FR2463119A1 - SUBSTITUTED DIPHENYL ETHERS AND THEIR APPLICATION AS HERBICIDES - Google Patents

Abstract

SUBSTITUTE DIPHENYL ETHERS. THEY RESPOND TO THE FORMULA: (CF DRAWING IN BOPI) IN WHICH: A IS A HALOGEN ATOM OR A CYANO OR NITRO GROUP; X IS A HYDROGEN OR HALOGEN ATOM; Y IS A HYDROGEN OR HALOGEN ATOM OR A CYANO, TRIFLUOROMETHYL OR ALKYL GROUP CONTAINING 1 TO 4 ATOMS OF CARBON; Z IS AN ATOM OF OXYGEN OR SULFUR; R IS AN ALKYLENE GROUP, POSSIBLE MONOSUBSTITUTE, CONTAINING 1 TO 3ATOMS OF CARBON, THE SUBSTITUTE BEING AN ALKYL, OXOALKYL OR HYDROXYALKYL GROUP CONTAINING FROM 1 TO 4ATOMS OF CARBON; AND R IS AN ATOM OF HYDROGEN, AN ALKYL GROUP, OR ALCOXY CONTAINING FROM 1 TO 10ATOMS OF CARBON, A CYCLOALKYL GROUP CONTAINING FROM 3 TO 8ATOMS OF CARBON, AN AGRONOMICALLY ACCEPTABLE ION SPECIES, A PHENOMICALLY ACCEPTABLE PHENUBYL, A PHENUBYL, OR A PHENUBYL GROUP OR TRISUBSTITUDE SUBSTITUTE OF WHICH ARE HALOGEN ATOMS, ALKYL OR ALCOXY GROUPS CONTAINING 1 TO 10ATOMS OF CARBON, OR CYANO NITRO OR TRIFLUOROMETHYL GROUPS. APPLICATION AS A HERBICIDE.

Description

The present invention relates to substituted dyphenyl ethers having

  herbicidal activity, their preparation, and

  as their application to weed control.

  The subject of the invention is substituted diphenyl ethers.

  which, in their broadest sense, are represented by the following formula:

II II

- R> ___ <C - Z R

CF Q O Q- A

  in which: A / is a cyano nitro group or a halogen atom, X / is a hydrogen or halogen atom,

  Y / is a hydrogen or halogen atom, a cyano group, tri-

  fluroromethyl or alkyl containing from 1 to 4 carbon atoms,

  Z / is an oxygen or sulfur atom.

  R is an optionally substituted alkyl-ene group which is monosubstituted.

  with 1 to 3 carbon atoms, the substituent being an alkyl, oxoxalkyl, or hydroxyalkyl group having 1 to 4 carbon atoms, and R 1 is a hydrogen atom, an alkyl or alkoxy group of 1 to 10 carbon atoms, a cycloalkyl group containing

  3 to 8 carbon atoms, an agronomically acceptable ionic species

  or a phenyl group or a monosubstituted, disubstituted or trisubstituted phenyl group, wherein the substituent (s) are halogen atoms, alkyl groups, or alkoxy groups containing 10 carbon atoms, or cyano nitro or trifluoromethyl groups. Examples of halogens mentioned above are, for example, bromine, chlorine, iodine or fluorine, preferably

  bromine or chlorine. Alkyl and cycloalkyl groups are

  in the formula above, in particular the methyl groups,

  tyl, isobutyl, n-butyl, tert-butyl, n-amyl, heptyl, octyl, i.so-

  octyl, nonyl, decyl, cyclopropyl, ciclopentyl, cyclohlexyl, cyclohexyl,

  octyl, etc.Aloxy, oxoalkyl, and hydroxyalkyl groups

  are, for example, methoxy, ethoxy, butoxy, octoxy,

  oxoethyl, oxopropyl, oxobutyl, hydroxymethyl, hydroxyethyl, hy-

  hydroxypropyl, hydroxybutyl, etc. Examples of groups are:

  appropriate are the groups -.-, ylè ,, ethylen-etpropyl-

  As examples of species, it may be acceptable to specify, for example, alkali metals as sodium, potassium or lithium, alkaline earth metals such as barium or

  calcium, the ammonium ion, or the alkylammonium or alkanolammonium

  monium containing 1 to 4 carbon atoms.

