CA1150271A

CA1150271A - 3-¬5-¬1-(alkyloxy or alkylthio)alkyl, alkynyl, alkenyl, or haloalkyl|-1,3,4- thiadiazol-2-yl|-4-hydroxy-1-methyl-2- imidazolidinones

Info

Publication number: CA1150271A
Application number: CA000357157A
Authority: CA
Inventors: Jerome M. Lavanish
Original assignee: PPG Industries Inc
Current assignee: PPG Industries Ohio Inc
Priority date: 1979-08-10
Filing date: 1980-07-28
Publication date: 1983-07-19
Also published as: FR2463138A1; ZW18480A1; IT1129241B; MA18930A1; ES494104A0; EG14324A; YU197880A; ZA804583B; RO80300A; BR8004985A; CS226018B2; ES8106726A1; AR227767A1; FR2463138B1; GB2055832A; DE3029729C2; PL226187A1; PT71681B; IT8068277A0; PL126910B1

Abstract

ABSTRACT OF THE DISCLOSURE
Compounds of general Formula I are disclosed:

(I) wherein:
X is oxygen or sulfur, R is an alkyl of up to four carbon atoms, an alkenyl of up to three carbon atoms, an alkynyl of up to three carbon atoms, or a haloalkyl selected from the group consisting of chloromethyl, bromomethyl, 2-chloro-ethyl, and 2-bromoethyl, and R1 is an alkyl of up to four carbon atoms.
These compounds are used in selective weed control at low rates of application. A method of preparation is also disclosed.

Description

Z7~

3-[5-[1-(ALKYLOXY OR ALKYLTHIO)ALKYL, ALKYNYL, ALKENYL, OR HALOALKYL]-1,3,4-THIADIAZOL-2-YL]
-4-HYDROXY-l-METHYL-2-IMIDAZOLIDINONES

BACKGROUND OF THE INVENTION
FIELD OF THE INVENTION
The invention relates to substituted 1,3,4-thiadiazol-2-yl-4-hydroxy-l-methyl-2-imidazolidinones, particularly to the 3-[5-[1-alkoxy or thioalkyl)alkyl, alkynyl, alkenyl or haloalkyl substituted]-1,3,4-thiadiazol-

2-yl]-4-hydroxy-177methyl-2-imidazolidinone compounds.

DESCRIPTION OF THE PRIOR ART
Imidazolidinones, as a class, are described in patents and chemical literature; none of which, however, teaches or discloses the novel herbicidal compounds described herein and their use to control the weeds described herein.

SUMMARY OF THE INVENTION
~77.
The invention described herein concerns compounds graphically represented by Formula I:

R~_ X--C S ~c~l3 R N
OH
wherein:
X is oxygen or sulfur, ;,~, llSC)Z71 R is an alkyl of up to four carbon atoms, an alkenyl of up to three carbon atoms, an alkynyl of up to three carbon atoms, or a haloalkyl selected from the group consisting of chloromethyl, bromomethyl, 2-chloroethyl, and 2-bromoethyl and R' is an alkyl of up to four carbon atoms; the intermediates graphically represented by Formulas III, IV and V:

R'--- X - C - ~ ~ ~ NH2 (III) R N

~' - X-- C - _ NCO (IV) H S H O
R'---X-- C ~ ~ ~ ~ --C-- N - CH2- CH - (OCH3)2 (V) wherein:
X, R and R' are defined as herein, as well as the process for making compounds of the described formulas. The compounds of Formula I are particularly useful for controlling weeds postemergence and preemergence and are selective to other weeds both postemergence and preemergence at low rates of applications; particularly the compound wherein X is oxygen, and R and R' are methyl. For example, the compound 3-[5-(l-meth-oxyethyl)-1,3,4-thiadiazol-2-yl]-4-hydroxy-1-methyl-2-imidazolidinone, where X is oxygen and R and R' are methyl, is useful for controlling noxious weeds 1~5V27~

such as: teaweed, jimsonweed, yellow foxtail, crabgrass, johnsongrass, coffeeweed, velvetleaf, morningglory wild oats and barnyardgrass, and i9 also safe on crops at low application rates.

DESCRIPTION OF THE PREFERRED EMBODIMENT
The novel agriculturally useful compounds described herein may be graphically represented by Formula I:

o R
OH
wherein:
X is oxygen or sulfur, and R is an alkyl of up to four carbon atoms, an alkenyl of up to three carbon atoms, an alkynyl of up to three carbon atoms, or a haloalkyl selected from the group consisting of chloromethyl, bromomethyl, 2-chloro-ethyl and 3-bromoethyl and R' is an alkyl of up to four carbon atoms.
Examples of compounds represented by Formula I are:

3-[5-[1-methylthioethyl]-1,3,4-thiadiazol-2-yl]-

4-hydroxy-1-methyl-2-imidazolidinone.
3-[5-[1-butylthio-2-bromoethyl]-1,3,4-thiadiazol-2-yl]-4-hydroxy-1-methyl-2-imidazolidinone.
3-[5-[1-t-butoxy-2-bromoethyl]-1,3,4-thiadiazol-2-yl]-4-hydroxy-1-methyl-2-imidazolidinone.
3-[5-[1-methoxy-3-chloropropyl]-1,3,4-thiadiazol-2-yl]-4-hydroxy 1-methyl-2-imidazolidinone.

~SI~Z7~

3-[5-[1-ethylthio-3-bromopropyl]-1,3,4-thiadiazol-2-yl]-4-hydroxy-1-methyl-2-imidazolidinone.
3-[5-[1-ethoxy-2-propynyl]-1,3,4-thiadiazol-2-yl]-4-hydroxy-1-methyl-2-imidazolidinone.
3-[5-[1-isopropylthio-2-butynyl]-1,3,4-thiadiazol-2-yl]-4-hydroxy-1-methyl-2-imidazolidinone.
3-[5-[1-isopropoxy-3-butynyl]-1,3,4-thiadiazol-2-yl]-4-hydroxy-1-methyl-2-imidazolidinone.

