WO1995021846A1

WO1995021846A1 - Arthropodicidal tetrahydropyrimidines

Info

Publication number: WO1995021846A1
Application number: PCT/US1995/001616
Authority: WO
Inventors: Stephen Frederick Mccann
Original assignee: E.I. Du Pont De Nemours And Company
Priority date: 1994-02-09
Filing date: 1995-02-09
Publication date: 1995-08-17
Also published as: PL315813A1; AU679350B2; IL112577A0; CN1140452A; EP0743947A1; AU1913495A; MX9603273A; HU9602186D0; BR9506960A; JPH09507676A; HUT76814A

Abstract

Arthropodicidal compounds, compositions and use of compounds having formula (I), wherein X, A, R?1, R2, R3, R4, R5 and R6¿ are as defined in the text.

Description

TITLE

ARTHROPODICIDAL TETRAHYDROPYRIMIDINES

The present invention pertains to tetrahydropyrimidines which are useful as arthropodicides. U.S. 4,831,036 discloses insecticidal tetrahydropyrimidines that do not suggest those of the instant invention.

SUMMARY OF THE INVENTION

This invention pertains to compounds of Formula I , including all geometric and stereoisomers, agriculturally suitable salts thereof, agricultural compositions containing them and their use to control arthropods in both agronomic and nonagronomic environments. The compounds are:

wherein

X is selected from the group Si and Ge;

A is selected from the group C₁-C₂₀ alkylene, C₂-C₂₀ alkenylene, C₂-C₂₀

alkynylene, C₃-C₈ cycloalkylene, C₇-C₁₀ aralkylene and phenylene, each group optionally substituted with 1-3 substituents independently selected from W; or A is a direct bond;

R¹ and R³ are independently selected from the group H, C₁-C₁₀ alkyl, C₂-C₁₀ alkenyl or C₂-C₁₀ alkynyl, each group optionally substituted with 1-2 substituents independently selected from the group halogen, CN, C(O)R⁷, C(S)R⁷, NO₂, OH, SC(O)R⁷, SC(S)R⁷, OC(O)R⁷, OC(S)R⁷, NR⁸C(O)R⁷, NR⁸C(S)R⁷, SH, Si(R⁸)(R⁹)(R¹⁰), C₁-C₄ alkoxy, C₁-C₄ haloalkoxy, C₁-C₄ alkylthio, C₁-C₄ alkylamino, C₂-C₈ dialkylamino, C₃-C₈ cycloalkyl and phenyl optionally substituted with 1-3 substituents independently selected from W¹; C₃-C₈ cycloalkyl optionally substituted with 1-3 substituents independently selected from the group halogen, C₁-C₂ alkyl and C₁-C₂ haloalkyl; C(O)R¹¹; C(S)R¹¹; phenyl optionally substituted with 1-3 substituents independently selected from W¹; C₁-C₃ alkyl substituted with a 5- or 6-membered aromatic ring, attached through carbon or nitrogen, containing 1 to 4 heteroatoms independently selected from the group 0-4 nitrogen, 0-1 oxygen, and 0-1 sulfur, the ring optionally substituted with 1-3 substituents independently selected from W¹; and a 5- or 6-membered aromatic ring, attached through carbon or nitrogen, containing 1 to 4 heteroatoms independently selected from the group 0-4 nitrogen, 0- 1 oxygen, and 0-1 sulfur, the ring optionally substituted with 1-3 substituents independently selected from W¹;

R² is selected from the group H, C₁-C₆ alkyl, C₁-C₆ haloalkyl, C₂-C₆ alkenyl,

C₂-C₆ haloalkenyl, C₂-C₆ alkynyl, C₂-C₆ haloalkynyl, C₃-C₇ cycloalkyl, C₃-C₇ halocycloalkyl and C₄-C₇ cycloalkylalkyl, each group optionally substituted with 1-3 substituents independently selected from W; or

R² and R³ can be taken together as CH₂CH₂ and CH₂CH₂CH₂ each group

optionally substituted with 1-2 CH₃;

R⁴ is selected from the group H and C₃-C₆ trialkylsilyl; or R⁴ is selected from the group C₁-C₁₀ alkyl, C₂-C₁₀ alkenyl, C₂-C₁₀ alkynyl, C₁-C₁₀ alkoxy, C₁-C₁₀ alkylthio, phenyl, phenoxy, phenylthio and naphthyl, each group optionally substituted with 1-3 substituents independently selected from W¹;

R⁵ and R⁶ are independently selected from the group C₁-C₁₀ alkyl, C₂-C₁₀

alkenyl, C₂-C₁₀ alkynyl, C₁-C₁₀ alkoxy, C₁-C₁₀ alkylthio, phenyl, phenoxy, phenylthio and naphthyl, each group optionally substituted with 1-3 substituents independently selected from W¹; OH; and C₃-C₆ trialkylsilyl;

R⁷ is selected from the group H, NH₂, OH, C₁-C₆ alkyl, C₁-C₆ haloalkyl, C₁-C₆ alkoxy, C₁-C₆ haloalkoxy, C₁-C₆ alkylthio, C₁-C₄ alkylamino, C₂-C₈ dialkylamino and phenyl optionally substituted with 1-3 substituents independently selected from W¹;

R⁸ is H; or R⁸ is selected from the group C₁-C₁₀ alkyl, C₂-C₁₀ alkenyl, C₂-C₁₀ alkynyl, C₁-C₁₀ alkoxy, phenoxy, phenyl and naphthyl, each group optionally substituted with 1-3 substituents independently selected from W¹ ;

R⁹ and R¹⁰ are independently selected from the group C₁-C₁₀ alkyl, C₂-C₁₀

alkenyl, C₂-C₁₀ alkynyl, C₁-C₁₀ alkoxy, phenoxy, phenyl and naphthyl, each group optionally substituted with 1-3 substituents independently selected from W¹; and OH;

R¹¹ is selected from the group H, NH₂, OH, C₁-C₆ alkyl, C₁-C₆ haloalkyl, C₁-C₆ alkoxy, C₁-C₆ haloalkoxy, C₁-C₂ alkylthio, C₁-C₄ alkylamino, C₂-C₈ dialkylamino and phenyl optionally substituted with 1-3 substituents independently selected from W¹;

W is selected from the group halogen, CN, NO₂, OH, C₁-C₆ alkyl, C₁-C₆

haloalkyl, C₁-C₆ alkoxy and C₁-C₆ haloalkoxy; and

W¹ is selected from the group halogen, CN, NO₂, C₁-C₂ alkyl, C₁-C₂ haloalkyl, C₁-C₂ alkoxy, C₁-C₂ haloalkoxy, C₁-C₂ alkylthio, C₁-C₂ haloalkylthio, C₁-C₂ alkylsulfonyl, C₁-C₂ haloalkylsulfonyl, C₁-C₄ alkylamino, C₂-C₈ dialkylamino and C₃-C₆ trialkylsilyl;. Preferred Compounds A are compounds of Formula I wherein

A is C₁-C₆ alkylene;

R¹ is C₁-C₃ alkyl substituted with a 5- or 6-membered aromatic ring, attached through carbon or nitrogen, containing 1 to 4 heteroatoms independently selected from the group 0-4 nitrogen, 0-1 oxygen, and 0-1 sulfur, the ring optionally substituted with 1-3 substituents independently selected from W¹;

R⁴ is selected from the group C₁-C₁₀ alkyl and phenyl, each group

optionally substituted with 1-3 substituents independently selected from W¹;

R⁵ and R⁶ are independently selected from the group C₁-C₁₀ alkyl and phenyl, each group optionally substituted with 1-3 substituents independently selected from W⁵ ; and

W¹ is selected from the group halogen and C₁-C₂ haloalkyl. Preferred Compounds B are compounds of Preferred A wherein

X is Si;

R¹ is CH₂ substituted with pyridyl, thiazole or isoxazole, the ring

optionally substituted with 1-2 halogen or 1-2 methyl;

R² and R³ are taken together as CH₂CH₂ or CH₂CH₂CH₂ each group optionally substituted with 1-2 CH3; and

R⁴, R⁵ and R⁶ are independently selected from C₁-C₃ alkyl, C₁-C₃ alkoxy and phenyl.

