EP0221083A1 - Haloalkyl triazolinones - Google Patents

Abstract

1-Aryl-1,2,4-triazolin-5 (1H)-herbicidal herons having a haloalkyl group (eg CHF2, CF3 or CClF2) linked to the carbon atom in position 3 of the triazolinone ring.

Description

HALOALKYL TRIAZOLINONES

This invention relates to herbicidal 1-aryl- 4,5-dihydro-1,2,4-triazol-5(1H)-ones having a haloalkyl group on the carbon at the 3-position of the triazolinone ring.

The herbicidal activity of certain 1-aryl-4,5-dihydro-1,2,4-triazol-5(1H)-ones (also known as 1-aryl-Δ²-1,2,4-triazolin-5-ones) having an alkyl group attached to the carbon at the 3-position of the heterocyclic ring has been described in the patent literature, as discussed below.

British published patent application 2,090,250 discloses herbicidal compounds of the formula

wherein R ¹ is an alkyl group, R² is an alkynyl group, a halomethyl group, or a haloethyl group and X is an alkoxy group, an alkenyloxy group, an alkoxyalkoxy group, an alkynyloxy group, a hydroxy group, a halomethyloxy group, or a haloethyloxy group.

Japanese Kokai 107975 discloses herbicidal compounds of the formula

(R₁ is 1-4C alkyl; R₂ is H, 1-4C alkyl, halomethyl or 3-4C alkynyl; X is Cl or F; Y is Cl, Br, OH or OR₃; R₃ is 1-4C alkyl or benzyl; Z is H, carboxy, cyanomethoxy, COOR₄, COSR₅ or CON(R ⁶) (R⁷);

R₄ is 1-4C alkyl or 3-4C alkoxyalkyl; R₅ is 1-4C alkyl; and R₆ and R₇ are H, 1-4C alkyl or alkoxy).

U.S. patent 4,318,731 discloses herbicidal compounds of the formula

wherein R ¹ is C₁-C₄ alkyl; R² is hydrogen, C₁ -C₆ alkyl or C₁-C₄ alkenyl; and X is hydroxy, C₁-C₄ alkyl,

C₁-C₆ alkyloxy, an alkyloxyalkyloxy of which two alkyls may be the same or different and each alkyl is

C₁-C₄, a C₂-C₄ alkenyloxy, or an alkyloxycarbonylalkyloxy of which two alkyls may be the same or different and each alkyl is C₁-C₄.

Also, U.S. patent 4,404,019 discloses herbicidal compounds of the formula

wherein R is a C₁-C₄ alkyl group, a C₃-C₄ alkenyl group or a C₃-C₄ cycloalkyl group, X is a chlorine or bromine atom and Y is a hydrogen atom or a C₁-C₄ alkoxy group.

The compounds of this invention are herbicidal aryl-4,5-dihydro-1,2,4-triazol-5(1H)-ones (such as those in the prior art, e.g. described above) in which, however, the carbon atom at the 3-position of the triazole ring carries a C₁-C₄ haloalkyl group whose halogens are selected from F, Cl and Br, particularly a fluoroalkyl (e.g. difluoromethyl) group.

The compounds of the invention are those which have the following formula:

where R² is said haloalkyl group and R¹ may be hydrogen, but preferably is alkyl (e.g. of 1 to 6, preferably 1 to 4, carbon atoms); haloalkyl (e.g. of 1 to 5, preferably 1 to 3, carbon atoms particularly fluoroalkyl); cyanoalkyl (e.g. of 2 to 5 carbon atoms, for example, cyanomethyl); alkenyl (e.g. of 2 to 5 carbon atoms such as 2-propenyl); alkynyl (e.g. of 2 to 5 carbon atoms such as 2-propynyl); alkoxyalkyl

(e.g. of 2 to 8 carbon atoms, for example, 2-methoxyethyl); amino; alkylamino (e.g. of 1 to 6 carbon atoms); alkoxy (e.g. of 1 to 6, preferably 1 to 4, carbon atoms); haloalkenyl or haloalkynyl; or alkylthioalkyl (e.g. of 2 to 8 carbon atoms, for example

2-methylthioethyl) or the corresponding alkylsulfinyl alkyl or alkylsulfonylalkyl groups (having, respectively 1 or 2 oxygen atoms on the S atom); and Ar is an aryl radical. Ar is further defined by the limitation that the 3-Methyl-4-Difluoromethyl Analogs of the compounds of this invention are herbicides, said Analogs being compounds which are otherwise identical to compounds of this invention except that said Analogs have, at the 3- and 4-positions of the 4,5-dihydrotriazol-(1H)-ring, a CH₃ and a CHF₂ substituent, respectively. The aryl radical thus represents a group useful in the 1-aryl-4, 5-dihydro-1,2,4-triazol-5(lH)-one art to give herbicidal compounds when attached at the 1-position of an appropriate known 4,5-dihdyro-1,2,4-triazol-5(1H)-one. For instance any of the aryl radicals of the aforementioned patents may be used.

The Ar radical is preferably such that said 3-Methyl-4-Difluoromethyl Analog has marked herbicidal properties. For instance, the 3-Methyl-4-Difluoromethyl Analogs of the preferred compounds show at least 50% kill of at least one of the following species of plants when applied under at least one of the following modes at the rate of 0.5 kg/ha, and more preferably show such kill of at least 50% when applied at the rate of 0.1 kg/ha: Species: velvetleaf (Abutilon theophrasti), green foxtail (Setaria viridis); Modes: pre-emergent, post-emergent. Testing for such herbicidal activity may be carried out in the manner described below (under the heading "Herbicidal Activity").

Ar is preferably a ring-substituted aryl radical. For instance it may have a benzene ring such as the radical indicated by the following formula

wherein X¹ may be for instance hydrogen or halogen, preferably fluorine or chlorine, the halogen atom advantageously being positioned at the C-2 carbon atom of the phenyl ring;

X² may be hydrogen, halogen such as fluorine, chlorine, or bromine, alkyl of 1 to 6 (preferably 1 to 4) carbon atoms, particularly methyl, haloalkyl of 1 to 5 carbon atoms, for example, trifluoromethyl, alkoxy of 1 to 6 (preferably 1 to 4) carbon atoms;

Z may, for instance, be hydrogen; halogen such as fluorine, chlorine, or bromine; alkyl of 1 to 6 (preferably 1 to 4) carbon atoms; cyanoalkyl; haloalkyl of 1 to 5 carbon atoms; nitro; a group -OR; or a group -CO-R⁶ or CH₂CO-R⁶ or CH( CH₃)CO-R⁶; or a group -OSO-R⁹;

R may be hydrogen, alkyl of 1 to 6 (preferably 1 to 4) carbon atoms which may be substituted with cycloalkyl of 3 to 7 carbon atoms (for example, methyl or 1-methylethyl, or cyclohexylmethyl), cycloalkyl of 3 to 7 carbon atoms which may be substituted with alkyl of 1 to 6 carbon atoms (for example, cyclopentyl or methylcyclopropyl), alkoxyalkyl of 2 to 8 carbon atoms (for example, ethoxymethyl), cyanoalkyl of 2 to 7 carbon atoms such as cyanomethyl or 2-cyanoethyl, alkenyl of 2 to 5 carbon atoms such as 2-propenyl, alkynyl of 2 to 5 carbon atoms such as 2-propynyl, haloalkyl of 1 to 5 (preferably 1 to 3) carbon atoms especially a fluoroalkyl, haloalkenyl of 2 to 5 carbon atoms, haloalkynyl of 2 to 5 carbon atoms such as 3-bromo-2-propynyl, alkylsulfonyl of 1 to 6 (preferably 1 to 4) carbon atoms (wherein the alkyl moiety may be substituted with halogen, especially fluorine or chlorine, cyano, alkoxy or alkylthio of 1 to 4 carbon atoms such as methoxy or methylthio, or alkylamino or dialkylamino in which each alkyl is of 1 to 4 carbon atoms), alkylaminosulfonyl or dialkylaminosulfonyl wherein each alkyl is of 1 to 4 carbon atoms, arylsulfonyl such as phenylsulfonyl, alkylcarbonyl of 2 to 7 carbon atoms such as acetyl, or a 5- or 6-membered ring heterocyclic group of 1 or 2 same or different heteroatoms selected from O, S (including the S-oxide and S-dioxide), and N or an alkyl radical of 1 to 5 (preferably 1. to 3) carbon atoms substituted with said heterocyclic group. R may also be a group

-CR³R⁴(CH ) -CO-Q¹-R⁵ in which n is 0 to 2 (preferably 0); R³ and R⁴ may be independently hydrogen or alkyl or alkoxy of 1 to 4 carbon atoms, Q¹ is O, S or NR ⁷ wherein R⁷ may be H or alkyl of 1 to 6

(preferably 1 to 4) carbon atoms and R⁵ may be hydrogen, alkyl of 1 to 6 (preferably 1 to 4) carbon atoms, alkoxyalkyl or alkylthioalkyl of 2 to 6 carbon atoms, haloalkyl of 1 to 5 carbon atoms (especially fluoroalkyl or chloroalkyl), alkenyl of 2 to 5 carbon atoms such as 2-propenyl, cycloalkenyl of 5 to 7 carbon atoms which may be substituted with alkyl of 1 to 4 carbon atoms (for example, 2-cyclohexenyl), cyclohexenylalkyl of 6 to 10 carbon atoms (for example, 3-cyclohexenylmethyl), phenyl or benzyl (which may be ring-substituted with fluorine, chlorine, bromine, or alkyl, alkoxy, or alkylthio of 1 to 4 carbon atoms), cyanoalkyl of 2 to 7 carbon atoms such as cyanomethyl, alkynyl of 2 to 5 carbon atoms such as 2-propynyl, alkylideneamino of 1 to 6 (preferably 1 to 4) carbon atoms which may be substituted with cycloalkyl 3 to 7 carbon atoms, cycloalkylideneamino of 5 to 7 carbon atoms which may be substituted with alkyl of 1 to 4 carbon atoms. When Q¹ is NR ⁷ , R⁵ may additionally be alkoxy, alkylthio, or alkylsulfonyl, each of 1 to 6 carbon atoms, phenylsulfonyl, or phenylalkylsulfonyl of 1 to 3 alkyl carbon atom.