3-[5-[1-methoxy-2-propenyl]-1,3,4-thiadiazol-2-yl]-4-hydroxy-1-methyl-2-imidazolidinone. --3-[5-[1-methylthio-2-butenyl]-1,3,4-thiadiazol-2-yl]-4-hydroxy-1-methyl-2-imidazolidinone.

3-[5-[1-ethoxy-2-chloroethyl]-1,3,4-thiadiazol-2-yl]-4-hydroxy-1-methyl-2-imidazolidinone.

3-[5-[1-ethylthio-2-bromoethyl]-1,3,4-thiadiazol-2-yl]-4-hydroxy-1-methyl-2-imidazolidinone.

3-[5-[1-propoxy-3-chloropropyl]-1,3,4-thiadiazol-2-yl]-4-hydroxy-1-methyl-2-imidazolidinone.

3-[5-[1-propylthio-3-bromopropyl]-1~3,4-thiadiazol-2-yl~-4-hydroxy-1-methyl-2-imidazolidinone.

3-[5-[1-isopropoxy-3-butenyl~-1,3,4-thiadiazol-2-yl]-4-hydroxy-1-methyl-2-imidazolidinone.

3-[5-[1-isopropylthio-1-pentenyl]-1,3,4-thiadiazol-2-yl]-4-hydroxy-1-methyl-2-imidazolidinone.

3-[5-[1-butoxy-1-(3-methylbutyl)]-1,3,4-thiadiazol-2-yl]-4-hydroxy-1-methyl-2-imidazolidinone.

3-[5-[1-butylthio-2-(2-methylbutyl)]-1,3,4-thiadiazol-2-yl]-4-hydroxy-1-methyl-2-imidazolidinone.

l~Z71 3-[5-[1-sec-butoxy-1-(2,2-dimethylpropyl)]-1,3,4-thiadiazol-2-yl]-4-hydroxy-1-methyl-2-imidazolidinone.
3-[5-[1-sec-butylthio-1-butyl]-1,3,4-thiadiazol-2-yl]-4-hydroxy-1-methyl-2-imidazolidinone.
3-[5-[1-t-butoxy-(2-methylpropyl)]-1,3,4-thiadiazol-2-yl]-4-hydroxy-1-methyl-2-imidazolidinone.
3-[5-[1-t-butylthiopropyl]-1,3,4-thiadiazol-2-yl]-4-hydroxy-1-methyl-2-imidazolidinone.
Although all of the compounds described herein are useful for the purpose described herein, some compounds are more useful than others.
Compounds in which R is an alkynyl, are of a general utility while compounds in which R is an alkenyl, are of better utility. Compounds in which R is a haloalkyl described herein are of high utility and of these, the pre-ferred compounds are those in which R is chloromethyl or bromomethyl.
Compounds in which R is an alkyl described herein, are highly preferred and especially preferred are compounds in which the alkyl is methyl, ethyl or isopropyl. R' is preferably methyl, and generally X is preferably oxygen.
The following compounds are the most preferred: 3-[5-(1-methylthioethyl)-1,3,4-thiadiazol-2-yl]-4-hydroxy-1-methyl-2-imidazolidinone and 3-[5-(1-methoxyethyl)-1,3,4-thiadiazol-2-yl]-4-hydroxy-1-methyl-2-imidazolidinone.

SYNTH~SIS OF THE COMPOUNDS
The synthesis of the compound proceeds according to the general reactions 1, 2, 3, 4 and 5 shown below:

K'---X-- M+ + Y-- C - C011 (1) (VI) / (VII) ~S~Z7~

H O S
R'--X--C--COH + POC13 + H2NCNHNH2 (2) 1. d ioxane, re f lux ( II ) L/ 2 . NaOEI/H20 R '-- X--C ~ NH2 ( 3 ) R

(III) /COC12 L/ ethyl acetate R'-- X--C ~ 12 (IV) ¦ CH3N--CH2-`CH(OcH3)2 a H O
R '--X--C ~1--C--~T--CH2CH ( OCH3 ) 2 ~,,/
8 (5) E~'-- X--C~ CH3 Oli ~SUZ~l Preparation of 5-Substituted 2-Amino-1,335-Thiadiazole The appropriate metal saLt M+ such as sodium, potassium or lithium of the appropriate alkylalcohol or alkylthiol graphically represented by Formula VI where R' and X are as described herein is reacted with a 2-halo substituted alkanoic acid (or its ester) graphically represented by Formula VII wherein R is as defined herein and Y is chlorine, bromine, or iodine, preferably bromine, is reacted as shown in reaction 1 to form the alpha substituted alkoxy or alkylthio carboxylic acid graphically represented by Formula II, wherein R, R' and X are as described herein.
The proper alpha substituted alkoxy or alkythio carboxylic acid of Formula II (typically 0.4-0.5 moles), an equimolar amount of thio-semicarbazide, and 30 milliliters of dry dioxane are charged into a 100 milliliter reactor equipped with a thermometer, an efficient stirrer, pressure equalized, addition funnel and a condenser-drying tube. The addition funnel is charged with approximately 10% excess of phosphorus oxychloride which is added drop-wise so as to maintain a reaction tempera-ture of 85-95 C and reartion occurs as shown by reaction equation 1. The mixture is then heated to reflux for about 1 hour, after which the solvent is flashed off using a vacuum such as a water aspirator. Water (50 milli-liters) is added to the residue to give an emulsion which is then made basic with a 50% sodium hydroxide solution. In those instances that a solid product is obtained (graphically represented by Formula III, wherein X and R are as described herein), the product is isolated by filtration and recrystallized when necessary. In other cases, the reaction mixture is extracted with ether, the ether layer is separated from the heavier layers, dried over magnesium sulfate, filtered and concentrated under vacuum to give the crude product represented as a viscous oil.

