FR2463138A1 - 3- (5- (1- (ALCOXY OR ALKYLTHIO) -ALKYL, ALKYNYL, ALKENYL OR HALOGENOALKYL) -1,3,4-THIADIAZOL-2-YL) -4-HYDROXY-1-METHYL-2-IMIDAZOLIDINONES AND THEIR APPLICATION TO CONTROL OF WEEDS - Google Patents

Abstract

THE INVENTION CONCERNS 3-5-1- (ALCOXY OR ALKYLTHIO) -ALKYL, ALCYNYL, ALCENYL OR HALOGENOALKYL-1,3,4-THIADIAZOL-2-YL-4-HYDROXY-1-METHYL-2-IMIDAZOLIDINONES. THE PREFERRED COMPOUND IS 3-5- (1-METHOXYETHYL) -1,3,4-THIADIAZOL-2-YL-4-HYDROXY-1-METHYL-2-IMIDAZOLIDINONE. APPLICATION TO THE DESTRUCTION OF WEEDS.

Description

The present invention relates to 1,3,4-thiadiazole

  Substituted 2-yl-4-hydroxy-1-methyl-2-imidazolidinones, and in particular 3- [5- [1- (oxy or alkylthio) -alkyl, alkynyl,

  alkenyl or haloalkyl-1,3,4-thiadiazol-2-yl] -4-hydroxy-.

  1-methyl-2-imidazolidinone. Imidazolidinones, as a class of products,

  are described in patents and in the chemical literature.

  than; however, there is no mention of herbicides

  new ones currently described or their use

  for the control of weeds, which are

here.

  The subject of the invention is compounds corresponding to the formula:

0

H S

R '- X - CH (3)

  where X is an oxygen or sulfur atom,

  R is an alkyl group containing at most 4 carbon atoms

  bone, an alkenyl group containing at most 3 carbon atoms

  bone, an alkynyl group containing at most 3 carbon atoms

  bone or a haloalkyl group which may be a chloro group

  romethyl, bromomethyl, 2-chloroethyl or 2-bromoethyl, and

  R 'is an alkyl group containing at most 4 carbon atoms.

  bone; as well as the intermediates corresponding to the formulas: H R'-2 -c, '(II) R H

R'_NCO (IV)

2 (IV)

R

H S HO 0

  In which: X, R and R 'are as defined above, and also the process for the preparation of the compounds corresponding to the above-mentioned formulas

  the application of these to the fight against

  goes herbs. The compounds of formula I are particularly

  useful for weed control in pre-emergence

  and post-emergence, and are selective for other weeds, both post-emergence and pre-emergence, at small application rates, particularly for the compound in which X is an oxygen atom and R and R 'aeS

  are / methyl groups. For example, 3- [5- (1-methoxyethyl) -

  1,3,4-thiadiazol-2-yl] -4-hydroxy-1-methyl-2-imidazolidinone, wherein X is an oxygen atom and R and R 'are methyl groups, is useful in the control of weeds such as Spinosa Aids, stramony weevils,

  yellow foxtail, parsley, Aleppo sorghum,

  species of Sesbania, velvetleaf, bindweed, wild oats and rooster weed, and

  safe for crops in small doses.

  Examples of compounds falling within the formula I given and explained above are:

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

  4-hydroxy-l-methyl-2-imidazolidinone,

  3- [5- [1-butylthio-2-bromoethyl] -1,3,4-thiadiazol-2-yl];

  4-hydroxy-l1-methyl-2-imidazolidinone,

  3- [5-l-t-butoxy-2-bromoethyl-1,3,4-thiadiazol-2-yl]

  4-hydroxy-l-methyl-2-imidazolidinone,

  3- (5-L1-methoxy-3-chloro-propyl] -1,4,4-thiadiazol-2-yl;

  4-hydroxy-l-methyl-2-imidazolidinone,

  3- [5- 1-ethylthio-3-bromopropyl-1,3,4-thialazol-2-yl] -

  4-hydroxy: -1-methyl-2-imidazolidinone,

  3- [1-ethoxy-2-propynyl] -1,3,4-thiadiazol-2-yl

  4-hydroxy-l-methyl-2-imidazolidinone,

  3- [5- U-isopropylthio-2-butynyl] -1,3,4-thiadiazol-2-yl] -

  4-hydroxy-l1-methyl-2-imidazolidinone,

  3- [5- [-isopropoxy-3-butynyl] -1,3,4-thiadiazol-ayl);

  4-hydroxy-l1-methyl-2-imidazolidinone,

  3- [5- 1-Methoxy-2-propenyl-1,3,4-thiadiazol-2-yl] -

  4-hydroxy-1-methyl-2-imidazolidinone,

  3- [1-methylthio-2-butenyl] -1,3,4-thiadiazol-2-yl;

  4-hydroxy-l-methyl-2-imidazolidinone,

  3-L5-L1-ethoxy-2-chloroethyl-1,3,4-thiadiazol-2-yl

  4-hydroxy-l1-methyl-2-imidazolidinone,

  3- [5-l-ethylthio-2-bromoethyl-1,3,4-thiadiazol-2-yl];

