US2922738A - Fungicidal compositions - Google Patents

Description

locus of the fungi.

v cals.

FUNGICIDAL COMPOSITIONS No Drawing. Application May 27 1955 Serial No. 511,762

7 Claims. (Cl. 167- -22 This invention relates to fungicidal compositions and more particularly to new and potent tin-containing fungicidal compositions characterized by an essential lack of phytotoxicity'. This invention also relates to the use of such compositionsin combating fungi. I 2 An object of this invention is to provide new fungicidal compositions. A further object is to provide new fungicidal compositions coupling a high degree of fungitoxicity with an essential lack of phytotoxicity. Still another object is to provide a new means for combating fungi.

The above and other objects are accomplished by the present invention which resides in providing fungicidal compositions comprising a conditioning agent and as a principal active ingredient a material selected from the class consisting of diorganotin enolates, triorganotin enolates, diorganotin esters of phosphorus acids, triorganotin esters of phosphorus acids, diorganotin xanthates and triorganotin xanthates. A specific outstanding aspect of the invention resides in the provision of the fungicidal compositions comprising a conditioning agent and as a principal active ingredient a dialkyltin enolate, particularly dibutyltin diacetylacetonate.

We have found that such compositions are exceedingly useful in combating fungi when they are applied to the Such treatment, therefore, constitutes one aspect of our invention. We have found our materials to be especially useful in controlling and eliminating fungi which infest vegetation since the compounds completely lack phytoxicity, as nearly as can be I determined.

The active ingredients of this invention comprise or ganotin salts containing 2 to 3 organo groups directly attached to tin. Such organo groups are preferably hydrocarbon groups such as alkyl, aryl and alkenyl radi- However, they can also be substituted, as with halogen atoms. The alkyl groups have preferably 1-16 carbon atoms and the aryl groups 6-10 carbon atoms. The two or three organo groups in the molecule can be the same or they can be different. When different they can be selected from more than one of the above mentioned types of organo groups. That is to say, we provide dialkyltin salts, trialkyltin salts, diaryltin salts, triaryltin salts, alkylaryltin salts, dialkylaryltin salts, diarylalkyltin salts, etc. Thus we provide an active ingredient such as a trimethyltin salt, a dibutyltin salt, a methylpropylhexyltin salt, a dimethylbenzyltin salt, a diphenyltin salt, etc.

When our active ingredients is an enolate it can be in general prepared from any compound capableof existing in enol form. We find that especially good results are obtained when our active ingredient is derived from the enolic form of a ketone such as acetone, methylethylketone, dibutylketone, acetylacetone or acetonylacetone. That is, it can be prepared from monoketones and polyketones, especially diketones, particularly fi-diketones and u-diketones. Other enols which may be used to form our enolates include active methylene compounds, particularly those inwhich a methylene group is located be,-

United States Patent 2,922,738 Patented Jan. 26, i960 "ice acetylacetonate, didodecyltin diacetylacetonate, dibutyltin diacetylacetonate tributyltin acetylacetonate, .triphenyltin acetylacetonate, ethylditolyltin acetylacetonate, dibutyltin diacetonylacetonate, methyl-a-naphth'yltin 'diacetonylacetonate, diphenylhexyltin acetonylacetonate, di-

' acids, metaphosphoric acid and the like.

methylphenyltin acetonate, triisopropyltin methylethyl ketonate, diethylphenyltin cyclopentanonate, triethyltin ethylacetoacetate, methyldodecylhexyltin diethylm'alonate, and the like. Y

These compounds can readily be formed as for example by merely mixing the enolic compound and the dior triorganotin halide in alkaline solution 'such'as aqueous sodium hydroxide, aqueous sodium vcarbonate and even dilute aqueous ammonium hydroxidesolution, as is shown in the following example.

Example 1 Dibutyltin diacetylacetonate was prepared in good yield by merely mixing acetylacetone and dibutyltin dichloride in substantially 2:1 molar proportion for a period of a few minutes at room temperature in dilute ammonium hydroxide solution.

Likewise we prepare triphenyltin cyclohexanonate by reacting triphenyltin bromide with cyclohexanone" at room temperature in 2 percent aqueous sodium carbonate solution, etc.