As indicated above, R of the -OR substituent may be a heterocyclic group or an alkyl radical substituted with a heterocyclic group. The R group of this type may be any of those disclosed in my copending application Serial No. 655,960, filed September 28, 1984, and its parent application Serial No. 541,596, filed October 13, 1983, which disclose aryltriazolinones whose aryl groups have such -OR substituents (the present application is a continuation-in-part of both those applications and incorporates, by reference, their entire disclosures.) The "Ar" radical of this invention may be any of the aryl radicals disclosed in those applications. Among the R groups, on those aryl radicals, which may be employed are 1-methyl-3-pyrrolidinyl, furfuryl or 2-thienylmethyl, or preferably 3-tetrahydrofuranyl, tetrahydrofurfuryl, tetrahydropyran-2-ylmethyl, 1,3-dioxolan-2-ylmethyl, 2-(1,3-dioxolan-2-yl)ethyl, 2 ,2-dimethyl-1,3-dioxolan-4-yl-methyl, 3-(2-methyl-1,3-dioxolan-2-yl)propyl, 1,3-dioxan-4-ylmethyl, 1,4-benzodioxan-2-ylmethyl, tetrahydro-4H-pyran-4-yl, 5,6-dihydro-2H-pyran-3-ylmethyl, 2,2-dimethyl-1,3-dithiolan-4-ylmethyl, tetrahydro-4Hthiopyran-4-yl, tetrahydrothien-3-yl, 1-oxotetrahydrothien-3-yl, 1,1-dioxotetrahydrothien-3-yl, 2,2-2imethyl-1,1,3,3-tetraoxo-1,3-dithiolan-4-ylmethyl, 1,4-dithiacycloheptan-6-yl, 1,4-dithiacyclohept-5- ene-6-yl, tetrahydro-4H-pyran-3-yl, glycidyl, 2,3-epithiopropyl, 2,2-bis(chlorodifluoromethyl)-1,3-dioxolan-4-ylmethyl, or 1,1-dioxotetrahydro-4H-thiopyran-4-yl. As indicated above, Z may be a group -CO-R⁶,

-CH₂CO-R⁶ or -CH(CH₃)CO-R⁶ where R⁶ is hydroxy, alkoxy or alkylthio of 1 to 6 carbon atoms such as methoxy or methylthio, alkoxyalkoxy of 2 to 6 carbon atoms (for example, 2-methoxyethoxy), amino, or alkylamino or dialkylamino wherein each alkyl is of 1 to 6 (preferably 1 to 4) carbon atoms and may be substituted with alkoxy of 1 to 4 carbon atoms (for example, methylamino, dimethylamino, or (methyl) (2-methoxy- ethyl) amino).

As indicated above R of the -OR substituent may be a group -CR³R⁴ (CH₂) COQ¹-R⁵. Aryl triazolmones whose aryl radicals have such -OR substituents of this type are disclosed in my copending application Serial No. 666,933 filed October 31, 1984. (The present application is a continuation-in-part of that application, whose entire disclosure is incorporated herein by reference.) The "Ar" radical of this invention may be any of the aryl radicals disclosed in that copending application. As indicated above Z may also be a group -OSO₂R⁹ where R⁹ is alkyl, haloalkyl, cyanoalkyl, arylalkyl, cyclic alkyl, alkenyl, haloalkenyl, arylalkenyl, alkynyl, haloalkynyl, arylalkynyl, aryl, or a group of the formula -(CH₂)_mNR^3' R^4' or -alkyl-Y-R^5' wherein m is 0 to 5; R^3' is hydrogen or alkyl; R^4' is alkyl or a group of the formula -alkyl-Y^3' -R^8'; R^8' is alkyl, alkoxycarbonylalkyl, alkenyl, or alkynyl; and Y ^3' is oxygen or S(O)_r in which r is 0 to 2. My copending application Serial No. 650,755 filed September 13,

1984 and its parent application Serial No. 533,013 filed September 15, 1983 (of both of which this application is a continuation-in-part, the entire disclosure of said copending applications being incorporated herein by reference) disclose aryl triazolinones whose aryl groups have a 5-substituent designated in said applications as "-OSO₂R". The "Ar" radical of this invention may be any of the aryl radicals disclosed in those applications. Among the -OSO₂R⁹ groups, on those aryl radicals, which may be used are those in which R⁹ is methyl, ethyl, propyl, 1-methylethyl, butyl, 2-methylpropyl, 1-methylpropyl, 3-methylbutyl, chloromethyl, dichloromethyl, 3-chloropropyl, bromomethyl, difluoromethyl, trifluoromethyl, cyanomethyl, benzyl, cyclopropyl, 2-propenyl, 2,3,3-trichloro-2-propenyl, 2-propynyl, 3-bromo-2-propynyl, dimethylamino, dimethylaminoethyl, 2-methoxyethyl, 2-ethoxyethyl, 2-(2-propenoxy)ethyl, 2-(2-propenthio)ethyl,

2-(2-propynoxy)ethyl, 2-(methoxycarbonylmethoxy)ethyl, and 2-(methoxycarbonylmethylthio)ethyl.

Frequently, the aryl radical will be a dihalophenyl radical, preferably a 2,4-dihalophenyl radical, for example, a 5-(alkoxy or alkynyloxy of up to 6 carbon atoms) -2,4-dihalophenyl radical such as a 4-chloro-2-fluoro-5-(1-methylethoxy)phenyl or 4-chloro-2-fluoro-5-(2-propynyloxy)phenyl radical.

It will be understood that any alkyl, alkenyl or alkynyl groups of the compound may be straight chain or branched chain radicals. Thus, 1-methylethyl, 2-methyl-2-propenyl, and 1-methyl-2-propynyl are branched chain examples of alkyl, alkenyl, and alkynyl radicals respectively. The halogen may be fluorine, chlorine, bromine or iodine. The haloalkyl radical may have one or more same or different halogen atoms.

Included in the genus above are compounds in which Z is hydroxy, which, while generally herbicidal at high application rates, are more useful as intermediates than as herbicides. As useful intermediates in the preparation of the more herbicidally active members of the genus, such compounds form a preferred embodiment of the invention.

With respect to herbicidal properties, in the embodiments presently of most interest, the substituents X ¹ and X² are preferably both halogen, with

X ¹ being fluorine or chlori.ne and X² being chlorine or bromine. The X¹ halogen will usually be positioned at the C-2 carbon atom of the phenyl ring. The compounds wherein X¹ is fluorine are particularly preferred.

The present compounds may be prepared by methods described in the literature or by methods analogous and similar thereto and within the skill of the art.

To make the compounds of .the present invention in which R ² is CHF₂, it is particularly convenient to start with CHF₂COOH, by converting the latter into an ester of difluoroacetylcarbamic acid (e.g. an ester of the formula CHF₂-CO-NHCO-O-lower alkyl), as by first converting the starting material into its acid chloride (e.g. by reaction with SOCl₂) and then reacting the latter with a lower alkyl urethane of the formula NH₂CO-O-lower alkyl as illustrated in Step A of Example 1, below.

The ester of difluoroacetylcarbamic acid may then be converted into a 1-aryl-4,5-dihydro-3-difluoromethyl-1,2,4-triazol-5(1H)-one by reacting it with an aryl hydrazine, as illustrated in Step B of Example 1. The aryl group of that hydrazine may carry all the substituents desired in the final compound (as is the case in the process for making compound 10 described at the end of Step B of Example 1) or those substituents, and any R¹ substituent, may be added in subsequent reactions, as illustrated in Steps C, D, E, F and G of Example 1. One or both of the (halogen) substituents at the 2- and/or 4-position of the phenyl group may be introduced subsequently, e.g. by halogenating (as with SO₂Cl₂) a 1-aryl-4,5-dihydro-3-difluoromethyl-4-methyl-1,2,4-triazol-5(1H)-one having hydrogen at one of those 2- and/or 4-positions and having any appropriate group at the 5-position of the phenyl group.

Instead of the alkyl difluoroacetylcarbamate one may use a haloacetonitrile (such as F₂HC-CN or F₃C-CN or F₂ClC-CN) for reaction with the aryl hydrazine (as illustrated in Step A of Example 2, below) to form the polyhaloacetamidine, which may then be reacted with phosgene to form a 1-aryl-4,5-dihydro-3-polyhalomethyl-4,5-dihydro-1,2,4-triazol-5(1H)-one(as illustrated in Step B of Example 2). Subsequent reactions may add an R¹ substituent at the 4-position of the 4,5-dihydro-1,2,4-triazol ring (as in Step C of Example 2) and/or vary the substituents on the aryl radical.

In these synthesis methods (e.g. the particular routes described above and in the Examples) there are formed useful intermediates which are 1-aryl-4,5-dihydro-1,2,4-triazol-5(1H)-ones having H on the nitrogen at the 4-position of the 4,5-dihydrotriazol ring and haloalkyl of 1 to 4 carbon atoms (e.g. CHF₂, CF₃ or CClF₂) on the carbon at the 3-position of that ring. (It will be understood that these compounds may also exist in their tantomeric forms as 1-aryl-1,2-dihydro-1,2,4-triazol-5(1H)-ones having hydrogen on the nitrogen at the 2-position. The 1-aryl group of such an intermediate may be a substituted phenyl radical identical with that present in the final compound or it may be a substituted phenyl radical containing an easily replaceable substituent (e.g., a methoxy group at the 5-position of the phenyl radical, as in a 5-methoxy-4-chloro(or bromo)-2-fluorophenyl radical) which phenyl radical can then be converted, by replacing that substituent, to the final substituted phenyl radical, preferably after first converting it to the corresponding phenolic radical (e.g. a 5-hydroxyphenyl radical). When the aryl group is to have a 2-F substituent it is preferred that the F substituent be present before formation of the heterocyclic ring, e.g. by using a fluorophenyl hydrazine as the reactant.