~150Z71 Preparation of the Isocyanate Dimers Five to 10 grams of the appropriate 2-amino-1,3,4-thiadiazole (graphically represented by Formula III is added to a solution of phosgene in ethylacetate, (or other suitable solvent) prepared by saturating 50 - 100 milliliters of solvent with phosgene at room temperature, then adding another 50 - 100 milliliters of solvent. The mixture is allowed to stir overnight at room temperature as shown by reaction equation 2 and then purged with nitrogen or argon to remove the unreacted phosgene. In those cases where a solid was obtained, the product (graphically represented by Formula IV which is an isocyanate dimer of the appropriate substituted 1,3,4-thiadiazole), was isolated by filtration and dried. In cases where no solid product is evident, the reaction mixture may be topped under vacuum to give the product as a viscous oil or glass.

Preparation of Acetal Ureas The appropriate isocyanate dimer of Formula IV and an equivalent amount of methylaminoacetaldehyde dimethylacetal were heated to reflux (5-15 minutes) in an inert solvent such as ether, benzene or toluene and the reaction proceeded as shown by reaction equation 3 so as to form the product graphically represented by Formula V. Some products may be produced as crystals directly from solution, but others may be induced by the addition of hexane. The product represented by graphic Formula V
may be purified such as by washing with ether or hexane or recrystallized from hexane/benzene or from ether/benzene or from ether/chloroform/benzene solutions. Those products or compounds that are represented by Formula V
obtained as oils need not be purified.

3.15~271 Preparation of the Compounds of Formula I
. . . _ _ _ The appropriate acetal urea of Formula V (approximately three to four grams) is added to 150-200 milLiliters of water containing 1.5-2 milliliters of concentrated hydrochloric acid. The mixture is stirred vigorously and heated to reflux, and reaction proceeds as shown by reaction equation 4. The hydrolysis is monitored by thin layer chromatography (alumina-ethylacetate) until complete and the product containing a compound of Formula I forms. The product, in some cases, may be crystallized directly from the reaction mixture upon cooling. In other cases, the compounds of Formula I are extracted with chloroform and isolated by stripping the solvent under vacuum. Those compounds which solidify upon concentration are further purified. In some cases, the compounds may be used directly as obtained. In other cases, crystallization is induced by seeding an ether solution with a related compound, and the crystal formed may be further purified.

EXAMPLE I
The following examples illustrate the synthesis of the compounds described herein.

SYNTHESIS OF
3-[5-(1-methoxyethyl)-1,3,4-thiadiazol-2-yl]-4-hydroxy-1-methyl-2-imidazolidinone a Formation of 2-methoxypropanoic acid A two liter flask equipped with a paddle stirrer, thermometer, condenser and nitrogen bubbler was charged with one liter of absolute methanol. Sodium metal (23.0 grams) was slowly added, when all of the metal was dissolved, the solution was cooled and starting at 8C, 190 _ g _ ~5~27~

grams (1.05 mole) of ethyl 2-bromopropionate was added dropwise over a 55-minute period, the final temperature being 2C. The solution was stirred for 45 minutes with ice bath cooling, then 250 milliliters of water and 42 grams of sodium hydroxide pellets were added and the reaction mixture was stirred for an additional 75 minutes, while the temperature rose to 20C.
The reaction mixture was distilled at 90C to remove the methanol, then acidified with 85% phosphoric acid and extracted twice with 200 milliliters of chloroform (CHC13). The extracts were combined and dried over anhydrous magnesium sulfate (MgSO4), filtered and then topped on a roto-vac at 50C to yield 81.1 grams of a colorless l;quid of 2-methoxypropanoic acid.

b. Formation of 5-(1-methoxyethyl)-2-amino-1,3,4-thiadiazole A 150 milliliter, 3-neck flask fitted with a Claisen adaptor, paddle stirrer, thermometer, addition funnel and condenser was charged with 10.5 grams (0.10 mole) of 2-methoxypropanoic acid, prepared above, (9.1 grams, 0.10 mole) of thiosemicarbazide and 50 milliliters of dioxane.
The slurry was heated to 90C and the addition funnel was charged with phosphorous oxychloride (POC13). The POC13 (16.9 grams, 0.11 mole) was slowly added (for 23 minutes) while maintaining the temperature within 85-95C.
The resulting mixture was refluxed for 60 minutes and topped with a water -aspirator to yield a gooey residue. Seventy-five (75) milliliters of water was added and 50% solution of NaOH was also added until the pH of the solution was 10; an aqeuous phase formed. The mixture was placed in a continuous diethylether extractor and extracted for 150 minutes.
The diethylether extract was dried over anhydrous magnesium -sulfate (MgSO4), filtered and some white crystals formed. The extract was topped on a roto-vac at 70C to yield 7.0 grams of a white solid.