Preferred Compounds C are compounds of Preferred A wherein

X is Si;

R¹ is CH₂ substituted with pyridyl, thiazole or isoxazole, the ring

optionally substituted with 1-2 halogen;

R² is selected from the group H and C₁-C₃ alkyl; and

R⁴, R⁵ and R⁶ are independently selected from C₁-C₃ alkyl, C_1-C₃ alkoxy and phenyl.

Specifically preferred for biological activity is Compound D of Preferred B which is:

1 -[(6-chloro-3-pyridinyl)methyl]-1,2,3,5,6,7-hexahydro-2-methyl-8-nitro- 6-[(trimethylsilyl)methyl]imidazo[1,2-c]pyrimidine.

Specifically preferred for biological activity is Compound E of Preferred B which is:

1 -[(6-chloro-3-pyridinyl)methyl]-1,2,3,5,6,7-hexahydro-8-nitro- 6-[(trimethylsilyl)methyl]imidazo[1,2-c]pyrimidine.

Compounds of this invention can exist as one or more stereoisomers. The various stereoisomers include enantiomers, diastereomers 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 said stereoisomers. Accordingly, the present invention comprises racemic mixtures, individual stereoisomers, and optically active mixtures of compounds of Formula I as well as agriculturally suitable salts thereof.

The term "5- or 6-membered aromatic ring" is defined as those rings which satisfy the Hückel rule; examples include 5- or 6-membered monocyclic aromatic rings containing 0 to 4 heteroatoms such as phenyl, furyl, furazanyl, thienyl, pyrrolyl, pyrazolyl, oxazolyl, oxadiazolyl, imidazolyl, isoxazolyl, thiazolyl, thiadiazolyl isothiazolyl, tetrazolyl, pyridyl, pyrimidinyl, pyridazinyl, pyrazinyl and triazinyl with said ring attached through any available carbon or nitrogen. For example, when the aromatic ring is furyl, it can be 2-furyl or 3-furyl, for pyrrolyl, the aromatic ring is 1-pyrrolyl, 2-pyrrolyl or 3-pyrrolyl, for pyridyl, the aromatic ring is 2-pyridyl, 3-pyridyl or 4-pyridyl and similarly for other monocyclic aromatic rings.

In the above recitations, the term "alkyl", used either alone or in compound words such as "alkylthio" or "haloalkyl" denotes straight-chain or branched alkyl, such as, methyl, ethyl, n-propyl, i-propyl, or the different isomers through C₁₀. Examples of "alkylene" include CH₂, CH₂CH₂, CH₂CH₂CH₂ and the different isomers through C₂₀. "Alkenyl" denotes straight-chain or branched alkenes such as ethenyl, 1-propenyl, 2-propenyl, and the different isomers through C₁₀. "Alkenyl" also denotes polyenes such as 1,3-hexadiene. Examples of "alkenylene" include CH=CH, CH₂CH=CH,

CH=CHCH₂ and the different isomers through C₂₀. "Alkynyl" denotes straight-chain or branched alkynes such as ethynyl, 1-propynyl, 3-propynyl and the different isomers through C₁₀. Examples of "alkynylene" include C≡C, CH₂C≡C, C=CCH₂ and the different isomers through C₂₀. "Alkoxy" denotes, for example, methoxy, ethoxy, n-propyloxy, isopropyloxy and the different isomers through C₁₀. "Alkylthio" denotes straight-chain or branched alkylthio moieties such as methylthio, ethylthio, and the different propylthio, butylthio, pentylthio and hexylthio isomers. "Alkylsulfonyl" denotes CH₃S(O)₂ and CH₃CH₂S(O)₂. "Alkylamino" denotes methylamino, ethylamino, n-propylamino, isopropylamino and the different butylamino isomers. "Dialkylamino" denotes nitrogen substituted with two alkyl groups, which may be different. Examples include N,N-dimethylamino and N-ethyl-N-methylamino. "Cycloalkyl" denotes, for example, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl and cyclooctyl. Examples of "cycloalkylalkyl" include cyclopropylmethyl, cyclopropylethyl, cyclobutylmethyl and the different C₆ and C₇ isomers bonded to straight-chain or branched alkyl groups. The term "halogen", either alone or in compound words such as "haloalkyl", denotes 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. Examples of "haloalkenyl" include (Cl)₂C=CHCH₂ and CF₃CH₂CH=CHCH₂. Examples of "haloalkynyl" include HC≡CCHCl, CF₃C≡C, CCl₃C≡C and FCH₂C=CCH₂. Examples of "haloalkoxy" include CF₃O, CCl₃CH₂O, CF₂HCH₂CH₂O and CF₃CH₂O. Examples of "haloalkylthio" include CCl₃S, CF₃S, and CCl₃CH₂S. Examples of "haloalkylsulfonyl" include CF₃SO₂, CCl₃SO₂, CF₃CH₂SO₂ and CF₃CF₂SO₂. The total number of carbon atoms in a substituent group is indicated by the "C_i-C_j" prefix where i and j are numbers from 1 to 20. For example, C₁-C₂₀ alkylene designates methylene, ethylene, and propylene through dodecylene isomers; C₂ alkoxy designates CH₃CH₂O-; and C₃ alkoxy designates CH₃CH₂CH₂O- or

(CH₃)₂CHO-.

DETAILS OF THE INVENTION

The compounds of Formula I can be prepared by the reaction of Formula II compounds with one or more equivalents of an amine of Formula III and at least two molar equivalents of formaldehyde in a suitable solvent as depicted in Scheme 1. These reactions are typically carried out at temperatures ranging from 0 °C to the reflux temperature of the solvent, with 0 °C-25 °C being preferred. Scheme 1 reactions are typically complete within one day, however, certain Scheme 1 reactions may require longer reaction times (up to 5 days). Suitable solvents include alcohols such as methanol and ethanol, water, and polar aprotic solvents such as tetrahydrofuran and dimethylformamide. Formaldehyde can be used in amounts of about 2-10 molar equivalents. Either solid paraformaldehyde or aqueous solutions of formaldehyde can be used. In some cases, it is desirable to use a small amount of a strong, non-oxidizing acid, such as hydrochloric acid, as a catalyst. Alternatively, a hydrohalide or a hydrosulfonic acid salt of amine in can be used.

H

Compounds of Formula II can be prepared by reaction of compounds of

Formula IV with an amine of Formula V as shown in Scheme 2. Typically, compounds of Formula IV are combined with 1-20 molar equivalents of an amine of Formula V in a suitable solvent at temperatures ranging from 0-100 °C. Scheme 2 reactions typically require 6 to 48 h for completion, however longer reaction times may sometimes be required. Suitable solvents include but are not limited to, alcohols such as methanol, ethanol and isopropanol; water; acetonitrile; dimethyl formamide and dimethyl acetamide. Amines of Formula V can also be used as hydrochloride salts; in these cases an equivalent amount of a base (such as sodium hydroxide) is added to the reaction mixtures.

Alternatively, compounds of Formula II can be prepared by the reaction of Formula VI compounds with amines of Formula VII as depicted in Scheme 3 using conditions that are completely analogous to those described in Scheme 2.

Compounds of Formula IV can be prepared employing processes known in the art that involve reaction of nitroethene compounds of Formula VIII with amines of

Formula VII (Scheme 4). Compounds of Formula VI can be prepared by procedures which are analogous to those for compounds of Formula IV. Typical reaction conditions involve the combination of equimolar amounts of compounds of Formulas VII and VIII in a suitable solvent or solvent mixture at temperatures in the range of about 0-100 °C. Scheme 4 reactions typically require 6 to 48 h for completion. Suitable solvents typically have sufficient polarity to effect solution of compounds of Formulas VII and VIII, and include alcohols such as methanol, ethanol and isopropanol; ethers such as diethyl ether, tetrahydrofuran and dioxane; esters such as ethyl acetate; polar aprotic solvents such as dimethylformamide and dimethylacetamide; and water, as well as mixtures of solvents.