Some representative compounds of this invention are identified in the following table.

The following Examples illustrate the preparation of the compounds of this invention.

Example 1

N-(2-CHLOROPHENYLSULFONYL) 1-[2-CHLORO-4-FLUORO- 5-(3-DIFLUOROMETHYL-4,5-DIHYDRO-4-METHYL-5-OXO- 1H-1,2,4-TRIAZOL-1-YL)PHENOXY]PROPIONAMIDE

Step A Ethyl difluoroacetylcarbamate

During a thirty minute period 65.4 g (0.55 mole) of thionyl chloride was added dropwise to 50.0 g (0.52 mole) of difluoroacetic acid with stirring, while maintaining a reaction temperature of 20-25°C. After complete addition the mixture was stirred at room temperature for 1.5 hours and 46.4 g (0.52 mole) of urethane was added. The resultant mixture was heated at reflux for approximately three hours then allo.wed to cool to room temperature and stir for approximately 18 hours. The reaction mixture was again heated at 77°C for two hours. Unreacted materials were removed from the reaction mixture by evaporation under reduced pressure leaving 81.1 g of ethyl difluoroacetylcarbamate as a semi-solid residue.

The nmr spectrum was consistent with the proposed structure.

Step B 1-(4-Chloro-2-fluoro-5-methoxyphenyl)-3- difluoromethyl-4,5-dihydro-1,2,4-triazol- 5(1H)-one To a stirred mixture of 8.0 g (0.042 mole) of 4-chloro-2-fluoro-5-methoxyphenylhydrazine and 8.4 g (0.05 mole) of ethyl difluoroacetylcarbamate in 120 mL of xylene was added 2.1 g of phosphorus pentoxide. After complete addition the mixture was heated at reflux for one hour. While still hot, the reaction mixture was decanted from a dark residue into a clean flask. This residue was washed with xylene and the wash was combined with the decanted reaction mixture. The resultant mixture was stirred at room temperature for one hour. A precipitate formed and was removed by filtration and saved for later purification. The filtrate was extracted with three 150 mL portions of an aqueous 10% sodium hydroxide solution. The basic washes were combined and extracted with xylene. During the extraction an oil formed a third phase in the bottom of the separatory funnel and was removed from the other two phases. The basic aqueous phase was separated from the organic phase and filtered through a celite pad. The filtrate was washed with two portions of diethyl ether and acidified with concentrated hydrochloric acid. The acidified aqueous mixture was stirred at room temperature forming a brown precipitate. Collection of the precipitate by filtration yielded 1.5 g of 1-(4-chloro-2-fluoro-5-methoxyphenyl)-3-difluoromethyl-4,5-dihydro-1,2,4-triazol-5(1H)-one. The precipitate which was previously saved for purification was stirred in 70 mL of an aqueous 10% sodium hydroxide solution. The basic mixture was filtered through a celite pad to remove insoluble materials. The filtrate was acidified with concentrated hydrochloric acid producing a white solid. This solid was collected by filtration to yield an additional 0.7 g of product (mp 188-190°C).

The nmr spectrum was consistent with the proposed structure.

Compound 10, 1-[2,4-dichloro-5-(1-methylethoxy)-phenyl]-3-difluoromethyl-4,5-dihydro-1,2,4-triazol-5(lH)-one, and 1-(3-methoxyphenyl)-3-difluoromethyl-4,5-dihydro-1,2,4-triazol-5(1H)-one were prepared by the method of Example 1, Step B, from 2,4-dichloro- 5-(1-methylethoxy)phenylhydrazine or 3-methoxyphenylhydrazine, respectively.

Step C 1-(4-chloro-2-fluoro-5-methoxyphenyl)- 3-difluoromethyl-4,5-dihydro-4-methyl- 1,2,4-triazol-5(1H)-one

A stirred mixture of 2.0 g (0.0067 mole) of 1-(4-chloro-2-fluoro-5-methoxyphenyl)-3-difluoromethyl-4,5-dihydro-1,2,4-triazol-5(1H)-one and 2.1 g (0.015 mole) of potassium carbonate in 50 mL of acetone was heated at reflux for 30 minutes forming a thick slurry. Iodomethane (4.3 g, 0.03 mole) was added in one portion to the refluxing reaction mixture. After complete addition the mixture was stirred at reflux for 45 minutes. The mixture was cooled to room temperature and the solvent evaporated under reduced pressure leaving a solid residue. This residue was partitioned between water and methylene chloride. The two phase mixture was filtered through a celite pad. The organic phase was removed and was washed in succession with four portions of an aqueous 10% sodium hydroxide solution, and one portion each of an aqueous 10% hydrochloric acid solution, a saturated aqueous sodium carbonate solution, and water. After washing, the organic phase was dried over anhydrous magnesium sulfate and filtered. The filtrate was evaporated under reduced pressure to yield 1.6 g of 1-(4-chloro-2-fluoro-5-methoxyphenyl)-3-difluoromethyl-4,5-dihydro-4-methyl-1,2,4-triazol-5(1H)-one. A portion of this material was recrystallized from ethanol and water to provide the product as a light tan solid (mp 127-129°C), Compound 22.

The nmr spectrum was consistent with the proposed structure. Analysis calcd for

C₁₁H₉ClF₃N₃O₂: C 42.94; H 2.95; N 13.66; Found: C 42.74; H 3.15; N 13.35.

The following compounds were also prepared by the process of Example 1, Step C, from 1-(4-chloro-2-fluoro-5-methoxy-phenyl-3-difluoromethyl-4,5-dihydro-1,2,4-triazol-5(1H)-one; 1-(2,4-dichloro-5-methoxyphenyl)-3-difluoromethyl-4,5-dihydro-1,2,4+triazol-5(1H)-one; or 1-(3-methoxyphenyl)-3-difluoromethyl-4,5-dihydro-1,2,4-triazol-5(1H)-one and one of the following:

Compound Reagent

4 iodomethane

6 iodomethane

11 iodomethane

12 allyl bromide 27 iodoethane

33 chloromethyl methyl ether

Compounds which contain a 4-difluoromethyl group (i.e. Compounds 3 and 5) may be prepared by a process analogous to Example 1, Step C, by reacting 1-(3-methoxyphenyl)-3-difluoromethyl-4,5-dihydro-1,2,4-triazol-5(1H)-one or 1-(2,4-dichloro-5-methoxyphenyl)-3-difluoromethyl-4,5-dihydro-1,2,4-triazol-5(1H)-one first with sodium hydroxide and tetrabutylammonium bromide in cyclohexane and tetrahydrofuran followed by chlorodifluoromethane.

Step D 1-(4-Chloro-2-fluoro-5-hydroxyphenyl)- 3-difluoromethyl-4,5-dihydro-4-methyl- 1,2,4-triazol-5(1H)-one

To a stirred ice cold solution of 1.5 g (0.0048 mole) of 1-(4-chloro-2-fluoro-5-methoxyphenyl)-3-difluoromethyl-4,5-dihydro-4-methyl-1,2,4-triazol-5(lH)-one in 80 mL of methylene chloride was added dropwise 14.2 mL of a 1 M solution of boron tribromide in methylene chloride. After complete addition the mixture was allowed to warm to room temperature and stir for approximately 18 hours. The mixture was poured into ice water and the resultant mixture stirred until the ice had melted. The organic phase was separated from the mixture and was washed with two portions of water. After washing, the organic phase was dried over anhydrous magnesium sulfate and filtered. Evaporation of the filtrate under reduced pressure yielded 1.2 g of 1-(4-chloro-2-fluoro-5-hydroxyphenyl)-3-difluoromethy1-4, 5-dihydro-4-methyl-1,2,4-triazol-5(1H)-one (mp 153-155°C), Compound 23.

The nmr spectrum was consistent with the proposed structure.

Compounds 1, 2, 28 and 38 were prepared by the process disclosed in Example 1, Step D, from the corresponding 1-(2-halo-4-chloro-5-alkoxyphenyl)-1,2,4-triazol-5(1H)-one.

Step E tert-Butyl 2-[2-chloro-4-fluoro-5-(3- difluoromethyl-4,5-dihydro-4-methyl-5-oxo- 1H-1,2,4-triazol-l-yl)phenoxy]propionate

A mixture of 0.7 g (0.0023 mole) of 1-(4-chloro-2-fluoro-5-hydroxyphenyl)-3-difluoromethyl-4, 5-dihydro-4-methyl-1,2,4-triazol-5(1H)-one, 0.9 g (0.0067 mole) of potassium carbonate, and 0.6 g (0.0027 mole) of tert-butyl 2-bromopropionate in 40 mL of acetone was stirred at room temperature for approximately 72 hours. The reaction mixture was partitioned between water and methylene chloride and the organic phase was washed with water. After drying over anhydrous magnesium sulfate the organic phase was filtered. Evaporation of the filtrate under reduced pressure yielded 0.9 g of tert-butyl 2-[2-chloro-4-fluoro-5-(3-difluoromethyl-4, 5-dihydro-4-methyl-5-oxo-1H-1,2,4-triazol-1-yl)phenoxy]propionate as an oil, Compound 40.

The nmr spectrum was consistent with the proposed structure.