~15~)27~

The extractor was recharged with diethylether and after a 16 hour extrac-tion, the diethylether solution was topped on a roto-vac to yield another 6.3 grams of a white solid. The white solids were combined and recrystal-lized from ethanol/chloroform to yield 8.6 grams of pale yellow crystals of

5-(1-methoxyethyl)-2-amino-1,3,4-thiadiazole. (Melting point 155 - 159C).

c. Formation of 5-[1-methoxyethyl]-1,3,4-thiadiazol-2-yl isocyanate dimer A 500 milliliter, 3-neck flask equipped with a magnetic stirrer, thermometer, dry ice condenser/drying tube and inlet from a phosgene (COC12) tank via a calibrated rotameter was charged with 100 mill;liters of ethylacetate saturated with phosgene at 20C (approximately 1.0 mole of phosgene). An additional 100 milliliters of ethylacetate was added;
(7.9 grams of 5-(1-methoxyethyl)-2-amino-1,3,4-thiadiazole (prepared above) was added at a temperature from 0C to room temperature and a gooey oil formed. The resulting mixture was stirred for 17 hours and then the flask was purged with argon until no COC12 was detected. The solution was filtered through a Whatman #42 filter paper to yield a yellow cloudy solution which was topped 70C on a roto-vac to form 8.4 grams of a yellow viscous oil of 5-(1-methoxyethyl)-1,3,4-thiadiazol-2-yl isocyanate dimer.

d. Formation of 3-[5-(1-methoxyethyl)-1,3,4-thiadiazol-2-yl]-1-methyl-1-(2,2-dimethoxyethyl)urea At ambient temperatures, 5.4 grams (0.045 mole) of methylamino-acetaldehyde dimethylacetal was slowly added to a 50 milliliter benzene solution containing 5.4 grams (0.045 mole) of the 5-(1-methoxyethyl)-1,3,4-thiadiazol-2-yl isocyanate dimer (prepared above). The resulting solution was refluxed for 20 minutes; hexane was added resulting in the formation of an oil, the mixture was topped on a roto-vac at 70C to 13.2 3 ~5~Z71 grams of a hazy viscous oil which was dissolved in diethylether, and filtered. The diethylether solution was topped on a roto-vac at 70C to yield 12.9 grams of a red oil of 3-[5-(1-methoxyethyl)-1,3,4-thiadiazol-2-yl]-1-methyl-1-(2,2-dimethoxyethyl)urea.

e. Synthesis of 3-[5-(1-methoxyethyl)-1,3,4-thiadiazol-2-yl]-1-methyl-4-hydroxy-2-imidazolidinone A solution containing 5.4 grams of the 3-[5-(1-methoxyethyl)-1,3,4-thiadiazol-2-yl]-1-methyl-(2,2-dimethoxyethyl)urea (prepared above) in 150 milliliters of water and 1.5 milliliters of concentrated hydro-chloric acid (HCl) was refluxed for 20 minutes, and the aqueous phase wasextracted three times with 50 milliliters of chloroform (CHC13). The 150 milliliter chloroform extract was dried over anhydrous MgS04, filtered and topped on a roto-vac at 70C to yield 2.9 grams of a yellow viscous oil of 3-[5-(1-methoxyethyl)-1,3,4-thiadiazol-2-yl]-1-methyl-4-hydroxy-2-imidazolidinone.
IR spectra: C = 0 band at 1720 cm~l broad N-H band at 3300 ~lcm NMR: (CDCL3) 6.62~ (br. singlet,lH), 6.17~ (mult., lH), 4.69~ (quartet, lH), 3.90~ (mult., 5H), 3.50~ (mult., 5H), 3.32~ (sing., 5H), 2.91~ (singlet, 3H), 1.53~ (doublet, 3H).
A second preparation of the above compound gave a crude oily product which produced crystals from ether/chloroform/hexane, m.p. 85-91C.

EXAMPLE II

3-[5-[1-(1-methylethoxy)ethyl]-1,3,4-thiadiazol-2-yl]-4-hydroxy-l-methyl-2--midazolidinone a. Formation of 2-(1-methylethoxy)propanoic acid A 500 milliliter, 3-neck flask equipped with a magnetic stirrer, thermometer, addition funnel, condenser and nitrogen bubbler was charged 3~15~Z71 with 250 milliliters of dry isopropyl alcohol. Sodium metal (7.1 grams, 0.31 mole) in small pieces was added and the solution was heated to reflux to compLete the reaction~ After cooling to 60C, 54.3 grams (0.30 mole) of ethyl 2-bromopropionate in 50 milliliters of isopropanol was added dropwise over a 20 minute period, and then the solution was refluxed for 2 hours, and left standing overllight. One hundred fifty (150) milliliters of water and 13.0 grams of sodium hydroxide pellets were added and then the mixture was distilled at 90C, then cooled in an ice bath and acidified to pH2 with concentrated hydrochloric acid. The oil phase which formed was extracted with 150 milliliters of dichloromethane, CH2C12, and - -the extract was dried over anhydrous magnesium sulfate, filtered and topped on a roto-vac at 70C to yield 27.8 grams of a pale yellow viscous liquid of 2-(1-methylethoxy)propanoic acid.

b. Formation of 5-[1-(1-methylethoxy)ethyl]-2-amino-1,3,4-thiadiazole A 150 milliliter, 3-neck flask equipped with a Claisen adaptor, paddle stirrer, thermometer, addition funnel and condenser was charged with 7.9 grams (0.060 mole) of 2-(1-methylethoxy)propanoic acid, (prepared above (5.5 grams, 0.060 mole) of thiosemicarbazide and 50 milliliters of dioxane. The slurry was heated to 95C and the addition funnel was charged with phosphorous oxychloride (POC13). The POC13 (lO.l grams, 0.066 mole) was slowly added (for 17 minutes) while maintaining the temperature within 85-95C. The reaction mixture was refluxed for 24 minutes, topped with a water aspirator to remove volatiles (HCl, POC13 and some dioxane), leaving a residue to which 50 milliliters of water was added and a 50%
solution of NaOH until the pH of the solution was lO. A two phase system formed, which was charged .nto a continuous diethylether extractor and extracted for 17 hours. The diethylether extract was topped on a roto-vac ~15~2~1 at 70 C to yield 10.2 grams of white crystals which were recrystallized from the minimum amount of carbontetrachloride/ethanol solution to yieid white platelets. They were filtered off and air dried to yield 8.1 grams of white platelets of 5-[1-(1-methylethoxy)ethyl]-2-amino-1,3,4-thiadiazole, (melting point 120-145C).