  4-hydroxy-l1-methyl-2-imidazolidinone,

  3-5-El-propoxy-3-chloropropyl-1,3,4-thiadiazol-2-yl] -

  4-hydroxy-1-methyl-2-imidazolidinone,

  3β-1-propylthio-3-bromopropyl-1,3,4-thiadiazol-2-yl;

  4-hydroxy-1-methyl-2-imidazolidinone,

  3-C5-1-isopropoxy-3-butenyl-1,3,4-thiadiazol-2-yl

  4-hydroxy-l-methyl-2-imidazolidinone,

  3- [5- 1-isopropylthio-1-pentenyl] -1,3,4-thiadiazol-2-yl];

  4-hydroxy-1-methyl-2-imidazolidinone,

  3-E5-E-butoxy-1- (3-methylbutyl) -1,3,4-thiadiazol-2-yl -

  4-hydroxy-l-methyl-2-imidazolidinone,

  3- {5-1-butylthio-2- (2-methylbutyl) -1,1,4,4-thiadiazol-2-yl] -

  4-hydroxy-l1-methyl-2-imidazolidinone,

  3- [5- 1-sec-butoxy-1- (2,2-dimethylpropyl) -1,3,4-thiadiazole)

  2-YLJ-4-hydroxy-l-methyl-2-imidazolidinone,

  3- [5- L-sec-butylthio-1-butyl-1,3,4-thiadiazol-2-yl] -

  4shydroxy-1-methyl-2-imidazolidinone,

  3- (5-tert -butoxy- (2-methylpropyl) -3-1,3,4-thiadiazol-2-yl);

  4-hydroxy-1-methyl-2-imidazolidinone, and

  3-L5-EA-t-butylthipropyl-1,3,4-thiadiazol-2-ylf

  4-hydroxy-1-methyl-2-imidazolidinone, All the compounds described herein are useful for the purposes indicated herein, but some compounds are more useful than others. Compounds in which R is an alkynyl group are of general utility, while the compounds

  in which R is an alkenyl group are more effective.

  Compounds in which R is a haloalkyl group

  indicated here are very useful and, among these, the

  preferred are those in which R is a chloro group

  romethyl or bromomethyl. Compounds in which R is

  an alkyl group as indicated herein are especially

  and especially those in which the alkyl group is a methyl, ethyl or isopropyl group. R 'is preferably a methyl group and, in

  Generally, X is preferably an oxygen atom. The components

  following are the most preferred: 3- 5- (1-

  methylthioethyl) -1,3,4-thiadiazol-2-ylg-4-hydroxy-1-methyl-2-

  imidazolidinone and 3- (1-methoxyethyl) -1,3,4-thiadiazole

  2-yl-4-hydroxy-l-methyl-2-imidazolidinone.

  The synthesis of the compound proceeds according to the general reactions 1,2,3,4 and 5 below:

H 0

R 'X ---- M + + Y C OH (1)

R

(VI) (VII)

H S

The

R'-X -CX OH + POC1 + HNCNHNH2 (2)

3 2

R 1. dioxane, reflux 2. NaOH / H2O H

R 'X_ _-

  R coc: ethyl acetate ethyl acetate N N H NCO

CH3N --- CHW-CH (OCH: 5) 2

## STR5 ##

R CH

H3 + OO

N CH3

  k OH (I) NH 2 (3) (III) wherein R (IV) V (4) H

R '_X _

  (5) - Preparation of a 5-substituted-2-amino-1,3,5-thiadiazole

  The appropriate metal salt M is reacted, for example

  salt of sodium, potassium or lithium, the appropriate alkanol or alkanethiol represented by formula VI wherein R 'and X are as defined above

  on a 2-halogenated alkanoic acid (or an ester thereof)

  ci), represented by formula VII wherein R is as defined and Y is a chlorine, bromine, or iodine atom, preferably bromine, as indicated by reaction

  1, to form the alkoxycarboxylic acid or alkylthiocarbo-

  substituted xyl represented by formula I in the formula

  which R, R 'and X meet the definition given above.

  In a 100 cm3 reactor equipped with a thermometer, an effective stirrer, a pressure compensation, an addition funnel and a refrigerant with a drying tube,

  the alkoxycarboxylic acid or alkylthiocarboxy acid is introduced

  the appropriate substitute, corresponding to formula II (in

  0.4 to 0.5 mole), an equimolar amount of thio-

  semicarbazide and 30 cm3 of diQxanne.sec. We put in the enton-

  additionally an excess of about 10% of phosphorus oxychloride

  phore, which is added dropwise so as to maintain a reaction temperature of 85 to 95 C and the reaction

  proceeds as shown in Equation 2. The heat is then heated

  The mixture is refluxed for about 1 hour and then the solvent is volatilized by applying a vacuum, for example with a suction tube.

  water. 50 cm3 of water are added to the residue to obtain an emul-

  then basified with 50% sodium hydroxide solution. In the case where a solid product (represented by formula III in which X and R are as defined) is isolated, the product is isolated by filtration and recrystallized if necessary. In other cases, the mixture is extracted with ether, the ether layer is separated from the heavier layers, dried over magnesium sulfate, filtered and concentrated in vacuo to obtain the crude product.

in the form of viscous oil.

