NO177593B - The reaction product of a dialkyltin compound with N-cyclohexyl-N'-hydroxy-diazenium oxide, agents having bactericidal and fungicidal action and wood preservative containing these compounds and the use of said agents - Google Patents

Description

The invention relates to the reaction product of a dialkyl tin compound with N-cyclohexyl-N'-hydroxy-diazenium oxide, as well as agents with bactericidal and fungicidal action, which are suitable as wood preservatives, disinfectants, preservatives for technical products and as biocidal finishes for textiles, plastics and building materials.

The triorganotin compounds' strong effect against microorganisms, e.g. harmful fungi and bacteria are known. With the trialkyltin compounds, the optimum effect occurs when the total number of C atoms in the alkyl groups bound to the tin atom is from 9 to 12. Shorter or longer alkyl groups reduce the biocidal effect. Compared to the trialkyltin compounds, the known dialkyltin compounds show a very low biocidal effect (International Tin Research Institute, publication no. 559, 1979; Bokranz, Plum*, Fortschritte der chemischen Forschung, volume 16, issue 3/4, p. 377) .

Another group of biocides, which are mainly used as wood preservatives, is described in DE-C-1 024 743. It concerns metal salts of N-N<1->alkyl-hydroxy-diazeniumoxy-der or N-cyclohexyl-N<1->hydroxy-diazenium oxides (abbreviated as MeHDO). A disadvantage of these compounds is that high application concentrations are required to protect the wood, and the effect is relatively low against fungi that stain the wood.

For these reasons, mixtures of metal salts of N-cyclohexyl-N'-hydroxy-diazenium oxide with other biocides were proposed to increase the effect or extend the spectrum of action (DE-A-2 336 290, DE-A-2 341 882 and EP-B-0 072 426).

It is also known that the conversion product TBT-HDO, produced from tri-n-butyltin chloride and the potassium salt of N-cyclohexyl-N<1->hydroxy-diazenium oxide (K-HDO), exhibits a very good biocidal effect (DE-A 2 633 452).

It was now surprisingly found that reaction products of dialkyltin compounds with N-cyclohexyl-N'-hydroxydiazenium oxide (abbreviated as R2Sn-HD0) show a very good effect against bacteria and fungi, especially gram-negative bacteria as well as fungi that destroy and stain the wood .

The invention relates to the reaction product of a dialkyltin compound with N-cyclohexyl-N'-hydroxy-diazenium oxide

(R2Sn-HDO), which turnover product is characterized by having the general formula

in which R is an alkyl radical with 1-12 carbon atoms, whereby the radicals can be the same or different, especially 3-8, carbon atoms, preferably an n-alkyl radical such as an n-propyl-, n-butyl-, n-hexyl- or n-octyl residue, whereby the individual residues R can be the same or different. The di-n-butyltin compound (R=n-butyl, DBT-HDO) is therefore particularly preferred.

The invention further relates to bactericidal and fungicidal agents, which are characterized by the fact that, in addition to liquid or solid carriers, they contain compounds according to the invention, for use as a wood preservative, disinfectant, preservative for technical products and as a biocidal finish for textiles, plastics and building materials.

The R2Sn-HDO compounds are suitably used in the form of preparations such as solutions, emulsions, dispersions with or without binders or with solid carriers or diluents and possibly with the addition of wetting, binding, emulsifying and dispersing aids.

Suitable solvents are, for example, alcohols, white spirit, toluene, xylene.

For the production of aqueous preparations, the agents according to the invention can be used in the form of stable, aqueous concentrates, which contain common emulsifiers, preferably non-ionic emulsifiers such as alkylaryl polyglycol ethers.

The agents according to the invention are excellently usable

in the form of preparations, especially for wood protection, for example for freshly cut wood, which is easily attacked by bacteria and fungi such as Aspergillus and Trichoderma species. Likewise, they are suitable for the treatment of building wood materials, which are protected by the biocidal effect of the active substances according to the invention against

fungus that destroys tissue and also against bacterial attack.

Furthermore, the agents according to the invention are suitable for biocidal finishing of aqueous paint systems, for example dispersions, in terms of storage preservation and also protection against attack of the paint by bacteria and fungi, especially also against attack of aqueous systems for painting wood, for example alkyd resin dispersions, by fungi which gives blue coloration.

Furthermore, aqueous preparations can be used for biocidal finishing of various materials such as paper, cardboard, plastic, textiles, adhesives, building materials and leather.

A further area of application is the finishing of coloring liquids against unwanted microorganisms, e.g. for circuit cooling water, manufacturing water in paper production or drilling and cutting oil.

The concentration of active substance lies, depending on the area of application, in the range from 0.1 to 5% (wood protection), 0.05 - 3% (finishing of paint systems, paper, textiles, building materials, etc.) or 0.0001 - 0.2% (cooling and manufacturing water, drilling and cutting oil).