When our active ingredient is an ester of a phosphorus acid it can be an ester of either a trivalent or a pentavalent phosphorus acid including phosphoric acid, phosphorus acid, pyrophosphoric acid, hypophosphorus'acid, primary and secondary phosphonous and phosphonic Furthermore the compound may be composed so that the phosphorus acid is either completely esterified with an organotin radical; partially esterified with an organotin radical and partially esterified with a hydrocarbon radical;or partially esterified with an organotin radical andhaving the remainder of its hydrogen atoms unesterified. Furthermore, any 'or all of the oxygen atoms in the phosphorus acid may be replaced with sulfur atoms so that our active ingredients encompass esters of thiophosphorus acids as well as their oxygenated analogs. I

Specific examples of our organotin esters of phosphorus acids include trimethyltin phosphite, triamyltin phosphite, tribenzyltin monohydrogenphosphite, di-

,hexyltolyltin dihydrogenphosphite, trilauryltin trithiophosphite, tri-fl-naphthyltin phosphate, ethyldiamyltin acids whose remaining free hydrogens are esterified with alkyl, cycloalkyl or aryl groups, are preferred v The phosphorus-containing materials of this invention may be prepared conveniently by condensing; a dior triorganotin halide with an alkali metal 101? other q as the conditioning agent.

metal solvent of the corresponding phosphorus acid as the following example illustrates.

, I i I V I Example 11 I V Di-butyltin (dimethylcyclohexyl .dithiophosphate) .,A mixture of 18.2 parts of dibutyltin dichloride and 432 --parts of potassium dimethylcyclohexyl, dithiophosphate in200 parts of petroleum ether was stirred at room Preparation of other phosphorus-containing materials of this invention can be effected in a similar way. Further examples of preparations of such materials can be found in. US. Patent 2,630,436. 'Similarly the xanthates of this invention can have as the xanth'ate portion'of the molecule a radical derived from any alkyl or aryl 'xanthat'e. Typical examples, of our xanthate ingredients include dibutyltin dimethylxanthate, dibutyltin dibutylxanthate, dimethyltin didodecyl- ,xanthate, triphenyltin methylxanthate, methyl diphenylmethylxanthate, methyltolyltin dioctylxanthate, di- -tolyltin diphenylxanthate and the like. Theymay be prepared conveniently by reaction of the dior triorganotin salt corresponding to the xanthate desired with the corresponding xanthate salt as the following example indicates. Our preferred xanthate ingredients are dialkyltin dialkylxanthates.

Example HI Dibutyltin dibutylxanthate.--To a stirred solution of 30.4 parts of dibutyltin dichloride in 320 parts of methanol was added a solution of 37.8 parts of potassium n-butylxanthate in 160 parts of methanol over a period of 1 hour with rapid agitation. An oil layer was then separated from the turbid solution and was withdrawn, filtered through a siliceous filter aid to remove the slight degree of turbidity which was present, following which the oily layer was heated at 100 to remove last traces of the alcohol solvent. The residue from this distillation was dibutyltin dibutylxanthate, a yellow viscous oil which was found by analysis to contain 19.3 percent sulfur and 19.4 percent tin.

The other xanthates of the present invention can be i made by similar methods. r

The conditioning agents with which we admix our active ingredients are of the type also known in the art as pest control adjuvants, extenders, and modifiers as well as dispersants, dispersing agents, surface-active agents, etc.

Their purpose is to extend the active ingredient to assure its eflicacious penetration or application onto the locus being treated and to adapt the active .ingredients for ready and efiicient application to pests and to the loci of the fungi using conventional equipment.

In general such formulations comprise both the liquid and solid types as well as the Aerosol type of formulation. The liquid type of formulation can have water, an organic solvent, an oil-Water emulsion and the like The liquid ingredient of the formulation may further contain a surface-active agent such as a detergent, a soap or other wetting agent. It is also intended that the term conditioning agent include solid carriers such as talc, pyrophyllite, Attaclay, kieselguhr, chalk, diatomaceous earth, and the like; and various mineral powders such as calcium carbonate and the like which act as a dispersant, as a carrier, and in' some 7 instances perform the function of a surface-active agent. I Among the preferred formulations employing solid conditioning agents are those known as wettable powders.

water dispersability to the compositions.

In general these wettable powders include the activeingredient, a surface-active agent and an inert carrier such as soybean flour, sulfur, calcium, mica, talc, humus and the like. In preparing such concentrated wettable powders it is preferred to employ between about 0.1 and 5 percent of the surface-active agent based upon the amount of active ingredient used and up to about percent of the inert solid carrier based upon the total amount of the formulation. Such formulations provide the advantage of permitting storage and transportation of the pesticides in readilyhandled form and permit further dilution by simple admixture with water to provide finished liquid formulations at the time of application.

