WO2006062979A1 - Herbicidal 6-cyclopropyl-substitute 4-aminopicolinic acid derivatives - Google Patents

Abstract

Compounds of Formula (I), and their N-oxides and agriculturally suitable salts, are disclosed which are useful for controlling undesired vegetation wherein R1 is H, F or Cl; R2 is H, C1-C4 alkyl optionally substituted with 1-2 R7, C2-C4 alkenyl optionally substituted with 1-2 R8, or C2-C4 alkynyl optionally substituted with 1-2 R9; or R2 is C(=O)R10, nitro, OR11, S(O)2R12, N(R13)R14 or N=C(R15)R16; R3 is H, C1-C4 alkyl optionally substituted with 1-2 R17 or C(=O)R10; or R2 and R3 are taken together as a radical selected from -(CH2)4-, -(CH2)5-, -CH2CH=CHCH2- and -(CH2)2O(CH2)2-, each radical optionally substituted with 1-2 R18; or R2 and R3 are taken together as =C(R19)N(R20)R21 or =C(R22)OR23; R4 is halogen; R5 is CO2H or a herbicidally effective derivative of CO2H; each R6 is independently halogen, C1-C6 alkyl, C1-C6 haloalkyl, C2-C6 alkenyl, C2-C6 haloalkenyl, C1-C3 alkoxy, C1-C2 haloalkoxy, C1-C3 alkylthio or C1-C2 haloalkylthio; and p is an integer from 0 to 5; and R7, R8, R9, R10, R11, R12, R13, R14, R15, R16, R17, R18, R19, R20, R21, R22 and R23 are as defined in the disclosure. Also disclosed are compositions comprising the compounds of Formula (I) and a method for controlling undesired vegetation which involves contacting the vegetation or its environment with an effective amount of a compound of Formula (I).

Description

TITLE

HERBICIDAL δ-CYCLOPROPYL-SUBSTITUTED 4-AMINOPICOLINIC ACID DERIVATIVES

FIELD OF THE INVENTION

This invention relates to certain pyridines, their JV-oxides, agriculturally suitable salts and compositions, and methods of their use for controlling undesirable vegetation.

BACKGROUND OF THE INVENTION

The control of undesired vegetation is extremely important in achieving high crop efficiency. Achievement of selective control of the growth of weeds especially in such useful crops as rice, soybean, sugar beet, corn (maize), potato, wheat, barley, tomato and plantation crops, among others, is very desirable. Unchecked weed growth in such useful crops can cause significant reduction in productivity and thereby result in increased costs to the consumer. The control of undesired vegetation in noncrop areas is also important. Many products are commercially available for these purposes, but the need continues for new compounds which are more effective, less costly, less toxic, environmentally safer or have different modes of action.

PCT Patent Publication WO 2004/089906 discloses herbicidally active 2-pyridine carboxylic acids of Formula i

wherein X is H or F; Y is C₁-C₄ alkyl, Ci-C₄ alkoxy substituted C₁-C₄ alkyl; C_j-C₄ thioalkoxy substituted C₁-C₄ alkyl, or C₂-C₃ alkenyl; and W is -NO₂, -N₃, -NR¹R², -N=R³R⁴ or-NHN=NR3R4.

SUMMARY OF THE INVENTION

This invention is directed to a compound of Formula I including all geometric and stereoisomers, N-oxides or agriculturally suitable salts thereof, agricultural compositions containing them and their use as herbicides:

wherein

R¹ is H, F or Cl;

R² is H, C₁-C₄ alkyl optionally substituted with 1-2 R⁷, C₂-C₄ alkenyl optionally substituted with 1-2 R⁸, or C₂-C₄ alkynyl optionally substituted with 1-2 R⁹; or R² is C(=O)R¹⁰, nitro, OR¹¹, S(O)₂R¹², N(R¹³)R¹⁴ Or N=C(R¹S)RIo;

R³ is H, C₁-C₄ alkyl optionally substituted with 1-2 R¹⁷ or C(=O)R¹⁰; or R² and R³ are taken together as a radical selected from -(CH₂)₄-, -(CH₂)₅-,

-CH₂CH=CHCH₂- and -(CH₂)₂O(CH₂)₂-, each radical optionally substituted with 1-2 R¹⁸; or R² and R³ are taken together as =C(R¹⁹)N(R²⁽>)R²¹ or =C(R²²)OR²³;

R⁴ is halogen;

R⁵ is CO₂H or a herbicidally effective derivative of CO₂H; each R⁶ is independently halogen, C₁-Cg alkyl, C₁-Cg haloalkyl, C₂-Cg alkenyl,

C₂-Cg haloalkenyl, C₁-C3 alkoxy, C₁-C₂ haloalkoxy, C₁-C3 alkylthio or C₁-C₂ haloalkylthio; each R⁷, R⁸ and R⁹ is independently halogen, C1-C3 alkoxy, C_j-C₃ haloalkoxy, C₁-C3 alkylthio, C₁-C₃ haloalkylthio, amino, C₁-C₃ alkylamino, C₂-C₄ dialkylamino or C₂-C₄ alkoxycarbonyl; each R¹⁰ is independently H, C₁-C₁₄ alkyl, C₁-C3 haloalkyl, C₁-C₄ alkoxy, phenyl, phenoxy or benzyloxy;

R^{1 1} is H, C₁-C₄ alkyl, C₁-C₃ haloalkyl or CHR²⁴C(O)OR²⁵; R¹² is C₁-C₄ alkyl or C₁-C₃ haloalkyl; R¹³ is H, C₁-C₄ alkyl or C(=O)R²6; R¹⁴ is H or C₁-C₄ alkyl; R¹⁵ is H, C₁-C₄ alkyl or phenyl optionally substituted with 1-3 R²⁷;

R¹⁶ is H or C₁-C₄ alkyl; or

R¹⁵ and R¹⁶ are taken together as -(CH₂)₄- or -(CH₂)₅-; each R¹⁷ is independently halogen, C₁-C₃ alkoxy, C₁-C₃ haloalkoxy,

C₁-C₃ alkylthio, C₁-C₃ haloalkylthio, amino, C₁-C₃ alkylamino, C₂-C₄ dialkylamino or C₂-C₄ alkoxycarbonyl; each R¹⁸ is independently halogen, C ^-C^ alkyl, Q-C3 alkoxy, ^-03 haloalkoxy, Q-C3 alkylthio, C1-C3 haloalkylthio, amino, C₁-C3 alkylamino, C₂-C₄ dialkylamino or C₂-C₄ alkoxycarbonyl; R¹⁹ is H or C₁-C₄ alkyl; R²⁰ and R²¹ are independently H or C₁-C₄ alkyl; or

R²⁰ and R²¹ are taken together as -(CH₂)₄-, -(CH₂)₅-, -CH₂CH=CHCH₂- or

-(CH₂)₂O(CH₂)₂-; R²² is H or C₁-C₄ alkyl; R23 is C₁-C₄ alkyl;

R24 is H, C₁-C₄ alkyl or C₁-C₄ alkoxy; R²⁵ is H, C₁-C₄ alkyl or benzyl.

R²⁶ is H, C₁-C₁₄ alkyl, C₁-C₃ haloalkyl, C₁-C₄ alkoxy, phenyl, phenoxy or benzyloxy; each R²⁷ is independently CH3, Cl or OCH₃; and p is an integer from 0 to 5.

More particularly, this invention pertains to a compound of Formula I, including all geometric and stereoisomers, N-oxides or agriculturally suitable salts thereof. This invention also relates to a herbicidal composition comprising a herbicidally effective amount of a compound of Formula I and at least one of a surfactant, a solid diluent or a liquid diluent. This invention further relates to a method for controlling the growth of undesired vegetation comprising contacting the vegetation or its environment with a herbicidally effective amount of a compound of Formula I (e.g., as a composition described herein). This invention also relates to a herbicidal mixture comprising a herbicidally effective amount of a compound of Formula I and an effective amount of at least one additional active ingredient selected from the group consisting of an other herbicide and a herbicide safener. This invention further relates to a herbicidal composition comprising a herbicidally effective amount of a compound of Formula I, an effective amount of at least one additional active ingredient selected from the group consisting of an other herbicide and a herbicide safener, and at least one of a surfactant, a solid diluent or a liquid diluent.

DETAILS OF THE INVENTION As used herein, the terms "comprises," "comprising," "includes," "including," "has,"

"having" or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus.

Further, unless expressly stated to the contrary, "or" refers to an inclusive or and not to an exclusive or. For example, a condition A or B is satisfied by any one of the following: A is true (or present) and B is false (or not present), A is false (or not present) and B is true (or present), and both A and B are true (or present).

Also, the indefinite articles "a" and "an" preceding an element or component of the invention are intended to be nonrestrictive regarding the number of instances (i.e. occurrences) of the element or component. Therefore "a" or "an" should be read to include one or at least one, and the singular word form of the element or component also includes the plural unless the number is obviously meant to be singular. In the above recitations, the term "alkyl", used either alone or in compound words such as "alkylthio" or "haloalkyl" includes straight-chain or branched alkyl, such as, methyl, ethyl, H-propyl, /-propyl, or the different butyl, pentyl or hexyl isomers. "Alkenyl" includes straight-chain or branched alkenes such as ethenyl, 1-propenyl, 2-propenyl, and the different butenyl, pentenyl and hexenyl isomers. "Alkenyl" also includes polyenes such as 1 ,2-propadienyl and 2,4-hexadienyl. "Alkynyl" includes straight-chain or branched alkynes such as ethynyl, 1-propynyl, 2-propynyl and the different butynyl, pentynyl and hexynyl isomers. "Alkynyl" can also include moieties comprised of multiple triple bonds such as 2,5-hexadiynyl. "Alkoxy" includes, for example, methoxy, ethoxy, n-propyloxy, isopropyloxy and the different butoxy isomers. "Alkoxyalkyl" denotes alkoxy substitution on alkyl. Examples of "alkoxyalkyl" include CH₃OCH₂, CH₃OCH₂CH₂, CH₃CH₂OCH₂ and CH₃CH₂OCH₂CH₂. "Alkylthio" includes branched or straight-chain alkylthio moieties such as methylthio, ethylthio, and the different propylthio and butylthio isomers. "Alkylamino", "dialkylamino", and the like, are defined analogously to the above examples. "Cycloalkyl" includes, for example, cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl. Examples of "cycloalkylalkyl" include cyclopropylmethyl, cyclopentylethyl, and other cycloalkyl moieties bonded to straight-chain or branched alkyl groups. "Alkylcycloalkyl" denotes alkyl substitution on a cycloalkyl moiety. Examples include 4-methylcyclohexyl and 3-ethylcyclopentyl. Synthetic methods for the preparation of TV-oxides of heterocycles (such as pyridines) and tertiary amines are very well known by one skilled in the art including the oxidation of heterocycles and tertiary amines with peroxy acids such as peracetic and /n-chloroperbenzoic acid (MCPBA), hydrogen peroxide, alkyl hydroperoxides such as /-butyl hydroperoxide, sodium perborate, and dioxiranes such as dimethyldioxirane. These methods for the preparation of N-oxides have been extensively described and reviewed in the literature, see for example: T. L. Gilchrist in Comprehensive Organic Synthesis, vol. 7, pp 748-750, S. V. Ley, Ed., Pergamon Press; M. Tisler and B. Stanovnik in Comprehensive Heterocyclic Chemistry, vol. 3, pp 18— 20, A. J. Boulton and A. McKillop, Eds., Pergamon Press; M. R. Grimmett and B. R. T. Keene in Advances in Heterocyclic Chemistry, vol. 43, pp 149— 161, A. R. Katritzky, Ed., Academic Press; M. Tisler and B. Stanovnik in Advances in Heterocyclic Chemistry, vol. 9, pp 285-291, A. R. Katritzky and A. J. Boulton, Eds., Academic Press; and G. W. H. Cheeseman and E. S. G. Werstiuk in Advances in Heterocyclic Chemistry, vol. 22, pp 390-392, A. R. Katritzky and A. J. Boulton, Eds., Academic Press. The term "halogen", either alone or in compound words such as "haloalkyl", includes fluorine, chlorine, bromine or iodine. Further, when used in compound words such as "haloalkyl", said alkyl may be partially or fully substituted with halogen atoms which may be the same or different. Examples of "haloalkyl" include F₃C, ClCH₂, CF₃CH₂ and CF₃CCl₂. The terms "haloalkenyl", "haloalkynyl", "haloalkoxy", "haloalkylthio", and the like, are defined analogously to the term "haloalkyl". Examples of "haloalkenyl" include (Cl)₂C=CHCH₂ and CF₃CH₂CH=CHCH₂. Examples of "haloalkoxy" include CF₃O, CCl₃CH₂O, HCF₂CH₂CH₂O and CF₃CH₂O. Fluoroalkyl and derived compound words such as fluoroalkoxy and fluoroalkylthio refer to an alkyl moiety wherein at least one of the hydrogens is replaced with fluorine. Examples of C^ fluoroalkoxy include CF₂HO and CF₃O.