  Preferred compounds according to the invention are those in which Z is an oxygen atom, A is a nitro group, R 1 is an alkyl group containing up to 4 carbon atoms, X

  hydrogen atom and Y a halogen atom.

  It has been possible to establish that the compounds according to the invention appear to have a herbicidal activity. Specific examples of compounds within the scope of the formula and preferred according to the invention are 5- (2-chloro-4-trifluoromethylphenoxy)

  -2- (ethoxycarbonyl) -4-methylpyrrobenzoates, ethoxylated

  carbonylmethyl) ethyl of 2'-ethoxycarbonyl, 2 '- (thoxycarbonyl)

  bonyl) ethyl, - (ethoxycarbonyl) methyl, ethoxycar

  2 '- (ethoxycarbonyl) butyl, 2' - oxopropyl,

  noxycarbonyl) ethyl, 1 '- (ethoxycarbonyl) propyl, 1'-ethoxy

  xycarbonyl-3'-methyl-butyl, <- (2-chloro-trifluoromethyl)

  phenoxy) -2-bromobenzoate of 1 '- (ethoxycarbonyl) ethyl, the

  5- (2-Chloro-4-trifluoromethylphenoxy) -2-nitrobenzoate of 1 '- (-

  thoxycarbonyl) -2'-hydroxypropyl, 5- (2-chloro-4-trifluoro-

  1 - (ethoxycarbonyl) etbyl methylphenoxy) -2-cyanobenzoate, 5- (2,6-dichloro-4-trifluoromethylphenoxy) -2-nitrobenzoate

  of 1- (ethoxycarbonyl) ethyl, 5- (2-chloro-6-bromo-4-trihydro)

  1 '- (ethoxycarbonyl) fluoromethylphenoxy-2-cyanobenzoate

  thyl and 5- (2-chloro-4-tetrafluoromethylphenoxy) -2-nitrobenzoate

  (- (thioethylcarbonyl) ethyl acetate.

  Of course, the stereoisomers and the isomers op-

  ticks of the compounds of the above formula also fit

in the context of the invention.

  In practice, in order to synthetically prepare the compounds of the invention, a benzoyl halide suitably substituted with an appropriately substituted α-hydroxycarboxylic acid or alcohol ester, for example, is reacted, or

  a benzoic acid which is suitably

  killed on a suitable c-halocarboxylic acid ester

  replaced by known techniques. The substituted benzoyl halides (or

  the corresponding acids) and the z-hydroxycarb

  boxyl or substituted halogenocarboxylic acid, or prepa-

  by known techniques. In particular, we have

  Stirred with stirring at least a stoichiometric amount of benzoyl halide substituted with the acid-hydroxycarboxy-

  substituted, preferably in the presence of an acceptor of

  such as triethylamine, pyridine, N, N-dimethyl-

  line, etc.- Since the reaction is essentially exo-

  By thermal, the substituted benzoyl halide is functionally added such that the temperature of the mixture does not substantially exceed about 35 ° C. When preparing the compounds of the invention by reacting a substituted benzoic acid

  on a "-halocarboxylic acid" ester, it is preferable to add

  the second to the first in the presence of an azo compound such as 1,5-diazobicyclo (5.4.0) undec-5-ene (DBU). In one or the other synthesis method, it is possible, if desired, to carry out the reaction in the presence of an inert solvent such as

  benzene, methylene chloride, chloroform, acetic acid,

  of ethyl, tetrahydrofuran, etc.-When we have finished

  benzoyl halide substituted for the acid ester "-hy-

  droxycarboxylic acid (or add the "-halogenoear-

  boxylic acid with substituted benzolac acid), the mixture is heated

  at reflux and maintained at reflux until the reaction

  be completed to the extent desired. The mixture is then cooled to room temperature and, in practice, washed successively with dilute acid, dilute base and water, and the phases are allowed to separate. The substituted diphenyl ether contained in the aqueous phase is recovered by any known technique, for example by evaporation, crystallization,

  vacuum drying, etc. If desired, we can still purify

  proud of the product which is the substituted diphenyl ether, by

example by recrystallization.

  Examples I to XII below illustrate the synthesis of some of the substituted diphenyl ethers conforming to

the invention.