Alternatively, compounds of Formula I can be prepared by the reaction of tetrahydropyrimidines of Formula IX with amines of Formula VII as depicted in

Scheme 5 under conditions analogous to those described in Scheme 2. Preparation of compounds of Formula I by the reactions depicted in Scheme 5 are advantageous when either R¹ and/or R² are equal to H.

Compounds of Formula IX can be prepared by the reaction of Formula III amines with compounds of Formula VI in the presence of formaldehyde as shown in Scheme 6 using procedures analogous to those described in Scheme 1.

Alternatively, as shown in Scheme 7, compounds of Formula I (where R¹ is other than H) can be prepared by the reaction of compounds of Formula I (where R¹ is H) with an alkylating agent of Formula X in the presence of a proton acceptor in a suitable solvent. Typical proton acceptors include NaH, KH, K₂CO₃, NaHCO₃, and Cs₂CO₃, and suitable solvents include DMF, THF, acetonitrile and water. In some cases, Scheme 7 reactions are carried out under phase transfer conditions using solvents that include toluene, dichloromethane, dichloroethane, ether, hexanes, benzene and the like and an aqueous base, including NaOH, KOH, NaHCO₃, Na₂CO₃, K₂CO₃, among others.

Typical phase transfer catalysts include tetrasubstituted ammonium halide salts, such as tetrabutylammonium iodide, benzyl triethyl ammonium bromide and the like. Reactions are typically carried out at temperatures ranging from 20-150 °C and are completed in 1 h to 3 days; however, 6 to 24 h is usually preferred.

Alternatively, compounds of Formula I (where R³ is other than H) can be prepared as shown in Scheme 8 using procedures that are completely analogous to those described for Scheme 7 reactions.

The formation of compounds of Formula II (where R² and R³ are taken together to form a 5-or 6-membered ring and R¹ is other than H) is depicted in Scheme 9.

Conditions for carrying out Scheme 9 reactions are analogous to those described for

Alternatively, compounds of Formula II (where R² and R³ are taken together to form a 5- or 6-membered ring) can be prepared as shown in Scheme 10. Typical reactions involve the combination of equimolar amounts of Formula XII and VIII compounds in a suitable solvent or solvent mixture at temperatures in the range of about 0-100 °C for a time ranging from 2 to 48 h. Suitable solvents typically have sufficient polarity to effect solution of Formula XII and VIII compounds and include alcohols such as methanol, ethanol and isopropanol; ethers such as diethyl ether, tetrahydrofuran and dioxane; esters such as ethyl acetate; polar aprotic solvents such as dimethylformamide and dimethylacetamide; and water, as well as mixtures of solvents.

Diamines of Formula XII can be formed by reaction of Formula X compounds wth a stoichiometric excess of amines of Formula XIII as depicted in Scheme 11. Typical reactions involve the use of 1.5-10 equivalents of Formula XIII compounds in solvents such as methanol, ethanol, isopropanol, THF, water or acetonitrile, among others.

Scheme 11 reactions are sometimes carried out in the absence of solvent. Typical

reaction times for Scheme 11 reactions range from 30 min to several days, with 6 to 24 h being generally preferred.

Alternatively, Formula XII diamines where B is an optionally substituted CH₂CH₂ group can be prepared by the two-step procedure depicted in Scheme 12. In Step i of Scheme 12, amines of Formula XIV are treated with potassium cyanide and compounds of Formula XV in the presence of zero to three equivalents of acid to form aminonitriles of Formula XVI. One skilled in the art will recognize that compounds of Formula XV can be formaldehyde, acetaldehyde or acetone. Other cyanide salts as well as HCN can be used in the procedure as well as hydrohalide and other acid salts of Formula XIV. Suitable solvents include methanol, ethanol, isopropanol and water, as well as combinations of solvents. Scheme 12 reactions are usually complete with 24 h.

Alternative procedures for the preparation of amino nitriles such as XVI can be found in the literature (see, e.g., Synth. Commun., (1985), 15, 157; Synthesis, (1979), 127).

In Step ii of Scheme 12, aminonitriles of Formula XVI are reduced to form diamines of Formula XII. This reduction can usually be achieved using lithium aluminum hydride or borane in amounts ranging from 0.75 to 3 molar equivalents, in a solvent such as diethyl ether or THF. Reactions are carried out at temperatures ranging from -20 °C to the reflux temperature of the solvent for times ranging from 0.5 h to 2 days.

Alternatively, the reduction of compounds of Formula XVI to compounds of

Formula XII can be achieved using catalytic hydrogenation over a catalyst such as palladium on carbon or Raney nickel. The addition of ammonia to the hydrogenation reaction is sometimes useful to maximize the yield of diamines of Formula XII.

An alternative procedure for the preparation of diamines of Formula XII where B is an optionally substituted CH₂CH₂ group is depicted in Scheme 13. In Step i of

Scheme 13, amino amides of Formula XVII are treated with 1 to 2 molar equivalents of acid chlorides of Formula XVIII in the presence of 1 to 3 molar equivalents of a base such as NaOH, KOH, K₂CO₃, NaHCO₃, pyridine or triethylamine. Suitable solvents include THF, CH₂Cl₂, water or pyridine. The products (compounds of Formula XIX) can be isolated by extraction or, more conveniently, by removal of solvent, and are usually suitable for use in Step ii of Scheme 13 in crude form. Amides of Formula XVII can be used either in neutral form as depicted or as the salt form (typically as the HCl or CF₃CO₂H salt, among others). When the salt form of XVII is used, an additional one equivalent of base is used in Step i of Scheme 13.

In Step ii of Scheme 13, the amide of Formula XIX is converted to the diamine of

Formula XII by treatment with a reducing agent such as LiAlH₄, BH₃· HF or

BH₃·SMe₂ in a solvent such as THF or Et₂O at temperatures ranging from 0 °C to the reflux temperature of the solvent. Typical reaction times range from 0.5 h to 2 days.

Analogous procedures are well-known in the literature (see e.g., Synthesis, (1981), 441).

When R¹² is CH₃ and R¹³ is H, then XVII is alanine amide. The use of either the

D- or the L- form of alanine amide of Formula XVII or its salt provides a convenient means of obtaining enantiomerically enriched forms of diamines of Formula XII. When compounds of Formula II are prepared as described for Scheme 10 reactions using enantiomerically enriched forms of compounds of Formula XII, the compounds of

Formula II are obtained in enantiomerically enriched form. When compounds of

Formula I are prepared as described for Scheme 1 reactions using enantiomerically enriched forms of compounds of Formula II, the compounds of Formula I are obtained in enantiomerically enriched form.

Alternatively, diamines of Formula XII can be obtained in enantiomerically enriched forms by resolution with enantiomeric acids, such as tartaric acid. Such resolutions are well-known to one skilled in the art (see e.g., Synthesis, (1991), 789 for a related example).

Amines of Formula III can be prepared by the reaction of a silyl halide or germanyl halide of Formula XX with an excess of ammonia as shown in Scheme 14. These transformations typically involve the addition of compounds of Formula XX to anhydrous, liquid ammonia (2 to 100 equivalents) at temperatures ranging from -78 to 100 °C. In cases where temperatures greater than -33 °C are required, the reactions are carried out in a sealed, high pressure apparatus. Usually no solvent is required; however, solvents such as THF or diethyl ether are sometimes used. Reactions generally require

0.5 h to 72 h for completion. Typical work-up procedures usually involve the evaporation of excess ammonia, precipitation of ammonium halide by addition of ether, and removal of solvent. One skilled in the art will recognize that there are many alternative methods for converting halides of Formula XX to primary amines of

Formula III. References for a variety of procedures can be found in March, Adv. Org.

Chem., 4th Ed., pp 1276-7.