  - Preparation of dimeric isocyanates.

  To a solution of phosgene in ethyl acetate (or other suitable solvent) which was prepared by saturating with phosgene 50 to 100 cm3 of solvent at room temperature and then adding again 50 to 100 cm3 of solvent, 10 g of the appropriate 2-amino-1,3,4-thiadiazole (represented by formula III) are added. The mixture is left stirring overnight at room temperature, as indicated by reaction 3, and purged with nitrogen or argon to remove unreacted phosgene. In cases where a solid is obtained, the product (.presented by filtration) is isolated by filtration.

  graphically by formula IV and which is a dimer of iso-

  substituted 1,3,4-thiadiazole cyanate) and dried. In cases where no solid product is observed, the mixture can be starved under vacuum, to obtain the product under

  form of viscous oil or glass.

- Preparation of acetal-ureas.

  The appropriate isocyanate dimer of formula IV and an equivalent amount of methylaminocetaldehyde dimethyl acetal in a solvent are refluxed for 5 to 15 minutes.

  inert form such as ether, benzene or toluene and the reaction

  The reaction is carried out as indicated in reaction 4, so that

  form the product represented by formula V. Some

  Duits can be separated directly from the solution in crystalline form; some others can be crystallized by adding hexane. The product of formula V can be purified, for example by washing with ether or hexane, or recrystallizing from hexane / benzene, ether / benzene or ether / chloroform / benzene. Formula V products which

  are obtained in the form of oils do not need to be pu

rifiés.

  Preparation of the compounds of formula I. About 3 to 4 g of the appropriate acetal-urea of formula V are added to 150 to 200 ml of water containing 1.5 to 2 ml of concentrated hydrochloric acid. The mixture is vigorously stirred and refluxed and the reaction proceeds as shown in Equation 4. The hydrolysis is monitored by thin layer chromatography (alumina / ethyl acetate) until is

  complete and the product containing a compound of

  In some cases, the product may crystallize direc-

  mixture to cooling. In other cases, the compounds of formula I are extracted with chloroform and

  isolated by removing the solvent under vacuum. We purify

  vantage compounds that solidify during the concentration

  tration. In some cases, the

  compounds as they are obtained. In other cases,

  this crystallization by seeding a solution in the e-

  ther using a related compound and can be purified

new-formed crystals.

  Example 1 The following examples illustrate the synthesis of

compounds presently described.

  -Synthesis of 3- [5- (1-methoxyethyl) -1,3,4-thiadiazol-2-yl-

  4-hydroxy-1l-methyl-2-imidazolidinone-

  a) Formation of 2-methoxypropanoic acid

  In a 2 dm3 flask fitted with a stirring device

  of a thermometer, a condenser and a bubbler to

  nitrogen, 1 dm3 of absolute methanol was introduced. We have

  slowly 23.0 g of sodium when all the metal was

  Under, the solution was cooled and, starting at 8 ° C., 190 g (1.05 mol) of ethylbromopropionate were added dropwise over a period of 55 minutes.

  2 C. The solution was stirred for 45 minutes.

  by cooling in an ice bath, then 250 cc of water and 42 g of sodium hydroxide flakes were added, and the mixture was stirred for an additional 75 minutes, while the temperature was 20 C. distilled the mixture at 90 ° C

  to remove the methanol, and then acidified with phos-

  phoric at 85% and extracted twice with 200 cm3 of

  chloroform (CHCl3). The extracts were then combined,

  dried over anhydrous magnesium sulphate (MgSO 4), filtered and then toasted on a "Roto-Vac" at 50 ° C. to obtain 81.1 g.

  a colorless liquid, which was 2-methoxypropanoic acid.

  b) Formation of 5- (1-methoxyethyl) -2-amino-1,3,4-

  thiadiazole In a 150 cc three-necked flask equipped with a

  Claisen adapter, a finned stirrer, a thermo-

  meter, a dropping funnel and a refrigerant,

. .

2 463138

  10.5 g (0.10 mol) of 2-methoxypropanotec acid are

  prepared as above, 9.1 g (0.10 mol) of thiosemicarbazide and 50 cm of dioxane. The slurry was heated to 90 C and

  introduced phosphorus oxychloride (POC13) into the

  addition funnel. 16.9 g (0.11 mol) of POCl3 were added slowly over a period of 23 minutes while maintaining the

  temperature between 85 and 95 C. The mixture was heated

  flow for 60 minutes and was water pumped to obtain a viscous residue. Water (75 cc) was added, and 50% NaOH solution was added until the pH was

  the solution is 10; an aqueous phase was formed.

  The mixture was placed in a continuous diethyl ether extractor.

  The extract was dried over anhydrous magnesium sulfate for 150 minutes.

  (MgSO4), filtered and white crystals formed.

  The mixture was run on a "Roto-Vac" at 70 ° C to obtain 7.0 g of a white solid. Diethyl ether was again introduced and after 16 hours of extraction, the solution was toasted on a "Roto-Vac" to obtain again 6.3 g of a white solid. The white solids were pooled and recrystallized from ethanol / chloroform to give 8.6 g of pale yellow crystals of 5- (1-methoxyethyl-2-amino-1,3),

  4-thiadiazole (mp 155-159 ° C).