Example I

  - (Ethoxycarbonyl) ethyl (2-chloro-4-trifluoromethylphenoxy) -2-nitrobenzoate. In a 100 cc 3-necked flask equipped with an addition funnel, reflux condenser and magnetic stirring bar, 1.18 g (0.01 mol) of lactate were introduced. ethyl and 0.79 g (0.01 mol) of pyridine in 30 cm3 of benzene. To the stirred solution, at room temperature (about 20 ° C), 3.79 g (0.01 mole) was added dropwise.

  5- (2-chloro-4-trifluoromethylphenoxy) -2-nitro-

  benzoyl in 20 cm3 of benzene. Exothermic heating was observed. Once the addition is complete, the

  Refluxed and refluxed for 6 hours.

  0O then cooled the mixture, transferred it to an enton-

  decantation and washed successively with

  30 cm3 of 1N hydrochloric acid, water, 1N sodium hydroxide and water. The washed organic phase was dried over

  magnesium sulphate and concentrated in a rotary evaporator

  at 55 ° C. to obtain 2.89 g of a light yellow oil, which

  it has been identified as 5- (2-chloro-4-trifluoromethyl)

  phenoxy) -2-nitrobenzoate of - (ethoxycarbonyl) ethyl whose nuclear magnetic resonance spectrum, NMR (in acetone, d6) was as follows: 7.3 to 8.34 (complex multiplet, 6H),, 5 (quartet, H), 4.28 J (quartet, 2H), 1.62 S (doublet, 3H),

1.25 S (triplet, 3H).

Example II

  - (2-chloro-4-trifluoromethylphenoxy) -2-nitrobenzoate

thoxycarbonylmethyl) ethyl.

  In a 100 cc three-necked flask equipped with an addition funnel, a reflux condenser and a magnetic stir bar, 1.32 g (0.01 mol) of

  Ethyl 3-hydroxybutyrate and 1.1 g (0.01 mole) of triethyl

  mine in 30 cc of benzene. At the agitated solution, at the temperature

  ambient temperature (about 20 C), we added drop-wise

  , 69 g (0.01 mole) of 5- (2-chloro-4-trifluoromethyl) chloride

  phenoxy) -2-nitrobenzoyl in 20 cm3 of benzene. Once the ad-

  finished, the mixture was heated to reflux and was

  kept at reflux for 6 hours. We then cooled the

  lange, it was transferred to a separatory funnel and was

  washed successively with 30 cm3 fractions of chloroacid

  1N hydride, water, 1N sodium hydroxide and water. The washed organic phase was dried over magnesium sulfate and concentrated on a rotary evaporator at 55 ° C. to obtain 3.5 g of a brown oil which was identified as - (2- 4 '- (methoxycarbonylmethyl) ethyl chloro-4-trifluoromethylphenoxy) -2-nitrobenzoate, NMR (acetone, a6) 7.2 to 8.3, (complex multiplet, 6H); 5.5 i (quartet, 1H), 4.15 s (quartet, 2H), 2.75 (doublet, 2H),

  1.3 i (triplet overlapping doublet, 6H).

Example III

  5- (2-chloro-4-trifluoromethylphenoxy) -2-nitrobenzoate of 2'-e-

  thoxycarbonyle. In a 250 cc three-necked flask equipped with an addition funnel, an Xeflux condenser and a magnetic stir bar, 2.70 g (0.03 mol) was introduced.

  of 3-hydroxypropionic acid and 2.38 g (0.03 mol) of pyridine

  dine in 100 cm3 of methylene chloride. To the agile solution

  at room temperature (about 20 C), we added

  dropwise 11.37 g (0.03 mole) of 5- (2-chloro-4-

  trifluoromethylphenoxy) -2-nitrobenzoyl in 30 cm3 of methylene chloride. Exothermic heating was observed. After the addition was complete, the mixture was heated to reflux and

  it was kept at reflux for 22 hours. We then cooled

  The mixture was transferred to a separatory funnel and washed twice with 100 cc portions of 1N hydrochloric acid and once with 100 ml of water. The washed organic phase was dried over magnesium sulfate and concentrated on a rotary evaporator at 55 ° C to obtain 11.8 g of a viscous yellow oil identified as - (2-chloro-4- 2'-ethoxycarbonyl trifluoromethylphenoxy) -2-nitrobenzoate, NMR (acetone, d6): 7.2-8.4 (complex multiplet, 6H), 4.3 (triplet, 2H),

2.67 (triplet, 2H).