Silanes and germanes of Formula XX can be prepared by the reaction of organolithium or Grignard reagents of Formula XXI with chlorosilanes or

chlorogermanes of Formula XXII as depicted in Scheme 15. These reactions typically involve the mixture of equimolar amounts of compounds of Formulas XXI and XXII in organic solvents such as pentane, hexane, THF, ether and the like at temperatures ranging from -78 to 25 °C for times typically ranging from 2 h to 4 days.

Chlorosilanes and chlorogremanes of Formula XXII can be prepared by treatment of dichlorides of Formula XXIII with one molar equivalent of an organometallic reagent of Formula XXIV as depicted in Scheme 16. Conditions for Scheme 16 reactions are analogous to those described for Scheme 15 reactions. The preparation of compounds of Formula XX where R⁴ is equal to R⁵ can be achieved by the use of two equivalents of compounds of Formula XXIV in procedures depicted in Scheme 16.

Compounds of Formula XX where R⁴, R⁵ and R⁶ are identical can be prepared by the reaction of trichlorides of Formula XXV with three equivalents of organometallic compounds of Formula XXIV as shown in Scheme 17. Conditions for Scheme 17 reactions are analogous to those described for Scheme 15 reactions.

Compounds of Formula XX where R⁴ is an alkoxy or phenoxy group can be prepared by the reaction of an alcohol or phenol of Formula XXVI with a chlorosilane or chlorogermane of Formula XXII in the presence of a base such as triethylamine, pyridine or NaH as depicted in Scheme 18.

Procedures for the formation of ethers XX (R⁴ is alkoxy or phenoxy) are well-known to one skilled in the art (see, e.g., Org. Synth., 69, 96; J. Chem. Soc. Chem. Commun. (1988) 802; J. Organomet. Chem., (1970), 22, 599.)

Silanes and germanes of Formula XX where R⁴ and R⁵ are alkoxy or phenoxy can be prepared by the reaction of dichlorides of Formula XXIII with two equivalents of alcohols of Formula XXVI in the presence of a base using procedures analogous to those described for Scheme 18 reactions. Similarly, compounds of Formula XX where R⁴, R⁵ and R⁶ are alkoxy or phenoxy can be prepared by the reaction of trichlorosilanes or trichlorogermanes of Formula XXV with three equivalents of an alcohol of

Formula XXVI in the presence of a base using procedures analogous to those described for Scheme 18 reactions.

One skilled in the art will recognize that a wide variety of alternative procedures for the preparation of compounds of Formulae XX, XXII, XXIII and XXV are known in the art. Leading references concerning silanes include, e.g., Fleming, I., Organosilicon Chemistry, in Comprehensive Organic Chemistry, (1979), 3, 541; Colvin, E., Silicon in Organic Synthesis, Butterworths, Boston, (1981); and Pawlenko, S., Organosilicon Chemistry, Walter de Gruyter, New York, (1986). Leading references for germanes include, e.g., Rivière, P., et. al., Germanium, In Comprehensive Organometallic Chemistry, (1982), 2, 399; Lesbre, M., et. al, The Organic Compounds of Germanium, Wiley, London, (1971).

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. In these instances, the incorporation of

protection/deprotection sequences into the synthesis will aid in obtaining the desired products. The use and choice of the protecting group will be apparent to one skilled in chemical synthesis.

EXAMPLE 1

Step A: Methyl N-IY6-chloro-3-pyridinyl)carbonyll-alanine

A solution of 50.5 g (0.29 mol) of 6-chloronicotinyl chloride and 290 mL of CH₂Cl₂ was added to a solution of 60 g (0.43 mol) of DL-alanine methyl ester hydrochloride and 290 mL of saturated aqueous sodium bicarbonate solution. Then, 5 mL of aliquat 336 (Aldrich) was added and the resulting two-phase mixture was stirred rapidly at 25 °C for 24 h. The resulting mixture was partitioned between CH₂Cl₂ and saturated NaHCO₃. The aqueous layer was extracted with three portions of CH₂Cl₂. The combined organics were washed twice with saturated NaHCO₃, dried over MgSO₄ and concentrated to give 56.1 g of the title compound as a viscous yellow oil. ¹H NMR (300 MHz, CDCl₃) δ 8.82 (d,J=2.4Hz,1H), 8.10 (dd,1H), 7.41 (d,1H), 7.10 (br d,1H), 4.78 (quintet, 1H), 3.80 (s,3H), 1.53 (d,3H). Step B: 6-Chloro-N-[1-(aminocarbonyl)-ethyl]-3-pyridine carboxamide

A solution of 50.5 g (0.21 mol) of the product from Step A and 150 mL of anhydrous MeOH was added to 575 mL of 15% anhydrous ammonia in anhydrous methanol. The resulting solution was stirred at room temperature for 48 h. The solid product was removed by filtration, washed with ethanol and dried under vacuum to give 43.5 g of the title compound as a white solid; m.p. >220 °C. ¹H NMR (400 MHz, (CH₃)₂SO-d₆) δ 8.87 (apparent s,1H), 8.79 (d,1H), 8.29 (d,1H), 7.65 (d,1H), 7.45 (br s,1H), 7.03 (br s,1H), 4.41 (quintet,1H), 1.33 (d,3H).

Step C: N²-[(6-chloro-3-pyridinyl)-methyl]-1,2-propanediamine

Borane-methyl sulfide complex (18.7 mL, 0.19 mol) was added dropwise to a mechanically stirred mixture of 8.5 g (0.04 mol) of the product from Step B and 112 mL of THF at 50-60°C. The resulting orange-yellow suspension was refluxed for 2 h, cooled to room temperature and quenched by the careful dropwise addition of 62 mL of 6 N HC1. The resulting pale yellow mixture was stirred at room temperature for 24 h and then was washed with three portions of ether. The aqueous layer was basified with 25 mL of 50% NaOH (added with cooling) and extracted with 3 x 150 mL of 2: 1 methylene chloride-chloroform solution. Combined organic layers were dried (K₂CO₃) and concentrated to give 3.5 g of the title compound as a yellow oil. ¹H NMR (400 MHz,CDCl₃) δ 8.33 (apparent s,1H), 7.69 (d,1H), 7.30 (d,1H), 3.78 (ABq,2H), 2.75 (d,1H), 2.63 (dd,1H), 2.53 (dd,1H), ca. 1.50 (br s,3H), 1.07 (d,3H).

Step D: 2-Chloro-5-[[5-methyl-2-(nitromethylene')-1-imidazolidinyl]methyl]pyridine A suspension of 2.5 g (0.013 mol) of the product from Step C, 1.6 g (0.009 mol) of 1,1-bis(methylthio)-2-nitroethylene and 63 mL of anhydrous EtOH was heated at reflux for 3 h and was then allowed to stand at 24°C for 72 h. The resulting mixture was concentrated and chromatographed on silica gel using 15:1:0.1 CH₂Cl₂-EtOH-30% NH₄OH to give 0.70 g of the title compound as a yellow solid; m.p. 127-131°C.

1H NMR (400 MHz,CDCl₃) δ 8.70 (br s,1H), 8.27 (s,1H), 7.56 (d,1H), 7.35 (d,1H), 6.56 (s,1H), 4.33 (ABq,2H), 3.95-3.85 (m,2H), 3.45-3.35 (m,1H), 1.33 (d,3H).

Step E: 1-[(6-Chloro-3-pyridinyl)methyl]-1,2,3,5,6,7-hexahydro-2-methyl-8-nitro-6- [(trimethylsilyl)methyl]imidazo[1,2-c]pyrimidine (Compound 1)

A mixture of 0.5 g (1.9 mmol) of the product from Step D, 0.31 mL (4.1 mmol) of 37% aqueous formaldehyde, 0.21 g (2.1 mmol) of trimethylsilyl methylamine and 4 mL of ethanol was stirred at room temperature for 18 h. The resulting mixture was concentrated and the yellow residue was triturated with diethyl ether and filtered to give 0.32 g of the title compound as a yellow solid, m.p. 112-115 °C. ¹H NMR

(300 MHz,CDCl₃) δ 8.30 (s,1H), 7.81 (d,1H), 7.30 (d,1H), 5.04 (1/2ABq,1H), 3.98-3.68 (m,6H), 3.23 (dd,1H), 1.94 (s,2H), 1.26 (d,3H), 0.08 (s,9H). EXAMPLE 2

Step A: 2-Nitromethylene-imidazolidine

A suspension of 1,1-bis(methylthio)-2-nitroethylene (125 g, 0.76 mol), ethylenediamine (50.6 mL, 0.76 mol) and ethanol (757 mL) was heated at reflex for 4 h. The resulting mixture was cooled to 5°C and filtered. The solids were washed with cold ethanol and dried under vacuum to yield 102.5 g of a tan solid. ¹H NMR (200 MHz, Me₂SO-d₆) δ 8.27 (br s,2H), 6.33 (s,1H), 3.58 (s,4H).