c. Formation of 5-[1-(1-methylethoxy)ethyl]-1,3-4-thiadiazol-Z-yl isocyanate dimer A 200 milliliter, 3-neck flask equipped with a magnetic stirrer, thermometer, dry ice condenser/drying tube and inlet from a phosgene (COC12) tank via a calibrated rotometer was charged with 50 milliliters of ethyl acetate which was saturated with phosgene at 20C (approximately 0.5 moles of phosgene). An additional 100 milliliters of ethyl acetate was added; (8.1 grams) of 5-[1-(l-methylethoxy)ethyl]-2-amino-1,3,4-thiadiazole, (prepared above) was added at 0C. The resulting solution was stirred overnight at room temperature, and the flask was purged with argon until no COC12 was detected. The cloudy solution was filtered through a Whatman #42 filter paper to yield a solution which contained 5-[1-(1-methylethoxy)ethyl]-1,3,4-thiadiazol-2-yl isocyanate dimer.

d. Formation of 3-[5-[1-(1-methylethoxy)ethyl]-1,3-4-thiadiazol-2-yl]-1-methyl-1-(2,2-dimethoxyethyl)urea Methylaminoacetaldehyde dimethylacetal (5.6 grams, 0.047 mole) was added dropwise to the 150 milliliter ethyl acetate solution containing (0.047 mole) of the 5-[1-(1-methylethoxy)ethyl]-1,3,4-thiadiazol-2-yl isocyanate dimer (prepared above) and the resulting solution was heated to reflux, cooled and hexane was added and the resulting solution was placed in a refrigerator and topped on a roto-vac at 70C to yield 14.0 grams of an orange oil of 3-[5-[l-(1-methylethoxy)ethyl]-1,3,4-thiadiazol-2-yl]-l-methyl-1-(2,2-dimethoxyethyl)urea.

~15~Z7~

e. Synthesis of 3-[5-[1-(l~nethylethoxy)ethyl]-1,3,4-thiadiazol-2-yll-1-methyl-4-hydroxy-2-imidazolidinone . _ _ A mixture containing 4.2 ~rams of the 3-[5-[1-(2-methylethoxy) ethyl]-1,3,4-th;adiazol-2-yl]-1-methyl-(2,2-dimethoxyethyl)urea (prepared above), 150 milliliters of water and 1.5 milliliters of concentrated hydrochloric acid (HCl) was refluxed for 15 minutes, then cooled and extracted twice with 50 milliliters of chloroform. The chloroform solution was dried over anhydrous magnesium sulfate (MgS04), filtered, and topped on a roto-vac at 70C to yield 3.5 grams of a yellow oil which was dissolved in diethylether and seeded with crystals of Example Ie. and allowed to crystallize overnight. White crystals formed which were removed by suction filter and then dried in a vacuum oven at 80C to yield 1.6 grams of white crystals of 3-[5-[1-(1-methylethoxy)ethyl]-1,3,4-thiadiazol-2-yl]-1-methyl-4-hydroxy-2-imidazolidinone. (Melting point 106-109C).

INTERMEDIATE COMPOVNDS
Although the other compounds described herein and represented graphically by Formulas III and IV possess no herbicidal properties and compounds of Formula V possess herbicidal properties, nevertheless, the compounds represented by the Formulas III, IV and V are very useful because they are intermediates for the synthesis of the novel compounds represented by Formula I.

APPLICATIONS OF THE COMPOSITIONS AGAINST WEEDS
. . _ _ The novel compounds of Formula I are particularly valuable for weed control because they are toxic to many species and groups of weeds and are relatively nontoxic to many beneficial plants. The exact amount of one 1~5VZ71 or more of the compounds required depends upon a variety of Eactors, including the hardiness of the particular weed species, the weat'ner, the type of soil, the method of application, the kind of beneficial plants in the same area, and the like. Thus, while the application of up to only about one or two ounces of active compound per acre may be sufficient for good control of a light infestation of weeds growing under adverse condi-tions, the application of 2 pounds or lO pounds or more of an active compound of Formula I per acre may be required for good control of a dense infestation of hardy perennial weeds growing under favorable conditions.
a. Examples Of Weeds Which May Be Controlled By The Compounds Described Herein _ _ .
Weeds are undesirable plants growing where they are not wanted, having no economic value, and interfering with the production of cultivated crops, with the growing of ornamental plants, or with the welfare of livestock. Weeds may be classified as broadleaf or grassy weeds, a classification which includes many types of known weeds. It is believed that the compositions set forth herein, when applied in a herbicidally effective amount may control field pennycress, ryegrass, goosegrass, chickweed, purslane, smartweed, knotweed, wild buckwheat, kochia, medic, corn cockle, ragweed, sow-thistle, croton, cuphia, dodder, fumitory, groundsel, hempnettle, knawel, spurge, spurry emex, jungle rice, pondweed, dogfennel, carpetweed, bedstraw, ducksalad, naiad, chestgrass, fall panicum, witchgrass, switchgrass, watergrass, teaweed, wild turnip and sprangletop;
biennials such as wild carrot, matricaria, wild barley, campion, chamomile, burdock, mullein, roundleaved mallow, bull thistle, houndstongue, moth mullein, and purple star thistle; or perennials such as white cockle, perennial ryegrass, quackgrass, Canada thistle, bindweed, Bermuda grass, sheep sorrel, curly dock, nutgrass, field chickweed, dandelion, campanula, 1~5S~27:~