The total number of carbon atoms in a substituent group is indicated by the "Cj-C_j" prefix where i and j are numbers from 1 to 14. For example, Cj-C₃ alkylthio designates methylthio through propylthio; C₂ alkoxyalkyl designates CH₃OCH₂; C₃ alkoxyalkyl designates, for example, CH₃CH(OCH₃), CH₃OCH₂CH₂ or CH₃CH₂OCH₂; and C₄ alkoxyalkyl designates the various isomers of an alkyl group substituted with an alkoxy group containing a total of four carbon atoms, examples including CH₃CH₂CH₂OCH₂ and CH₃CH₂OCH₂CH₂. Examples of "alkylcarbonyl" include C(O)CH₃, C(O)CH₂CH₂CH₃ and C(O)CH(CH₃)₂. Examples of "alkoxycarbonyl" include CH₃OC(=O), CH₃CH₂OC(=O), CH₃CH₂CH₂OC(=O) and (CH₃)₂CHOC(=O).

When a compound is substituted with a substituent bearing a subscript that indicates the number of said substituents can vary, when the number of said substituents is greater than 1, said substituents are independently selected from the group of defined substituents. When a group contains a substituent which can be hydrogen, for example R¹, R² and

R³, then, when this substituent is taken as hydrogen, it is recognized that this is equivalent to said group not being substituted. When a variable group is shown to be optionally attached to a position, for example (R⁶)_p wherein p may be O, then hydrogen may be at the position even if not recited in the variable group definition. When a position on a group is said to be "not substituted" or "unsubstituted", then hydrogen atoms are attached to take up any free valency.

"-CHfC(O)O(CH₂)_m}" means ; "-CHtO(CH₂)J" means

Compounds of this invention can exist as one or more stereoisomers. The various stereoisomers include enantiomers, diastereomers, atropisomers and geometric isomers. One skilled in the art will appreciate that one stereoisomer may be more active and/or may exhibit beneficial effects when enriched relative to the other stereoisomer(s) or when separated from the other stereoisomer(s). Additionally, the skilled artisan knows how to separate, enrich, and/or to selectively prepare said stereoisomers. Accordingly, the present invention comprises compounds selected from Formula I, TV-oxides and agriculturally suitable salts thereof. The compounds of the invention may be present as a mixture of stereoisomers, individual stereoisomers, or as an optically active form.

The compounds of Formula I wherein R⁵ is CO2H (i.e. a carboxylic acid function) are believed to be the compounds that bind to an active site on a plant enzyme or receptor causing herbicidal effect on the plant. Other compounds of Formula I wherein the substituent R is a group that can be transformed within plants or the environment to a carboxylic acid function (i.e. CO2H) provide similar herbicidal effects and are within the scope of the present invention. Therefore "a herbicidally effective derivative of CO2H" when used to describe the substituent R⁵ in Formula I is defined as any salt, ester, carboxamide, acyl hydrazide, imidate, thioimidate, amidine, acyl halide, acyl cyanide, acid anhydride, ether, acetal, orthoester, carboxaldehyde, oxime, hydrazone, thioacid, thioester, dithiolester, nitrile or any other carboxylic acid derivative known in the art which does not extinguish the herbicidal activity of the compound of Formula I and is or can be hydrolyzed, oxidized, reduced or otherwise metabolized in plants or soil to provide the carboxylic acid function, which depending upon pH, is in the dissociated or the undissociated form.

Agriculturally suitable salts of the compounds of the invention are salts formed by contact with acids or bases or through ion exchange such that the derived salts retain sufficient water solubility for bioavailability and thus herbicidal efficacy and that the counterions of the salts are suitable for use in agriculture. The agriculturally suitable salts of the compounds of the invention include acid-addition salts with inorganic or organic acids such as hydrobromic, hydrochloric, nitric, phosphoric, sulfuric, acetic, butyric, fumaric, lactic, maleic, malonic, oxalic, propionic, salicylic, tartaric, 4-toluenesulfonic or valeric acids. The agriculturally suitable salts of the compounds of the invention also include those formed with strong bases (e.g., hydroxides of sodium, potassium, lithium or quaternary ammonium) or amines. One skilled in the art recognizes that because in the environment and under physiological conditions salts of the compounds of the invention are in equilibrium with their corresponding nonsalt forms, agriculturally suitable salts share the biological utility of the nonsalt forms.

Particularly useful are agriculturally suitable salts of compounds of Formula I wherein R⁵ is CO2H formed with strong bases or amines. As is well known in the art, contact of a carboxylic acid group (CO₂H) with a base causes deprotonation to give the corresponding carboxylate ion (CO₂ ⁹) and a typically positively charged counterion derived from the base. An extensive range of counterions form agriculturally suitable salts of compounds of Formula I wherein R⁵ is CO2H, as most of the derived salts have sufficient water solubility for bioavailability. Illustrative and of particular note are salts of compounds of Formula I in which R⁵ is CO₂H wherein the counterion ion is an alkali metal cation such as lithium, sodium or potassium, quaternary ammonium such as tetramethylamrnonium, ternary sulfonium such as trimethylsulfonium, or derived from an amine such as dimethylamine, diethanolamine (diolamine), triethanolamine (trolamine).

Also particularly useful are ester and thioester derivatives of CO2H as R⁵ in the compounds of Formula I. As is well known in the art, ester groups (i.e. CO₂RAL) result from condensation of a carboxylic acid function (CO2H) with an alcohol (i.e. RALØH) wherein R^AL is the radical derived from the alcohol; a wide range of methods are known to prepare such esters. Analogously, thioester groups of formula C(O)SR^AL may be conceptually viewed as the condensation product of a carboxylic acid function with a thioalcohol (often called a mercaptan) of formula RALSH; a variety of methods are known to prepare such thioesters. As compounds of Formula I wherein R⁵ is CO2H are herbicidally active and their derived esters and thioesters are susceptible to hydrolysis (to R^ being

CO2H) particularly in the presence of hydrolytic enzymes, the compounds of Formula I wherein R⁵ is an ester (i.e. CO₂RAL) or thioester (i.e. C(O)SRAL) _are generally useful as herbicides. Of the herbicidally effective derivatives of CO2H, the ester and thioester derivatives, particularly ester derivatives, are among the most conveniently prepared and useful. If the radical RAL has more than one OH or SH function, the radical may then be condensed with more than one pyrimidine ring system of Formula I having CO2H as R⁵. As the derived multiply esterified derivatives can be hydrolyzed to the compound of Formula I having CO2H as R⁵, said multiply esterified derivatives are among the herbicidally effective derivatives of CO₂H. Illustrative and of note are ester and thioester compounds of Formula I in which R⁵ being CO2H is esterified with methanol, ethanol, butanol, 2-butoxyethanol,

2-ethylhexanol, isopropanol, 2-methylpropanol (isobutanol), octanol isomers (isoctanol) and ethanethiol to form methyl, ethyl, butyl, 2-butoxyethyl, 2-ethylhexyl, isopropyl,

2-methypropyl, isoctyl and ethylthio esters, respectively. Of particular note are the methyl and ethyl esters.

Embodiments of the present invention include: Embodiment 1. A compound of Formula I wherein R⁵ is CO₂R²⁹, CH₂OR³⁰, CH(OR³¹XOR³²), CHO, C(=NOR³³)H, C(=NNR³⁴R³⁵)H,

C(=O)N(R³⁶)R³⁷, C(=S)OR³⁸, C(=O)SR³⁹, C(=S)SR⁴⁰ or C(=NR⁴¹)YR⁴²; R²⁹ is H, -CHfC(O)O(CH₂)_m}, -N=C(R⁴³)R⁴⁴; or a radical selected from C₁-C₁₄ alkyl, 03-C₁₂ cycloalkyl, C₄-C₁₂ alkylcycloalkyl, C₄-C₁₂ cycloalkylalkyl, C2~C₁₄ alkenyl, C2~C₁₄ alkynyl and phenyl, each radical optionally substituted with 1-3 R⁴⁵; or

R²⁹ is a divalent radical linking the carboxylic ester function CO2R²⁹ of each of two pyrimidine ring systems of Formula I, the divalent radical selected from -CH2-,

-(CH₂)₂-, -(CH₂)₃- and -CH(CH₃)CH₂-;

R³⁰ is H, C₁-C₁₀ alkyl optionally substituted with 1-3 R⁴⁶, or benzyl; R³¹ and R³² are independently C₁-C₄ alkyl or C₁-C₃ haloalkyl; or R³¹ and R³² are taken together as -CH₂CH₂-, -CH₂CH(CH₃)- or -(CH₂)₃-;

R³³ is H, C₁-C₄ alkyl, C₁-C₄ haloalkyl or benzyl;

R³⁴ is H, C₁-C₄ alkyl, C₁-C₄ haloalkyl, C₂-C₄ alkylcarbonyl, C₂-C₄ alkoxycarbonyl or benzyl; R³⁵ is H, C₁-C₄ alkyl or C₁-C₄ haloalkyl;

