value Calculated value C 84.1% 84.2% H 6.9% 6.8% Another example of the tetraarylboron-ammonium complex of the present invention having the general formula () shown in Table 1 was prepared by a method similar to the above example. Compounds were also produced. When the tetraarylboron-ammonium complex of the present invention is used as an active ingredient in a preservative and fungicide, it can be formulated into emulsions, flowables (sols), wettable powders, liquids, etc. in accordance with conventional methods. It can be used in the same way as the preservative and fungicide. Next, a specific example of using the compound of the present invention as an active ingredient of an industrial preservative and fungicide will be illustrated as a reference example. Reference Example 2 (Wettable powder) 20 parts of Compound No. 1, 7 parts of lauryl sulfate, and 73 parts of clay were uniformly mixed and ground.
A hydrating powder containing 20% of the active ingredient is obtained. Reference Example 3 (Flowable agent) 20 parts of Compound No. 6, 2 parts of lauryl sulfate, 2 parts of xanthan gum, and 1 part of hydroxypropyl cellulose are uniformly mixed to obtain a flowable agent containing 20% of the active ingredient. Reference Example 4 (Emulsion) 1 part of Compound No. 11, 47 parts of dimethyl sulfoxide, 50 parts of tetrahydrofuran, and 2 parts of Solpol 800A (trade name of an emulsifier manufactured by Toho Chemical Industry Co., Ltd.) were uniformly dissolved to dissolve the active ingredient. An emulsion containing 1% of Next, the usefulness of the tetraarylboron-ammonium complex of the present invention as a preservative and a fungicide will be explained with reference to test examples. Test Example 1 Antibacterial test against various fungi The test was based on the agar dilution smear method (streak method). In other words, among the various bacteria known to degrade industrial materials, potato decoction medium (PH5.8) is used for filamentous fungi, and bouillon agar medium (PH7.0) is used for bacteria. Sterilized water was added to each test microorganism that had been cultured in advance on a test tube slant medium, and the resulting spore suspension was streaked onto the drug-containing medium using a platinum loop. Then, each culture medium was incubated at a temperature of 28 ± 2°C for 96 hours, and the presence or absence of growth of each bacteria was examined. ppm) was calculated. The results are shown in Table 2.

[Table] Test Example 2 Emulsion Paint Antifungal Effect Test A hydrating agent prepared according to Reference Example 2 was added so that the active ingredient reached the specified concentration of the emulsion paint, and the mixture was applied to wood chips and paper and air-dried. . A mold resistance test was conducted in accordance with JIS Z 2911-7 paint test. For wood chips, 3 days, 7 days, and 14 days after culturing and after 3 months of natural storage (27℃, 98% humidity); for paper, 3 days, 7 days, and 14 days after coating. The degree of occurrence was investigated using the following criteria. The results are shown in Tables 3 and 4. Mold occurrence investigation standard 3: No mycelial growth is observed on the inoculated part of the sample or test piece. 2: The area of mycelia growth observed on the inoculated part of the sample or test piece does not exceed one-third of the total area. 1: The area of mycelia growth observed in the inoculated part of the sample or test piece exceeds one-third of the total area. Comparative drug A in Tables 3 and 4 contains 2% of 2,4-thiazolylbenzimidazole and 1,2-benzisothiazoline as active ingredients.
Comparative agent B is a commercially available fungicide containing 4% 3-one and 10% bis(tributyltin) oxide; these comparative agents are also referenced in the following test examples.

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[Table] Test Example 3 Preservative effect test on glue A flowable agent prepared according to Reference Example 3 was added to carboxymethyl cellulose (hereinafter referred to as CMC) 9% glue and potato starch 10% glue so that the active ingredient reached a predetermined concentration. After each was added and mixed uniformly, the mixture was placed in a synthetic resin cup, covered with aluminum foil, and stored in a constant temperature chamber (30°C). After 7 and 11 days of storage, the test paste was streak-cultured (at 37°C for 48 hours) on a bouillon agar medium, and the status of bacterial growth was investigated according to the following criteria. The results are shown in Tables 5 and 6. Investigation criteria +: Glue where bacteria have grown -: Glue where bacteria have not grown Comparative drug C contains 20% parachloromethaxylenol and 2-bromo-2-
It is a commercially available fungicide containing 20% of nitropropane-1,3-diol.
-The following formula described in Publication No. 6235 Comparative drug E is disclosed in Japanese Patent Application Laid-open No. 51-62831.
The following formula described in the publication Comparative drug F is disclosed in Japanese Patent Application Laid-Open No. 39-28579.
The following formula described in the publication: Comparative drug G is tri-(p-fluorophenyl)borane pyridine represented by the following formula described in the same publication: It is triphenylborane imidazole represented by The latter two were used as comparative drugs because they have similar structures to the compounds of the present invention.

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[Table] Test Example 4 Wood fungicidal effect test The test method was conducted in accordance with the method for testing the efficacy of wood fungicides described in the Japan Wood Preservation Association Standard No. 2 (1979 edition). That is, an emulsion prepared according to Reference Example 4 was diluted with xylene so that the active ingredient reached a predetermined concentration, and a piece of wood (pine wood with a size of 2.5 cm x 2.5 cm x 0.5 cm) was placed in the emulsion, and a piece of potato was placed in front of the emulsion. Decoction (20% potato starch and 2% glucose)
Two types were used: one that was immersed in a PD medium (hereinafter referred to as PD medium) for 3 minutes to absorb the nutrient solution and dried at 60℃, and the other that was not immersed in such a PD medium and did not absorb the nutrient solution]. absorb the drug. This piece of wood was then air-dried for two days and used as a test specimen. This specimen was placed in a Petri dish, and the test bacteria [Aspergillus niger] was cultured on a potato decoction agar medium specified in JIS Z 2911.
ATCC9642, Penicillium funoculosum ATCC9644Rizopus
stolonifer (Rhizopus stolonifer)
IFO6354, Aureobasidium pullulans IFO6353,
Using a brush, apply 1 ml of a mixed spore solution (a mixture of four types of single spore suspensions in equal amounts) of Gliocladium virens (ATCC9645) to the test specimen. Cover the Petri dish and culture at a temperature of 26±2°C and a humidity of 70-80%. The investigation was carried out after 3 days, 7 days, 14 days, 21 days and 28 days after culture.
After a day, the mold growth status of the test specimen was investigated according to the following criteria. The results are shown in Tables 7 and 8. Investigation Criteria 3: No mold growth is observed on the test specimen. 2: Mold growth is observed only on the sides of the test piece. 1: Mold growth is observed on one-third or less of the area of the upper surface of the test piece. 0: Mold growth is observed on one-third or more of the area of the upper surface of the test piece. In addition, comparative drug H contains 2,4- as an active ingredient.
A commercially available fungicide containing 2% thiazolylbenzimidazole, 4% 1,2-benzisothiazolin-3-one, and 1% diiodomethyl paratolyl sulfone.

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Claims (1)

[Claims] 1. General formula: (In the formula, R ₁ represents a hydrogen atom, a halogen atom, or a lower alkyl group, R ₂ represents a halogen atom, a lower alkyl group, or a lower alkenyl group,
A tetraarylboron-ammonium complex represented by R ₃ represents pyridine or imidazole which may be substituted with a lower alkyl group.