The following compounds were also prepared by the process of Example 1, Step E, from 1-(2,4-dichloro-5-hydroxyphenyl)-3-difluoromethyl-4, 5-dihydro-4-methyl-1,2,4-triazol-5(1H)-one, Compound 2; 1-(4-chloro-2-fluoro-5-hydroxyphenyl)-3-difluoromethyl-4, 5-dihydro-4-methyl-1,2,4-triazol-5(1H)-one, Compound 23; 1-(2,4-dichloro-5-hydroxyphenyl)-3-chlorodifluoromethyl-4, 5-dihydro-4-methyl-1,2,4-triazol-5(1H)-one; 1-(2,4-dichloro-5-hydroxyρhenyl)-3-trifluoromethy1-4, 5-dihydro-4-methyl-1,2,4-triazol-5(1H)-one, Compound 38; 1-(2,4-dichloro-5-hydroxyphenyl)-4-ethyl-3-difluoromethyl-4, 5-dihydro-1,2,4-triazol-5(1H)-one, Compound 28; 1-(2,4-dichloro-5-hydroxyphenyl)-3-difluoromethyl-4, 5-dihydro-4-(2-propenyl)-1,2,4-triazol-5(1H)-one; or 1-(2,4-dichloro-5-hydroxyphenyl)-4-cyanomethyl-3-difluoromethyl-4, 5-dihydro-1,2,4-triazol-5(1H)-one and one of the following:

Compound Reagent

7 propargyl bromide

8 propargyl bromide 13 propargyl bromide 16 methyl bromoacetate 17 bromo acetonitrile 18 iodoacetamide 20 propargyl bromide 21 ethyl 2-bromopropionate 25 propargyl bromide 29 propargyl bromide 32 chloromethyl methyl ether 34 propargyl bromide 37 propargyl bromide

In addition, the following compounds were prepared in a manner analogous to Example 1, Step E, replacing potassium carbonate and acetone with sodium hydride and N,N-dimethylformamide, from one of the 1,2,4-triazol-5(1H)-one intermediates listed above and one of the following:

Compound Reagent 9 3-tetrahydrofuryl 4-methylbenzenesulfonate

14 ethyl 2-bromopropionate 15 ethyl 2-bromopropionate 19 3-tetrahydrofuryl 4-methylbenzenesulfonate

26 ethyl 2-bromopropionate

Step F 2-[2-Chloro-4-fluoro-5-(3-difluoromethyl- 4,5-dihydro-4-methyl-5-oxo-1H-1,2,4-triazol- 1-yl)phenoxy]propionic acid A mixture of 0.8 g (0.002 mole) of tert-butyl 2-[2-chloro-4-fluoro-5-(3-difluoromethyl-4,5-dihydro-4-methyl-5-oxo-1H-1,2,4-triazol-1-yl)phenoxy]propionate and 59.2 g (0.52 mole) of trifluoroacetic acid was stirred at room temperature for two hours. Most of the trifluoroacetic acid was removed from the mixture by distillation under reduced pressure leaving a residue. This residue was partitioned between methylene chloride and water. The organic phase was dried over anhydrous magnesium sulfate and filtered. The filtrate was evaporated under reduced pressure to yield 0.5 g of 2-[2-chloro-4-fluoro-5-(3-difluoromethyl-4, 5-dihydro-4-methyl-5-oxo-1H-1,2,4-triazol-1-yl)phenoxy]propionic acid as an oil.

The nmr was consistent with the proposed structure.

Step G N-(2-Chlorophenylsulfonyl)^∙2-[2-chloro- 4-fluoro-5-(3-difluoromethyl-4, 5-dihydro- 4-methyl-5-oxo-1H-1,2,4-triazol-l-yl)- phenoxy]propionamide]

A stirred mixture of 0.4 g (0.0011 mole) of 2-[2-chloro-4-fluoro-5-(3-difluoromethyl-4, 5-dihydro-4-methyl-5-oxo-1H-1,2,4-triazol-1-yl)phenoxy]propionic acid, 0.2 g (0.0011 mole) of 2-chlorophenylsulfonyl isocyanate and a catalytic amount (0.03 g) of 4-dimethylaminopyridine in 40 mL of toluene was heated at reflux for approximately 18 hours. The mixture was cooled and evaporated under reduced pressure to yield 0.5 g of N-(2-chlorophenylsulfonyl) 2-[2-chloro-4-fluoro-5-(3-difluoromethyl-4,5-dihydro-4-methyl-5-oxo-1H-1,2,4-triazol-1-ly)phenoxy]propionamide as a solid (mp 162-166°C), Compound 39.

The nmr spectrum was consistent with the proposed structure. Example 2 1-[2,4-DICHLORO-5-(1-METHYLETHOXY)PHENYL]- 3-TRIFLUOROMETHYL-4, 5-DIHYDRO-4-METHYL- 1,2,4-TRIAZOL-5(1H)-ONE

Step A N-[2,4-Dichloro-5-(l-methylethoxy)anilino]- trifluoroacetamidine

Under a dry nitrogen atmosphere a stirred solution of 2.4 g (0.01 mole) of 2,4-dichloro-5-(1-methylethoxy)phenylhydrazine in 140 mL of methanol was cooled to -60ºC in a dry ice-isopropanol bath. Trifluoroacetonitrile (23.2 g, 0.24 mole) was bubbled into the cold solution during a two minute period. After complete addition the cold solution was stirred for 30 minutes, then allowed to warm slowly to room temperature during the next three hours. A stream of nitrogen gas was bubbled into the room temperature solution to aid in the vaporization and removal of trifluoroacetonitrile, leaving a liquid residue. This residue was evaporated further under reduced pressure to leave a resinous material. This material was stirred in cold pentane to produce a solid. The pentane was decanted and the solid triturated in fresh cold pentane. The pentane was decanted and the solid dried under reduced pressure to yield 2.9 g of N-[2,4-dichloro-5-(1-methylethoxy)anilino]trifluoroacetamidine (mp 80.5-81°C).

The nmr spectrum was consistent with the proposed structure.

In addition to the above intermediate, N-[2,4-dichloro-5-(1-methylethoxy)anilino]chlorodifluoroacetamidine and N-(4-chloro-2-fluoro-5-methoxyanilino)chlorodifluoroacetamidine were prepared by the process described in Example 2, Step A, from the correspond ingly substituted phenylhydrazine and chlorodifluoroacetonitrile.

Step B 1-[2,4-Dichloro-5-(1-methylethoxy)phenyl]- 3-trifluoromethyl-4, 5-dihydro-1,2,4-triazol- 5(1H)-one

Under a dry nitrogen atmosphere a stirred solution of 2.1 g (0.0062 mole) of N-[2,4-dichloro-5-(1-methylethoxy)anilino]trifluoroacetamidine in 130 mL of toluene was cooled in an ice bath. To this was added 5.2 mL (0.037 mole) of triethylamine followed by the dropwise addition of 45.6 mL of a 2.9% (0.013 mole) phosgene in toluene solution. After complete addition the mixture was heated quickly to 65°C and stirred at that temperature for 45 minutes. The mixture was allowed to cool to room temperature and stir for approximately 18 hours. The mixture was diluted with 25 mL of water and stirred vigorously for a brief period. Sufficient concentrated hydrochloric acid was added to make the aqueous phase acidic (pH 2). The acidic aqueous phase and the organic phase were shaken briskly after which the organic phase was separated from the mixture and saved for further purification. The aqueous phase was extracted with methylene chloride and the extract evaporated to leave a yellow solid. This solid was dissolved in toluene and the resultant solution added to the saved organic phase from above. The combined organic phase was stirred at room temperature with decolorizing carbon and filtered through a celite pad. The filtrate was extracted with a 1 N sodium hydroxide solution. This extract was washed with toluene and acidified with concentrated hydrochloric acid to pH 2. Sodium chloride was added to the acidic solution to the point of saturation. A precipitate formed upon cooling this solution and was collected by filtration. The filter cake was rinsed with several portions of ice cold water and dried under reduced pressure to yield 1.8 g of 1-[2,4-dichloro-5-(1-methylethoxy)phenyl]-3-trifluoromethyl-4, 5-dihydro-1,2,4-triazol-5(1H)-one (mp 160-161ºC), Compound 36.

The nmr was consistent with the proposed structure. Analysis calc'd for

C₁₂H₁₀Cl₂F₃N₃O₂: C 40.47; H 2.83; N 11.80; Found: C 39.01; H 2.96; N 11.38.

Also prepared by the process of Example 2, Step B, were 1-[2,4-dichloro-5-(1-methylethoxy)phenyl]-3-chlorodifluoromethyl-4, 5-dihydro-1,2,4-triazol-5(1H)-one and 1-(4-chloro-2-fluoro-5-methoxyphenyl)-3-chlorodifluoromethyl-4, 5-dihydro-1,2,4-triazol-5(1H)-one (Compound 30) from the correspondingly substituted chlorodifluoroacetamidine.

Step C 1-[2,4-Dichloro-5-(1-methylethoxy)phenyl]- 3-trifluoromethyl-4, 5-dihydro-4-methyl-1,2,4- triazol-5(1H)-one

Under a dry nitrogen atmosphere 0.1 g (0.0038 mole) of dry sodium hydride was added to a stirred solution of 1.3 g (0.0035 mole) of 1-[2,4-dichloro-5-(1-methylethoxy)phenyl]-3-trifluoromethyl-4, 5-dihydro-1,2,4-triazol-5(1H)-one in 30 mL of N,N-dimethylformamide. The mixture was stirred at room temperature for 20 minutes and 0.6 g (0.0038 mole) of iodomethane was added. After complete addition the mixture was warmed to 65°C and stirred at that temperature for one hour. The mixture was allowed to cool to room temperature and stir for approximately 18 hours. Most of the solvent was removed by distillation under reduced pressure to leave a liquid residue. This residue was partitioned between water and diethyl ether. The organic phase was washed first with a 2 N sodium hydroxide solution followed by water. The organic solution was dried over an anhydrous magnesium sulfate and filtered. The filtrate was evaporated under reduced pressure to yield 1.2 g of 1-[2,4-dichloro-5-(1-methylethoxy)phenyl]-3-trifluoromethyl-4, 5-dihydro-4-methyl-1,2,4-triazol-5(1H)-one as a solid (mp 96-98°C), Compound 35.