R³⁶ is H, C₁-C₄ alkyl, hydroxy, C₁-C₄ alkoxy or S(O)₂R⁴⁷; R³⁷ is H or C₁-C₄ alkyl;

R³⁸, R³⁹ and R⁴⁰ are H; or a radical selected from C₁-C₁₄ alkyl, C₃-C₁₂ cycloalkyl, C₄-C₁₂ alkylcycloalkyl, C₄-C₁₂ cycloalkylalkyl, C₂-C₁₄ alkenyl and C₂-C₁₄ alkynyl, each radical optionally substituted with 1-3 R⁴⁵;

Y is O, S or NR⁴⁸;

R⁴¹ is H, C₁-C₃ alkyl, C₁-C₃ haloalkyl, C₂-C₄ alkoxyalkyl, OH or C₁-C₃ alkoxy; R⁴² is C₁-C₃ alkyl, C₁-C₃ haloalkyl or C₂-C₄ alkoxyalkyl; or R⁴¹ and R⁴² are taken together as -(CH₂)₂-, -CH₂CH(CH₃)- or -(CH₂)₃-; R⁴³ and R⁴⁴ are independently C _J-C₄ alkyl; each R⁴⁵ is independently halogen, cyano, hydroxycarbonyl, C₂-C₄ alkoxycarbonyl, hydroxy, C₁-C₄ alkoxy, C₁-C₄ haloalkoxy, C₁-C₄ alkylthio, C₁-C₄ haloalkylthio, amino, C₁-C₄ alkylamino, C₂-C₄ dialkylamino, -CH£O(CH₂)_n} or phenyl optionally substituted with 1-3 R⁴⁹; or two R⁴⁵ are taken together as -OC(O)O- or -O(C(R⁵⁰)(R⁵⁰))₁_₂O-; or two R⁴⁵ are taken together as an oxygen atom to form, with the carbon atom to which they are attached, a carbonyl moiety; each R⁴⁶ is independently halogen, C₁-C₄ alkoxy, C₁-C₄ haloalkoxy, C₁-C₄ alkylthio, C₁-C₄ haloalkylthio, amino, C₁-C₄ alkylamino or C₂-C₄ dialkylamino; or two R⁴⁶ are taken together as an oxygen atom to form, with the carbon atom to which they are attached, a carbonyl moiety; R⁴⁷ is C₁-C₄ alkyl, C₁-C₃ haloalkyl or NR⁵¹R^²; R⁴⁸ is H, C₁-C₃ alkyl, C₁-C₃ haloalkyl or C₂-C₄ alkoxyalkyl; each R⁴⁹ is independently halogen, C₁-C₄ alkyl, C₁-C₃ haloalkyl, hydroxy, C₁-C₄ alkoxy, C₁-C₃ haloalkoxy, C₁-C₃ alkylthio, C₁-C₃ haloalkylthio, amino, C₁-C₃ alkylamino, C₂-C₄ dialkylamino or nitro; each R⁵⁰ is independently selected from H and C₁-C₄ alkyl; R⁵¹ and R⁵² are independently H or C₁-C₄ alkyl; m is an integer from 2 to 3; and n is an integer from 1 to 4.

Embodiment 2. A compound of Embodiment 1 wherein R⁵ is CO₂R²⁹, CH₂OR³⁰ or CHO. Embodiment 3. A compound of Embodiment 2 wherein R⁵ is CO2R²⁹ or CHO. Embodiment 4. A compound of Embodiment 3 wherein R⁵ is CO2R²⁹. Embodiment 5. A compound of Embodiment 1 wherein R²⁹ is H, Ci-Cg alkyl or

C_j alkyl substituted with phenyl optionally substituted with 1-3 R⁴⁵. Embodiment 6. A compound of Embodiment 5 wherein R²⁹ is H, C1-C4 alkyl or

Ci alkyl substituted with phenyl optionally substituted with 1-3 R⁴⁵. Embodiment 7. A compound of Embodiment 6 wherein R²⁹ is H, C1-C4 alkyl or benzyl.

Embodiment 8. A compound of Embodiment 1 wherein R³^ is H, C1-C4 alkyl, hydroxy or C_j-C₄ alkoxy.

Embodiment 9. A compound of Embodiment 1 wherein R⁴¹ is H, Ci- C3 alkyl, Ci- C3 haloalkyl or C2-C4 alkoxyalkyl. Embodiment 10. A compound of Formula I wherein R⁵ is CO2H, an agriculturally suitable salt or an ester or thioester derivative thereof. Embodiment 11. A compound of Embodiment 10 wherein R⁵ is CO2H, an agriculturally suitable salt or an ester derivative thereof.

Embodiment 12. A compound of Formula I wherein p is an integer from 0 to 2. Embodiment 13. A compound of Embodiment 12 wherein p is an integer from 0 to 1. Embodiment 14. A compound of Embodiment 13 wherein p is 0. Embodiment 15. A compound of Formula I wherein R¹ is H or F.

Embodiment 16. A compound of Formula I wherein R¹ is F or Cl. Embodiment 17. A compound of Formula I wherein R¹ is H. Embodiment 18. A compound of Formula I wherein R¹ is F. Embodiment 19. A compound of Formula I wherein R¹ is Cl. Embodiment 20. A compound of Formula I wherein R² is H, C(O)R¹⁰ or C₁-C₄ alkyl optionally substituted with R⁷; R³ is H or C1-C2 alkyl; or R² and R³ are taken together as =C(R¹⁹)N(R²⁰)R²¹. Embodiment 21. A compound of Embodiment 20 wherein R² is H, CH3 or C(O)R¹⁰;

R³ is H or CH₃; or R² and R³ are taken together as =C(R¹9)N(R²⁰)R²¹. Embodiment 22. A compound of Embodiment 20 wherein R² is H, C(O)CH₃ or

Ci-C₄ alkyl optionally substituted with R⁷; and R³ is H or Ci-C₂ alkyl. Embodiment 23. A compound of Embodiment 22 wherein R² and R³ are independently

H or methyl.

Embodiment 24. A compound of Embodiment 23 wherein R² and R³ are H. Embodiment 25. A compound of Formula I wherein R⁴ is Br or Cl.

Embodiment 26. A compound of Embodiment 24 wherein R⁴ is Cl. Embodiment 27. A compound of Formula I wherein each R^ is independently halogen,

C_nC₂ alkyl or C_nC₂ haloalkyl. Embodiment 28. A compound of Formula I wherein R⁷ is halogen, methoxy, Cj fluoroalkoxy, methylthio, Cj fluoroalkylthio, amino, methylamino, dimethylamino or methoxycarbonyl.

Embodiment 29. A compound of Formula I wherein R¹⁰ is H or C₁-C3 alkyl. Embodiment 30. A compound of Embodiment 29 wherein R¹⁰ is H or CH₃.

Embodiment 31. A compound of Embodiment 30 wherein R¹⁰ is CH3. Embodiment 32. A compound of Formula I wherein R¹⁹ is H or C₁-C₂ alkyl. Embodiment 33. A compound of Embodiment 32 wherein R'⁹ is H or CH3. Embodiment 34. A compound of Formula I wherein R²⁰ and R²¹ are independently H or C₁-C₂ alkyl.

Embodiment 35. A compound of Formula I wherein R²⁰ and R²¹ are independently H or CH₃.

Included for the compounds of the described Embodiments are N-oxides and agriculturally suitable salts thereof. Combinations of Embodiments 1-35 are illustrated by:

Embodiment A. A compound of Formula I wherein R⁵ is CO₂R²⁹, CH₂OR³⁰, CH(OR³¹XOR³²), CHO, C(=NOR³³)H, C(=NNR³⁴R³⁵)H,

C(=O)N(R³⁶)R³⁷, C(=S)OR³8, C(=O)SR³⁹, C(=S)SR40 or C(=NR⁴¹)YR⁴²;

R²⁹ is H, -CHfC(O)O(CH₂)_m}, -N=C(R⁴³)R⁴⁴; or a radical selected from C₁-C₁₄ alkyl, C₃-C₁₂ cycloalkyl, C₄-C₁₂ alkylcycloalkyl, C₄-C₁₂ cycloalkylalkyl,

C₂-C₁₄ alkenyl, C₂-C₁₄ alkynyl and phenyl, each radical optionally substituted with 1-3 R⁴⁵; or

R²⁹ is a divalent radical linking the carboxylic ester function CO₂R²⁹ of each of two pyrimidine ring systems of Formula I, the divalent radical selected from -CH₂-, -(CH₂)₂-, -(CH₂)₃- and -CH(CH₃)CH₂-;

R³⁰ is H, C₁-C₁₀ alkyl optionally substituted with 1-3 R⁴⁶, or benzyl; R³¹ and R³² are independently C_j-C₄ alkyl or C₁-C₃ haloalkyl; or R³¹ and R³² are taken together as -CH₂CH₂-, -CH₂CH(CH₃)- or -(CH₂)₃-; R³³ is H, C₁-C₄ alkyl, C₁-C₄ haloalkyl or benzyl; R³⁴ is H, C₁-C₄ alkyl, C₁-C₄ haloalkyl, C₂-C₄ alkylcarbonyl, C₂-C₄ alkoxycarbonyl or benzyl;

R³⁵ is H, C₁-C₄ alkyl or C₁-C₄ haloalkyl; R³⁶ is H, C₁-C₄ alkyl, hydroxy, C₁-C₄ alkoxy or S(O)₂R⁴⁷; R³⁷ is H or C₁-C₄ alkyl; R³⁸, R³⁹ and R⁴⁰ are H; or a radical selected from C₁-C₁₄ alkyl, C₃-C₁₂ cycloalkyl,

C₄-C₁₂ alkylcycloalkyl, C₄-C₁₂ cycloalkylalkyl, C₂-C₁₄ alkenyl and C₂-C₁₄ alkynyl, each radical optionally substituted with 1-3 R⁴⁵; Y is O, S or NR⁴⁸; R⁴¹ is H, C₁-C₃ alkyl, C₁-C₃ haloalkyl, C₂-C₄ alkoxyalkyl, OH or C₁-C₃ alkoxy; R⁴² is C₁-C₃ alkyl, C₁-C₃ haloalkyl or C₂-C₄ alkoxyalkyl; or R⁴¹ and R⁴² are taken together as -(CH₂)₂-, -CH₂CH(CH₃)- or -(CH₂)₃-; R⁴³ and R⁴⁴ are independently C₁-C₄ alkyl; each R⁴⁵ is independently halogen, cyano, hydroxycarbonyl, C₂-C₄ alkoxycarbonyl, hydroxy, C₁-C₄ alkoxy, C₁-C₄ haloalkoxy, C₁-C₄ alkylthio, C₁-C₄ haloalkylthio, amino, C₁-C₄ alkylamino, C₂-C₄ dialkylamino, -CH£O(CH₂)_π} or phenyl optionally substituted with 1-3 R⁴⁹; or two R⁴⁵ are taken together as -OC(O)O- or -0(C(R⁵⁰XR⁵⁰X)_1-2O-; or two R⁴⁵ are taken together as an oxygen atom to form, with the carbon atom to which they are attached, a carbonyl moiety; each R⁴⁶ is independently halogen, C₁-C₄ alkoxy, C₁-C₄ haloalkoxy, C₁-C₄ alkylthio, C₁-C₄ haloalkylthio, amino, C₁-C₄ alkylamino or C₂-C₄ dialkylamino; or two R⁴⁶ are taken together as an oxygen atom to form, with the carbon atom to which they are attached, a carbonyl moiety; R⁴⁷ is C₁-C₄ alkyl, C₁-C₃ haloalkyl Or NR⁵¹R⁵²; R⁴⁸ is H, C₁-C₃ alkyl, C₁-C₃ haloalkyl or C₂-C₄ alkoxyalkyl; each R⁴⁹ is independently halogen, C₁-C₄ alkyl, C₁-C₃ haloalkyl, hydroxy, C₁-C₄ alkoxy, C₁-C₃ haloalkoxy, C₁-C₃ alkylthio, C₁-C₃ haloalkylthio, amino, C₁-C₃ alkylamino, C₂-C₄ dialkylamino or nitro; each R⁵⁰ is independently selected from H and C₁-C₄ alkyl; R⁵¹ and R⁵² are independently H or C₁-C₄ alkyl; m is an integer from 2 to 3; and n is an integer from 1 to 4.