In order to make the spectrum of action wider, to achieve a particular effect against particular microorganisms or for insecticidal applications, the compounds according to the invention can be combined with other active substances. Suitable active substances include: copper naphthenate, copper 8-oxyquinoline, N,N'-dimethyl-N V-phenyl-N'-fluorodichloromethylthiosulfonyldiamide, N-cyclohexyl-N-methoxy-2,5-dimethylfuran-3- carboxylic acid amide, 3-iodo-2-propynylbutyl carbamate, benzimidazole-2-carbamic acid methyl ester, N-trichloromethylthiophthalimide, l-{[2-(2,4-dichlorophenyl)-1,3-dioxolan-2-yl] methyl}-1H-1,2,4-triazole, γ-hexachlorocyclohexane and synthetic pyrethroids such as 3-(2,2-dichlorovinyl-2,2-dimethyl)cyclopropane-1-carboxylic acid-α-cyano-3-phenoxybenzyl ester.

On- or the introduction of the agent can take place in a freely chosen manner, e.g. by applying, spraying, immersion or by industrial methods such as e.g. pressure or vaccum impregnation.

The compounds according to the invention are produced using the following reaction equation.

(X = halogen)

According to the invention, diorganotin halides R2SnX2 are reacted with alkali salts of N-cyclohexyl-N'-hydroxy-diazenium oxide (Me-HDO) at temperatures from 50-60 Ci aqueous alcoholic solution or organic solvents such as hexane, whereby the product precipitates into the organic phase. The starting products can be prepared using known methods (International Tin Research Institute, Publication No. 559, 1979; Bokranz, Plum; Fortschritte der chemischen Forschung, Volume 16, Issue 3/4, p. 377; DE-A-2 6 33,452) or can be obtained commercially (SCHERING AG, BASF).

The diorganotin compounds R2Sn-HDO according to the invention surprisingly exhibit a broad spectrum of action with good action both against gram-positive and also gram-negative bacteria as well as against fungi that destroy and stain the wood (Tables 1 and 2). In particular, this also applies to compounds with alkyl residues, which contain more than 4 C atoms, e.g.

di-n-octyltin compound. This is particularly surprising,

as, for example, tri-n-octyltin compounds, unlike tri-n-butyltin compounds, do not show biocidal effects.

Remarkable is the significantly lower impact on the environment of the compounds according to the invention compared to the triorganotin compounds:

As the present comparison shows, for example, from TBT-HDO during 6 days of storage at 65° C, an amount almost six times greater is released into the environment than with DBT-HDO according to the invention.<;>

As the LD,-0 values (p.o. rat) show, DBT-HDO according to the invention also shows a significantly lower toxicity towards warm-blooded animals than TBT-HDO.

The toxicity towards fish and daphnia is an order of magnitude less for the diorganotin compounds R2Dn-HDO according to the invention than for the triorganotin compounds R^Sn-HDO.

Thus, the compounds according to the invention prove to be excellent active substances as biocides with a broad spectrum of action against harmful organisms with at the same time a low burden on the environment.

Example 1

Preparation of bis(N-cyclohexyl-diazeniumdioxy)di-n-butyltin (DBT-HDO)

To a solution of 151.9 g (0.5 mol) di-n-butyltin chloride (DBTC1) in 500 ml methanol is added over approx. 20 minutes 182.3 g (1 mol) of the potassium salt of N-cyclohexyl-N<1->hydroxy-diazenium oxide in the form of a 30% aqueous solution. The mixture is then stirred for 1 hour at 50 - 60° C Thereby, an oily phase is separated in the lower part of the reaction vessel, which is then separated and taken up in 500 ml of heptane. After drying with anhydrous sodium sulfate and filtration, the solvent is distilled off in a vacuum. As a residue, a solid, weakly coloured, powdery product with the formula is left behind

Yield: 222 g (85.5% of theory)

Analysis for C2()H40N4O4Sn (MV: 519.26):

Calculated: C 46.26 H 7.77 N 10.79 0 12.32 Sn 22.86 % Found: C 46.12 H 7.71 N 10.88 0 12.40 Sn 22.90 %

Example 2

Preparation of bis(N-cyclohexyl-diazeniumdioxy)di-n-pentyltin (DPT-HDO)

The preparation proceeded analogously to example 1 from 0.5 mol di-n-pentyltin dichloride and 1 mol N-cyclohexyl-N'-hydroxy-diazenium oxide

DPT-HDO is an oily, yellow liquid.

Yield: 237 g (86.6% of theory)

Analysis for <C>22<H>44N404Sn (MV 547.31):

Calculated: C 48.28 H 8.10 N 10.24 0 11.69 Sn 21.69 % Found: C 48.43 H 8.03 N 10.11 0 10.60 Sn 21.83 %

Example 3

Preparation of bis(N-cyclohexyl-diazeniumdioxy)di-n-octyltin

(DOT-HDO)

The preparation proceeded analogously to example 1 from 0.5 mol of di-n-octyltin dichloride and 1 mol of N-cyclohexyl-N'-hydroxydiazenium oxide.