Example IV

  2'-thoxycarbonyl) ethyl (2-chloro-4-trifluoromethylphenoxy) -2-nitrobenzoate In a 100 cc three-necked flask equipped with an addition funnel, a reflux condenser and a bar magnetic stirring, 20 cm3 of ethanol and 5 cm3 were introduced.

  pyridine in 30 cm3 of methylene chloride. At the solution

  stirring at room temperature (about 20 C), we have

  Dropped 2.26 g (0.005 mole) of 5- (2-chloro-4-triad)

  2 '- (chlorocarbonyl) fluoromethylphenoxy) -2-nitrobenzoate

  thyl in 15 cm3 of methylene chloride. After the addition was complete, the mixture was refluxed and refluxed for 42.5 hours. We then cooled the mixture

  and concentrated on a rotary evaporator at 55 ° C.

  The concentrated residue was taken with 100 cm3 of methylene chloride, transferred to a separatory funnel and washed.

  successively with 30 cm3 fractions of hydrochloric acid

  than 1N, water, 7% ammonium hydroxide, and water. The washed organic phase was dried over magnesium sulfate and concentrated on a rotary evaporator at 55 ° C to obtain 1.3 g of a yellow oil which was identified as - (2- 2 '- (methoxycarbonyl) ethyl chloro-4-trifluoromethylphenoxy) -2-nitrobenzoate, NMR (chloroform): 7.0 to 8.1 J (multiplet, 6H), 4.3; (multiplet, 4H), 2.65 (triplet, 2H), 1.3 i (triplet, 3H),

Example V

  - (methoxycarbonyl) methyl (2-chloro-4-trifluoromethylphenoxy) -2-nitrobenzoate in a 100 cc three-necked flask equipped with a

  addition funnel, a reflux condenser and a bar-

  1.25 g (0.012 mole) of ethyl glycolate and 0.80 g (0.01 mole) of pyridine in

  35 ml of ethylene chloride. At the agitated solution, at the

  at room temperature (about 20 C), was added dropwise

  3.79 g (0.01 mole) of 5- (2-chloro-trifluoromethyl) chloride

  phenoxy) -2-nitrobenzoyl in 20 ml of methylene chloride.

  Exothermic heating was observed. Once the addition

  The mixture was heated to reflux and heated.

  held at reflux for 42.5 hours. We then cooled the

  The mixture was transferred to a separatory funnel and washed successively with 30 cc portions of 1N hydrochloric acid, water, aqueous ammonium hydroxide 75, and water. The washed organic phase was dried over magnesium sulfate and concentrated on a rotary evaporator at 55 ° C.

  to obtain 3.5 g of a yellow oil that has been identified as

  being 5- (2-chloro-4-trifluoromethylphenoxy) -2-nitrobenzene

  - (ethoxycarbonyl) methyl zoate, NMR (chloroform): 7.0-8.4f (multiplet, 6H), 4.82 (singlet, 2H) $ 4.25 (quartet, 2H), 1.31 ( triplet, 3H)

Example VI

  Ethoxycarbonyl-2'-oxopropyl (2-chloro-4-trifluoromethylphenoxy) -2-nitrobenzoate in a 100 cc three-necked flask equipped with an addition funnel, a reflux condenser and a 'a bar

  magnetic stirring, 3.61 g (0.01 mol) of

  5- (2-chloro-4-trifluoromethylphenoxy) -2-nitrobenzoic acid and 1.53 g (0.01 mole) of 1,5-diazabicyclo (5.4.0) undea-5-ene (DBU) in 50 cm3 of benzene. To the stirred solution at room temperature (about 20 ° C) was added 1.65 g (0.01 mole) of ethyl 2-chloroacetoacetate, the mixture was then refluxed and maintained. at reflux for 20.5 hours. The mixture was then cooled, transferred to a separatory funnel and then washed with 30 cm 3 of 1N hydrochloric acid, water, 7% aqueous ammonium hydroxide. , and water. The washed organic phase was dried over magnesium sulfate and concentrated on a rotary evaporator at 55 ° C. to give 3.1 g of a brown oil, which was

  identified as 5- (2-chloro-4-trifluoromethylphenyl)

  1-ethoxycarbonyl-2'-oxopropyl -2-nitrobenzoate, NMR (acetone, d6): 7.2-8.2 (multiplet, 6H),, 8 S (singlet, 1H), 4.2 5 (quartet, 2H)

2.3 (singlet, 3H).