Embodiment B. A compound of Embodiment A wherein p is 0.

Embodiment C. A compound of Embodiment B wherein R⁵ is CO₂R²⁹, CH₂OR-³⁰ or

CHO.

Embodiment D. A compound of Embodiment B wherein R² is H, CH₃ or C(O)R¹⁰; R³ is H or CH₃ ; or R² and R³ are taken together as =C(R^{! 9})N(R²⁰)R²¹ ; and R¹ °,

R¹⁹, R²⁰ and R²¹ are each independently H or CH₃. Embodiment E. A compound of Embodiment D wherein R⁵ is CO₂R²⁹; and R² and R³ are H.

Embodiment F. A compound of Embodiment E wherein R²⁹ is H, C₁-C₄ alkyl or benzyl.

Specific embodiments include compounds of Formula I selected from the group consisting of: methyl 4-amino-3, 5 -dichloro-6-cyclopropyl-2-pyridinecarboxylate, . _

12

4-amino-3,5-dichloro-6-cyclopropyl-2-pyridinecarboxylic acid, methyl 4-amino-3-chloro-6-cyclopropyl-2-pyridinecarboxylate, 4-amino-3-chloro-6-cyclopropyl-2-pyridinecarboxylic acid, methyl 4-amino-3-chloro-6-cyclopropyl-5-fluoro-2-pyridinecarboxylate, and 4-amino-3-chloro-6-cyclopropyl-5-fluoro-2-pyridinecarboxylic acid.

Also noteworthy as embodiments are herbicidal compositions of the present invention comprising the compounds of embodiments described above.

This invention also relates to a method for controlling undesired vegetation comprising applying to the locus of the vegetation herbicidally effective amounts of the compounds of the invention (e.g., as a composition described herein). Of note as embodiments relating to methods of use are those involving the compounds of embodiments described above.

The compounds of Formula I can be prepared by one or more of the following methods and variations as described in Schemes 1-3. The definitions of R¹, R², R³, R⁴, R⁵, R⁶ and p in the compounds of Formulae 1-4 below are as defined above in the Summary of the Invention unless otherwise indicated.

Compounds of Formula I can be prepared from compounds of Formula 2 wherein X¹ is a leaving group such as a halogen or a (halo)alkylsulfonate (e.g., trifluoromethanesulfonate) as outlined in Scheme 1. The method of Scheme 1 is illustrated in Step B of Example 1. Scheme 1

catalyst

wherein M¹ is B(OH)₂, Sn(«-Bu)3, MgX¹ or ZnX¹; and X¹ is a leaving group.

This method involves transition metal-catalyzed reaction of a compound of Formula 2 with a compound of Formula 3 in the form of a boronic acid (e.g., M¹ is B(OFf^), an organotin reagent (e.g., M¹ is Sn(H-Bu^), a Grignard reagent (e.g., M¹ is MgX¹) or an organozinc reagent (e.g., M¹ is ZnX¹). (For example see: N. AIi, A. McKillop, M. Mitchell, R. Rebelo, A. Ricardo, P. Wallbank, Tetrahedron, 1992, 48, 8117-8126; D. Wallace, C-Y. Chen, Tetrahedron Lett. 2002, 43, 6987-6990; M.-L. Yao, M.-Z. Deng, Synthesis 2000, 1095- 1100; M. Yao, J. Wang, M. Deng, Chinese Science Bulletin 2001, 48, 1277-1281; J. Solberg, K. Undheim, Acta Chem. Scand. 1989, 43, 62-68; S. Wiedemann, K. Rauch, A. Savchenko, I. Marek, A. deMeijere, Eur. J. Org. Chem. 2004, 631-635; V. Bonnet, F. Mongin, F. Trecourt, G. Queguiner and P. Knochel, Tetrahedron 2002, 58, 4429-4438; N. Utrecht, Syn. Comm. 1998, 28, 225-232.)

The compounds of Formula 2 can be prepared by a variety of methods such as those disclosed in PCT Patent Publications WO 2004/089906, WO 2003/011853, 5 WO 2001/051684 and WO 2001/051468.

Alternatively compounds of Formula I can be prepared from compounds of Formula 4 by halogenation with a reagent such as a 7V-halosuccinimide or bromine (when R⁴ is Br) or chlorine (when R⁴ is Cl) or a N-fluoroammonium compound (e.g., l-chloromethyl-4-fiuoro- l,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate or Λ^-difiuorobipyridinium 10 tetrafluoroborate, when R⁴ is F) in a variety of solvents such as jVJV-dimethylformamide, acetonitrile or water as outlined in Scheme 2. In instances wherein R¹ is H a mixture of compounds may be obtained. The method of Scheme 2 is illustrated in Step A of Example 2.

Scheme 2

halogenation reagent

Compounds of Formula 4 wherein R¹ is H may be obtained from compounds of Formula I wherein R¹ and R⁴ are halogen by a reduction method such as hydrogenation as shown in Scheme 3. The method of Scheme 3 is illustrated in Step B of Example 2.

Scheme 3 hydrogen

I (where R¹ and R⁴ are halogen) ► 4 (where R ' is H)

~rv catalyst

It is recognized that some reagents and reaction conditions described above for preparing compounds of Formula I may not be compatible with certain functionalities present in the intermediates, hi these instances, the incorporation of protection/deprotection sequences or functional group interconversions into the synthesis will aid in obtaining the

25 desired products. The use and choice of the protecting groups will be apparent to one skilled in chemical synthesis (see, for example, Greene, T. W.; Wuts, P. G. M. Protective Groups in Organic Synthesis, 2nd ed.; Wiley: New York, 1991). One skilled in the art will recognize that, in some cases, after the introduction of a given reagent as it is depicted in any individual scheme, it may be necessary to perform additional routine synthetic steps not

30 described in detail to complete the synthesis of compounds of Formula I. One skilled in the art will also recognize that it may be necessary to perform a combination of the steps illustrated in the above schemes in an order other than that implied by the particular sequence presented to prepare the compounds of Formula I.

One skilled in the art will also recognize that compounds of Formula I and the intermediates described herein can be subjected to various electrophilic, nucleophilic, radical, organometallic, oxidation, and reduction reactions to add substituents or modify existing substituents.

Without further elaboration, it is believed that one skilled in the art using the preceding description can utilize the present invention to its fullest extent. The following Examples are, therefore, to be construed as merely illustrative, and not limiting of the disclosure in any way whatsoever. Steps in the following Examples illustrate a procedure for each step in an overall synthetic transformation, and the starting material for each step may not have necessarily been prepared by a particular preparative run whose procedure is described in other Examples or Steps. Percentages are by weight except for chromatographic solvent mixtures or where otherwise indicated. Parts and percentages for chromatographic solvent mixtures are by volume unless otherwise indicated. MPLC means medium pressure chromatography on silica gel. ¹H NMR spectra are reported in ppm downfield from tetramethylsilane; "s" means singlet, "d" means doublet, "t" means triplet, "q" means quartet, "m" means multiplet, "dd" means doublet of doublets, "dt" means doublet of triplets, "br s" means broad singlet.

EXAMPLE 1

Preparation of methyl 4-amino-3,5-dichloro-6-cyclopropyl-2-pyridinecarboxylate

(Compound 1)

Step A: Preparation of methyl 4-amino-3,5,6-trichloro-2-pyridinecarboxylate To a solution of 4-amino-3,5,6-trichloro-2-pyridinecarboxylic acid (2.75 g, 10.8 mmol) in N,7V-dimethylformamide (30 mL) was added lithium carbonate (1.03 g, 14 mmol) and iodomethane (0.87 mL, 14 mmol). The reaction mixture was heated at 60 °C overnight.

After the reaction mixture was cooled the volatiles were removed using a rotary evaporator.

The residue was portioned between ethyl acetate and water. The organic layer was dried and the solvent was removed with a rotary evaporator to afford the title compound as a yellow solid (2.63 g).

¹H NMR (CDCl₃) δ 5.40 (br s, 2H), 3.97 (s, 3H).

Step B: Preparation of methyl 4-amino-3,5-dichloro-6-cyclopropyl-2-pyridine- carboxylate To a solution of methyl 4-arnino-3,5,6-trichloro-2-pyridinecarboxylate (i.e. the product of Step A) (2.63 g, 9.8 mmol) in benzene (80 mL) was added cyclopropylboronic acid (1.03 g, 12 mmol), potassium phosphate (7.2 g, 34 mmol), palladium(II) acetate (0.107 g, 0.48 mmol), tricyclohexyl phosphine (0.27 g, 0.96 mmol) and water (2.4 mL). The reaction mixture was refluxed overnight. After cooling, the reaction mixture was partitioned between ethyl acetate and water. The organic layer was dried and the solvent was removed with a rotary evaporator. The residue was purified by MPLC (10→35% ethyl acetate in hexanes as eluant) to afford the title compound as a white solid (0.47 g) melting at 125-126 ⁰C.

¹H NMR (CDCl₃) 8 5.09 (br s, 2H), 3.94 (s, 3H), 2.08 (m, IH), 0.98 (m, 2H), 0.92 (m, 2H).

EXAMPLE 2 Preparation of methyl 4-amino-3-chloro-6-cyclopropyl-2-pyridinecarboxylate (Compound 2)

Step A: Preparation of methyl 4-amino-6-cyclopropyl-2-pyridinecarboxylate A mixture of methyl 4-amino-3,5-dichloro-6-cyclopropyl-2-pyridinecarboxylate (i.e. the product of Example 1) (0.10 g, 0.38 mmol)) and 10% palladium on carbon (0.04 g) in ethanol (20 mL) was shaken under 50 psi (345 kPa) pressure of hydrogen for 4 h. Triethylamine (0.13 mL, 0.93 mmol) was added. The reaction mixture was filtered through Celite® diatomaceous filter aid. The solvent was removed with a rotary evaporator. The residue was taken up in ethyl acetate and was washed with water. The organic layer was dried, and the solvent was removed with a rotary evaporator. The residue was purified by MPLC (25→75% ethyl acetate in hexanes as eluant) to afford the title compound as a white solid (0.037 g).