The nmr spectrum was consistent with the proposed structure. Analysis calc'd for

C₁₃H₁₂Cl₂F₃N₃O₂: C 42.18; H 3.27; N 11.35; Found: C 41.52; H 3.18; N 11.14.

Compound 31 was prepared by the manner of Example 1, Step C, from Compound 30. Compound 24 was prepared in an analogous manner from 1-[2,4-dichloro-5-(1-methylethoxy)phenyl]-3-chlorodifluoromethyl-4, 5-dihydro-1,2,4-triazol-5(1H)-one using potassium carbonate and acetone in place of sodium hydride and N,N-dimethyIformamide.

Characterizing properties of some of the compounds of the invention are given in the following Table.

TABLE 2

Cmpd. Melting Elemental Analysis No. Point (°C) Empirical Formula C H N

1 Solid C₁₀H₅CI₂F₄N₃O₂

2 190-192 C₁₀H₇Cl₂F2N₃O₂ C 38.73 2.27 13.55

F 38.74 2.26 13.31

3 86-88 C₁₁H₉F₄N₃O₂

4 113-115 C₁₁H₁₁F₂N₃O₂

5 131-138 C₁₁H₇CI₂F₄N₃O₂

6 156-159 C₁₁H₉Cl₂F₂N₃O₂

7 121-124 C₁₃H₉CI₂F₂N₃O₂

8 Solid C₁₃H₇CI₂F₄N₃O₂

9 Oil C₁₄H₁₁CI₂F₄N₃O₃

10 Solid C₁₂H₁₁CI₂F₂N₃O₂ .

11 95-97 C1₃H₁₃CI₂F₂N₃O₂

12 81-83 C₁₅H₁₅CI₂F₂N₃O₂

13 69-74 C₁₅H₁₁CI₂F₂N₃O₂

14 Oil C₁₅H₁₅CI₂F₂N₃O₄

15 Oil C₁₇H₁₇CI₂F₂N₃O₄

16 Solid C₁₃H₁₁CI₂F₂N₃O₄

17 132-135 C₁₂H₈Cl₂F₂N₄O₂

18 190-193.5 C₁₂H₁₀Cl₂F₂N₄O₂

19 Oil C₁₄H₁₃CI₂F₂N₃O₃

20 106-107 C₁₃H₉ClF₃N₃O₂ C 47.08 2.73 12.67 F 46.98 2.80 12.61

21 Oil C₁₅H₁₅CIF₃N₃O₄ TABLE 2 (Continued)

Cmpd. Melting Elemental Analysis No. Point (°C) Empirical Formula C H N

22 127-129 C₁₁H₉CIF₃N₃O₂ C 42.94 2.95 13.66

F 42.74 3.15 13.35

23 153-155 C₁₀H₇CIF₃N₃O₂

24 69-72 C₁₃H₁₂Cl₃F₂N₃O₂ C 40.39 3.13 10.87

F 40.92 3.28 10.96

25 146-147.5 C₁₃H₈Cl₃F₂N₃O₂ C 40.81 2.11 10.98

F 40.48 2.04 10.61

26 Oil C₁₅H₁₄CI₃F₂N₃O₄

27 Oil C₁₄H₁₅Cl₂F₂N₃O₂

28 120-124 C₁₁H₉CI₂F₂N₃O₂

29 104-107 C₁₄H₁₁Cl₂F₂N₃O₂ C 46.43 3.06 11.60

F 46.85 3.10 11.54

30 200-205 C₁₀H₆Cl₂F₃N₃O₂ C 36.61 1.84 12.81

F 37.33 2.16 12.63

31 78-88 C₁₀H₈Cl₂F₃N₃O₂

32 114-116 C₁₂H₁₁ClF₃N₃O₃

33 Solid C₁₂H₁₁CIF₃N₃O₃

34 Oil C₁₄H₈ClF₃N₄O₂

35 96-98 C₁₃H₁₂Cl₂F₃N₃O₂ C 42.18 3.27 11.35

F 41.52 3.18 11.14

36 160-161.5 C₁₂H₁₀CI₂F₃N₃O₂ C 40.47 2.83 11.80

F 39.01 2.96 11.38

37 132.5-134.5 C₁₃H₈Cl₂F₃N₃O₂ C 42.63 2.20 11.48

F 42.83 2.54 10.70

38 174-175 C₁₀H₆Cl₂F₃N₃O₂ C 36.61 1.84 12.81

F 38.24 2.14 12.10

39 162-166 C₁₉H₁₅Cl₂F₃N₄O₅S

40 Oil C₁₇H₁₉ClF₃N₃O₄ HERBICIDAL ACTIVITY

The plant tests species used in demonstrating the herbicidal activity of compounds of this invention include cotton (Gossypium hirsutum var. Stoneville), soybean (Glycine max var. Williams), field corn (Zea mays var. Agway 595S), wheat (Triticum aestivium var. Prodax), field bindweed (Convolvulus arvensis), morningglory (Ipomeea lacunosa or Ipomea hederacea, velvetleaf (Abutilon theophrasti), barnyardgrass (Echinochloa crus galli), green foxtail (Setaria viridis), johnsongrass ( Sorghum halepense), yellow nutsedge (Cyperus esculentus), and rice (Oryza sativa).

Seeds or tubers of the plant test species were planted in furrows in steam sterilized sandy loam soil contained in disposable fiber flats. A topping soil of equal portions of sand and sandy loam soil was placed uniformly on top of each flat to a depth of approximately 0.5 cm.

The flats for the preemergence test were watered, then drenched with the appropriate amount of a solution of the test compound in a mixture of acetone and water containing a small amount (up to 0.5% v/v) of sorbitan monolaurate emulsifier/solubilizer. The concentration of the test compound in solution was varied to give a range of application rates, generally 8.0 kg/ha and submultiples thereof. The flats were placed in a greenhouse and watered regularly at the soil surface for 21 days at which time phytotoxicity data were recorded.

The flats for the postemergence test were placed in a greenhouse and watered for 8-10 days, then the foliage of the emerged test plants was sprayed with a solution of the test compound in acetone-water containing up to 0.5% sorbitan monolaurate. After spraying the foliage was kept dry for 24 hours, then watered regularly for 21 days, and phytotoxicity data recorded.

Phytotoxicity data were taken as percent control. Percent control was determined by a method similar to the 0 to 100 rating system disclosed in "Research Methods in Weed Science," 2nd ed., B. Truelove, Ed.; Southern Weed Science Society; Auburn University, Auburn, Alabama, 1977. The present rating system is as follows:

Herbicide Rating System

Rating Description Percent of Main Crop Weed Control Categories Description Description 0 No effect No crop No weed reduction or control injury

10 Slight discoloraVery poor tion or stunting weed control

20 Slight Some discoloraPoor weed effect tion, stunting control or stand loss

30 Crop injury more Poor to pronounced but not deficient not lasting weed control

40 Moderate injury, Deficient crop usually weed control recovers

50 Moderate Crop injury more Deficient to effect lasting, recovery moderate weed control

60 Lasting crop Moderate injury no recovery weed control

70 Heavy injury and Control stand loss somewhat less than satisfactory

80 Severe Crop nearly desSatisfactroyed a few tory to good survivors weed control

90 Only occasional Very good to live plants left excellent control

100 Complete Complete crop Complete effect destruction weed destruction Herbicidal data at selected application rates are given for various compounds of the invention in the tables below. The test compounds are identified in the tables below by numbers which correspond to those used above.

In the Tables of herbicidal data below "kg/ha" is kilograms per hectare.

Table 3

Pre-emergence Herbici dal Activity

% Control

Compound No. 1 2 3 4 Rate (Kg/ha) 8.0 8.0 8.0 8.0 Species

COTTON 100 100 0 10

SOYBEAN 100 60 0 20

FIELD CORN 90 90 0 0

RICE - - - -

WHEAT 90 90 0 0

FIELD BINDWEED 100 100 0 20

MORNINGGLORY 100 90 0 70

VELVETLEAF 100 100 0 90

BARNYARDGRASS 100 90 0 70

GREEN FOXTAIL 100 100 0 100

JOHNSONGRASS 100 90 0 70

YELLOW NUTSEDGE - - - -

Compound No. 5 6 7 8 Rate (Kg/ha) 2.0 2.0 2.0 2.0 Species

COTTON 50 100 100 100

SOYBEAN 70 90 100 100

FIELD CORN 100 100 100 100

RICE 90 100 100 100

WHEAT 100 100 100 100

FIELD BINDWEED 70 80 100 100

MORNINGGLORY 80 100 100 100

VELVETLEAF 100 100 100 100

BARNYARDGRASS 100 100 100 100

GREEN FOXTAIL 100 100 100 100

JOHNSONTAIL 100 100 100 100

YELLOW NUTSEDGE 90 100 90 90 Table 3

(Continued)

Compound No . 9 10 11 12 Rate (Kg/ha) 2.0 2.0 1.0 1.0 Species

COTTON 90 10 60 40

SOYBEAN 100 0 100 60

FIELD CORN 100 70 90 80

RICE 100 - 80 30

WHEAT 100 0 90 40

FIELD BINDWEED 90 30 90 50

MORNINGGLORY 100 50 90 80

VELVETLEAF 100 70 100 100

BARNYARDGRASS 100 60 100 100

GREEN FOXTAIL 100 40 100 100

JOHNSONGRASS 100 80 100 90

YELLOW NUTSEDGE 90 - 80 20

Compound No. 13 14 15 16 Rate (Kg/ha) 2.0 2.0 2.0 1.0

Species

COTTON 100 100 90 60

SOYBEAN 100 30 0 0

FIELD CORN 90 40 70 0

RICE 90 80 40 10

WHEAT 90 80 80 0

FIELD BINDWEED 100 100 100 60

MORNINGGLORY 100 80 100 70

VELVETLEAF 100 100 100 10

BARNYARDGRASS 100 100 100 60

GREEN FOXTAIL 100 100 100 10

JOHNSONGRASS 100 100 90 40

YELLOW NUTSEDGE 80 100 80 20 Table 3 (Continued)