Example VII

  1 '(ethoxycarbonyl) butyl (2-chloro-4-trifluoromethylphenoxy) -2-nitrobenzoate in a 100 cc three-necked flask equipped with an addition funnel, a reflux condenser and a bar magnetic stirring, 3.61 g (0.01 mol) of 5- (2-chloro-4-trifluoromethylphenoxy) -2-nitrobenzoic acid were introduced.

  and 1.53 g (0.01 mol) of DJBU in 50 ml of benzene. At the solution

  After stirring at room temperature, 2.19 g (0.01 mol) of ethyl 2-bromovalerate was added. We then heated the

  Refluxed and refluxed for 22 hours.

  The mixture was then cooled, transferred to a

  decanation funnel and washed successively with 30 cc fractions of 1N hydrochloric acid, 7% aqueous ammonium hydroxide water and water. The organic phase was dried

  washed over magnesium sulphate and concentrated in the

  rotary evaporator at 55 C to obtain 2.2g of a brown oil

  that has been identified as 5- (2-chloro-4-trifluoro-

  methyl (-2-nitrobenzoate) -2- (ethoxycarbonyl) butyl, NMR (a-

  ketone, d6): 7.2 to 8.2 (multiplet, 6H),, 25. (triplet, 1H), 4.28 (quartet, 2H),

0.8 to 1.95 (multiplet, 10H).

Example VIII

  (1-phenoxycarbonyl) ethyl (2-chloro-4-trifluoromethylphenoxy) -2-nitrobenzoate In a 100 cc three-necked flask equipped with an addition funnel, a reflux condenser and a bar of magnetic stirring, 3.61 g (0.01 mol) were introduced

  5- (2-chloro-4-trifluoromethylphenoxy) -2-nitrobenzoic acid

  and 1.53 g (0.01 mol) of DBU in 50 cm3 of benzene. To the stirred solution at room temperature (about 20 ° C) was added 2.29 g (0.01 mol) of phenyl 2-bromoacetate. We have

  the mixture was heated to reflux and maintained

  flow for 22.5 hours. The mixture was then cooled, transferred to a separatory funnel and washed.

  successively with 30 cm3 fractions of hydrochloric acid

  than 1N, water, 1N sodium hydroxide, and water. The washed organic phase was dried over magnesium sulfate and concentrated on a rotary evaporator at 55 ° C. to obtain 2.58 g of a light green syrupy liquid which was identified as 5- ( 2 - (4-phenoxycarbonyl) ethyl 2-chloro-4-trifluoromethylphenoxy) -2-nitrobenzoate, NMR (acetone, d6): 7.0 to 8.25 S (multiplet, 11H), 5.5 '(quartet, 1H),

1.68 i (doublet, 3H).

Example IX

  (1-ethoxycarbonyl) propyl (2-chloro-4-trifluoromethylphenoxy) -2-nitrobenzoate in a 100 cc three-necked flask equipped with a

  addition funnel, a reflux condenser and a bar-

  With magnetic stirring, 3.61 g (0.01 mole) of 5- (2-chloro-4-trifluoromethylphenoxy) -2-nitrobenzoic acid was introduced.

  and 1.53 g (0.01 mol) of DBU in 35 ml of benzene. At the solution

  After stirring at room temperature (about 20 ° C), 1.95 g (0.01 mol) of ethyl 2-bromobutyrate in 15 cm3 of benzene was added dropwise. There was a warm-up

  exothermic. Once the addition is complete, the heat has been heated.

  Refluxed and refluxed for 24 hours.

  The mixture was then cooled, transferred to a

  decanation funnel and washed successively with 30 cc portions of 1N hydrochloric acid, water, 7% aqueous ammonium hydroxide and water. The organic phase was dried

  washed over magnesium sulphate, it was concentrated in the

  rotator at 55 ° C. and 1.2 g of a liquid having

  rupous light brown that has been identified as 5- (2-

  4-chloro-4-trifluoromethylphenoxy) -2-nitrobenzoate

  xycarbonyl) propyl, NMR (acetone, d6): 7.2 to 8.2 (multiplet, 6H), 5.15 g (triplet, H), 4.2 (quartet, 2H), 1.9 sec ( quartet, 2H),

  0.8 to 1.3 i (overlapping triplets, 6H).