Thus the formulations which comprise our active ingredient in combination with a conditioning agent provide liquid, solid and aerosol formulations in a form adapted to be readily applied to the material to be treated.

.The liquid compositions, either solutions or dispersions,

frequently contain a surface-active dispersing agent in amount suflicient to render the composition readily dispersable in water for aqueous spray application. The solid formulations also frequently contain a surfaceactive dispersing agent in amount suificient to impart When dust application is desired a surface-active dispersing agent can be omitted. In this case the formulation will still contain a solid carrier, extender or diluent as conditioning agent.

The surface-active dispersing agents referred to herein are sometimes known as wetting, dispersing or penetrating agents. They are agents which cause the formulations to be easily dispersed in water. They can be of the anionic, cationic or non-ionic type and include salts of long chain fatty acids, sulfonated oils-both vegetable and animalpetroleum oils, sulfates of long chain alcohols, phosphates of long chain alcohols, various polyethylene oxides and condensation products of ethylene oxide with alcohols and phenols, quaternary ammonium salts and the like. The surface-active agent will usually be present to the extent of 0.1 to 5 percent of the formulation.

The active ingredients can also be dispersed or suspended in various organic solvents such as alcohols, ketones, hydrocarbons, petroleum cuts such as kerosene, dimethylformamide and the like. In this case a surfaceactive dispersing agent is usually present to provide ready dispersability with water.

Typical of such formulations of this invention are described in the following examples in which all parts are parts by weight.

Example IV A formulation of dibutyltin diacetylacetonate is prepared by adding with vigorous agitation 10 parts of this material to 1000 parts of water containing one part of Tween-80. This concentrated dispersion is further diluted 1000 times by the addition of water to obtain a formulation of suitable concentration for application. Thus, the resulting dispersion contains 10 p.p.m. of our pesticide in the water dispersion.

The solubility of the active ingredients of this invention in organic solvents, furthermore, is such that it can be applied advantageously in the form of solution in this type of solvent, and for certain uses this method of application is preferred. For example, in treating cloth, leather, or other fibrous articles, it is preferred to apply the pesticides dissolved in a volatile solvent. Afteruse the volatile solvent evaporates, leaving the pesticidal agents, impregnated throughout the surface of the article and in thedispersed form which has been found to be most advantageous. Likewise, in applying the pesticides to. smooth surfaces, as, for example, in treating wood or other surfaces, .2. solution may be the most practical method for applying a protective film by brushing, spraying, or dipping. The choice of an appropriate solvent is determined largely by the concentration of active ingredient which it is desired to employ, by the volatility required in a solvent, the spreading or flow characteristics thereof, and by the nature of the material being treated.

' Example V A solution consisting of parts of tri-n-propyltin trithiophosphate in 250 parts of cyclohexanoneis prepared by stirring the two constituents for a period of 2 minutes at a temperature of about 25 C. This concentrated solution, suitable for storage or transportation, is further diluted with 99,750 parts of kerosene to form a final dilution of 50 p.p.m. suitable for application.

Example VI A mixture of 100 parts of dibutyltin dimethylxanthate, 1000 parts of Attaclay, and 0.1 part of Nacconol is intimately mixed in an L-shaped blender. The percent wettable powder thus prepared produces a satisfactory water suspension when 11 parts are stirred into 10,000 parts of water to produce a suspension containing 100 p.p.m. active ingredient.

Example VII Example VIII An oil-in-water emulsion is prepared by dissolving 10 parts of dibutyltin di(diphenyldithiophosphate) in 1000 parts of kerosene. This solution is dispersed with vigorous agitation in 99,000 parts of water containing 1 part of Triton X-100 to provide a dispersion containing 10 p.p.m. of active agent.

In addition, we have found that we can incorporate an adherent or sticking agent, such as vegetable oils, naturally occurring gums, and other adhesives, in our active ingredient formulations. Likewise, we can employ humectants in our formulations. Furthermore, these formulations can be employed in admixture with other pesticidal materials or other biocides, such as insecticides, larvicides, bactericides, vermicides, miticides, or with other materials which it is desired to apply along with our pesticides.