field bindweed, Russian knapweed, mesquite, toadflax, yarrow, aster, gromwell, horsetail, ironweed, sesbania bulrush, cat-tail, winter-cress, horsenettle, nutsedge, milkweed and sicklepod.
However, the important weeds of the genera gainst which most of the compounds of the invention, particuLarly the preferred compounds described herein, are most effective preemergence and/or postemergence at 10 pounds per acre are: Sida, Datura, Brassica, Sorghum, Sesbania, Ipomoea, Avena, and Echinochola. Weed species against which the compounds of the invention are most effective (postemergence) are: Sida spinosa (L) (teaweed), Datura stramonium (jimsonweed), Brassica kaber (wild mustard), Sorghum halepense (johnsongrass), Sesbania spp. (coffeeweed), Ipomoea purpurea (L) Roth (tall morningglory), Avena fatua (wild oats) and Echinochola crusgalli (barnyardgrass).
The most preferred compounds, wherein R and R' are methyl, and X is oxygen is very effective against the above mentioned genera, and species of weeds, as well as being safe to use on crops, when applied postemergence or preemergence at rates of up to two or three pounds per acre.
b. Description Of The Method of Controlling Weeds As used herein and in the Claims, the method of controlling the weeds comprises contacting the weeds with a herbicidally effective amount of a compound represented by the graphic formula described herein. The term "contacting the weeds" refers to any method of contacting the weeds, both preemergence (before the weeds appear) and/or postemergence (after the weeds appear), such as applying granules of the compound to the soil prior to emergence, or spraying a solution of the compound or compounds described by the general formula, or any other method known in the art by ~.~5~271 which the weeds are contacted either before they emerge or after they emerge, or both before and after they emerge, with one or more of the compounds represented by the general Formula I described herein. The phrase "herbicidally effective amount" refers to that amount required under the environmental conditions in order to effectively control, that is, by -~
which the weeds are injured so as not to be able to recover from the application of the compound, or to be killed by the compound.
c. General Application Of The Compounds For practical use as herbicides, the compounds of this invention are generally incorporated into herbicidal formulations which comprise an inert carrier and a herbicidally toxic amount of a compound mentioned herein. Such herbicidal formulations enable the active compound to be applied conveniently to the site of the weed infestation in any desired quantity. These formulations can be solids such as dusts, granules or wettable powders or they can be liquids such as solutions, aerosols or emulsifiable concentrates.
For example, dusts can be prepared by grinding and blending the active compound with a solid inert carrier such as the talcs, clays, silicas, prophyllite, and the like. Granular formulations can be prepared by impregnating the compound, usually dissolved in a suitable solvent, onto and into granulated carriers such as the attapulgites or the vermiculites, usually of a particle size range of from about 0.3 to 1.5 millimeters.
Wettable powders, which can be dispersed in water or oil to any desired concentration of the active compound, can be prepared by incorporating wetting agents into concentrated dust composition.
In some cases the active compounds are sufficiently soluble in common organic solvents such as kerosene or xylene so that they can be ~5QZ7~

used directly as solutions in these solvents. Frequently, solutions of herbicides can be dispersed under superatmospheric pressure as aerosols.
However, preferred liquid herbicidal formulations are emulsifiable concen-trates, which comprise an active compound according to this invention and as the inert carrier, a solvent and an emulsifier. Such emulsifiable concentrates can be extended with water and/or oil to any desired concen-tration of active compound for application as sprays to the site of the weed infestation. The emulsifiers most commonly used in these concentrates are nonionic or mixtures of nonionic with anionic surface-active agents.
With the use of some emulsifier systems, an inverted emulsion (water in oil) can be prepared for direct application to weed infestations.
A typical herbicidal formulation according to this invention is illustrated by the following example, in which the quantities are in parts by weight.

EXAMPLE III
PREPARTION OF A DUST
Product of Example I 10 Powdered Talc 90 The above ingredients are mixed in a mechanical grinder-blender and are ground until a homogeneous, freeflowing dust of the desired par-ticle size is obtained. This dust is suitable for direct application to the site of the weed infestation.
d. Mixtures Of Compounds Alone Or In Mixtures Although all of the compounds described herein and represented by the general formula described herein are useful as herbicides, some of these are preferred and are better for applications against weeds. In ~5~271 general, all of the compounds described herein may be used either alone or together in mixtures. When used in mixtures, the amount of ratio of one compound to another may vary from 0.01 to 100.
e. Manner Of Applica~ion Of The Compounds Of This Invention _ -The compounds of this invention can be applied as herbicides in any manner recognized by the art. One method for the control of weeds comprises contacting the locus of said weeds with a herbicidal formulation comprised of an inert carrier and one or more of the compounds of this invention as an essential active ingredient, in a quantity which is - -herbicidally toxic to said weeds. The concentration of the new compounds of this invention in the herbicidal formulations will vary greatly with the type of formulations will comprise from about 0.05 to about 95% by weight of the active compounds of this invention. In a preferred embodiment of ; this invention, the herbicidal formulations can also comprise other pesticides, such as insecticides, nematocides, fungicides, and the like;
; stabilizers, spreaders, deactivators, adhesives, stickers, fertilizers, activators, synergists, and the like.
The compounds of the present invention are also useful when combined with other herbicides and/or defoliants, desiccants, growth inhibitors, and the like in the herbicidal formulations heretofore described.
These other materials can comprise Erom about 5% to about 95~ of the active ingredients in the herbicidal compositions. Use of combinations of the present invention provide herbicidal formulations which are more effective in controlling weeds and often provide results unattainable with separate formulations of the individual herbicides.
f. Examples Of Other Pesticides And Herbicides For Combinations The other herbicides, defoliants, desiccants, and plant growth inhibitors, with which the compounds of this invention can be used in the ~ ~54~Z~