Compound No. 17 18 19 20 Rate (Kg/ha) 1.0 1.0 1.0 0.125 Species

COTTON 100 40 100 100

SOYBEAN 60 10 90 100

FIELD CORN 100 80 100 100

RICE 100 30 100 100

WHEAT 100 0 100 100

FIELD BINDWEED 90 90 70 100

MORNINGGLORY 100 100 100 100

VELVETLEAF 100 90 100 100

BARNYARDGRASS 100 80 100 100

GREEN FOXTAIL 100 100 100 100

JOHNSONGRASS 100 70 100 100

YELLOW NUTSEDGE 90 30 100 90

Compound No. 21 22 23 24 Rate (Kg/ha) 1.0 1.0 8.0 1.0Species

COTTON 80 80 100 0

SOYBEAN 10 100 100 60

FIELD CORN 40 100 100 90

RICE 70 100 - 60

WHEAT 80 100 100 70

FIELD BINDWEED 80 100 100 60

MORNINGGLORY 80 100 100 10

VELVETLEAF 100 100 100 60

BARNYARDGRASS 100 100 100 100

GREEN FOXTAIL 100 100 100 100

JOHNSONGRASS 70 100 100 100

YELLOW NUTSEDGE 100 100 - 0 Table 3

(Continued)

Compound No. 25 26 27 28 Rate (Kg/ha) 0.5 2.0 1.0 2.0 Species

COTTON 20 50 20 10

SOYBEAN 70 50 20 10

FIELD CORN 100 30 90 90

RICE 60 80 70 30

WHEAT 40 20 80 30

FIELD BINDWEED 100 100 50 10

MORNINGGLORY 50 90 80 20

VELVETLEAF 100 100 100 20

BARNYARDGRASS 100 100 100 70

GREEN FOXTAIL 100 90 100 100

JOHNSONGRASS 90 40 100 90

YELLOW NUTSEDGE 60 50 60 10

Compound No. 29 30 31 32

Rate (Kg/ha) 0.5 8.0 0.5 0.5

Species

COTTON 40 0 30 90

SOYBEAN 100 0 60 100

FIELD CORN 100 0 90 100

RICE 80 - 70 100

WHEAT 100 0 90 100

FIELD BINDWEED 100 0 20 100

MORNINGGLORY 60 0 20 100

VELVETLEAF 100 0 100 100

BARNYARDGRASS 100 0 100 100

GREEN FOXTAIL 100 0 100 100

JOHNSONGRASS 100 0 60 100

YELLOW NUTSEDGE 70 - 80 100 Table 3

(Continued)

Compound No. 33 34 35 36 Rate (Kg/ha) 1.0 0.5 1.0 8.0 Species

COTTON 90 80 20 0

SOYBEAN 80 90 30 0

FIELD CORN 100 90 90 0

RICE 90 80 60 -

WHEAT 100 90 50 0

FIELD BINDWEED 100 90 80 0

MORNINGGLORY 90 90 80 0

VELVETLEAF 100 100 100 0

BARNYARDGRASS 100 100 100 0

GREEN FOXTAIL 100 100 100 0

JOHNSONGRASS 100 90 100 0

YELLOW NUTSEDGE 90 70 20 -

Compound No. 37 39 40 Rate (Kg/ha) 1.0 1.0 2.0 Species

COTTON 80 100 100

SOYBEAN 100 70 70

FIELD CORN 100 70 100

RICE 95 90 95

WHEAT 100 70 100

FIELD BINDWEED 100 100 100

MORNINGGLORY 100 100 95

VELVETLEAF 100 100 100

BARNYARDGRASS 100 100 100

GREEN FOXTAIL 100 100 100

JOHNSONGRASS 100 95 100

YELLOW NUTSEDGE 60 100 100 Table 4

Post-emergence Herbicidal Activity

% Control

Compound No. 1 2 3 4 Rate (Kg/ha) 8.0 8.0 8.0 8.0 Species

COTTON 100 100 40 10

SOYBEAN 90 90 0 20

FIELD CORN 100 90 0 0

RICE - - - -

WHEAT 100 100 0 0

FIELD BINDWEED 100 100 0 10

MORNINGGLORY 100 100 0 0

VELVETLEAF 100 100 0 0

BARNYARDGRASS 100 100 0 10

GREEN FOXTAIL 100 100 80 0

JOHNSONGRASS 100 100 30 20

YELLOW NUTSEDGE - - - -

Compound No. 5 6 7 8 Rate (Kg/ha) 2.0 2.0 2.0 2.0 Species

COTTON 100 80 100 100

SOYBEAN 100 90 100 100

FIELD CORN 100 100 100 100

RICE 100 100 100 100

WHEAT 100 100 100 100

FIELD BINDWEED 90 100 100 100

MORNINGGLORY 80 100 100 100

VELVETLEAF 100 100 100 100

BARNYARDGRASS 100 100 100 100

GREEN FOXTAIL 100 100 100 100

JOHNSONGRASS 100 100 100 100

YELLOW NUTSEDGE 100 100 90 80 Table 4 (Continued)

Compound No. 9 10 11 12 Rate (Kg/ha) 2.0 8.0 1.0 1.0 Species

COTTON 100 40 100 100

SOYBEAN 100 20 90 70

FIELD CORN 100 40 100 80

RICE 100 - 90 30

WHEAT 100 0 100 90

FIELD BINDWEED 100 100 100 90

MORNINGGLORY 100 0 100 100

VELVETLEAF 100 80 100 100

BARNYARDGRASS 100 0 100 100

GREEN FOXTAIL 100 40 100 100

JOHNSONGRASS 100 0 100 90

YELLOW NUTSEDGE 80 - 60 0

Compound No. 13 14 15 16 Rate (Kg/ha) 2.0 2.0 2.0 1.0 Species

COTTON 100 100 100 60

SOYBEAN 100 50 60 40

FIELD CORN 100 70 100 40

RICE 90 80 100 10

WHEAT 100 80 100 0

FIELD BINDWEED 100 100 100 100

MORNINGGLORY 100 80 80 80

VELVETLEAF 100 100 100 100

BARNYARDGRASS 100 100 80 100

GREEN FOXTAIL 100 100 100 100

JOHNSONGRASS 100 100 80 40

YELLOW NUTSEDGE 70 70 50 0 Table 4

(Continued)

Compound No. 17 18 19 20 Rate (Kg/ha) 1.0 1.0 1.0 0.125 Species

COTTON 100 50 90 100

SOYBEAN 60 20 80 80

FIELD CORN 90 20 90 100

RICE 30 10 100 100

WHEAT 100 10 100 100

FIELD BINDWEED 100 100 100 100

MORNINGGLORY 100 90 100 100

VELVETLEAF 100 100 100 100

BARNYARDGRASS 100 80 100 100

GREEN FOXTAIL 100 100 100 100

JOHNSONGRASS 100 60 100 100

YELLOW NUTSEDGE 90 0 90 80

Compound No. 21 22 23 24 Rate (Kg/ha) 1.0 1.0 8.0 1.0 Species

COTTON 100 100 100 100

SOYBEAN 50 100 90 40

FIELD CORN 70 100 100 30

RICE 90 100 - 10

WHEAT 100 100 100 10

FIELD BINDWEED 100 100 100 90

MORNINGGLORY 100 100 100 60

VELVETLEAF 100 100 100 100

BARNYARDGRASS 90 100 100 90

GREEN FOXTAIL 100 100 100 90

JOHNSONGRASS 90 90 100 50

YELLOW NUTSEDGE 90 100 - 0 Table 4

(Continued)

Compound No. 25 26 27 28 Rate (Kg/ha) 0.5 2.0 1.0 0.5

Species

COTTON 100 100 90 90

SOYBEAN 80 50 70 30

FIELD CORN 70 20 80 30

RICE 40 70 90 40

WHEAT 30 30 80 20

FIELD BINDWEED 100 100 80 30

MORNINGGLORY 100 90 70 20

VELVETLEAF 100 90 100 70

BARNYARDGRASS 30 60 80 10

GREEN FOXTAIL 90 80 100 100

JOHNSONGRASS 30 20 90 70

YELLOW NUTSEDGE 20 40 10 10

Compound No. 29 30 31 32 Rate (Kg/ha) 0.5 8.0 0.5 0.5

Species

COTTON 90 30 90 100

SOYBEAN 50 10 70 100

FIELD CORN 90 10 60 100

RICE 40 - 40 100

WHEAT 60 10 60 100

FIELD BINDWEED 90 30 90 100

MORNINGGLORY 90 30 70 100

VELVETLEAF 100 10 100 100

BARNYARDGRASS 70 10 ND 100

GREEN FOXTAIL 90 20 90 100

JOHNSONGRASS 80 10 20 100

YELLOW NUTSEDGE 50 - 70 100 Table 4

(Continued)

Compound No. 33 34 35 36* Rate (Kg/ha) 1.0 0.5 1.0 8.0 Species

COTTON 80 90 80 0

SOYBEAN 70 80 70 30

FIELD CORN 80 100 60 20

RICE 50 90 30 -

WHEAT 80 50 60 20

FIELD BINDWEED 70 90 80 0

MORNINGGLORY 100 70 80 20

VELVETLEAF 100 100 100 0

BARNYARDGRASS 90 30 90 20

GREEN FOXTAIL 100 80 90 0

JOHNSONGRASS 80 50 80 20

YELLOW NUTSEDGE 40 40 20 _

Compound No. 37 39 40 Rate (Kg/ha) 1.0 1.0 2.0 Species

COTTON 100 100 100

SOYBEAN 95 90 95

FIELD CORN 100 100 100

RICE 95 50 90

WHEAT 95 95 100

FIELD BINDWEED 100 100 100

MORNINGGLORY 100 100 100

VELVETLEAF 100 100 100

BARNYARDGRASS 100 100 100

GREEN FOXTAIL 100 100 100

JOHNSONGRASS 100 100 100

YELLOW NUTSEDGE 70 95 100

*Data given are data for % Kill For herbicidal application, the active compounds as above defined are formulated into herbicidal compositions by admixture in herbicidally effective amounts with adjuvants and carriers normally employed in the art for facilitating the dispersion of active ingredients for the particular utility desired, recognizing the fact that the formulation and mode of application of a toxicant may affect the activity of the material in a given application. Thus, for agricultural use the present herbicidal compounds may be formulated as granules of relatively large particle size, water-soluble or water-dispersible granules, as powdery dusts, as wettable powders, as emulsifiable concentrates, as solutions or as any of several other known types of formulations, depending on the desired mode of application.