Our compounds also find effective use when formulated in Aerosol type formulations; that is, when mixed with a liquid of low boiling point that changes to a gas when released from a confined space. Examples of this type diluent are fluorinated hydrocarbons such as tetrafluoromethane and hexafluoroethane; mixed halogenated compounds containing fluorine and chlorine, such as difluorodichloromethane, pentafluorochloroethane; or ethylene substituted with both these halogens. Compounds containing fluorine and bromine are also applicable, as, for example, trifiuorobromomethane. Other materials such as carbon dioxide, sulfur dioxide, hydrogen sulfide, and ammonia can be used, and of these carbon dioxide is preferred. One method of preparing such Aerosol formulations comprises introducing our new compounds into a pressure cylinder and later introducing the liquefied diluent under pressure, followed by mixing the cylinder to obtain uniform solution. If desired, smaller containers can then be filled from the cylinder in which the formulation is made up. In many cases it is desirable to add a second solvent to the low boiling material of the type described above, so as to more readily dissolve our compounds. Examples of such cosolvents are benzene, acee tone, carbon tetrachloride, butyl acetate, Cellosolve, and the like.

Example IX Into a cylinder rated at 500 p.s.i. working pressure, is introduced 10 parts of triphenyltin phenylxanthate. The cylinder is then made pressure-tight except for one opening, through which is introduced a mixture of 50 parts acetone and 50 parts dichlorodifluoromethane from a container at 2000 p.s.i. The cylinder into which the in-' gredients are introduced is then sealed off and inverted to give a uniform Aerosol solution of our active materials in the mixture of cosolvents.

The fungicidal effectiveness of our compounds can be demonstrated by the following tests.

Tomato foliage disease test.--The tomato foliage disease test measures the percent control of early blight fungus, Alternaria solani, and late blight fungus, Phytophthora infestans. The chemicals are evaluated at concentrations of 2000 and 400 p.p.m. Chemicals showing good results at these concentrations are tested at successively lower concentrations to determine effective dosages. Tomato plants are sprayed with formulations of the active materials, allowed to dry and along with untreated controls are sprayed with a spore suspension of conidia of Alternaria solani or sporangia of Phytophthora infestans. The plants are held in a saturated atmosphere for 24 hours at 70 F. for early blight and 60 F. for late blight to permit spore germination and infection before removal to the greenhouse. After 2w 4 days lesion counts are made on the three uppermost fully expanded leaves. This test method is a modification of that described by McCallan and Wellman (Contrib. Boyce Thompson, 13(3) :93'134, July-September 1943).

In such tests the ED95 of typical compounds of this invention were found to be as follows:

ED-95 Against Early Blight ED-95 Against Blight Compound p.p.m.

p.p.m. Dibutyltin acetylacetonate Dibutyltin dimethylcyclohexylthiophosphate Dibutyltin dibutylxanthate Hoe NOIW

corn, variety Early Golden Orange; oats, variety Clydesdale; and tomato, variety Bonny Best. Phytotoxicity, at the end of 10 days, is rated on a scale from 0 to 11. The grades are based on the percent leaf area destroyed: 0=no injury; 1:0. to 3; 2:3 to 6; 3:6 to 12; 4=12 to 25; 5:25 to 50; 6:50 to 75; 7:75 to 87; 8:87 to 94; 9:94 to 97; 10:97 to 100; and at 11 the plant is dead. Other responses such as stunting, chlorosis, defoliation, and formative effects are noted. Chemicals which are rated 10 or more on one of the test plants are retested in dosage series to determine the level of their activity.

Tomato watering test-Potted tomato plants of the same variety as used in the foliage spray test are watered with 50 ml. of a one percent formulation of the test chemical. Plant effects are observed after ten days and are recorded as described in the foliage spray test.

In such tests the three compounds listed in the above table showed no phytotoxicity (phytotoxicity rating of 0) in each test with the exception that dibutyltin dimethylcyclohexylthiophosphate did show up to 3 percent injury (phytotoxicity rating of l) in the tomato soil watering test.

Similar fungitoxicity and phytotoxicity results are obtained with the other active ingredients of this invention.

ssl im 1. Method of combating fungi comprising treating the locus of the fungi with amaterial selected from the class consisting of diorganotin enolates, triorganotin enolates, diorganotin esters of phosphorus acids, triorganotin esters of phosphorus acids, diorganotin Xanthates, and triorganotin x anthates wherein said organo group is selected from the group consisting of alkyl groups having 1 to 6 carbon atoms and aryl groups having 6 to 10 carbon atoms and wherein said phosphorus acidis selected from the group consisting of phosphoric acid, phosphorus acid, pyrophosphoric acid, hypophosphorus acid, phosphonous acid, phosphonic acid, and metaphosphoric acid and wherein said enolate is selected from the group consisting of monoketones, u-diketones, fi-diketones, keto esters and active methylene compounds wherein a methylene radical is between two carboxylic groups, and wherein said Xanthate is selected from the group consisting of alkyl Xauthates and aryl Xanthates.