herbicidal formulations to control weeds, can include: chlorophenoxy herbicides such as 2,4-D, 2,4,5-T, MCPA, MCPB, 4-(2,4-DB), 2,4-DEB, 4-CPB, 4-CPA, 5-CPP, 2,4,5-TES, 3,4-DA, silvex and the like; carbamate herbicides such as IPC, CIPC, swep, barban, BCPC, CEPC, CPPC, and the like; thiocar-bamate and dithiocarbamate herbicides such as CDEC, metam sodium, EPTC, diallate, PEBC, perbulate, vernolate and the like; substituted urea herbicides such as norea, siduron, dichloroal urea, chloroxuron, cycluron, fenuron, monuron, monuron TCA, diuron, linuron, monolinuron, neburon, buturon, trimeturon, and the like; symmetrical triazine herbicides such as simazine, chlorazine, desmetryne, norazine, ipazine, prometryn, atrazine, -trietazine, simetone, prometone, propazine, ametryne, and the like;
chloroacetamide herbicides such as alpha-chloro-N,N-dimethylacetamide, CDEA, CDAA, alpha-chloro-N-isopropylacetamide, 2-chloro-N-isopropyl-acetanilide, 4-(chloroacetyl)morpholine, l-(chloroacetyl)piperidine, and the like; chlorinated aliphatic acid herbicides such as TCA, dalapon, 2,3-dichloropropionic acid, 2,2,3-TPA, and the like; chlorinated benozic acid and phenylacetic acid herbicides such as 2,3,6-TBA, 2,3,5,6-TBA, dicamba, tricamba, amiben, fenac, PBA, 2-methoxy-3,6-dichlorophenylacetic acid, 3-methoxy-2,6-dichlorophenylacetic acid, 2-methoxy-3,5,6-trichloro phenylacetic acid, 2,5-dichloro-3-nitrobenzoic ac;d, dual, metribuzin and the like; and such compounds as aminotriazole, maleic hydrazide, phenyl mercuric acetate, endothall, biuret, technical chlordane, dimethyl 2,3,5,6-tetrachloroterephthalate, diquat, erbon, DNC, DNBP, dichlobenil, DPA, diphenamid, dipropalin, trifluralin, solan, dicryl, merphos, DMPA, DSMA, MSMA, potassium azide, acrolein, benefin, bensulfide, A~S, bromacil, 2-(3,4-dichlorophenyl)-4-methyl-1,2,4-oxadiazolidine-3,5-dione, bromoxynil, cacodylic acid, CMA, CPMF, cypromid, DCB, DCPA, dichlone, diphenatril, DT, ~lS~Z71 DNAP, EXD, ioxynil, isocil, potassium cyanate, MAA, MAMA, MCPES, MCPP, MH, molinate, NPA, paraquat, PCP, picloram, DPA, PCA, phrichlor, sesone, terbacil, terbutol, TCBA, LASS0, planavin, sodium tetraborate, calcium cyanamide, DEF, ethyl xanthogen disulfide, sindone, sindone B, propanil and the like. Such herbicides can also be used with the compositions of this invention in the form of their salts, esters, amides and other derivatives whenever applicable to the particular parent compounds.
g. Examples Of Herbicidal Control The following examples illustrate the utility of the compositions described herein for the control of weeds. ~
These tests described herein were conducted in a laboratory under laboratory conditions, using standard laboratory procedures.

EXAMPLE IV
When the compound of 3-[5-(1-methoxy)ethyl)-1,3,4-thiadiazol-2-yl]-4-hydroxy-1-methyl-2-imidazolidinone (Example I) was applied post-emergence at two pounds per acre to the weed species: Sida spinosa (teaweed), Sesbania spp. (coffeeweed), Echinochola crusgalli (L) (barnyard-grass), Gossypium hirsutum (L) (cotton), Avena fatua (L) (wild oats), Datura stramonium (L) (jimsonweed), Sorghum halepense (L) (johnsongrass), Ipomoea purpura (L) Roth (morningglory, tall), Seta ia glauca (L) (yellow -~
foxtail), and Brassica kaber (L) (wild mustard), at the end of twenty-one (21) days, many of the weeds were so severely injured that they could not recover, and others were killedO

EXAMPLE V
When the compound 3-[5-[2-(1-methoxymethyl)ethyl]-1,3,4-thi-adiazol-2-yl]-4-hydroxy-1-methyl-2-imidazolidinone was prepared in a 11~27.1 manner similar to that of the compound of Example I, was applied to the same weed species under the same conditions as in Example IV, all of the weed species were gro~ing.
While the invention has been described with reference to the specific details of certain illustrative embodiments, it is not intended that it shall be limited thereby except insofar as such details appear in the accompanying claims.

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A compound of general Formula I:

(I) wherein:
X is oxygen or sulfur, R is an alkyl of up to four carbon atoms, an alkenyl of up to three carbon atoms, an alkynyl of up to three carbon atoms, or a haloalkyl selected from the group consisting of chloromethyl, bromomethyl, 2-chloro-ethyl, and 2-bromoethyl, and R' is an alkyl of up to four carbon atoms.

2. The compound as recited in Claim 1 wherein X is sulfur.

3. The compound as recited in Claim 2 wherein R' is an alkyl of up to four carbon atoms.

4. The compound as recited in Claim 3 wherein R is a haloalkyl selected from the group consisting of chloromethyl, bromomethyl, 2-chloroethyl, and 2-bromoethyl.

5. The compound as recited in Claim 3 wherein R is an alkynyl of up to three carbon atoms.

6. The compound as recited in Claim 3 wherein R is an alkenyl of up to three carbon atoms.

7. The compound as recited in Claim 3 wherein R is an alkyl of up to four carbon atoms.

8. The compound as recited in Claim 2 wherein R' is methyl.

9. The compound as recited in claim 8 wherein R is a haloalkyl selected from the group consisting of chloromethyl, bromomethyl, 2-chloroethyl, and 2-bromoethyl.