Step B: 1,2,3,5,6,7-Hexahydro-8-nitro-6-[(trimethylsilyl)methyl]- imidazo[1,2-c]pyrimidine

A suspension of 0.98 g (7.6 mmol) of the product from Step A, 1.26 mL

(16.7 mmol) of 37% aqueous formaldehyde and 15 mL of ethanol was treated with 1.11 mL (8.3 mmol) of trimethylsilyl methylamine at room temperature. After 18 h, the resulting solution was concentrated to give 1.85 g of a yellow solid. ¹H NMR

(400 MHz,CDCl₃) δ 8.33 (br s,1H), 4.00 (s,2H), 3.80 (overlapping t, 2H and s,2H), 3.66 (t,2H), 2.14 (s,2H), 0.10 (s,9H).

Step C: 1-[(6-Chloro-3-pyridinyl)methyll-1,2,3,5,6,7-hexahydro-8-nitro-6- [(trimethylsilyl)methyl]-imidazo[1,2-c]pyrimidine

A mixture of 0.5 g (2.0 mmol) of the product from Step B, 0.8 g (3.9 mmol) of 6-chloro-3-chloromethyl-pyridine hydrochloride, 0.004 g (0.1 mmol) of tetra-n-butyl ammonium iodide, 6.4 mL of 50% aqueous KOH and 8.4 mL of methylene chloride was stirred vigorously for 24h. The resulting mixture was poured into water and extracted with 3 portions of methylene chloride. The combined organic layers were washed with saturated aqueous sodium bicarbonate, dried (K₂CO₃) and concentrated. The crude product was triturated with diethyl ether and filtered to give 0.34 g of the title compound as a yellow solid, m.p. 145.5- 147.0°C. ¹H NMR (400 MHz,CDCl₃) δ 8.35 (d,1H), 7.90 (dd,1H), 7.33 (d,1H), 4.86 (s,2H), 3.90 (s,2H), 3.77 (s,2H), 3.68-3.55 (m,4H), 2.02 (s,2H), 0.10 (s,9H).

By the general procedures described herein, or obvious modifications thereof, the compounds of Tables 1-16 and Index Tables A-D can be prepared. The compounds of Table 1, line 1 can be referred to as 1-1, 1-2, 1-3 and 1-4 (as designated by line and column). All the other specific compounds covered in these Tables can be designated in an analogous fashion. In Tables 1-16 and Index Tables A-D, the following notations have been used:

The following additional notations have been used to represent various embodiments of Q in Tables 15 and 16: Q-1 = 6-Cl-3-pyridyl, Q-2 = 5,6-dichloro-3-pyridyl, Q-3 =

2-chloro-5-thiazolyl, Q-4 = 3-chloro-5-isoxazolyl and Q-5 = CH₃SCH₂-.

Formulation/Utility

Compounds of this invention will generally be used in formulation with an agriculturally suitable carrier comprising a liquid or solid diluent. Useful formulations include dusts, granules, baits, pellets, solutions, suspensions, emulsions, wettable powders, emulsifiable concentrates, dry flowables and the like, consistent with the physical properties of the active ingredient, mode of application and environmental factors such as soil type, moisture and temperature. 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 100 weight percent.

Weight Percent

Active

Ingredient Diluent Surfactant

Wettable Powders 5-90 0-74 1-10

Oil Suspensions, Emulsions, 5-50 40-95 0-15

Solutions, (including Emulsifiable

Concentrates)

Dusts 1-25 70-99 0-5

Granules, Baits and Pellets 0.01-99 5-99.99 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 and solvents are described in Marsden, Solvents Guide, 2nd Ed., Interscience, New York, 1950. 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.

Solutions are prepared by simply mixing the ingredients. Fine solid compositions are made by blending and, usually, grinding as in a hammer mill or fluid energy mill. Water-dispersible granules can be produced by agglomerating a fine powder composition; see for example, Cross et al., Pesticide Formulations, Washington, D.C., 1988, pp 251-259. Suspensions are prepared by wet-milling; see, for example, U.S. 3,060,084. Granules and pellets can be made by spraying the active material upon preformed granular carriers or by agglomeration techniques. See Browning, "Agglomeration", Chemical Engineering, December 4, 1967, pp 147-148, Perry's Chemical Engineer's Handbook, 4th Ed., McGraw-Hill, New York, 1963, pages 8-57 and following, and WO 91/13546.

For further information regarding the art of formulation, see 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; and Hance et al., Weed Control Handbook, 8th Ed., Blackwell Scientific Publications, Oxford, 1989.

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

Wettable Powder

Compound 1 65.0%

dodecylphenol polyethylene glycol ether 2.0%

sodium ligninsulfonate 4.0%

sodium silicoaluminate 6.0%

montmorillonite (calcined) 23.0%.

Example B

Granule

Compound 1 10.0%

attapulgite granules (low volatile

matter, 0.71/0.30 mm; U.S.S. No.

25-50 sieves) 90.0%.

Example C

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 D

Emulsifiable Concentrate

Compound 1 20.0%

blend of oil soluble sulfonates

and polyoxyethylene ethers 10.0%

isophorone 70.0%. The compounds of this invention exhibit activity against a wide spectrum of foliar-feeding, fruit-feeding, stem or root feeding, seed-feeding, aquatic and

soil-inhabiting arthropods (term "arthropods" includes insects, mites and nematodes) which are pests of growing and stored agronomic crops, forestry, greenhouse crops, ornamentals, nursery crops, stored food and fiber products, livestock, household, and public and animal health. Those skilled in the art will appreciate that not all compounds are equally effective against all growth stages of all pests. Nevertheless, all of the compounds of this invention display activity against pests that include: eggs, larvae and adults of the Order Lepidoptera; eggs, foliar-feeding, fruit-feeding, root-feeding, seed-feeding larvae and adults of the Order Coleoptera; eggs, immatures and adults of the Orders Hemiptera and Homoptera; eggs, larvae, nymphs and adults of the Order Acari; eggs, immatures and adults of the Orders Thysanoptera, Orthoptera and

Dermaptera; eggs, immatures and adults of the Order Diptera; and eggs, junveniles and adults of the Phylum Nematoda. The compounds of this invention are also active against pests of the Orders Hymenoptera, Isoptera, Siphonaptera, Blattaria, Thysanura and Psocoptera; pests belonging to the Class Arachnida and Phylum Platyhelminthes. Specifically, the compounds are active against southern corn rootworm (Diabrotica undecimpunctata howardi), aster leafhopper (Mascrosteles fascifrons), boll weevil (Anthonomus grandis), two-spotted spider mite (Tetranychus urticae), fall armyworm (Spodoptera frugiperda), black bean aphid (Aphis fabae), green peach aphid (Myzus persica), cotton aphid (Aphis gossypii), Russian wheat aphid (Diuraphis noxia), English grain aphid (Sitobion avenae), tobacco budworm (Heliothis virescens), rice water weevil (Lissorhoptrus oryzophilus), rice leaf beetle (Oulema oryzae), whitebacked planthopper (Sogatellafurcifera), green leafhopper (Nephotettix cincticeps), brown planthopper (Nilaparvata lugens), small brown planthopper (Ixiodelphax striatellus), rice stem borer (Chilo suppressalis), rice leafroller (Cnaphalocrocis medinalis), black rice stink bug (Scotinophara lurida), rice stink bug (Oebalus pugnax), rice bug