  (c) Formation of the 5- (1-methoxy) isocyanate dimer

  ethyl) -1,3,4-thiadiazol-2-yl In a 500 cc three-necked flask equipped with a magnetic stirrer, a thermometer, a dry ice condenser with a drying tube and a entrance coming from a

  phosgene tank (COC12) through a rotating flowmeter

  100 ml of ethyl acetate saturated with

  phosgene at 20 ° C. (ie about 1.0 mole of phosgene). We added

  in addition, 100 cm3 of ethyl acetate; 7.9 g of - (1-methoxyethyl) -2-amino-1,3,4-thiadiazole (prepared as above) was added between 0 ° C and room temperature and it was

  formed a viscous oil. The mixture was stirred for 17 hours.

  res, then the balloon was purged with argon until

  detects more COC12. the solution was filtered on paper

  Whatman filter n 42 to obtain a cloudy yellow solution; it was topped at 70 ° C on a "Roto-Vac" to form 8.4 g of a viscous oil, which was the - (1-methoxyethyl) -1,3,4-thiadiazole isocyanate dimer 2- yle.

  d) Formation of 3- (-1-methoxyethyl) -1,3,4-thia-

  diazol-2-yl-1-methyl-1- (2,2-dimethoxyethyl) urea At room temperature, 5.4 g (0.045 mole) of methylaminoacetaldehyde dimethyl acetal was slowly added to a 50 cc solution of benzene containing 4 g (0.045 moles)

  5- (1-methoxyethyl) -1,3,4-hiadiazole isocyanate dimer

  2-yl (prepared as above). The solution was refluxed for 20 minutes; hexane was added and an oil was formed; the mixture was toasted on C "Roto-Vac" to obtain 13.2 g of a viscous cloudy oil, dissolved in diethyl ether and filtered. The solution was run on a "Roto-Vac" at 70 ° C to obtain 12.9 g of a red oil, which was 3 - 5 - (1-methoxyethyl) -1,3,4.

  thiadiazol-2-yl-1-methyl-1- (2,2-dimethoxyethyl) urea.

  e) Syntesis of 3- (1-methoxyethyl) -1,3,4-thia-

  diazol-2-yl] -1-methyl-4-hydroxy-2-imidazolidinoin

born.

  A solution was refluxed for 20 minutes.

  containing 5.4 g of 3-E- (1-methoxyethyl) -1,3,4-thia-

  diazol-2-yl-1-methyl- (2,2-dimethoxyethyl) -urea (prepared

  as above) in 150 cm3 of water and 1.5 cm3 of chloroacid

  hydrochloric acid and the phase was extracted three times

  aqueous solution with 50 cm3 of chloroform (CHCl3). We dried the ex

  150 cm3 of anhydrous MgS04, filtered and topped

  on a "Roto-Vac" at 70 ° C to obtain 2.9 g of a

  yeast, which was 3- [5- (1-methoxyethyl-1,3,4-thiadia)

  zol-2-yl-methyl-4-hydroxy-2-imidazolidinone.

  Infrared spectrum: band C = O at 1720 cm1, broad

N-H band at 3300 cm 1.

  NMR (CDCI): 6.62 (broad singlet, 1H), 6.17 (multiply),

  plet, 1H), 4.69 equand, 1H), 3.90 (multiplet, 5H); 3.50 (multiplet, 5H), 3.532 (singlet, 5H), 2.91 (singlet, 3H),

1.55 (doublet, 3H).

  A second preparation of the above compound gave an oily crude product, which crystallized in the mixture

  ether / chloroform / hexane; melting point 85 to 91 C.

Example II

  3- [5- [1- (1-methylethoxy) -ethyl] | -1,3,4-ithiadiazol-2-yl34-

  hydroxy-l-methyl-2-imidazolidinone. a) Formation of 2- (1-methylethoxy) propanol in a 500 cc three-necked flask equipped with a magnetic stirrer, thermometer, addition funnel, coolant and A nitrogen bubbler was charged with 250 ml of dry isopropyl alcohol. 7.1 g (0.31 mole) of sodium metal was added in small pieces

  and the solution was refluxed to complete the reaction.

  After cooling to 60 C, it was added dropwise in

  20 minutes 54.3 g (0.30 mole) of 2-bromopropionic acid.

  ethyl acetate in 50 cm3 of isopropanol, then the solution was refluxed for 2 hours and left to stand overnight. 150 ml of water and 13.0 g of sodium hydroxide flakes were added, followed by stirring at 90 ° C., cooling in an ice bath and acidification to pH 2 with hydrochloric acid. concentrated. The oily phase was extracted

  formed by 150 ml of dichloromethane, CH 2 Cl 2, the

  on anhydrous magnesium sulphate, it is filtered,

  head on a "Roto-Vac" at 70 C and obtained 27.8 g of a

  pale yellow viscous quid, which was 2- (1-methylethoxy) acid

propanoic.