For preemergence application these herbicidal compositions are usually applied either as sprays, dusts, or granules in the areas in which suppression of vegetation is desired. For postemergence control of established plant growth, sprays or dusts are most commonly used. These formulations may contain as little as 0.5% to as much as 95% or more by weight of active ingredient.

Dusts are free flowing admixtures of the active ingredient with finely divided solids such as talc, natural clays, kieselguhr, flours such as walnut shell and cotton seed flours, and other organic and inorganic solids which act as dispersants and carriers for the toxicant; these finely divided solids have an average particle size of less than about 50 microns. A typical dust formulation useful herein is one containing 1.0 part of the herbicidal compound and 99.0 parts of talc.

Wettable powders, also useful formulations for both pre and postemergence herbicides, are in the form of finely divided particles which disperse readily in water or other dispersant. The wettable powder is ultimately applied to the soil either as a dry dust or as an emulsion in water or other liquid. Typical carriers for wettable powders include Fuller's earth, kaolin clays, silicas, and other highly absorbent, readily wet inorganic diluents. Wettable powders normally are prepared to contain about 5-80% of active ingredient, depending on the absorbency of the carrier, and usually also contain a small amount of a wetting, dispersing or emulsifying agent to facilitate dispersion. For example, a useful wettable powder formulation contains 80.8 parts of the herbicidal compound, 17.9 parts of Palmetto clay, and 1.0 part of sodium lignosulfonate and 0.3 part of sulfonated aliphatic polyester as wetting agents. Frequently, additional wetting agent and/or oil will be added to the tank-mix for postempergence application to facilitate dispersion on the foliage and absorption by the plant.

Other useful formulations for herbicidal applications are emulsifiable concentrates. Emulsifiable concentrates are homogeneous liquid or paste compositions dispersible in water or other dispersant, and may consist entirely of the herbicidal compound and a liquid or solid emulsifying agent, or may also contain a liquid carrier, such as xylene, heavy aromatic naphthas, isophorone, or other non-volatile organic solvent. For herbicidal application these concentrates are dispersed in water or other liquid carrier, and normally applied as a spray to the area to be treated. The percentage by weight of the essential active ingredient may vary according to the manner in which the composition is to be applied, but in general comprises 0.5 to 95% of active ingredient by weight of the herbicidal composition.

Typical wetting, dispersing or emulsifying agents used in agricultural formulations include, for example, the alkyl and alkylaryl sulfonates and sulfates and their sodium salts; polyhydric alcohols; and other types of surface active agents, many of which are available in commerce. The surface active agent, when used, normally comprises 1% to 15% by weight of the herbicidal composition.

Other useful formulations for herbicidal applications include simple solutions of the active ingredient in a dispersant in which it is completely soluble at the desired concentration, such as acetone, alkylated naphthalenes, xylene or other organic solvents. Granular formulations, wherein the toxicant is carried on relatively coarse particles, are of particular utility for aerial distribution or for penetration of cover crop canopy. Pressurized sprays, typically aerosols wherein the active ingredient is dispersed in finely divided form as a result of vaporization of a low boiling dispersant solvent carrier, such as the Freons, may also be used. Water-soluble or water-dispersible granules are also useful formulations for herbicidal application of the present compounds. Such granular formulations are free-flowing, non-dusty, and readily water-soluble or water-miscible. The soluble or dispersible granular formulations described in U.S. patent No. 3,920,442 are useful herein with the present herbicidal compounds.

The active herbicidal compounds of this invention may be formulated and/or applied with insecticides, fungicides, nematicides, plant growth regulators, fertilizers, or other agricultural chemicals and may be used as effective soil sterilants as well as selec tive herbicides in agriculture. In applying an active compound of this invention, whether formulated alone or with other agricultural chemicals, an effective amount and concentration of the active compound is of course employed.

The active herbicidal compounds of this invention may be used in combination with other herbicides, e.g. they may be mixed with, say, an equal or larger amount of a known herbicide such as chloroacetanilide herbicides such as 2-chloro-N-(2,6-diethylphenyl)-N-(methoxymethyl)acetamide (Alachlor), 2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-(1-methylethyl)acetamide (Metolachlor), and N-chloroacetyl-N-(2,6-diethylphenyl)glycine (Diethatyl-ethyl); benzothiadiazinone herbicides such as 3-(1-methylethyl)-(1H)-2,1,3-benzothiadiazin-4-(3H)-one-2, 2-dioxide (Bentazon); triazine herbicides such as 6-chloro-N-ethyl-N-(1-methylethyl)-1,3,5-triazine-2, 4-diamine (Atrazine), and 2- [4-chloro-6-(ethylamino)-1,3,5-triazin-2-yl]- amino -2-methylpropanenitrile (Cyanazine); dinitrolaniline herbicides such as 2,6-dinitro-N,N-dipropyl-4-(trifluoromethyl)benzeneamine (Trifluralin); and aryl urea herbicides such as N'-(3,4-dichlorophenyl)-N,N-dimethylurea (Diuron) and N,N-dimethyl-N'-[3-(trifluoromethyl)phenyl]-urea (Fluometuron).

It is apparent that various modifications may be made in the formulation and application of the compounds of this invention, without departing from the inventive concepts herein, as defined in the following claims.

Claims

Claims:

1. A herbicidal compound (I) which is a 1-aryl-4,5-dihydro-1,2,4-triazol-5(1H)-one characterized by having a haloalkyl group of 1-4 carbon atoms on the carbon atom at the 3-position of the dihydrotriazol ring, and whose 1-aryl radical is such that the 3-Methyl-4-Difluoromethyl Analog of said compound (I) is a herbicide, said Analog being a compound which is otherwise identical to said compound (I) except that said Analog has, at the 3- and 4-positions of the dihydrotriazol ring, a CH₃ and a CHF₂ substituent, respectively, the halogen of said haloalkyl being selected from F, Cl and Br, said herbicidal compound (I) not having: (a) an OR ²⁰ group at the 5-position of its 1-aryl group, R²⁰ being three- to eight-membered ring heterocyclic group of one or two, same or different, ring heteroatoms selected from oxygen, sulfur, and nitrogen or an alkyl radical substituted with said heterocyclic group, said heterocyclic group being unsubstituted or substituted with one or more substituents selected from halogen, alkyl, and haloalkyl, or said heterocyclic group being adjoined to a benzene ring at two adjacent ring carbon atoms to form a benzo-heterocycle bicyclic group, said sulfur heteroatom being present in divalent form, S-oxide form, or S-dioxide form.

2. A herbicidal compound (I) which is a 1-aryl-4,5-dihydro-1,2,4-triazol-5(1H)-one characterized by having a haloalkyl group of 1-4 carbon atoms on the carbon atom at the 3-position of the dihydrotriazol ring, and whose 1-aryl radical is such that the 3-Methyl-4-Difluoromethyl Analog of said compound (I) is a herbicide, said Analog being a compound which is otherwise identical to said compound (I) except that said Analog has, at the 3- and 4-positions of the dihydrotriazol ring, a CH₃ and a CHF₂ substituent, respectively, the halogen of said haloalkyl being selected from F, Cl and Br, said herbicidal compound (I) not having:

(a) an OR ²⁰ group at the 5-position of its 1-aryl group,

R ²⁰ being three- to eight-membered ring heterocyclic group of one or two, same or different, ring heteroatoms selected from oxygen, sulfur, and nitrogen or an alkyl radical substituted with said heterocyclic group, said heterocyclic group being unsubstituted or substituted with one or more substituents selected from halogen, alkyl, and haloalkyl, or said heterocyclic group being adjoined to a benzene ring at two adjacent ring carbon atoms to form a benzo-heterocycle bicyclic group, said sulfur heteroatom being present in divalent form, S-oxide form, or

S-dioxide form;

(b) an OSO₂R ²¹ group at the 5-position of its 1-aryl group, R ²¹ being alkyl, haloalkyl, cyanoalkyl, arylalkyl, cyclic alkyl, alkenyl, haloalkenyl, arylalkenyl, alkynyl, haloalkynyl, arylalkynyl, aryl, or a group of the formula -(CH₂)_mNR³R⁴ or -alkyl-Y-R⁵ wherein m is 0 to 5, R³ is hydrogen or alkyl, R⁴ is alkyl or a group of the formula -alkyl-Y ³-R⁸, Y and Y³ are independently oxygen or S(O) _r in which r is 0 to 2, and R⁵ and R⁸ are independently alkyl, alkoxycarbonylalkyl, alkenyl, or alkynyl;

(c) where said herbicidal compound (I) has a haloalkyl group at the 4-position of the dihydrotriazol ring, an OR²³COOR²⁴ group at the 5-position of its 1-aryl group, R²³ being alkylene or haloalkylene, and R ²⁴ being alkyl or H or a salt-forming group;

(d) an OR²⁵COZR²⁶ group at the 5-position of its 1-aryl group, R ²⁵ being alkylene or haloalkylene, and

R²⁶ being substituted alkyl, alkenyl, alkynyl, or a monovalent cyclic group having a ring of 5 or 6 atoms whose valence is on a carbon atom of said ring; the substituent on said substituted alkyl of R²⁶ being: nitro, halo, furyl or tetrahydrofuryl, acetyl, cyano,

where is the residue of ammonia or a primary or secondary amine,

-COOR^IV where R^IV is the residue of an alcohol, phenyl or substituted phenyl, alkylamino, dialkylamino, or a trialkylammonium salt, alkoxy, alkylthio, alkylsulfinyl or alkylsulfonyl, or phenoxy, phenylthio, phenylsulfinyl, or phenylsulfonyl.