(Leptocorisa chinensis), slender rice bug (Cletus puntiger), and southern green stink bug (Nezara viridula). The compounds are active on mites, demonstrating ovicidal, larvicidal and chemosterilant activity against such families as Tetranychidae including Tetranychus urticae, Tetranychus cinnabarinus, Tetranychus mcdanieli, Tetranychus pacificus, Tetranychus turkestani, Byrobia rubrioculus, Panonychus ulmi, Panonychus citri, Eotetranychus carpini borealis, Eotetranychus, hicoriae, Eotetranychus sexmaculatus, Eotetranychus yumensis, Eotetranychus banksi and Oligonychus pratensis; Tenuipalpidae including Brevipalpus lewisi, Brevipalpus phoenicis,

Brevipalpus calif ornicus and Brevipalpus obovatus; Eriophyidae including

Phyllocoptruta oleivora, Eriophyes sheldoni, Aculus cornutus, Epitrimerus pyri and Eriophyes mangiferae. See WO 90/10623 and WO 92/00673 for more detailed pest descriptions. Compounds of this invention can also be mixed with one or more other insecticides, fungicides, nematocides, bactericides, acaricides, growth regulators, chemosterilants, semiochemicals, repellants, attractants, pheromones, feeding stimulants or other biologically active compounds to form a multi-component pesticide giving an even broader spectrum of agricultural protection. Examples of other agricultural protectants with which compounds of this invention can be formulated are: insecticides such as avermectin B, monocrotophos, carbofuran, tetrachlorvinphos, malathion, parathion-methyl, methomyl, chlordimeform, diazinon, deltamethrin, oxamyl, fenvalerate, esfenvalerate, permethrin, profenofos, sulprofos, triflumuron,

diflubenzuron, methoprene, buprofezin, thiodicarb, acephate, azinphosmethyl, chlorpyrifos, dimethoate, fipronil, flufenprox, fonophos, isofenphos, methidathion, metha-midophos, phosmet, phosphamidon, phosalone, pirimicarb, phorate, terbufos, trichlorfon, methoxychlor, bifenthrin, biphenate, cyfluthrin, tefluthrin, fenpropathrin, fluvalinate, flucythrinate, tralomethrin, imidacloprid, metaldehyde and rotenone;

fungicides such as carbendazim, thiuram, dodine, maneb, chloroneb, benomyl, cymoxanil, fenpropidine, fenpropimorph, triadimefon, captan, thiophanate-methyl, thiabendazole, phosethyl-Al, chlorothalonil, dichloran, metalaxyl, captafol, iprodione, oxadixyl, vinclozolin, kasugamycin, myclobutanil, tebuconazole, difenoconazole, diniconazole, fluquinconazole, ipconazole, metconazole, penconazole, propiconazole, uniconzole, flutriafol, prochloraz, pyrifenox, fenarimol, triadimenol, diclobutrazol, copper oxychloride, fυralaxyl, folpet, flusilazol, blasticidin S, diclomezine, edifenphos, isoprothiolane, iprobenfos, mepronil, neo-asozin, pencycuron, probenazole, pyroquilon, tricyclazole, validamycin, and flutolanil; nematocides such as aldoxycarb, fenamiphos and fosthietan; bactericides such as oxytetracyline, streptomycin and tribasic copper sulfate; acaricides such as binapacryl, oxythioquinox, chlorobenzilate, dicofol, dienochlor, cyhexatin, hexythiazox, amitraz, propargite, tebufenpyrad and fenbutatin oxide; and biological agents such as entomopathogenic bacteria, virus and fungi.

In certain instances, combinations with other arthropodicides having a similiar spectrum of control but a different mode of action will be particularly advantageous for resistance management.

Arthropod pests are controlled and protection of agronomic, horticultural and specialty crops, animal and human health is achieved by applying one or more of the compounds of this invention, in an effective amount, to the environment of the pests including the agronomic and/or nonagronomic locus of infestation, to the area to be protected, or directly on the pests to be controlled. Thus, the present invention further comprises a method for the control of foliar and soil inhabiting arthropods and nematode pests and protection of agronomic and/or nonagronomic crops, comprising applying one or more of the compounds of Formula I, or compositions containing at least one such compound, in an effective amount, to the environment of the pests including the agronomic and/or nonagronomic locus of infestation, to the area to be protected, or directly on the pests to be controlled. A preferred method of application is by spraying. Alternatively, granular formulations of these compounds can be applied to the plant foliage or the soil. Other methods of application include direct and residual sprays, aerial sprays, seed coats, microencapsulations, systemic uptake, baits, eartags, boluses, foggers, fumigants, aerosols, dusts and many others. The compounds can be incorporated into baits that are consumed by the arthropods or in devices such as traps and the like.

The compounds of this invention can be applied in their pure state, but most often application will be of a formulation comprising one or more compounds with suitable carriers, diluents, and surfactants and possibly in combination with a food depending on the contemplated end use. A preferred method of application involves spraying a water dispersion or refined oil solution of the compounds. Combinations with spray oils, spray oil concentrations, spreader stickers, adjuvants, and synergists and other solvents such as piperonyl butoxide often enhance compound efficacy.

The rate of application required for effective control will depend on such factors as the species of arthropod to be controlled, the pest's life cycle, life stage, its size, location, time of year, host crop or animal, feeding behavior, mating behavior, ambient moisture, temperature, and the like. Under normal circumstances, application rates of about 0.01 to 2 kg of active ingredient per hectare are sufficient to control pests in agronomic ecosystems, but as little as 0.001 kg/hectare may be sufficient or as much as 8 kg hectare may be required. For nonagronomic applications, effective use rates will range from about 1.0 to 50 mg/square meter but as little as 0.1 mg/square meter may be sufficient or as much as 150 mg/square meter may be required.

The following TESTS demonstrate the control efficacy of compounds of this invention on specific pests. "Control efficacy" represents inhibition of arthropod development (including mortality) that causes significantly reduced feeding. The pest control protection afforded by the compounds is not limited, however, to these species. See Index Tables A-E for compound descriptions.

The following additional notations have been used to represent various embodiments of Q in Table C: Q-1 = 6-Cl-3-pyridyl, Q-2 = 5,6-dichloro-3-pyridyl, Q-3 = 2-chloro-5-thiazolyl and Q-5 = CH₃SCH₂-.

Index Table E

¹H NMR (CDCI₃) DATA ^(a)

Cmpd. No.

7 4.47-4.36 (m,1H), 4.02 (d,2H), 3.90-3.73 (m,4H), 3.49 (dt, 1H),

3.22 (dd,1H), 2.82-2.68 (m,2H), 2.12 (s,3H), 2.08 (ABq,2H),

1.39 (d,3H), 0.10 (s,9H).

13 8.30 (d,1H), 7.69 (dd,1H), 7.32 (d,1H), 4.50 (d,1H), 4.18 (d,1H),

3.60-3.40 (m,5H), 3.32-3.21 (m,1H), 2.99 (s,3H), 1.97 (s,2H), 1.19 t,3H), 0.10 (s,9H).

20 (300 MHz) 8.31 (d,1H), 7.78 (dd,1H), 7.50 (dd,2H), 7.40-7.32 (m,3H),

7.30 (d,1H), 5.08 (d,1H), 4.65 (d,1H), 3.9-3.65 (m,5H), 3.18 (t,1H), 2.83 (dd,1H), 2.19 (ABq,2H), 1.19 (d,3H), 0.39 (s,3H), 0.35 (s,3H).

21 (300 MHz) 8.32 (d,1H), 7.79 (dd,1H), 7.52 (dd,2H), 7.42-7.35 (m,3H),

7.30 (d,1H), 5.07 (d,1H), 4.66 (d,1H), 3.9-3.65 (m,5H), 3.17 (t,1H), 2.83 (dd.1H), 2.19 (ABq,2H), 1.19 (d,3H), 0.39 (s,3H), 0.35 (s,3H).