Example X

  - 'Ethoxycarbonyl-3'-methylbutyl (2-chloro-4-trifluoromethylphenoxy) -2-nitrobenzoate In a 100 cc three-necked flask equipped with an addition funnel, a reflux condenser and a bar

  magnetic stirring, 1.60 g (0.01 mol) of

  ethyl hydroxyisoopaproate and 0.79 g (0.01 mol) of pyridine in 40 cm3 of methylene chloride. To the stirred solution, at room temperature (about 20 C), was added dropwise to

  drop 3.79 g (0.01 mole) of 5- (2-chloro-4-trifluoromethyl) chloride

  oromethylphenoxy) -2-nitrobenzoyl in 10 ml of methylene chloride. Exothermic heating was observed. After the addition was complete, the mixture was heated to reflux and kept under reflux for 46> 5 hours. The mixture was then cooled, transferred to a settling funnel and

  it was washed successively with 25 cm3 fractions of

  1N hydrochloric acid, water, aqueous ammonium hydroxide

  3.5% and water. The washed organic phase was dried over sodium

  magnesium fate and concentrated on a rotary evaporator at 55 ° C. to obtain 3.99 g of a viscous brown oil which is

  identified as 5- (2-chloro-4-trifluoromethylphenol)

  xy) -2-ethoxycarbonyl-2-nitrobenzoate, NMR (acetone, d6): 7.2-8.3; (multiplet, 6H),, 2 i (triplet, 1H); 4.2 i (quartet, 2H) 1.8 & (multiplet, 3H),

0.8 to 1.4 (multiplet, 9H).

Example XI

  1'-Ethoxycarbonyl-2'-hydroxypropyl (2-chloro-4-trifluoromethylphenoxy) -2-nitrobenzoate in a 500 cc three-necked flask equipped with an addition funnel, a reflux condenser and a reflux bar. 19.56 g (0.04 mole) of 1'-ethoxycarbonyl-2'-oxopropyl (2-chloro-4-trifluoromethylphenoxy) -2-nitrobenzoate (prepared according to Example VI) were introduced into cm3 of methanol. . To the agitated solution, to the temperature

  At room temperature (ca. 20 ° C), 3.14 g (0.05 mole) of cyano was added.

  sodium noborohydride and a few drops of methyl

ill

  orange. Chloro acid solution was added dropwise.

  2N hydride and 75:25 methanol (by volume) at a sufficient flow rate

  to maintain the color of the indicator, we then

  The mixture was refluxed and maintained at reflux for

  after 20 hours, then the mixture was cooled and

  55 ° C. The residue was taken up in a rotary evaporator at 55 ° C.

  centered with 200 cm3 of diethyl ether, was transferred to a separatory funnel and washed successively with 100 cm3 portions of 1N hydrochloric acid, water, 1 N sodium hydroxide and 1 N sodium hydroxide. 'water. We then dried the phase

  washed on magnesium sulphate and was concentrated in

  The mixture was rotary evaporated at 55 ° C. to obtain 18.1 g of yellow syrupy liquid, which was identified as 1-ethoxycarbonyl-2-hydroxypropyl-2-chloro-4-trifluoromethylphenoxy-2-nitrobenzoate. NMR (acetone, d6): 7.2-8.5 (multiplet, 6H), 4.2d (multiplet, 3H), 3.2 (quartet, 2H),

  1.3 "((doublet overlapping triplet, 5H).

  Example XII - (Ethoxycarbonyl) ethyl (2-chloro-4-trifluroromethylphenoxy) -2-bromobenzoate In a 100 cc three-necked flask equipped with an addition funnel, a reflux condenser and a A manetic stirring bar was charged with 1.18 g (0.01 mole) of ethyl lactate and 0.79 g (0.01 mole) of pyridine in cm 3 of methylene chloride. To the agitated solution, to the

  at room temperature (about 20 C), was added dropwise

  2.07 g (0.005 mole) of 5- (2-chloro-4-trifluoro-

  methylphenoxy) -2-bromobenzoyl in 10 cm3 of

  thylène. Exothermic heating was observed. After the addition was complete, the mixture was refluxed and refluxed for 66 hours. The mixture was then cooled, transferred to a settling vessel.