10. The compound as recited in Claim 8 wherein R is an alkynyl of up to three carbon atoms.

11. The compound as recited in Claim 8 wherein R is an alkenyl of up to three carbon atoms.

12. The compound as recited in Claim 8 wherein R is an alkyl of up to four carbon atoms.

13. The compound as recited in Claim 8 wherein R is methyl.

14. The compound as recited in Claim 1 wherein X is oxygen.

15. The compound as recited in Claim 14 wherein R' is an alkyl of up to four carbon atoms.

16. The compound as recited in Claim 15 wherein R is a haloalkyl selected from the group consisting of chloromethyl, bromomethyl, 2-chloroethyl, and 2-bromoethyl.

17. The compound as recited in Claim 15 wherein R is an alkynyl of up to three carbon atoms.

18. The compound as recited in Claim 15 wherein R is an alkenyl of up to three carbon atoms.

19. The compound as recited in Claim 15 wherein R is an alkyl of up to four carbon atoms.

20. The compound as recited in Claim 14 wherein R' is methyl.

21. The compound as recited in Claim 20 wherein R is a haloalkyl selected from the group consisting of chloromethyl, bromomethyl, 2-chloroethyl and 2-bromoethyl.

22. The compound as recited in Claim 20 wherein R is an alkynyl of up to three carbon atoms.

23. The compound as recited in Claim 20 wherein R is an alkenyl of up to three carbon atoms.

24. The compound as recited in Claim 20 wherein R is an alkyl of up to four carbon atoms.

25. The compound as recited in Claim 1 which is 3-[5-(1-methoxyethyl)-1,3,4-thiadiazol-2-yl]-4-hydroxy-1-methyl-2-imidiozolidionone.

26. A method of controlling weeds, which comprises contacting the weeds with a herbicidally effective amount of a compound of Formula I:

(I) wherein:
X is oxygen or sulfur.

R is an alkyl of up to four carbon atoms, an alkynyl of up to three carbon atoms, an alkenyl of up to three carbon atoms, or a haloalkyl selected from the group consisting of chloromethyl, bromomethyl, 2-chloroethyl and 2-bromoethyl, R' is an alkyl of up to four carbon atoms.

27. The method as recited in Claim 26 wherein X is sulfur.

28. The method as recited in Claim 27 wherein R' is an alkyl of up to four carbon atoms.

29. The method as recited in Claim 28 wherein R is methyl.

30. The method as recited in Claim 27 wherein R' is methyl.

31. The method as recited in Claim 30 wherein R is methyl.

32. The method as recited in Claim 26 wherein X is oxygen.

33. The method as recited in Claim 32 wherein R' is an alkyl of up to four carbon atoms.

34. The method as recited in Claim 33 wherein R is methyl.

35. The method as recited in Claim 32 wherein R' is methyl.

36. The method as recited in Claim 35 wherein R is a haloalkyl selected from the group consisting of chloromethyl, bromomethyl, 2-chloroethyl, and 2-bromoethyl.

37. The method as recited in Claim 35 wherein R is an alkynyl of up to three carbon atoms.

38. The method as recited in Claim 35 wherein R is an alkenyl of up to three carbon atoms.

39. The method as recited in Claim 35 wherein R is an alkyl of up to four carbon atoms.

40. The method as recited in Claim 35 wherein R is an alkyl selected from the group consisting of methyl, ethyl and isopropyl,

41. The method as recited in Claim 35 wherein R is methyl.

42. The method as recited in Claim 26 wherein the weeds are contacted preemergence.

43. The method as recited in Claim 42 wherein the weeds are located among a growing crop.

44. A method of controlling weeds of the species Sida spinosa (teaweed), Sesbania spp. (coffeeweed), Echinochola crusgalli (barnyardgrass), Avena fatua (wild oats), Datura Stramonium (jimsonweed), Sorghum halepense (johnsongrass), Ipomoea purpura (morningglory), Setaria glauca (yellow foxtail), and Brassica kaber (wild mustard) located among a growing crop which comprises contacting the weeds preemergence with a herbicidally effective amount of 3-[5-[1-(1-methylethoxy)ethyl]-1,3,4-thiadiazol-2-yl]-4-hydroxy-1-methy1-2-imidazolidinone.

45. A method for making a compound of Formula I:

(I) wherein:
X is oxygen or sulfur, R is an alkyl of up to four carbon atoms, an alkenyl of up to three carbon atoms, an alkynyl of up to three carbon stoms, or a haloalkyl selected from the group consisting of chloromethyl, bromomethyl, 2-chloroethyl, and 2-bromoethyl, and R' is an alkyl of up to four carbon atoms, which process comprises the steps of refluxing an acidic reaction nedium of a compound of Formula V:

(V) wherein:
R is as defined, until a compound of Formula I forms, and separating out the compound of Formula I from the solution.

46. The method as recited in Claim 45 wherein the process of forming a compound of Formula I further comprises the steps of reacting a compound of Formula IV where R is as defined, (IV) with methylaminoacetaldehyde dimethylacetal until a compound of Formula V forms, and separating out the compound of Formula V from the reacting medium.

47. The method as recited in Claim 46 wherein the process of forming a compound of Formula I further comprises the steps of reacting a compound graphically represented by Formula III where R is as defined, with phosgene (COCl2) in a solvent capable of dissolving the phosgene and the compound of Formula III, until a compound of Formula IV forms, and separating the compound of Formula IV from the reaction medium.

(III)

48. The method as recited in Claim 47 wherein the solvent is ethyl acetate.

49. The method as recited in Claim 45 wherein R' is methyl.

50. The method as recited in Claim 49 wherein R is an alkynyl of up to three carbon atoms.

51. The method as recited in Claim 49 wherein R is an alkenyl of up to three carbon atoms.

52. The method as recited in Claim 49 wherein R is a haloalkyl selected from the group consisting of chloromethyl, bromomethyl, 2-chloroethyl, and 2-bromoethyl.

53. The method as recited in Claim 49 wherein R is an alkyl of up to four carbon atoms.

54. The method as recited in Claim 49 wherein R is an alkyl selected from the group consisting of methyl and ethyl.