22 (300 MHz) 8.30 (s,1H), 7.80 (d,1H), 7.50-7.40 (m,2H), 7.40-7.30

(m,3H), 7.30 (d,1H), 5.00 (d,1H), 4.75 (d,1H), 3.90-3.65 (m,6H),

3.20-3.10 (m,1H), 2.40-2.30 (m,2H), 1.60-1.45 (m,2H), 1.24 (d,3H), 0.80-0.70 (m,2H), 0.28 (s,6H).

26 8.35 (s,1H), 7.85 (d,1H), 7.60 (d,1H), 7.55-7.50 (m,6H), 7.43-7.35

(m,9H), 4.79 (s,2H), 3.84 (s,2H), 3.78 (s,2H), 3.51 (s,4H), 2.5 (t,2H), 1.80-1.65 (m,2H), 1.45-1.35 (m,2H).

27 (300 MHz) 7.52 (dd,2H), 7.45 (s,1H), 7.42-7.35 (m,3H), 4.93 (s,2H),

3.81 (s,2H), 3.78 (s,2H), 3.54 (distorted t,2H), 3.14 (distorted t,2H), 2.28 (s,2H), 0.38 (s,6H). 29 (300 MHz) 7.57 (dd,2H), 7.39 (m,2H), 4.40 (dt?,1H), 3.93-3.82 (m,4H),

3.72 (d,1H), 3.45 (m,1H), 3.34 (t,1H), 2.85 (dd,1H), 2.8-2.6 (m,2H), 2.35 (ABq,2H), 2.10 (s,3H), 1.31 (d,3H), 0.40 (s,3H), 0.36 (s,3H).

32 (300 MHz) 8.26 (s,1H), 8.07 (s,1H), 4.85 (s,2H), 3.91 (s,2H), 3.78

(s,2H), 3.63 (m,4H), 2.07 (s,2H), 0.96 (t,3H), 0.58 (q,2H), 0.09 (s,6H).

33 (300 MHz) 8.27 (s,1H), 8.05 (s,1H), 7.55 (m,2H), 7.40 (m,3H), 4.82

(s,2H), 3.82 (s,2H), 3.79 (s,2H), 3.46 (m,2H), 3.15 (distorted t,2H), 2.31 (s,2H), 0.40 (s,6H).

35 8.30 (s,1H), 7.64 (apparent d,1H), 7.54 (m,2H), 7.38 (m,3H), 7.31

(d,1H), 4.59 (br s,2H), 3.72 (m,4H), 3.27 (m,2H), 3.11 (t,2H), 2.17

(s,2H), 1.97 (m,2H), 0.39 (s,6H).

(a) Unless indicated otherwise, spectra were obtained in CDCl₃ at 400MHz.

Chemical shift values (δ) are relative to Me₄Si = 0.00ppm. s = singlet, d = doublet, t = triplet, q = quartet, m = multiplet.

TEST A

Fall Armyworm

Test units, each consisting of a H.I.S. (high impact styrene) tray with 16 cells were prepared. Wet filter paper and approximately 8 cm² of lima bean leaf was placed into twelve of the cells. A 0.5 cm layer of wheat germ diet was placed into the four remaining cells. Fifteen to twenty third-instar larvae of fall armyworm (Spodoptera frugiperda) were placed into a 230 mL (8 ounce) plastic cup. Solutions of each of the test compounds in 75/25 acetone/distilled water solvent were sprayed into the tray and cup. Spraying was accomplished by passing the tray and cup on a conveyer belt directly beneath a flat fan hydraulic nozzle which discharged the spray at a rate of 0.55 kg of active ingredient per hectare (about 0.5 pounds per acre) at 207 kPa (30 p.s.i.). The insects were transferred from the 230 mL cup to the H.I.S. tray (one insect per cell). The trays were covered and held at 27°C and 50% relative humidity for 48 h, after which time readings were taken on the twelve cells with lima bean leaves. Of the compounds tested, the following gave control efficacy levels of 80% or greater: 1, 2, 3, 4*, 5*, 6, 14*, 19*, 27*, 28*, 29*, 30*, 31* and 27*.

* - tested at 0.14 kg/ha.

TEST B

Southern Corn Rootworm

Test units, each consisting of a 230 mL (8 ounce) plastic cup containing a 2.54 cm² plug (1 square inch) of a wheatgerm diet, were prepared. The test units were sprayed as described in TEST A with individual solutions of the test compounds. After the spray on the cups had dried, five second-instar larvae of the southern corn rootworm (Diabrotica undecimpunctata howardi) were placed into each cup. The cups were held at 27°C and 50% relative humidity for 48 h, after which time mortality readings were taken. Of the compounds tested, the following gave control efficacy levels of 80% or greater: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 14*, 15*, 16*, 20*, 21*, 22*, 24*, 26*, 27*, 28*, 30*, 32* and 34*.

* - tested at 0.14 kg/ha.

TEST C

Aster Leafhopper

Test units were prepared from a series of 350 mL (12 ounce) cups, each containing oat (Avena sativa) seedlings in a 2.54 cm (1 inch) layer of sterilized soil. The test units were sprayed as described in TEST A with individual solutions of the test compounds.

After the oats had dried from the spraying, 10 to 15 adult aster leafhoppers

(Mascrosteles fascifrons) were aspirated into each of the cups. The cups were covered with vented lids and held at 27°C and 50% relative humidity for 48 h, after which time mortality readings were taken. Of the compounds tested, the following gave mortality levels of 80% or higher: 1, 2, 3, 4, 5, 6, 7, 10, 11, 13, 14* and 16*, 19*, 20*, 21*, 23*,

24*, 25*, 26*, 27*, 28*, 29*, 30*, 31*, 32* and 34*.

* - tested at 0.14 kg/ha.

TEST D

Boll Weevil

Test units consisting of 260 mL (9 ounce) cups containing five adult boll weevils (Anthonomus grandis grandis) were prepared. The test units were sprayed as described in TEST A with individual solutions of the test compounds. Each cup was covered with a vented lid and held at 27°C and 50% relative humidity for 48 h, after which time mortality readings were taken. Of the compounds tested, the following gave mortality levels of 80% or higher: 2, 3, 4, 5, 6, 7, 10 and 16*.

* - tested at 0.14 kg/ha.

TEST E

Black Bean Aphid

Individual nasturtium leaves were infested with 10 to 15 aphids (all morphs and growth stages of Aphis fabae) and sprayed with their undersides facing up as described in TEST A. The leaves were then set in 0.94 cm (3/8 inch) diameter vials containing 4 mL of sugar solution (approximately 1.4 g per liter) and covered with a clear plastic 29 mL (1 ounce) cup to prevent escape of the aphids that drop from the leaves. The test units were held at 27°C and 50% relative humidity for 48 hours, after which time mortality readings were taken. Of the compounds tested, the following gave mortality levels of 80% or higher: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 13, 14*, 15* and 16*. 19*, 21*, 22*, 23*, 24*, 25*, 26*, 28*, 29*, 30*, 31*, 32* and 34*.

* - tested at 0.14 kg/ha. TEST F

Contact Activity Against Green Leafhopper Nymphs

Three rice (Oryza sativa) seedlings, 1.5 leaf stage and about 10 cm tall were transplanted into a 14 mL (1/2 ounce) plastic cup containing Kumiai Brown artificial soil. Seven milliliters of distilled water were then added to the cup. The test chemical was prepared by first dissolving the chemical in acetone and then adding water to produce a final test concentration of 75:25 (acetone: water). Four plastic cups, each cup serving as a replicate, were then placed on a spray chamber turntable. The cups were sprayed for 45 seconds with 50 mL of the chemical solution at a pressure of 2.0 kg/cm² with air atomizing spray nozzles. The turntable completes 7.5 rotations during the 45 second spray interval. After chemical application, the treated cups were held in a vented enclosure to dry for about 2 h. After drying, the cups were placed into conical shaped test units and the surface of the soil covered with 2 to 3 mm of quartz sand. Eight to ten 3rd-instar nymphs of the green leafhopper (Nephotettix cincticeps) were transferred into the test units using an aspirator. The test units were held at 27°C and 65% relative humidity. Counts of the number of live and dead nymphs were taken at 24 and 48 h post-infestation. Insects which cannot walk are classified as dead. Of the compounds tested, the following gave mortality levels of 80% or higher at 48 h at an application rate equivalent to 0.05 kilograms per hectare: 1, 2, 3 4, 5, 6, 7 and 8.