¹H NMR (CDCl₃) δ 7.21 (s, IH), 6.35 (s, IH), 4.35 (br s, 2H), 3.95 (s, 3H), 2.37 (m, IH), 1.09 (m, 2H), 0.98 (m, 2H).

Step B: Preparation of methyl 4-amino-3-chloro-6-cyclopropyl-2-pyridinecarboxylate

Methyl 4-amino-6-cyclopropyl-2-pyridinecarboxylate (i.e. the product of Step A) (0.037 g, 0.19 mmol) was dissolved in Ny/V-dimethylformamide (2 mL). N-chloro- succinimide (0.026 g, 0.19 mmol) was added. The reaction mixture was heated to 60 °C for 4 h. After cooling the solvent was removed with a rotary evaporator. The residue was purified by MPLC (15→3O% ethyl acetate in hexanes as eluant) to afford the title compound as a white solid (0.006 g) melting at 100-103 °C. ¹H NMR (CDCl₃) δ 6.46 (s, IH) 4.7 (br s, 2H), 3.91 (s, 3H) 1.94 (m, IH), 0.94 (m, 4H).

Also isolated was methyl 4-amino-5-chloro-6-cyclopropyl-2-pyridinecarboxylate (0.018 g).

¹H NMR (CDCl₃) δ 7.31 (s, IH) 4.61 (br s, 2H), 3.91 (s, 3H) 2.44 (m, IH), 1.15 (m, 2H), 1.03 (m, 2H).

By the procedures described herein together with methods known in the art, the following compounds of Tables 1 to 3 can be prepared. The following abbreviations are used in the Tables which follow, t means tertiary, s means secondary, n means normal, / means iso, c means cyclo, Me means methyl, Et means ethyl, Pr means propyl, /-Pr means isopropyl. "^θ" means negative formal charge, and "^® means positive formal charge.

TABLE 2

is Cl. is Cl. is Br

IsF.

is I. is I. is I.

TABLE 3

=CHN(Me)₂

Formulation/Utility

Compounds of this invention will generally be used as a formulation or composition with an agriculturally suitable carrier comprising at least one of a liquid diluent, a solid diluent or a surfactant. The formulation or composition ingredients are selected to be consistent with the physical properties of the active ingredient, mode of application and environmental factors such as soil type, moisture and temperature. Useful formulations include liquids such as solutions (including emulsifiable concentrates), suspensions, emulsions (including microemulsions and/or suspoemulsions) and the like which optionally can be thickened into gels. Useful formulations further include solids such as dusts, powders, granules, pellets, tablets, films (including seed coatings), and the like which can be water-dispersible ("wettable") or water-soluble. Active ingredient can be (micro)encapsulated and further formed into a suspension or solid formulation; alternatively the entire formulation of active ingredient can be encapsulated (or "overcoated"). Encapsulation can control or delay release of the active ingredient. Sprayable formulations can be extended in suitable media and used at spray volumes from about one to several hundred liters per hectare. High-strength compositions are primarily used as intermediates for further formulation.

The formulations will typically contain effective amounts of active ingredient, diluent and surfactant within the following approximate ranges which add up to 100 percent by weight.

Weight Percent

Active Ingredient Diluent Surfactant

Water-Dispersible and Water- 0.001-90 0-99.999 0-15 soluble Granules, Tablets and Powders.

Suspensions, Emulsions, 1-50 40-99 0-50 Solutions (including Emulsifiable Concentrates)

Dusts 1-25 70-99 0-5

Granules and Pellets 0.001-99 5-99.999 0-15

High Strength Compositions 90-99 0-10 0-2

Typical solid diluents are described in Watkins, et al., Handbook of Insecticide Dust Diluents and Carriers, 2nd Ed., Dorland Books, Caldwell, New Jersey. Typical liquid diluents are described in Marsden, Solvents Guide, 2nd Ed., Interscience, New York, 1950. !

20

McCutcheon 's Detergents and Emulsifiers Annual, Allured Publ. Corp., Ridgewood, New Jersey, as well as Sisely and Wood, Encyclopedia of Surface Active Agents, Chemical Publ. Co., Inc., New York, 1964, list surfactants and recommended uses. All formulations can contain minor amounts of additives to reduce foam, caking, corrosion, microbiological growth and the like, or thickeners to increase viscosity.

Surfactants include, for example, polyethoxylated alcohols, polyethoxylated alkylphenols, polyethoxylated sorbitan fatty acid esters, dialkyl sulfosuccinates, alkyl sulfates, alkylbenzene sulfonates, organosilicones, 7V,N-dialkyltaurates, lignin sulfonates, naphthalene sulfonate formaldehyde condensates, polycarboxylates, glycerol esters, poly- oxyethylene/polyoxypropylene block copolymers, and alkylpolyglycosides where the number of glucose units, referred to as degree of polymerization (D.P.), can range from 1 to 3 and the alkyl units can range from C6 to Cγ_$ (see Pure and Applied Chemistry 72, 1255- 1264). Solid diluents include, for example, clays such as bentonite, montmorillonite, attapulgite and kaolin, starch, sugar, silica, talc, diatomaceous earth, urea, calcium carbonate, sodium carbonate and bicarbonate, and sodium sulfate. Liquid diluents include, for example, water, iV^V-dimethylformamide, dimethyl sulfoxide, N-alkylpyrrolidone, ethylene glycol, polypropylene glycol, propylene carbonate, dibasic esters, paraffins, alkylbenzenes, alkylnaphthalenes, glycerine, triacetine, oils of olive, castor, linseed, rung, sesame, corn, peanut, cotton-seed, soybean, rape-seed and coconut, fatty acid esters, ketones such as cyclohexanone, 2-heptanone, isophorone and 4-hydroxy-4-methyl-2-pentanone, acetates such as hexyl acetate, heptyl acetate and octyl acetate, and alcohols such as methanol, cyclohexanol, decanol, benzyl and tetrahydrofurfuryl alcohol.

Useful formulations of this invention may also contain materials well known to those skilled in the art as formulation aids such as antifoams, film formers and dyes. Antifoams can include water dispersible liquids comprising polyorganosiloxanes like Rhodorsil® 416. The film formers can include polyvinyl acetates, polyvinyl acetate copolymers, polyvinylpyrrolidone-vinyl acetate copolymer, polyvinyl alcohols, polyvinyl alcohol copolymers and waxes. Dyes can include water dispersible liquid colorant compositions like Pro-lzed® Colorant Red. One skilled in the art will appreciate that this is a non-exhaustive list of formulation aids. Suitable examples of formulation aids include those listed herein and those listed in McCutcheon 's 2001, Volume 2: Functional Materials published by MC Publishing Company and PCT Publication WO 03/024222.

Solutions, including emulsifiable concentrates, can be prepared by simply mixing the ingredients. Dusts and powders can be prepared by blending and, usually, grinding as in a hammer mill or fluid-energy mill. Suspensions are usually prepared by wet-milling; see, for example, U.S. 3,060,084. Granules and pellets can be prepared by spraying the active material upon preformed granular carriers or by agglomeration techniques. See Browning, "Agglomeration", Chemical Engineering, December 4, 1967, pp 147-48, Perry's Chemical Engineer's Handbook, 4th Ed., McGraw-Hill, New York, 1963, pages 8-57 and following, and WO 91/13546. Pellets can be prepared as described in U.S. 4,172,714. Water-dispersible and water-soluble granules can be prepared as taught in U.S. 4,144,050, U.S. 3,920,442 and DE 3,246,493. Tablets can be prepared as taught in U.S. 5,180,587, U.S. 5,232,701 and U.S. 5,208,030. Films can be prepared as taught in GB 2,095,558 and U.S. 3,299,566.

For further information regarding the art of formulation, see T. S. Woods, "The Formulator's Toolbox - Product Forms for Modern Agriculture" in Pesticide Chemistry and Bioscience, The Food-Environment Challenge, T. Brooks and T. R. Roberts, Eds., Proceedings of the 9th International Congress on Pesticide Chemistry, The Royal Society of Chemistry, Cambridge, 1999, pp. 120-133. See also U.S. 3,235,361, Col. 6, line 16 through Col. 7, line 19 and Examples 10-41; U.S. 3,309,192, Col. 5, line 43 through Col. 7, line 62 and Examples 8, 12, 15, 39, 41, 52, 53, 58, 132, 138-140, 162-164, 166, 167 and 169-182; U.S. 2,891,855, Col. 3, line 66 through Col. 5, line 17 and Examples 1-4; Klingman, Weed Control as a Science, John Wiley and Sons, Inc., New York, 1961, pp 81-96; Hance et al., Weed Control Handbook, 8th Ed., Blackwell Scientific Publications, Oxford, 1989; and Developments in formulation technology, PJB Publications, Richmond, UK, 2000.

In the following Examples, all percentages are by weight and all formulations are prepared in conventional ways. Compound numbers refer to compounds in Index Table A. Example A

High Strength Concentrate

Compound 1 98.5% silica aerogel 0.5% synthetic amorphous fine silica 1.0%. Example B Wettable Powder

Compound 2 65.0% dodecylphenol polyethylene glycol ether 2.0% sodium ligninsulfonate 4.0% sodium silicoaluminate 6.0% montmorillonite (calcined) 23.0%.

Example C Granule

Compound 1 10.0% attapulgite granules (low volatile matter,

0.71/0.30 mm; U.S.S. No. 25-50 sieves) 90.0%. I

22

Example D Aqueous Suspension

Compound 2 25.0% hydrated attapulgite 3.0% crude calcium ligninsulfonate 10.0% sodium dihydrogen phosphate 0.5% water 61.5%.

Example E Extruded Pellet Compound 1 25.0% anhydrous sodium sulfate 10.0% crude calcium ligninsulfonate 5.0% sodium alkylnaphthalenesulfonate 1.0% calcium/magnesium bentonite 59.0%. Example F

Microemulsion

Compound 2 1.0% triacetine 30.0%

C₈-C₁₀ alkylpolyglycoside 30.0% glyceryl monooleate 19.0% water 20.0%.