  b) Formation of 5- [1- (1-methylethoxy) ethyl] -2-amino

  1,3,4-thiadiazole. In a 150 cc three-necked flask equipped with a

  Claisen adapter, a finned stirrer, a thermoset

  meter, an addition funnel and a refrigerant,

  7.9 g (0.060 mole) of 2- (1-methylethoxy) -propanoic acid

  (prepared as above), 5.5 g (0.060 mole) of thiosemia

  carbazide and 50 cm3 of dioxane. The slurry was heated to C and phosphorus oxychloride (POCl 3) was introduced.

  in the addition funnel. We added slowly (in the

  17 minutes) 10.1 g (0.066 mole) of POC13 while still

* holding the temperature between 85 and 95 C. The mixture was heated at reflux for 24 minutes, was topped with a water pump to remove volatile matter (HCl, POCl and a little dioxane) and there remained a residue to which 50 cm 3 of water and a 50% solution of NaOH were added until the pH was

  from 10. A two-phase system was formed; we -

  It was introduced into a continuous diethyl ether extractor and extracted for 17 hours. The extract was topped with a "Roto-Vac" at 70 ° C to obtain 10.2 g of white crystals

  that has been recrystallised in the minimum amount of

  carbon tetrachloride / ethanol to obtain

  white stools. They were filtered off and air-dried to obtain 8.1 g of white lamellae of -L- (1-methylethoxy) ethyl-1-amino-1,3,4-thiadiazole (dot).

melting point 120 to 145 ° C).

  c) Formation of the isocyanate dimer of 5, l- (1-methyl)

  ethoxy) -ethyl-1,3,4-thiadiazol-2-yl In a 200 cc three-necked flask equipped with a magnetic stirrer, a thermometer, a dry ice condenser with a drying tube and a an inlet from a phosgene tank (COC12) by a rotary flow meter, was introduced 50 cm3 of ethyl acetate saturated with phosgene at 20 C (ie about 0.5 mole of phosgene). An additional 100 cc of ethyl acetate was added; at 0 C, 8 g of -1- (1-methylethoxy) ethyl] -2-amino-1,3,4-thiadiazole (prepared as above) was added. The solution was stirred overnight at room temperature and the flask was purged with argon.

  until COC12 is no longer detected. We filtered the

  blurry elution on Whatman n 42 filter paper to get

  a solution containing the 5-l- (1-methyl) isocyanate dimer

  thylethoxy) -ethyl-1,3,4-thiadiazol-2-yl.

  (d) Formation of 5α- (1-methylethoxy) -ethyl-1,3,4-

  thiadiazol-2-yl -1-methyl-1- (2,2-dimethoxyethyl) -urea

  5.6 g (0.047 mole) of dihydrate were added dropwise.

  Methyl acetal of methylamino acetaldehyde to the solution of 150

  cm 3 of ethyl acetate containing 0.047 mole of isobutylene dimer

  5-d- (1-methylethoxy) -ethyl-1,3,4-thiadiazol-2- cyanate

  yle (prepared as above), the solution was warmed to

  flow, cooled, added hexane, placed

  solution in a refrigerator and was topped on a roto

  Vac at 70 ° C to obtain 14.0 g of an orange oil which was 3- (1-methylethoxy) -ethyl-1,3,4-thiadiazol-2-yl-1-methyl-1- (2 , 2diméthoxyéthyl) urea.

  e) Synthesis of 3- [5- (1-methylethoxy) -ethyl]

  1, 3, 3-thiadiazol-2-ylA -1-methyl-4-hydroxy-2-imidazolidinone A mixture was refluxed for 15 minutes.

  containing 4.2 g of 3-L5-i- (2-methylethoxy) ethyl3 -1,3,4-

  thiadiazol-2-yl -1-methyl- (2,2-dimethoxyethyl) -urea (prepared

  as above) 150 cm3 of water and 1.5 cm3 of hydrochloric acid

  concentrated, then cooled and extracted twice with 50 cm3 of chloroform. The solution was dried over anhydrous magnesium sulphate, filtered, and roto-vacated at 700 ° C to give 3.5 g of a yellow oil, dissolved therein. diethyl ether, inoculated

  with crystals of Example Ie) and allowed to crystallize

  be one night. White crystals were formed, separated by water jet filtration, and dried in a vacuum oven at 80 ° C to obtain 1.6 g of white crystals.

  3- [5-> 1- (1-methyl-ethoxy) -thyl -1,3,4-thiadiazol-2-yl -1.-

  methyl-4-hydroxy-2-imidazolidinone (melting point 106 to

109 C).

Intermediate compounds

  The other compounds presently described and represent

  formulas III and IV have no herbicidal properties.

  While the compounds of formula V have them, however, the compounds of formulas III, IV and V are very useful because they are intermediates for the synthesis of novel compounds of formula I.

  o0 - Applications of weed compositions.

  The novel compounds of formula I are particularly

  useful for weed control because they are toxic to many species and

  weeds and relatively non-toxic to many

  many useful plants. The exact amount of one or

  many of the compounds depend on a variety of factors,

  the resistance of the particular weed species, the time, the type of soil, the mode of application, the nature of the useful plants in the same area, etc. Thus, while it may be sufficient to apply only 70 to 140 g of active compound per hectare to obtain good control of a slight infestation by grasses growing under adverse conditions, it may be necessary to apply 2.24 or 11.2 kg / ha or more to obtain good control of a dense infestation of perennial weeds,

  resistant, growing under favorable conditions.

  a) Examples of weeds that can be controlled by

  the compounds described herein.