  and washed successively with 30 cc fractions of

  1N hydrochloric acid, water, aqueous ammonium hydroxide

  7% and water. The washed organic phase was dried over sodium

  magnesium fate and concentrated on a rotary evaporator at 550 ° C. to obtain 2.2 g of viscous yellow syrupy liquid,

  that has been identified as 5- (2-chloro-4-trifluoromethyl)

  (methoxycarbonyl) ethyl) -2-bromobenzoate, NMR (actene, d6): 7.0 to 8, oe (multiplet, 6H),, 6 (quartet, 1H), 4.18 (doublet) , 5H), 1.68 C (doublet, 3H),

1.18 ((triplet, 6H).

  Although we have described in some detail

  in Examples I to XII above, the synthesis of compounds of the invention

  However, it is understood that those skilled in the art can prepare any compound within the scope of the invention simply by playing on the choice of raw materials and using the techniques described herein. any other appropriate techniques.

  It has been found that the compounds of the invention are

  ficaces to control the growth of various inde-

  sirables, that is to say, weeds, when they are

  as herbicides, in an effective amount, in the growth medium, before emergence, or after emergence. The effective amount is the amount of a compound or mixture of compounds that is required to cause weeds harm such that they are unable to recover

  after the application. The amount of a compound or mixture of compounds

  applied for a satisfactory herbicidal effect.

  making can vary in a wide range and depends on various factors, for example the resistance of a species, particular weeds, degree of infestation, climatic conditions, soil condition, mode of application, etc. . In practice, sometimes only 0.22 kg / ha is required, and up to

  11.2 kg / ha or more of compound or mixture of compounds.

  Of course, the effectiveness of a particular compound against a particular species of weed can easily be determined by relatively simple laboratory tests.

  or in the field, in a well-known way.

  The compounds according to the invention can be used

  as such or in combination with acceptable agronomic adjuvants

  inert carriers, other herbicides or other compounds commonly used in agriculture, eg pesticides, stabilizers, preservatives, fertilizers, etc. The compounds of the invention, whether or not associated with other agronomically acceptable bodies,

  in practice in the form of powders for

  coating, granules, wettable powders, solutions, suspensions, aerosols, emulsions, dispersions, etc., in a well-known manner. When associated with other bodies

  classically used and agronomically acceptable, the quan-

  of the compounds of the invention in the composition may vary.

  wide range, for example between 0.05 and 95%

  viron of the weight of the composition. Advantageously, these compounds

* contain approximately 5 to 75% by weight of the compound (s)

according to the invention.

  The compounds according to the invention have been found effective

  to control various broadleaf weeds

  and grasses at 2.24 kg / ha, as pre-treatment.

  or post-emergence, without significantly damaging the cul-

  such as maize, wheat, rice and soybeans. Examples of weeds that can be effectively controlled by applying the compounds of the invention are field mustard (Brassica kaber), yellow foxtail (setaria glauca), blood red midge (Digitaria sanguinalis),

  different species of Sesbania, the velvetleaf (velvetleaf)

  phrasti), the sorghum of Aleppo (Sorghum halepense), the panicoot of cock (Echinochloa crusgalli), the dyed stramony (Datura stramonium), the Sidaspinosa, the great bindweed (Roth) etc. Some of the compounds prepared according to Examples I-XII were tested for their herbicidal activity against

  certain weed species under controlled conditions.

  lighting, temperature and humidity in the laboratory.

  For these trials, selected weed seeds were planted in clusters. For the pre-emergence tests, the shelves were treated with the selected compound immediately after sowing. For the post-emergence tests, the shelves were treated with the selected compound after a germination time of two weeks. The compound was applied to the shelves by spraying a solution of the compound into

  solvent at the indicated dose, the growth status was observed.

  weed and we evolved periodically after

  the application, the toxic effect of the compound.

  The following table indicates the weed species and the applied compound (indicated by an "X" in the column of the example in which it is prepared). In each case, the pre-emergence compound was applied to a

dose of 2.24 kg / ha.

  In each of the above trials, all weeds were killed or it was observed that

  not to recover, within the next 21 to 22 days

  application of the particular compound.