Test results indicate that the compounds of the present invention are highly active preemergent and/or postemergent herbicides and/or plant growth regulants. Many of them have utility for broad-spectrum pre- and/or postemergence weed control in areas where complete control of all vegetation is desired such as around fuel storage tanks, industrial storage areas, parking lots, drive-in theaters, air fields, river banks, irrigation and other waterways, around billboards and highway and railroad structures. Many of the compounds of this invention, by virtue of selective metabolism in crops versus weeds, or by selective activity at the locus of physiological inhibition in crops and weeds, or by selective placement on or within the environment of a mixture of crops and weeds, are useful for the selective control of grass and broadleaf weeds within a crop/weed mixture. One skilled in the art will recognize that the preferred combination of these selectivity factors within a compound or group of compounds can readily be determined by performing routine biological and/or biochemical assays. Compounds of this invention may show tolerance to important agronomic crops including, but is not limited to, alfalfa, barley, cotton, wheat, rape, sugar beets, corn (maize), sorghum, soybeans, rice, oats, peanuts, vegetables, tomato, potato, perennial plantation crops including coffee, cocoa, oil palm, rubber, sugarcane, citrus, grapes, fruit trees, nut trees, banana, plantain, pineapple, hops, tea and forests such as eucalyptus and conifers (e.g., loblolly pine), and turf species (e.g., Kentucky bluegrass, St. Augustine grass, Kentucky fescue and Bermuda grass). Compounds of this invention can be used in crops genetically transformed or bred to incorporate resistance to herbicides, express proteins toxic to invertebrate pests (such as Bacillus thuringiensis toxin), and/or express other useful traits. Those skilled in the art will appreciate that not all compounds are equally effective against all weeds. Alternatively, the subject compounds are useful to modify plant growth.

As the compounds of the invention have both preemergent and postemergent herbicidal activity, to control undesired vegetation by killing or injuring the vegetation or reducing its growth, the compounds can be usefully applied by a variety of methods involving contacting a herbicidally effective amount of a compound of the invention, or a composition comprising said compound and at least one of a surfactant, a solid diluent or a liquid diluent, to the foliage or other part of the undesired vegetation or to the environment of the undesired vegetation such as the soil or water in which the undesired vegetation is growing or which surrounds the seed or other propagule of the undesired vegetation.

A herbicidally effective amount of the compounds of this invention is determined by a number of factors. These factors include: formulation selected, method of application, amount and type of vegetation present, growing conditions, etc. hi general, a herbicidally effective amount of compounds of this invention is about 0.0001 to 20 kg/ha with a preferred range of about 0.001 to 5 kg/ha and a more preferred range of about 0.004 to 3 kg/ha. One skilled in the art can easily determine the herbicidally effective amount necessary for the desired level of weed control.

Compounds of this invention can be used alone or in combination with other herbicides, insecticides and fungicides, and other agricultural chemicals such as fertilizers. Mixtures of the compounds of the invention with other herbicides can broaden the spectrum of activity against additional weed species, and suppress the proliferation of any resistant biotypes. A mixture of one or more of the following herbicides with a compound of this invention may be particularly useful for weed control: acetochlor, acifluorfen and its sodium salt, aclonifen, acrolein (2-propenal), alachlor, alloxydim, ametryn, amicarbazone, amidosulfuron, aminopyralid, amitrole, ammonium sulfamate, anilofos, asulam, atrazine, azimsulfuron, beflubutamid, benazolin, benazolin-ethyl, bencarbazone, benfluralin, benfuresate, bensulfuron-methyl, bensulide, bentazone, benzobicyclon, benzofenap, bifenox, bilanafos, bispyribac and its sodium salt, bromacil, bromobutide, bromofenoxim, bromoxynil, bromoxynil octanoate, butachlor, butafenacil, butamifos, butralin, butroxydim, butylate, cafenstrole, carbetamide, carfentrazone-ethyl, catechin, chlomethoxyfen, chloramben, chlorbromuron, chlorflurenol-methyl, chloridazon, chlorimuron-ethyl, chlorotoluron, chlorpropham, chlorsulfuron, chlorthal-dimethyl, chlorthiamid, cinidon-ethyl, cinmethylin, cinosulfiiron, clethodim, clodinafop-propargyl, clomazone, clomeprop, clopyralid, clopyralid-olamine, cloransulam-methyl, CUH-35 (2-methoxyethyl 2-[[[4-chloro- 2-fluoro-5-[(l -methyl-2-propynyl)oxy]phenyl](3-fluorobenzoyl)amino]carbonyl]- 1 - cyclohexene-1-carboxylate), cumyluron, cyanazine, cycloate, cyclosulfamuron, cycloxydim, cyhalofop-butyl, 2,4-D and its butotyl, butyl, isoctyl and isopropyl esters and its dimethylammonium, diolamine and trolamine salts, daimuron, dalapon, dalapon-sodium, dazomet, 2,4-DB and its dimethylammonium, potassium and sodium salts, desmedipham, desmetryn, dicamba and its diglycolammonium, dimethylammonium, potassium and sodium salts, dichlobenil, dichlorprop, diclofop-methyl, diclosulam, difenzoquat metilsulfate, diflufenican, diflufenzopyr, dimefuron, dimepiperate, dimethachlor, dimethametryn, dimethenamid, dimethenamid-P, dimethipin, dimethylarsinic acid and its sodium salt, dinitramine, dinoterb, diphenamid, diquat dibromide, dithiopyr, diuron, DNOC, endothal, EPTC, esprocarb, ethalfluralin, ethametsulfuron-methyl, ethofumesate, ethoxyfen, ethoxysulfuron, etobenzanid, fenoxaprop-ethyl, fenoxaprop-P-ethyl, fentrazamide, fenuron, fenuron-TCA, flamprop-methyl, flamprop-M-isopropyl, flamprop-M-methyl, flazasulfuron, florasulam, fluazifop-butyl, fluazifop-P -butyl, flucarbazone, fluchloralin, flufenacet, flufenpyr, flufenpyr-ethyl, flumetsulam, flumiclorac-pentyl, flumioxazin, fluometuron, fluoroglycofen-ethyl, flupyrsulfuron-methyl and its sodium salt, flurenol, flurenol-butyl, fluridone, flurochloridone, fluroxypyr, flurtamone, fluthiacet-methyl, fomesafen, foramsulfuron, fosamine-ammonium, glufosinate, glufosinate-ammonium, glyphosate and its salts such as ammonium, isopropylammonium, potassium, sodium (including sesquisodium) and trimesium (alternatively named sulfosate), halosulfuron-methyl, haloxyfop-etotyl, haloxyfop-methyl, hexazinone, HOK-201 (7V-(2,4-difluorophenyl)-l,5-dihydro- N-( 1 -methylethyl)-5-oxo- 1 -[(tetrahydro-2H-pyran-2-yl)methyl]-4H- 1 ,2,4-triazole- 4-carboxamide), imazamethabenz-methyl, imazamox, imazapic, imazapyr, imazaquin, imazaquin-ammonium, imazethapyr, imazethapyr-ammonium, imazosulfuron, indanofan, iodosulfuron-methyl, ioxynil, ioxynil octanoate, ioxynil-sodium, isoproturon, isouron, isoxaben, isoxaflutole, isoxachlortole, isoxadifen, KUΗ-021 (7V-[2-[(4,6-dimethoxy- 2-pyrimidinyl)hydroxymethyl] -6-(methoxymethyl)phenyl] -1,1 -difluoromethane- sulfonamide), lactofen, lenacil, linuron, maleic hydrazide, MCPA and its salts (e.g., MCPA- dimethylammonium, MCPA-potassium and MCPA-sodium, esters (e.g., MCPA- 2-ethylhexyl, MCPA-butotyl) and thioesters (e.g., MCPA-thioethyl), MCPB and its salts (e.g., MCPB-sodium) and esters (e.g., MCPB-ethyl), mecoprop, mecoprop-P, mefenacet, mefluidide, mesosulfuron-methyl, mesotrione, metam-sodium, metamifop, metamitron, metazachlor, methabenzthiazuron, methylarsonic acid and its calcium, monoammonium, monosodium and disodium salts, methyldymron, metobenzuron, metobromuron, metolachlor, S-metholachlor, metosulam, metoxuron, metribuzin, metsulfuron-methyl, molinate, monolinuron, naproanilide, napropamide, naptalam, neburon, nicosulfuron, norflurazon, orbencarb, oryzalin, oxadiargyl, oxadiazon, oxasulfuron, oxaziclomefone, oxyfluorfen, paraquat dichloride, pebulate, pelargonic acid, pendimethalin, penoxsulam, pentanochlor, pentoxazone, perfluidone, pethoxyamid, phenmedipham, picloram, picloram-potassium, picolinafen, pinoxaden, piperofos, pretilachlor, primisulfuron-methyl, prodiamine, profoxydim, prometon, prometryn, propachlor, propanil, propaquizafop, propazine, propham, propisochlor, propoxycarbazone, propyzamide, prosulfocarb, prosulfuron, pyraclonil, pyraflufen-ethyl, pyrasulfotole, pyrazogyl, pyrazolynate, pyrazoxyfen, pyrazosulfuron-ethyl, pyribenzoxim, pyributicarb, pyridate, pyriftalid, pyriminobac-methyl, pyrimisulfan, pyrithiobac, pyrithiobac-sodium, quinclorac, quinmerac, quinoclamine, quizalofop-ethyl, quizalofop-P-ethyl, quizalofop-P-tefuryl, rimsulfuron, sethoxydim, siduron, simazine, simetryn, sulcotrione, sulfentrazone, sulfometuron-methyl, sulfosulfiiron, 2,3,6-TBA, TCA, TCA-sodium, tebutam, tebuthiuron, tepraloxydim, terbacil, terbumeton, terbuthylazine, terbutryn, thenylchlor, thiazopyr, thifensulfuron-methyl, thiobencarb, tiocarbazil, topramezone, tralkoxydim, tri-allate, triasulfuron, triaziflam, tribenuron-methyl, triclopyr, triclopyr-butotyl, triclopyr-triethylammonium, tridiphane, trietazine, trifloxysulfuron, trifluralin, triflusulfuron-methyl, tritosulfuron and vemolate. Other herbicides also include bioherbicides such as Alternaria destruens Simmons, Colletotrichum gloeosporiodes (Penz.) Penz. & Sacc, Drechsiera monoceras (MTB-951), Myrothecium verrucaria (Albertini & Schweinitz) Ditmar: Fries, Phytophthora palmivora (Butl.) Butl. and Puccinia thlaspeos Schub. Combinations of compounds of the invention with other herbicides can result in a greater-than-additive (i.e. synergistic) effect on weeds and/or a less-than-additive effect (i.e. safening) on crops or other desirable plants. In certain instances, combinations with other herbicides having a similar spectrum of control but a different mode of action will be particularly advantageous for preventing the development of resistant weeds. Herbicidally effective amounts of compounds of the invention as well as herbicidally effective amounts of other herbicides can be easily determined by one skilled in the art through simple experimentation.