  Weeds are unwanted plants that grow where they are not needed, have no economic value, and hinder crop production, ornamental development, or the welfare of livestock. They can be classified as broadleaf weeds or grass / classifaction which includes many types of

  known weeds. It seems that the compositions

  described, applied in an effective quantity, may be able to control the stinkweed, ryegrass,

  the turmeric, the purslane, the pepper of water, the

  knotted birds, wild buckwheat, kochia, alfalfa, githago agrostemma, ragweed, perennoon sowweed, croton, cuphaea, dodder, fumitory, groundsel,

  galactopsis, annual scaler, euphorbia, spermatozoa

  gule, Echnichloa colona, pondweed, stinky chamomile, whorled mollugo, cleavers, ducksalad, nalas, chestgrass, fall panic, quackgrass, switchgrass, aquatic catabrosa, spinosa aida , kohlrabi and leptochloa dubia; biannual weeds such as wild carrot, feverfew, barley, lychnis, chamomile, minor burdock, mullein

  the neglected mallow, the common thistle, the official cynoglossus

  nal, the blattene mullein and the close jay; or bad

  perennial herbs such as white lychnis, perennial ryegrass,

  creeping gropyron, Canada thistle, hedge bindweed, Bermuda grass, sheep sorrel, frizzy rumex,

  round nutmeg, caraists of field, dandelion, camel

  peatweed, field bindweed, Russian knapweed, hemp

  that the woolly, the linear, the yarrow, the aster,

  the gremilus officinale, the horsetail, the verbena hastée, the mas-

  sette, the typha, the common barbarate, the carolina nightshade, the round nutmeg, the common milkweed and the Arabis canadensis.

  However, the most important kinds of weeds against which most of the compounds of the invention,

  particularly the preferred compounds described present-

  are the most effective in pre-emergence and / or post-emergence at 11.2 kg / ha are the genera AIDS, Datura, Brassica, Sorthum, Sesbania, Ipomoea, Avena and Echinochloa. The species

  against which the compounds of the invention are most effectively

  Ficaceae (post-emergence) are: Sida spinosa (L), Datura stramonium (dature stramony), Brassica kaber (wild mustard), Sorghum halepense (Aleppo sorghum), different species of Sesbania, Ipomoea purpurea (L), Roth (large lise: ron), Avena fatua (wild oats) and Echinochloa crusgalli

(panic foot of cock).

  Especially preferred compounds, wherein R and R 'are methyl groups and X is oxygen, are highly effective against the above genera and species, while being safe for use on post-harvest cultures. raised or pre-emergence at doses up to

3.36 kg / ha.

  b) Description of the weed control method

  The weed control method we are discussing here is to put weeds

  contact with an effective amount of a compound according to the

  mule given above. We call Omise in touch "any fashion

  contacting the weeds, as well as in

  in post-emergence, for example by applying granules of the compound to the soil before emergence, or by spraying a solution of the compound or compounds of the general formula, as well as any other method for which the

  weeds before or after emergence, or before

  near it, with one or more of the compounds of the general formula I. The "effective dose" is the dose required,

  under the conditions of the environment, to effectively control

246-3138

  weed, that is, damage to the

  point that they can not recover after the

  or killed by the compound.

  c) General Application of the Compounds For practical use as herbicides, the compounds of the invention are generally incorporated into herbicidal compositions comprising an inert carrier, as well as a compound

  according to the invention in a toxic amount for the bad herbs.

  bes. Such compositions make it possible to apply

  the active compound at the place of infestation, in any desired quantity. These compositions can be solids, such as

  dusting powders, granules or wettable powders

  lables or liquids, such as solutions,

  rosols or emulsifiable concentrates.

  For example, to prepare dusting powders, the active compound can be milled and mixed with a solid inert carrier such as tales, clays, silicas,

  pyrophyllite, etc. To prepare granular compositions, -

  the compound, usually dissolved in a suitable solvent, can be impregnated on or in granular carriers such as attapulgites or vermiculites, usually of particle size of about 0.3 to 1.5 mm. To prepare wettable powders, which can be dispersed in water or oil to

  any desired concentration of active compound, it may be

  poring wetting agents to a concentrated powder composition.

  In some cases, the active compounds are sufficiently

  They are soluble in common organic solvents, such as kerosene or xylene, so that they can be used directly in solution in these solvents. Frequently, herbicides can be dispersed under superatmospheric pressure, aerosolized. However, preferred liquid herbicide compositions are emulsifiable concentrates comprising an active compound according to the invention and, as an inert carrier, a solvent and an emulsifier. These concentrates can be diluted

  with water and / or oil, at any desired concentration -

  of active compound, to spray them onto the

  places of infestation. The emulsifiers most commonly used

  in these concentrates are non-ionic emulsifiers, or

  mixtures thereof and anionic surfactants.

  When using certain emulsifying systems, it is possible to

  prepare an inverted emulsion (water in oil) for

  directly apply to weeds.