COMPOUND GRASS

  I II IV VI VIIVII IX X Sida spinosa X X X X dature stramony X X X X X X X X X Mustard X X X X X X X X Green foxtail X X X X X X X X blood X X X X X X X X Aleppo sorghum X X X X X X X sesbania spp. X X X X X velvet X X X X X broad bindweed X X X X wild oats X X X rooster X X X X X X X -

  The following table concerns the application in

  postemergence at a rate of 2.24 kg / ha.

  In each of the trials, it was observed that all weeds were killed or damaged to the point of

  to recover, within 21 to 22 days of application

of the particular compound.

  It has been observed that the compounds according to the invention in which the substituent A is other than a nitro group, for example a halogen atom, and more especially a bromine atom (for example the compound prepared according to Example XII ) had a slightly better herbicidal activity when

I I III IV VI VI VII VI X

  Sida spinosa X X X X d. Fingrams X X X X X X X X X wild mustard X X X X X X X X X X green foxtail X X X X X X X blood panic X Aleppo sorghum X X X X Sesbania spp. XXXXXXXXXX velvet XXXXXX large bindweed x large bindweed XXXX XXXXX wild oats XXXX panic rooster XXX thimble XX _ applied them post-emergence rather than pre-emergence, at doses below 5.6 kg / ha, for example at 2.24 kg / ha or less. The invention has been described in great detail in connection with examples but it is understood that these are not

  and that the person skilled in the art will be able to bring

  many changes without departing from the scope of the invention.

l7

Claims (8)

  (1) compound, characterized by the fact that it meets the   wherein X is a halogen atom or a cyano or nitro group, X is a hydrogen or halogen atom, Y is a halogen atom or a cyano or nitro group, X is a hydrogen or halogen atom, Y is a hydrogen or halogen atom or a cyano, trifluoromethyl or alkyl group containing from 1 to 4 carbon atoms, Z is an oxygen or sulfur atom,   ] R / is an alkyl group e =, possibly monosubstituted,   from 1 to 3 carbon atoms, the substituent being a   alkyl, oxoalkyl or hydroxyalkyl group containing 1 to 4 carbon atoms my carbon, and   R1 is a hydrogen atom, an alkyl or alkoxy group   from 1 to 10 carbon atoms, a cycloalkyl group   from 3 to 8 carbon atoms, an acceptable ionic species   agronomically, a phenyl group or a mono phenyl group   substituted, disubstituted or trisubstituted with substituents   are halogen atoms, alkyl or alkoxy groups containing   from 1 to 10 carbon atoms, or cyano, nitro groups or trifluoromethyl ..   2) A compound according to claim 1, characterized in that Z is an oxygen atom.   3) A compound according to claim 1, characterized in that R1 is an alkyl group containing at most 4 atoms (carbon.   4) Composed according to claim 1, characterized in what A is a nitro group.   Compound according to claim 1, characterized   That A is a halogen atom or a cyano group.   6) Compound according to claim 1, characterized in that A is a nitro group, Z is an oxygen atom, R1 is an alkyl group containing at most 4 carbon atoms,   X is a hydrogen atom and Y is a halogen atom.   7) A compound according to claim 1, characterized in   what is selected from 5- (2-chloro-4-trifluoromethylphenyl)   noxy) -2-nitrobenzoates of 1 '- (ethoxycarbonyl) ethyl, of 1' - (e-   2 '- ethoxycarbonyl, 2' (ethoxycarbonyl) ethyl, 1 '- (ethoxycarbonyl) methyl, ethoxycarbonyl - 2' oxopropyl, - (ethoxycarbonyl) butyl, (2 '- ethoxycarbonyl) ethyl, phenoxycarbonyl) ethyl, or 1 '- (ethoxycarbonyl) -propyl ethoxycarbonyl-3'-methylbutyl or 1'-ethoxycarbonyl   -2'-hydroxypropyl or 5- (2-chloro-4-trifluoromethylphenoxy) -   2-bromobenzoate of - (ethoxycarbonyl) ethyl.   8) Herbicidal composition, characterized in that   contains, in an effective amount, a compound or mixture of compounds poses according to claim 1.   9) A method of controlling weed growth by applying an herbicide in an amount effective to either the growth medium prior to emergence of the weeds or to the weeds after emergence, characterized by the use of a compound or mixture of compounds according to claim 1