Preferred for better control of undesired vegetation (e.g., lower use rate, broader spectrum of weeds controlled, or enhanced crop safety) or for preventing the development of resistant weeds are mixtures of the compounds of this invention with a herbicide selected from the group consisting of diuron, hexazinone, terbacil, bromacil, glyphosate (particularly glyphosate-isopropylammonium, glyphosate-sodium, glyphosate-potassium, glyphosate- trimesium), glufosinate (particularly glufosinate-ammonium), azimsulfuron, chlorsulfuron, ethametsulfuron-methyl, chlorimuron-ethyl, bensulfuron-methyl, rimsulfuron, sulfometuron-methyl, metsulfuron-methyl, nicosulfuron, tribenuron-methyl, thifensulfuron- methyl, flupyrsulfuron-methyl, flupyrsulfuron-methyl-sodium, paraquat dichloride, diquat dibromide, atrazine, metribuzin, acetochlor, metolachlor, S-metolachlor, alachlor, picloram, fosamine-ammonium, 2,4-D, 2,4-DB, dicamba, naptalam, aminopyralid, triclopyr, fluroxypyr, diflufenzopyr, mesotrione, sulcotrione, isoxaflutole, isoxaben, oryzalin, tebuthiuron, clopyralid, oxyfluorfen, and flumetsulam. Specifically preferred mixtures (compound numbers refers to compounds in Index Table A) are selected from the group: compound 1 and diuron; compound 2 and diuron; compound 1 and glyphosate; compound 2 and glyphosate; compound 1 and glufosinate; compound 2 and glufosinate; compound 1 and chlorsulfuron; compound 2 and chlorsulfuron; compound 1 and rimsulfuron; compound 2 and rimsulfuron; compound 1 and sulfometuron-methyl; compound 2 and sulfometuron- methyl; compound 1 and metsulfuron-methyl; compound 2 and metsulfuron-methyl; compound 1 and nicosulfuron; compound 2 and nicosulfuron; compound 1 and tribenuron- methyl; compound 2 and tribenuron-methyl; compound 1 and thifensulfuron-methyl; compound 2 and thifensulfuron-methyl; compound 1 and flupyrsulfuron-methyl (such as flupyrsulfuron-methyl-sodium); compound 2 and flupyrsulfuron-methyl (such as flupyrsulfuron-methyl-sodium); compound 1 and paraquat dichloride; compound 2 and paraquat dichloride; compound 1 and diquat dibromide; compound 2 and diquat dibromide; compound 1 and atrazine; compound 2 and atrazine; compound 1 and metribuzin; compound 2 and metribuzin; compound 1 and acetochlor; compound 2 and acetochlor; compound 1 and metolachlor (such as S-metolachlor); compound 2 and metolachlor (such as S-metolachlor); compound 1 and alachlor; compound 2 and alachlor; compound 1 and picloram; compound 2 and picloram; compound 1 and fosamine-ammonium; compound 2 and fosamine- ammonium; compound 1 and 2,4-D; compound 2 and 2,4-D; compound 1 and 2,4-DB; compound 2 and 2,4-D,B; compound 1 and dicamba; compound 2 and dicamba; compound 1 and naptalam; compound 2 and naptalam; compound 1 and aminopyralid; compound 2 and aminopyralid; compound 1 and triclopyr; compound 2 and triclopyr; compound 1 and fluroxypyr; compound 2 and fluroxypyr; compound 1 and diflufenzopyr; compound 2 and diflufenzopyr; compound 1 and mesotrione; compound 2 and mesotrione; compound 1 and sulcotrione; compound 2 and sulcotrione; compound 1 and isoxaflutole; compound 2 and isoxaflutole; compound 1 and isoxaben; compound 2 and isoxaben; compound 1 and oryzalin; compound 2 and oryzalin; compound 1 and tebuthiuron; compound 2 and tebuthiuron; compound 1 and clopyralid; compound 2 and clopyralid; compound 1 and oxyfluorfen; compound 2 and oxyfluorfen; compound 1 and flumetsulam; compound 2 and flumetsulam.

The proportions of the compounds of the invention with other herbicidal active ingredients in herbicidal compositions are generally in the ratio of 100:1 to 1: 100, more commonly 10:1 to 1:10 and most commonly 5:1 to 1:5 by weight. The optimum ratios can be easily determined by those skilled in the art based on the weed control spectrum desired.

Particularly noteworthy because of greater than additive (i.e. synergistic) efficacy on certain weeds are mixtures of compounds of the invention with auxin transport inhibitors (phytotropins), an example being the combination of compound 1 (methyl 4-amino- 3,5-dichloro-6-cyclopropyl-2-pyridinecarboxylate) with diflufenzopyr. Auxin transport inhibitors are chemical substances that inhibit auxin transport in plants, such as by binding with an auxin-carrier protein. Other examples of auxin transport inhibitors include naptalam (also known as JV-(I -naphthyl)phthalamic acid and 2-[(l-naphthalenylamino)carbonyl]- benzoic acid), Q-hydroxyfluorene-P-carboxylic acid and 2,3,5-triiodobenzoic acid. Therefore an aspect of the present invention relates to a herbicidal mixture comprising synergistically effective amounts of a compound of Formula I and an auxin transport inhibitor. Synergistically effective amounts of auxin transport inhibitors with the compounds of the invention can be easily determined. Compounds of this invention can also be used in combination with herbicide safeners such as benoxacor, BCS (l-bromo-4-[(chloromethyl)sulfonyl]benzene), cloquintocet-mexyl, cyometrinil, dichlormid, 2-(dichloromethyl)-2-methyl-l,3-dioxolane (MG 191), fenchlorazole-ethyl, fenclorim, flurazole, fluxofenim, furilazole, isoxadifen-ethyl, mefenpyr- ethyl, methoxyphenone ((4-methoxy-3-methylphenyl)(3-methylphenyl)methanone), naphthalic anhydride (1,8-naphthalic anhydride) and oxabetrinil to increase safety to certain crops. Antidotally effective amounts of the herbicide safeners can be applied at the same time as the compounds of this invention, or applied as seed treatments. Therefore an aspect of the present invention relates to a herbicidal mixture comprising a compound of this invention and an antidotally effective amount of a herbicide safener. Seed treatment is particularly useful for selective weed control, because it physically restricts antidoting to the crop plants. Therefore a particularly useful embodiment of the present invention is a method for selectively controlling the growth of undesired vegetation in a crop comprising contacting the locus of the crop with a herbicidally effective amount of a compound of this invention wherein seed from which the crop is grown is treated with an antidotally effective amount of safener. Antidotally effective amounts of safeners can be easily determined by one skilled in the art through simple experimentation.

Compounds of this invention can also be used in combination with plant growth regulators such as aviglycine, 7V-(phenylmethyl)-lH-purin-6-amine, epocholeone, gibberellic acid, gibberellin A4 and A₇, harpin protein, mepiquat chloride, prohexadione calcium, prohydrojasmon, sodium nitrophenolate and trinexapac-methyl, and plant growth modifying organisms such as Bacillus cereus strain BPOl.

The following Tests demonstrate the control efficacy of a compound of this invention against specific weeds. The weed control afforded by the compounds of the invention is not limited, however, to these species. See Index Table A for compound descriptions. The abbreviation "Ex." stands for "Example" and is followed by a number indicating in which example the compound is prepared. INDEX TABLE A

In the column "(R⁶)_p" a dash ("-") indicates unsubstituted. Compound RL R² _. R3 El R£ (E-^E m.p.(°α

1 (Ex. 1) Cl H H Cl CO₂CH₃ 125-126

2 (Ex. 2) H H H Cl CO₂CH₃ 100-103

BIOLOGICAL EXAMPLES OF THE INVENTION TEST A

Seeds selected from barnyardgrass {Echinochloa crus-gallϊ), cocklebur (Xanthium strumarium), corn (Zea mays), large crabgrass (Digitaria sanguinalis), giant foxtail (Setaria faberii), lambsquarters {Chenopodium album), morningglory (Ipomoea coccinea), pigweed (Amaranthus retroβexus), Surinam grass {Brachiaria decumbens), velvetleaf (Abutilon theophrasti), and wheat (Triticum aestivum) were planted and treated preemergence with compound number 1 formulated in a non-phytotoxic solvent mixture which included a surfactant.

At the same time, plants selected from these crop and weed species and also blackgrass {Alopecurus myosuroides) and wild oat (Avena fatua) were treated with postemergence applications of compound number 1 formulated in the same manner. Plants ranged in height from 2 to 18 cm (1- to 4-leaf stage) for postemergence treatments. Plant species in the flooded paddy test consisted of rice (Orγza sativa), umbrella sedge (Cyperus difformis), duck salad (Heteranthera limosά) and barnyardgrass {Echinochloa crus-galli) grown to the 2-leaf stage for testing. Treated plants and controls were maintained in a greenhouse for 13 to 15 days, after which time all species were compared to controls and visually evaluated. Plant response ratings, summarized in Table A, are based on a scale of 0 to 100 where 0 is no effect and 100 is complete control. A dash (-) response means no test result.

Table A Compound

1000 g ai/ha 1

Flood

Barnyardgrass 80

Ducksalad 90

Rice 80

Sedge, Umbrella 90 Table A Compound Table A Compound

500 g ai/ha 1 125 g ai/ha 1

Postemergence Postemergence

Barnyardgrass 90 Barnyardgrass 10

Blackgrass 60 Blackgrass 60

Cocklebur 90 Cocklebur 60

Corn 30 Corn 0

Crabgrass, Large 70 Crabgrass, Large 20

Foxtail, Giant 30 Foxtail, Giant 0

Lambsquarters 100 Lambsquarters 80

Morningglory 30 Morningglory 20

Oat, Wild 60 Oat, Wild 60

Pigweed 100 Pigweed 60

Surinam Grass 70 Surinam Grass 40

Velvetleaf 100 Velvetleaf 60

Wheat 60 Wheat 60

Table A Compound Table A Compound

500 g ai/ha 1 125 g ai/ha 1

Preemergence Preemergence

Barnyardgrass 90 Barnyardgrass 50

Cocklebur 100 Cocklebur 70

Corn 0 Corn 0

Crabgrass, Large 80 Crabgrass, Large 50

Foxtail, Giant 70 Foxtail, Giant 30

Lambsquarters 100 Lambsquarters 100

Morningglory 0 Morningglory 0

Pigweed 100 Pigweed 80

Surinam Grass 80 Surinam Grass 40

Velvetleaf 70 Velvetleaf 40

Wheat 30 Wheat 0

TESTB

Plant species in the flooded paddy test consisted of rice (Oryza sativa), umbrella sedge (Cyperus difformis), duck salad (Heteranthera limosa) and barnyardgrass (Echinochloa crus- galli) grown to the 2-leaf stage for testing and were treated with compound number 1 formulated in a non-phytotoxic solvent mixture which included a surfactant. Treated plants and controls were maintained in a greenhouse for 12 to 14 days, after which time all species were compared to controls and visually evaluated. Plant response ratings, summarized in TableB,arebasedonascaleofOto 100where0isnoeffectand 100iscompletecontrol. A dash(-)responsemeansnotestresult.