  A typical herbicidal composition according to the invention is illustrated by the following example in which the amounts

are in parts by weight.

Example III

  Preparation of a dusting powder Product of Example 1 powdered talc 90 These ingredients are mixed in a grinder-mixer

  mechanics and crush them until we obtain a

  homogenous to flow, of the desired particle size. This powder is suitable for direct application to

place of infestation.

  d) Mixture of compounds, alone or in mixtures Although all the compounds presently described and represented by the general formula given are useful as herbicides, some are preferred for application to

  weeds. In general, one can use all

  described above, either singly or in a mixture between

  them. When used in a mixture, the ratio of a compound

  This can vary between 0.01 and 100.

  e) Mode of Application of the Compounds of the Invention The compounds of the invention can be applied as herbicides in any known manner. A method of controlling weeds is to contact the site where they occur with a herbicidal composition comprising

  an inert support and one or more of the compounds of the invention.

  as an essential active ingredient, in a toxic amount for these weeds. The concentration of the compounds of the invention in the herbicidal compositions varies greatly

  depending on the type of composition and is from 0.05 to 95%

  by weight. In a preferred embodiment of the invention,

  In addition, the herbicidal compositions may also include other pesticides, such as insecticides; nematicide,

  fungicides, etc., stabilizers, leveling agents,

  tinters, adhesives, pasting agents, fertilizers, activators,

synergies, etc.

  The compounds of the invention are also useful in

  sociation with other herbicides and / or defoliants,

  drying agents, growth inhibitors, etc., in the

  described above. These other bodies may represent

  about 5 to 95% of the active ingredients of the herbicidal compositions. By using associations according to the invention,

  more effective herbicidal compositions are obtained

  weeds and often giving unrealistic results with separate compositions of individual herbicides. f) Examples of other pesticides and herbicides for associations

  Other herbicides, defoliants, desiccants and

  plant growth promoters with which one can use

  compounds of the invention in the herbicidal compositions.

  may include: chlorophenoxy-2 herbicides

  me 2,4-D, 2,4,5-T, MCPA, Te MCPB, 4- (2,4-DB)! 4-CPB, 4CPA, 5-CPP, 2,4,5-TES, 3,4-DA, silvex, etc .; carbamate herbicides such as CPI, CPIC

  the swep, the barban, the BCPC, the CEPC, the CPPC, etc.

  type. thiocarbamate or dithiocarbamate such as CDEC, metamsodium, EPTC, diallate, PEBC, perbulate, vernolate, etc .; substituted urea herbicides, such as norea, siduron, dichloroalurea, chloroxyron, cycluron, fenuron, monuron, monuron TCA, diuron,

  linuron, monolinuron, neburon, buturon,

  turon, etc .; symmetrical triazine herbicides like

  Simazine, chlorazine, desmeryl, norazine, ipa.

  zine, prometryne, atrazine, trietazine, simetone, prometone, propazine, ametryne, etc. '; chloroacetamide herbicides such as chloro-N, N-dimethylacetamide,

  CDEA, SADC, 1'-chloro-N-isopropylacetamide, 2-chloroacetamide,

  N-isopropylacetanilide, 4- (chloroacetyl) morpholine, 1-

  chloroacetyl) piperidine, etc .; acidic herbicides

  chlorinated aliphatics, such as TCA, dalapon, 2,3-di-

  chloropropionic acid, 2,2,3-TPA, etc .; chlorinated benzoic and phenylacetic acid herbicides such as 2,3,6-TBA, 2,3,5,6-TBA, dicamba, tricamba, amiben, fenac, PBA, acid 2-methoxy-3, 6-dichlorophenylacetic acid, 3-methoxy-2,6-dichlorophenylacetic acid,

  2-methoxy-3,5,6-trichlorophenylacetic acid, 2,5-dichloroacetic acid

  ro-3-nitrobenzoic, the dual, metribuzin, etc .; and

  compounds such as aminotriazole, maleic hydrazide,

  phenylmercuric ketate, endothall, biuret, technical chlordane, dimethyl 2,3,5,6-tetrachlorotéraphthalate, diquat, erbon, DNC, DNBP, dichlobenil, DPAJ diphenamid, dipropalin , trifluralin, solan, dicryl, merphos, DMPA, DSMA, MSMA, potassium azide, acrolein, bovine, bensulfide, AMS, bromacil,

  2- (3,4-dichlorophenyl) -4-methyl-l, 2,4-oxadiazolidine-3,5-di-

  one, bromoxynil, cacodylic acid, CMA, CPMF, cypromid, DCB, DCPA, dichlone, diphenatril, DT, DNAP, EXD, ioxynil, isocil, Potassium cyanate, MAA, MAMA, MCPES, MCPP, MH, molinate, NPA, paraquat, PCP, picloram, DPA, PCA, phrichlor, sesone, terbacil, terbutol, TCBA,

  LASSO, planavin, sodium tetraborate, latcyanamide cal-

  such as DEF, ethylxanthogen disulfide, sindone,

  sindone B, propanil etc. It is also possible to use such

  bicides with the compositions of the invention in the form of their salts, esters, amides and other derivatives, whenever

  the progenitor compounds form such derivatives.

  g) Examples of weed control

  The following examples illustrate the usefulness of

  currently described for weed control. The described tests were performed in the laboratory, under laboratory conditions, with usual methods

laboratory.