DOT-HDO is an oily, yellow liquid.

Yield: 261.7 g (82.9% of theory)

Analysis for C2gH56N404Sn (MV: 631.47):

Calculated: C 53.26 H 8.94 N 8.87 O 10.13 Sn 18.80% Found: C 52.35 H 8.82 N 8.96 O 10.24 Sn 18.63%

Bactericidal effect

The bactericidal investigation of the compound according to the invention DBT-HDO (compare, example 1) took place in an agar diffusion test (compare Table 1). DST agar was inoculated with a drop of a 1:10 dilution of Miller-Hinton fluid of the test germs. After 2 hours of pre-diffusion at 22° C, paper filters were applied which had been immersed in solutions of active substance with different concentrations. After 24 hours of exposure, the inhibition height was determined (distance of the cloudiness from the edge of the paper filter in mm).

Fungicidal effect

The inhibitory effect of the products according to the invention against fungi was investigated in a "filter application test"

(compare. Table 2). To do this, round paper filters (diameter 5.5 cm) were immersed in ethanolic solutions with different contents of active substance. After drying at room temperature, the filters were placed in Petri dishes on plate-counting agar, which had been inoculated with a spore suspension. Biomalz agar 8° Bg served as nutrient medium, growth took place for 3 weeks at 30° C. Then the size of the zones of inhibition (distance of the fungal growth from the edge of the filter in mm) around the samples was determined.

For comparison of the fungicidal action against basidiomycetes, in accordance with DIN 52 176 blocks of pine heartwood (5 cm x 2.5 cm x 1.5 cm, fiber direction 5 cm) were immersed in the solution with stepwise concentrations of the active substance DBT-HDO ( compare Example 1) in acetone.

For comparison purposes, the starting materials di-n-butyltin dichloride and the K-salt of N-cyclohexyl-N<1->hydroxy-diazenium oxide were included in the investigations.

The impregnated bricks were stored for 4 weeks in a climate room with 20° C air temperature and 65% relative humidity. They were then subjected to a washout according to DIN EN 84. After drying, the treated blocks together with an untreated comparison block were added to a pure culture of Coniophora puteana in Kolle dishes and then exposed to attack by the fungi for 16 weeks at 32° C and 70% relative humidity. The effect of the fungi on the individual bricks was determined by calculating the weight losses (calculated on the dry weights). The limit values thus reached, which are expressed by two numbers, the lower of which is the highest amount of preservative (in kg/m 3 wood), at which an attack still takes place (weight loss over 3%), and the larger the lowest amount , from which there is no longer any attack, are listed in Table 3.

Formulation example 1

A colorless wood protection primer that contains little binder and consists of

shows a good penetration ability and can be applied, for example, by dipping or brushing on in amounts of 100 - 200 g/m 2 on the wooden surface.

Formulation example 2

A colored wood protection glaze, consisting of

3 parts by weight reaction product from Example 3.

is suitable for painting smaller wooden building parts such as window frames, doors, etc.

Formulation example 3

A solution of active substance for biocide protection of textiles, e.g. cotton canvas, consisting of

3.0 parts by weight reaction product from Example 1,

3.4" micronized polyethylene wax,

95.6 " odorless synthetic isoparaffin,

can be stirred by spraying the solution on the materials to be treated or by immersing or wetting the materials to be treated.

Claims (6)

Formulation example 4 A formulation which can be diluted with water, and which consists of 30 parts by weight of reaction product from Example 2, 48 " non-ionic emulsifier '(mixture of carboxylic acid polyglycol esters), 22 " water, mixed in the indicated order with stirring, gives a preparation which can be diluted with water, which is used in concentrations from 1-3% by weight, for example to make the dispersions fungicidal. 1. The reaction product of a dialkyltin compound with N-cyclohexyl-N'-hydroxy-diazenium oxide, characterized in that it has the general formula in which R is an alkyl residue with 1-12 carbon atoms, whereby the residues may be the same or different. 2. Dialkyltin compounds according to claim 1, characterized in that R is an n-alkyl radical with 3-8 carbon atoms. 3. Dialkyltin compounds according to claim 1, characterized in that R is an n-butyl. 4. Bactericidal and fungicidal agents, characterized in that, in addition to liquid or solid carrier substances, they contain one or more compounds according to claims 1-3 as active substance. 5. Wood finishing agent, characterized in that, in addition to liquid or solid carrier substances, it contains one or more compounds according to claims 1-3 as active substance. 6. Use of the agents according to claims 4 and 5 as a wood preservative, disinfectant, preservative for technical products and as a biocidal finish for textiles, plastics and building materials.