TEST G

Contact Activity Against Brown Planthopper Nymphs

Three rice (Oryza sativa) seedlings, 1.5 leaf stage and about 10 cm tall were transplanted into a 14 mL (1/2 ounce) plastic cup containing Kumiai Brown artificial soil. Seven milliliters of distilled water was then added to the cup. The test chemical was prepared by first dissolving the chemical in acetone and men adding water to produce a final test concentration of 75:25 (acetone:water). Four plastic cups, each cup serving as a replicate, were then placed on a spray chamber turntable. The cups were sprayed for 45 seconds with 50 mL of the chemical solution at a pressure of 2.0 kg/cm² with air atomizing spray nozzles. The turntable completes 7.5 rotations during the 45 second spray interval. After chemical application, treated cups were held in a vented enclosure to dry for about 2 h. After drying, the cups were placed into conical shaped test units and the surface of the soil covered with 2 to 3 mm of quartz sand. Eight to ten 3rd-instar nymphs of the brown planthopper (Nilaparvata lugens) were then transferred into the test units using an aspirator. The test units were held at 27°C and 65% relative humidity. Counts of the number of live and dead nymphs are taken at 24 and 48 h post-infestation. Insects which cannot walk are classified as dead. Of the compounds tested, the following gave mortality levels of 80% or higher at 48 h at an application rate equivalent to 0.05 kilograms per hectare: 1, 2, 3, 4, 5, 6, 7, 8 and 9.

Claims

1. A compound of the formula

wherein

X is selected from the group Si and Ge;

R¹ and R³ are independently selected from the group H, C₁-C₁₀ alkyl, C₂-C₁₀ alkenyl or C₂-C₁₀ alkynyl, each group optionally substituted with 1-2 substituents independently selected from the group halogen, CN, C(O)R⁷, C(S)R⁷, NO₂, OH, SC(O)R⁷, SC(S)R⁷, OC(O)R⁷, OC(S)R⁷, NR⁸C(O)R⁷, NR⁸C(S)R⁷, SH, Si(R⁸)(R⁹)(R¹⁰), C₁-C₄ alkoxy, C₁-C₄ haloalkoxy, C₁-C₄ alkylthio, C₁-C₄ alkylamino, C₂-C₈ dialkylamino, C₃-C₈ cycloalkyl and phenyl optionally substituted with 1-3 substituents independently selected from W¹; C₃-C₈ cycloalkyl optionally substituted with 1-3 substituents independently selected from the group halogen, C₁-C₂ alkyl and C₁-C₂ haloalkyl; C(O)R¹¹; C(S)R¹¹; phenyl optionally substituted with 1-3 substituents independently selected from W¹; C₁-C₃ alkyl substituted with a 5- or 6-membered aromatic ring, attached through carbon or nitrogen, containing 1 to 4 heteroatoms independently selected from the group 0-4 nitrogen, 0-1 oxygen, and 0-1 sulfur, the ring optionally substituted with 1-3 substituents independently selected from W¹ ; and a 5- or 6-membered aromatic ring, attached through carbon or nitrogen, containing 1 to 4 heteroatoms independently selected from the group 0-4 nitrogen, 0-1 oxygen, and 0-1 sulfur, the ring optionally substituted with 1-3 substituents independently selected from W¹;

C₂-C₆ haloalkenyl, C₂-C₆ alkynyl, C₂-C₆ haloalkynyl, C₃-C₇ cycloalkyl, C₃-C₇ halocycloalkyl and C₄-C₇ cycloalkylalkyl, each group optionally substituted with 1-3 substituents independently selected from W; or R² and R³ can be taken together as CH₂CH₂ and CH₂CH₂CH₂ each group optionally substituted with 1-2 CH₃;

R⁷ is selected from the group H, NH₂, OH, C₁-C₆ alkyl, C₁-C₆ haloalkyl, C₁-C₆ alkoxy, C₁-C₆ haloalkoxy, C₁-C₆ alkylthio, C₁-C₄ alkylamino, C₂-C₈ dialkylamino and phenyl optionally substituted with 1-3 substituents independently selected from W^l ;

R⁸ is H; or R⁸ is selected from the group C₁-C₁₀ alkyl, C₂-C₁₀ alkenyl, C₂-C₁₀ alkynyl, C₁-C₁₀ alkoxy, phenoxy, phenyl and naphthyl, each group optionally substituted with 1-3 substituents independently selected from W¹;

alkenyl, C₂-C₁₀ alkynyl, C₁-C₁₀ alkoxy, phenoxy, phenyl and naphthyl, each group optionally substituted with 1-3 substituents independently selected from Wl; and OH;

W is selected from the group halogen, CN, NO₂, OH, C₁-C₆ alkyl, C₁-C₆

haloalkyl, C₁-C₆ alkoxy and C₁-C₆ haloalkoxy; and

W¹ is selected from the group halogen, CN, NO₂, C₁-C₂ alkyl, C₁-C₂ haloalkyl, C₁-C₂ alkoxy, C₁-C₂ haloalkoxy, C₁-C₂ alkylthio, C₁-C₂ haloalkylthio, C₁-C₂ alkylsulfonyl, C₁-C₂ haloalkylsulfonyl, C₁-C₄ alkylamino, C₂-C₈ dialkylamino and C₃-C₆ trialkylsilyl.

2. A compound according to Claim 1 wherein:

A is C₁-C₆ alkylene;

R¹ is C₁-C₃ alkyl substituted with a 5- or 6-membered aromatic ring, attached through carbon or nitrogen, containing 1 to 4 heteroatoms independently selected from the group 0-4 nitrogen, 0-1 oxygen, and 0-1 sulfur, the ring optionally substituted with 1-3 substituents independently selected from W¹; R⁴ is selected from the group C₁-C₁₀ alkyl and phenyl, each group optionally substituted with 1-3 substituents independently selected from W¹;

R⁵ and R⁶ are independently selected from the group C₁-C₁₀ alkyl and phenyl, each group optionally substituted with 1-3 substituents independently selected from W¹; and

W¹ is selected from the group halogen and C₁-C₂ haloalkyl.

3. A compound according to Claim 2 wherein:

X is Si;

R¹ is CH₂ substituted with pyridyl, thiazole or isoxazole, the ring

optionally substituted with 1-2 halogen or 1-2 methyl;

R² and R³ are taken together as CH₂CH₂ or CH₂CH₂CH₂ each group optionally substituted with 1-2 CH₃; and

R⁴, R⁵ and R⁶ are C₁-C₃ alkyl, C₁-C₃ alkoxy and phenyl.

4. A compound according to Claim 2 wherein:

X is Si;

R¹ is CH₂ substituted with pyridyl, thiazole or isoxazole, the ring

optionally substituted with 1-2 halogen;

R² is selected from the group H and C₁-C₃ alkyl; and

R⁴, R⁵ and R⁶ are C₁-C₃ alkyl, C₁-C₃ alkoxy and phenyl.

5. A compound according to Claim 3 which is:

1-[(6-chloro-3-pyridinyl)methyl]-1,2,3,5,6,7-hexahydro-2-methyl-8- nitro-6-[(trimethylsilyl)methyl]imidazo[1,2-c]pyrimidine.

6. A compound according to Claim 3 which is:

1-[(6-chloro-3-pyridinyl)methyl]-1,2,3,5,6,7-hexahydro-8-nitro- 6-[(trimethylsilyl)memyl]imidazo[l,2-c]pyrimidine.

7. An arthropodicidal composition comprising an arthropodicidally effective amount of a compound according to Claim 1 and a carrier therefor.

8. A method for controlling arthropods comprising contacting the arthropods or their environment with an arthropodicidally effective amount of a compound according to Claim 1.