(e) an OR²⁷ group at the

5-position of its 1-aryl group R ²⁷ being alkylene or haloalkylene; and

being NH₂ or the residue of a primary or secondary amine or of a sulfonamide;

(f) an OR³⁰ COOR³¹ group at the 5-posi tion of its aryl group,

R ³⁰ being alkylene or haloalkylene and OR³¹ being the residue of an oxime;

(g) a -CH₂CH₂CH₂F group at the 4-position of the dihydrotriazol ring.

3. Process for preparing a herbicidal compound (I) which is a 1-aryl-4, 5-dihydro-1,2,4-tria¬zol-5(1H)-one characterized by having a haloalkyl group of 1-4 carbon atoms on the carbon atom at the 3-position of the dihydrotriazol ring, and whose 1-aryl radical is such that the 3-Methyl-4-Difluoromethyl Analog of said compound (I) is a herbicide, said Analog being a compound which is otherwise identical to said compound (I) except that said Analog has, at the 3- and 4-positions of the dihydrotriazol ring, a CH₃ and a CHF₂ substituent, respectively, the halogen of said haloalkyl being selected from F,

Cl and Br said herbicidal compound (I) not having an OR ²⁰ group at the 5-posιtιon of its 1-aryl group, R²⁰ being a three- to eight-membered ring heterocyclic group of one or two, same or different, ring heteroatoms selected from oxygen, sulfur, and nitrogen or an alkyl radical substituted with said heterocyclic group, said heterocyclic group being unsubstituted or substituted with one or more substituents selected from halogen, alkyl, and haloalkyl, or said heterocyclic group being adjoined to a benzene ring at two adjacent ring carbon atoms to form a benzo-heterocycle bicyclic group, said sulfur heteroatom being present in divalent form, S-oxide form, or S-dioxide form, which comprises:

(1) reacting (i) a 1-aryl-4, 5-dihydro-3-haloalkyl (of 1-4 carbon atoms ) -1,2,4-triazol-5(1H)-one having a hydrogen on the nitrogen atom at the 4-position of the dihydrotriazol ring with (ii) a reagent to replace said hydrogen by alkyl, haloalkyl, cyanoalkyl, alkenyl, alkynyl, alkoxyalkyl, amino, alkylamino, haloalkenyl, haloalkynyl, alkylthioalkyl, alkylsulfinylalkyl, or alkylsulfonylalkyl, or

(2) reacting (i) a 1-aryl-4, 5-dihydro3-haloalkyl (of 1-4 carbon atoms)-1,2,4-triazol-5(1H)-one having one of the following groups on the nitrogen atom at the 4-position of the dihydrotriazol ring: alkyl, haloalkyl, cyanoalkyl, alkenyl, alkynyl, alkoxyalkyl, amino, alkylamino, haloalkenyl, haloalkynyl, alkylthioalkyl, alkylsulfinylalkyl, or alkylsulfonylalkyl, and also having as its aryl group a benzene ring having a hydrogen at the 4-position of said benzene ring with (ii) a halogenating agent to replace said 4-position hydrogen by Cl or Br, or

(3) reacting (i) a 1-aryl-4, 5-dihydro-3-haloalkyl (of 1-4 carbon atoms )-1,2,4-triazol-5(1H)-one having one of the following groups on the nitrogen atom at the 4-position of the dihydrotriazol ring: alkyl, haloalkyl, cyanoalkyl, alkenyl, alkynyl, alkoxyalkyl, amino, alkylamino, haloalkenyl, haloalkynyl, alkylthioalkyl, alkylsulfinylalkyl, or alkylsulfonylalkyl, and also having as its aryl group a benzene ring having a hydroxyl substituent with (ii) a reagent to change the hydroxyl group to a phenyl-substituting group of said Analog other than said OR²⁰ group.

4. Process for preparing a herbicidal compound (I) which is a 1-aryl-4, 5-dihydro-1,2,4-triazol-5(1H)-one characterized by having a haloalkyl group of 1-4 carbon atoms on the carbon atom at the 3-position of the dihydrotriazol ring, and whose 1-aryl radical is such that the 3-Methyl-4-Difluoromethyl Analog of said compound (I) is a herbicide, said Analog being a compound which is otherwise identical to said compound (I) except that said Analog has, at the 3- and 4-positions of the dihydrotriazol ring, a CH₃ and a CHF₂ substituent, respectively, the halogen of said haloalkyl being selected from F,

Cl and Br, said herbicidal compound (I) not having:

(a) an OR ²⁰ group at the 5-position of its 1-aryl group, R ²⁰ being three- to eight-membered ring heterocyclic group of one or two, same or different, ring heteroatoms selected from oxygen, sulfur, and nitrogen or an alkyl radical substituted with said heterocyclic group, said heterocyclic group being unsubstituted or substituted with one or more substituents selected from halogen, alkyl, and haloalkyl, or said heterocyclic group being adjoined to a benzene ring at two adjacent ring carbon atoms to form a benzo-heterocycle bicyclic group, said sulfur heteroatom being present in divalent form, S-oxide form, or S-dioxide form;

(b) an OSO₂R ²¹ group at the 5-position of its 1-aryl group,

R ²¹ being alkyl, haloalkyl, cyanoalkyl, arylalkyl, cyclic alkyl, alkenyl, haloalkenyl, arylalkenyl, alkynyl, haloalkynyl, arylalkynyl, aryl, or a group of the formula -(CH₂)_mNR³R⁴ or -alkyl-Y-R⁵ wherein m is 0 to 5, R ³ is hydrogen or alkyl, R⁴ is alkyl or a group of the formula -alkyl-Y ³-R⁸, Y and

Y³ are independently oxygen or S(O)_r in which r is 0 to 2, and R ⁵ and R⁸ are independently alkyl, alkoxycarbonylalkyl, alkenyl, or alkynyl;

(c) where said herbicidal compound (I) has a haloalkyl group at the 4-position of the dihydrotriazol ring, an OR ²³COOR²⁴ group at the

5-position of its 1-aryl group,

R²³ being alkylene or haloalkylene, and R²⁴ being alkyl or H or a salt-forming group;

(d) an OR²⁵COZR²⁶ group at the

5-ρosition of its 1-aryl group,

R ²⁵ being alkylene or haloalkylene, and R²⁶ being substituted alkyl, alkenyl, alkynyl, or a monovalent cyclic group having a ring of

5 or 6 atoms whose valance is on a carbon atom of said ring; the substituent on said substituted alkyl of

R²⁶ being: nitro, halo, furyl or tetrahydrofuryl, acetyl,

cyano, where is the residue of ammonia or a primary or secondary amine, -COOR^IV where R^IV is the residue of an alcohol, phenyl or substituted phenyl, alkylamino, dialkylamino, or a trialkylammonium salt, alkoxy, alkylthio, alkylsulfinyl or alkylsulfonyl, or phenoxy, phenylthio, phenylsulfinyl, or phenylsulfonyl;

(e) an OR²⁷ group at the 5-posιtion of its 1-aryl group R ²⁷ being alkylene or haloalkylene; and

being NH₂ or the residue of a primary or secondary amine or of a sulfonamide;

(f) an OR³⁰COOR³¹ group at the 5-ρosition of its aryl group,

R³⁰ being alkylene or haloalkylene and OR³¹ being the residue of an oxime;

(g) a -CH₂CH₂CH₂F group at the 4-position of the dihydrotriazol ring; which comprises:

(1) reacting (i) a 1-aryl-4,5-dihydro- 3-haloalkyl (of 1-4 carbon atoms)-1,2,4-triazol-5(1H)-one having hydrogen on the nitrogen atom at the 4-position of the dihydrotriazol ring with (ii) a reagent to replace said hydrogen by alkyl, haloalkyl, cyanoalkyl, alkenyl, alkynyl, alkoxyalkyl, amino, alkylamino, haloalkenyl, haloalkynyl, alkylthioalkyl, alkylsulfinylalkyl, or alkylsulfonylalkyl, or

(2) reacting (i) a 1-aryl-4,5-dihydro-3-haloalkyl (of 1-4 carbon atoms)-1,2,4-triazol-5(1H)-one having one of the following groups on the nitrogen atom at the 4-position of the dihydrotriazol ring: alkyl, haloalkyl, cyanoalkyl, alkenyl, alkynyl, alkoxyalkyl, amino, alkylamino, haloalkenyl, haloalkynyl, alkylthioalkyl, alkylsulfinylalkyl, or alkylsulfonylalkyl, and also having as its aryl group a benzene ring having a hydrogen at the 4-position of said benzene ring with (ii) a halogenating agent to replace said 4-position hydrogen by Cl or Br, or

(3) reacting (i) a 1-aryl-4,5-dihydro-3-haloalkyl (of 1-4 carbon atoms)-1,2,4-triazol-5(1H)-one having one of the following groups on the nitrogen atom at the 4-position of the dihydrotriazol ring: alkyl, haloalkyl, cyanoalkyl, alkenyl, alkynyl, alkoxyalkyl, amino, alkylamino, haloalkenyl, haloalkynyl, alkylthioalkyl, alkylsulfinylalkyl, or alkylsulfonylalkyl, and also having as its aryl group a benzene ring having a hydroxyl substituent with (ii) a reagent to change the hydroxyl group to a phenyl-substituting group of said Analog other than one of said groups (a) through (g) listed above.