2, Method of combating fungi comprising treating the locus of the fungi with a material selected from the class consisting of dialkyltin p-keto ester enolate wherein the alkyl group has 1 to 16 carbon atoms.

3. Method of combating fungi comprising treating the locus of the fungi with dibutyltin diacetylacetonate.

, 4. Fungicidal composition comprising a dispersing agent as a Vfungicidaladjuvant and a surface-active agent and as a principal active ingredient a material selected from the class consisting of diorganotin enolates, triorganotin enolates, diorganotin esters of phosphorus acids, triorganotin esters of phosphorus acids, diorganotin xanthates, and triorganotin Xanthates wherein said organo group is selected from the group consisting of alkyl groups having 1 to 6 carbon atorns and aryl groups havacidtis 'selectedffi'om'the group consisting ,of phosphoric acid, phosphorus i'acidf pyrophosphorie'facid b passes; pho rus r.acid, phosphon'ous .acid, phosphonidacid, and metaphosphoric "and and wherein said enolate 'is selected from the group consistingof monoketones, 'a-diketones, fi-diketones, keto esters and active methylene compounds wherein a methylene radical is between two carboxylic groups, and wherein said xanthate is selected from the groupconsisting of alkyl xanthates and aryl xanthatcs.

5. A fungicidal composition comprising a dispersing agent as a fungicidal adjuvant and a surface-active agent and as a principal active ingredient a material selected from the group'consi'sting of a dialkyltin thiophosphate ester, a dialkyltin dialkyl xanthate, and a dialkyltin fiketo ester enolate wherein said alkyl groups have 1 to 16 carbon atoms. 7

6.'A fungicidal compositioncomprising adispersing agent as a fungicidal adjuvant and a surface-active agent and as a principal active ingredient a dialkyltin fl-keto ester enolate wherein the alkyl group has 1 to 16 carbon atoms..

7. A fungicidal composition comprising a dispersing agent as a fungicidal adjuvant and a surface-active agent and as a principal activeingredient dibutyltin diacetylacetonate.

References Cited in the file of this patent UNITED STATES PATENTS 1,736,448 Liebknecht Nov. 19, 1929 2,107,298 Kilgore: Feb. 8, 1938 2,150,759 Carter Mar. 14, 1939 2,278,965 Van Peski et a1. Apr. .7, 1942 2,702,777 Kerr et a1. Feb. 22, 1955

Claims (1)

1. METHOD OF COMBATING FUNGI COMPRISING TREATING THE LOCUS OF THE FUNGI WITH A MATERIAL SELECTED FROM THE CLASS CONSISTING OF DIORGANOTIN ENOLATES, TRIORGANOTIN ENOLATES, DIORGANOTIN ESTERS OF PHOSPHORUS ACIDS, TRIORGANOTIC ESTERS OF PHOSPHORUS ACIDS, DIORGANOTIN XANTHATES, AND TRIORGANOTIN XANTHATES WHEREIN SAID ORGANO GROUP IS SELECTED FROM THE GROUP CONSISTING OF ALKYL GROUPS HAVING 1 TO 6 CARBON ATOMS AND ARYL GROUPS HAVING 6 TO 10 CARBON ATOMS AND WHEREIN SAID PHOSPHORUS ACID IS SELECTED FROM THE GROUP CONSISTING OF PHOSPHORIC ACID, PHOSPHORUS ACID, PYROPHOSPHORIC ACID, HYPOPHOSPHORUS ACID, PHOSPHONOUS ACID, KPHOSPHONIC ACID, AND METAPHOSPHORIC ACID AND WHEREIN SAID ENOLATE IS SELECTED FROM THE GROUP CONSISTING OF MONOKETONES, A-DIKETONES, B-DIKETONES, KETO ESTERS AND ACTIVE METHYLENE COMPOUNDS WHEREIN A METHYLENE RADICAL IS BETWEEN TWO CARBOXYLIC GROUPS, AND WHEREIN SAID XANTHATE IS SELECTED FROM THE GROUP CONSISTING OF ALKYL XANTHATES AND ARYL XANTHATES.