Table B Compound Table B Compound

500 g ai/ha 1 250 g ai/ha 1

Flood Flood

Barnyardgrass 60 Barnyardgrass 45

Ducksalad 75 Ducksalad 75

Rice 20 Rice 10

Sedge, Umbrella 65 Sedge, Umbrella 60

Table B Compound Table B Compound

125 g ai/ha 1 62 g ai/ha 1

Flood Flood

Barnyardgrass 20 Barnyardgrass 0

Ducksalad 30 Ducksalad 0

Rice 0 Rice 0

Sedge, Umbrella 0 Sedge, Umbrella 0

Claims

CLAIMS What is claimed is:

1. A compound selected from Formula I, an TV-oxide or an agriculturally suitable salt thereof,

wherein

R¹ is H, F or Cl;

R² is H, C₁-C₄ alkyl optionally substituted with 1-2 R⁷, C₂-C₄ alkenyl optionally substituted with 1-2 R⁸, or C2-C4 alkynyl optionally substituted with 1-2 R⁹; or R² is C(=O)Rl0, nitro, ORH, S(O)₂R¹², N(R¹³)R¹⁴ or N=C(R¹⁵)Rl6_;

R³ is H, C₁-C₄ alkyl optionally substituted with 1-2 R¹⁷ or C(=O)R¹⁰; or R² and R³ are taken together as a radical selected from -(CH₂)₄-, -(CH₂)S-,

-CH₂CH=CHCH₂- and -(CH₂)₂O(CH₂)₂-, each radical optionally substituted with 1-2 R¹⁸; or R² and R³ are taken together as =C(R! 9)N(R²⁰)R²1 or =C(R²²)OR²³ ;

R⁴ is halogen;

R⁵ is CO₂H or a herbicidally effective derivative of CO₂H; each R⁶ is independently halogen, C₁-C₆ alkyl, C₁-C₆ haloalkyl, C₂-C₆ alkenyl, C₂-

C₆ haloalkenyl, C₁-C₃ alkoxy, C₁-C₂ haloalkoxy, C₁-C₃ alkylthio or C₁-C₂ haloalkylthio; each R⁷, R⁸ and R⁹ is independently halogen, C₁-C₃ alkoxy, C₁-C₃ haloalkoxy, C₁-C₃ alkylthio, C₁-C₃ haloalkylthio, amino, C₁-C₃ alkylamino, C₂-C₄ dialkylamino or C2-C4 alkoxycarbonyl; each R¹⁰ is independently H, C₁-C₁₄ alkyl, C₁-C₃ haloalkyl, C₁-C₄ alkoxy, phenyl, phenoxy or benzyloxy;

R¹¹ is H, C₁-C₄ alkyl, C₁-C₃ haloalkyl or CHR²⁴C(O)OR²S; R¹² is C₁-C₄ alkyl or C₁-C₃ haloalkyl; R¹³ is H, C₁-C₄ alkyl or C(=O)R²<>; R¹⁴ is H or C₁-C₄ alkyl; R¹⁵ is H, C₁-C₄ alkyl or phenyl optionally substituted with 1-3 R²⁷;

R¹⁶ is H or C₁-C₄ alkyl; or R¹⁵ and R¹⁶ are taken together as -(CH₂)₄- or -(CH₂)₅-; each R¹⁷ is independently halogen, C1-C3 alkoxy, C1-C3 haloalkoxy,

C₁-C 3 alkylthio, C1-C3 haloalkylthio, amino, C^-C₃ alkylamino, C2-C4 dialkylamino or C2-C4 alkoxycarbonyl; each R¹⁸ is independently halogen, C₁-C₃ alkyl, C₁-C₃ alkoxy, C₁-C₃ haloalkoxy, C₁-C₃ alkylthio, C1-C3 haloalkylthio, amino, C₁-C₃ alkylamino, C2-C4 dialkylamino or C2-C4 alkoxycarbonyl; R¹⁹ is H or C₁-C₄ alkyl;

R²⁰ and R²¹ are independently H or C_j-C₄ alkyl; or

R²⁰ and R²¹ are taken together as -(CH₂)₄-, -(CH₂)₅-, -CH₂CH=CHCH₂- or -(CH₂)₂O(CH₂)₂-;

R²² is H or C₁-C₄ alkyl; R²³ is C₁-C₄ alkyl;

R²⁴ is H, C₁-C₄ alkyl or C₁-C₄ alkoxy; R²⁵ is H, C₁-C₄ alkyl or benzyl. R²⁶ is H, C₁-C₁₄ alkyl, C₁-C₃ haloalkyl, C₁-C₄ alkoxy, phenyl, phenoxy or benzyloxy; each R²⁷ is independently CH3, Cl or OCH3; and p is an integer from 0 to 5.

2. The compound of Claim 1 wherein R⁵ is CO₂R²⁹, CH₂OR³⁰, CH(OR³¹)(OR³²), CHO, C(=NOR³³)H, C(=NNR³⁴R³⁵)H,

C(=O)N(R³⁶)R³⁷, C(=S)OR³⁸, C(=O)SR³⁹, C(=S)SR⁴⁰ or C(=NR⁴¹)YR⁴²; R²⁹ is H, -CH£C(O)O(CH₂)_m}, -N=C(R⁴³)R⁴⁴; or a radical selected from C₁-C₁₄ alkyl, 03-C₁₂ cycloalkyl, C₄-C₁₂ alkylcycloalkyl, C₄-C₁₂ cycloalkylalkyl, C₂-C₁₄ alkenyl, C₂-C₁₄ alkynyl and phenyl, each radical optionally substituted with 1-3 R⁴⁵; or

R²⁹ is a divalent radical linking the carboxylic ester function CO₂R²⁹ of each of two pyrimidine ring systems of Formula I, the divalent radical selected from -CH₂-, -(CH₂)₂-, -(CH₂)₃- and -CH(CH₃)CH₂-;

R³⁰ is H, C₁-C₁₀ alkyl optionally substituted with 1-3 R⁴⁶, or benzyl; R³¹ and R³² are independently C₁-C₄ alkyl or C₁-C₃ haloalkyl; or

R³¹ and R³² are taken together as -CH₂CH₂-, -CH₂CH(CH₃)- or -(CH₂)₃-;

R³³ is H, C₁-C₄ alkyl, C₁-C₄ haloalkyl or benzyl;

R³⁴ is H, C₁-C₄ alkyl, C₁-C₄ haloalkyl, C₂-C₄ alkylcarbonyl, C₂-C₄ alkoxycarbonyl or benzyl; R³⁵ is H, C₁-C₄ alkyl or C₁-C₄ haloalkyl;

R³⁶ is H, C₁-C₄ alkyl, hydroxy, C₁-C₄ alkoxy or S(O)₂R⁴⁷; R³⁷ is H or C₁-C₄ alkyl; R³⁸, R³⁹ and R⁴⁰ are H; or a radical selected from C₁-C₁₄ alkyl, C₃-C₁₂ cycloalkyl,

C₄-C₁₂ alkylcycloalkyl, C₄-C₁₂ cycloalkylalkyl, C₂-C₁₄ alkenyl and C₂-C₁₄ alkynyl, each radical optionally substituted with 1-3 R⁴⁵; Y is O, S or NR⁴⁸; R⁴¹ is H, C₁-C₃ alkyl, C₁-C₃ haloalkyl, C₂-C₄ alkoxyalkyl, OH or C₁-C₃ alkoxy;

R⁴² is C₁-C₃ alkyl, C₁-C₃ haloalkyl or C₂-C₄ alkoxyalkyl; or R⁴¹ and R⁴² are taken together as -(CH₂)₂-, -CH₂CH(CH₃)- or -(CH₂)₃-; R⁴³ and R⁴⁴ are independently C₁-C₄ alkyl; each R⁴⁵ is independently halogen, cyano, hydroxycarbonyl, C₂-C₄ alkoxycarbonyl, hydroxy, C₁-C₄ alkoxy, C₁-C₄ haloalkoxy, C₁-C₄ alkylthio, C₁-C₄ haloalkylthio, amino, C₁-C₄ alkylamino, C₂-C₄ dialkylamino, -CH£O(CH₂)_n} or phenyl optionally substituted with 1-3 R⁴⁹; or two R⁴⁵ are taken together as -OC(O)O- or

or two R⁴⁵ are taken together as an oxygen atom to form, with the carbon atom to which they are attached, a carbonyl moiety; each R⁴⁶ is independently halogen, C₁-C₄ alkoxy, C₁-C₄ haloalkoxy, C₁-C₄ alkylthio, C₁-C₄ haloalkylthio, amino, C₁-C₄ alkylamino or C₂-C₄ dialkylamino; or two R⁴⁶ are taken together as an oxygen atom to form, with the carbon atom to which they are attached, a carbonyl moiety;

R⁴⁷ is C₁-C₄ alkyl, C₁-C₃ haloalkyl Or NR⁵¹R⁵²;

R⁴⁸ is H, C₁-C₃ alkyl, C₁-C₃ haloalkyl or C₂-C₄ alkoxyalkyl; each R⁴⁹ is independently halogen, C₁-C₄ alkyl, C₁-C₃ haloalkyl, hydroxy, C₁-C₄ alkoxy, C₁-C₃ haloalkoxy, C₁-C₃ alkylthio, C₁-C₃ haloalkylthio, amino, C₁-C₃ alkylamino, C₂-C₄ dialkylamino or nitro; each R⁵⁰ is independently selected from H and C₁-C₄ alkyl; R⁵^ and R⁵² are independently H or C₁-C₄ alkyl; m is an integer from 2 to 3; and n is an integer from 1 to 4.

3. The compound of Claim 2 wherein p is 0.

4. The compound of Claim 3 wherein R⁵ is CO₂R²⁹, CH₂OR³⁰ or CHO.

5. The compound of Claim 4 wherein R² is H, CH₃ or C(O)R¹⁰;

R³ is H or CH₃; or R² and R³ are taken together as =C(R¹⁹)N(R²⁰)R²¹; and

R¹⁰, R¹⁹, R²⁰ and R²¹ are each independently H or CH₃.

6. The compound of Claim 5 wherein R⁵ is CO₂R²⁹; and R² and R³ are H.

7. The compound of Claim 6 wherein R²⁹ is H, C₁-C₄ alkyl or benzyl.

8. The compound of Claim 1 which is selected from the group consisting of methyl 4-amino-3,5-dichloro-6-cyclopropyl-2-pyridinecarboxylate, 4-amino-3,5-dichloro-6-cyclopropyl-2-pyridinecarboxylic acid, methyl 4-amino-3-chloro-6-cyclopropyl-2-pyridinecarboxylate,

4-amino-3-chloro-6-cyclopropyl-2-pyridinecarboxylic acid, methyl 4-amino-3-chloro-6-cyclopropyl-5-fluoro-2-pyridinecarboxylate, and 4-amino- 3 -chloro-ό-cyclopropyl-S -fluoro-2 -pyridinecarboxylic acid.

9. A method for controlling the growth of undesired vegetation comprising contacting the vegetation or its environment with a herbicidally effective amount of a compound of Claim 1.

10. A herbicidal composition comprising a herbicidally effective amount of a compound of Claim 1, an effective amount of at least one additional active ingredient selected from the group consisting of an other herbicide and a herbicide safener, and at least one of a surfactant, a solid diluent or a liquid diluent.