Example IV

  When post-emergence 3-L5- (1-methoxy)

  ethyl) -1,3,4-thiadiazol-2-YLJ-4-hydroxy-l-methyl-2-imidazoli-

  dinone (example I) at a rate of 2.24 kg / ha to the following species

  weed control: Sida spinosa, different species of sesbania, Echinochloa crusgalli (L) (cockroach), Gossypium hirsutum (L) (gunner), Avena fatua (L) (wild oat), Datura stramonium (L) ( stramonia), sorghym halepense (L) (ale sorghum, Ipomoea purpura (L) Roth (great bindweed), Setaria glauca (L) (yellow foxtail) and Brassica kaber (L) (wild mustard), have been observed after 21 days, many of the grasses were so badly damaged that they could not recover and others were killed.

Example V

  When the same species were applied under the same conditions as in Example IV, 3-L5- [2- (1-methoxymethyl)

  ethyl-1,3,4-thiadiazol-2-yl] -4-hydroxy-1-methyl-2-imidazoline

  dinone, prepared in a manner similar to the compound of

  all species of weeds were growing.

  Although the invention has been described in detail in

  pos of certain examples of execution, it is understood that

these are not limiting.

Claims (12)

  1.Components having the formula: N (1) H S   Wherein X is an oxygen or sulfur atom, R is an alkyl group containing at most 4 carbon atoms, an alkenyl group containing at most 3 carbon atoms, an alkynyl group containing at most 3 carbon atoms or a haloalkyl group which may be a chloromethyl group; bromomethyl, 2-chloroethyl or 2-bromoethyl, and R 'is an alkyl group containing at most 4 carbon atoms. 2. Compound according to claim 1, characterized in that R 'is a methyl group.   3. Compound according to claim 1, characterized in that it is 3 - [5- (1-methoxyethyl) -1,3,4-thiadiazol-2-yl] -4-hydroxy-1-methyl. -2imidazolidinone. 4. A method of controlling weeds, characterized in that it consists in putting them in contact with a   effective amount of a compound according to any of the claims 1 to 3.   5.Procédé according to claim 4, characterized in that the   put in contact is done before the lifting.   Process according to claim 5, characterized in that   Weeds are found in a developing crop. 246-3138   7. Weed Control Procedure Spinal Sida   its, different species of Sesbania, Echinochloa crusgalli (cockroach), Avena fatua (wild oats), Datura stramonium   (Stramony dature), Sorghum halepense (Aleppo sorghum) Ipomoea purpu-   ra (great bindweed), Setaria glauca (yellow foxtail) and Brassica kaber (wild mustard), placed in a developing crop, characterized by contacting weeds before   emergence, with an effective amount of 3 - / - 5- / l- (ilmathylethoxy) -   ethyl-1,3,4-thiadiazol-2-yl 7-4-hydroxy-1-methyl-2-imidazolidinone.   8. Compound, characterized in that it corresponds to the formula: s H R '-X ---- NH2 (III) I   R in which X, R and R 'have the meaning indicated in the claim 1.   9. Compound, characterized in that it corresponds to the formula: R'I XH NCO (IV) R 12   in which X, R and R 'have the meaning indicated in the claim 1.   lOo.Composé, characterized in that it corresponds to the formula: HCOl -CH- (oÈH3) 2 (v) Z463138   in which X, R and R 'have the meaning indicated in claim 1o   11. Compound according to any one of claims 8 to   characterized in that R and R 'are methyl groups.   12. Process for the preparation of the compounds according to claim 1, characterized in that refluxing in an acidic medium is carried out.   a compound having the formula H Rw N-C-N-r-2-CH- (OC) (V) RCH3 in which: -   X is an oxygen or sulfur atom, R is an alkyl group containing not more than 4 carbon atoms, an alkenyl group containing not more than 3 carbon atoms, an alkynyl group containing not more than 3 carbon atoms, or a haloalkyl group which may be a chloromethyl, bromomethyl, 2-chloroethyl or 2-bromoethyl group, and R 'is an alkyl group containing at most 4 carbon atoms, and that the compound of formula I which forms is separated from the solution. 13.Procédé according to claim 12, characterized in that, to obtain the compound of formula V, is reacted a compound of formula IV H l R N_ 2 Roa 246-35138   X, R and R 'are as previously defined, dimethyl-   methylaminoacetaldehyde acetal and which is separated from the medium on Formula V compound formed.   14.Procédé according to claim 13, characterized in that, to obtain the compound of formula IV, a compound of formula III is reacted H S I R'-X-C 2 (III) I R   Y, R and R 'are as previously defined, on phosgene (COC12) in a common solvent and that the compound of formula IV which is formed.   15.Procédé according to claim 14, characterized in that the solvent is ethyl acetate   16. Method according to one of claims 12 to 15 -   characterized in that R 'is a methyl group.   17.Procédé according to claim 16, characterized in that   R is a methyl or ethyl group.