CH624087A5 - Process for the preparation of phenoxyphenoxypropionic acid derivatives - Google Patents

Description

The present invention relates to a process for the preparation of compounds of the formula I.

(Vn

ch.

o-ch-ch2-ch2-z

(I)

wherein

R, halogen, —CF3 or (Ci-C4) alkyl,

Z the groups —CN, -CS-NH2, —CO-R2 or -CH2-Ü-R3,

65 R2 hydroxy, -O-Kat, (Cr-C ^ J-alkoxy, which may be replaced by -OH, halogen, -CF3, (Cj-C6) alkoxy, (C, -C4) alkylthio, phenyl, phenoxy or Halogenphenoxy can be substituted; residues of the formulas

624 087

4th

-och

-och

-ochj1

(° C2 "4) 2_3 ocmh2m + 1, -oc2h4-n;

-0CoH.-N A, 2 4 v. /

- (C ^ -C ^) alkyl

V (C1 ~ C4) alkyl

-n

(R,)

In

0

oh under basic conditions with a y-valeric acid derivative of the formula III

20th

CH3 I

Y-CH-CH2CH2Z

(III)

represents the pyrrolidinyl, piperidinyl, morpholinyl or N-methyl-piperazinyl radical; (C5-C6) cycloalkyl, which may optionally be substituted by (C1-C4) alkyl and / or halogen; (C3-C4) -alkenyloxy, cyclohexenyloxy, (C3-C4) -alkynyloxy, which may optionally be substituted in the 1-position by (Ci-C4) -alkyl and / or phenyl; Phenoxy, which may optionally be substituted by halogen, -N02 and / or (Ci-C4) -alkyl; (Cr-C ^ alkylthio, allylthio, phenylthio, Ha-logenphenylthio, amino, (C1-C4) alkylamino, hydroxyethylamino, di (C; [- C4) alkylamino, pyrrolidino, piperidino, morpholino; Anilino, which may optionally be substituted by halogen, -CF3 and / or (Q-GO-alkyl), and hydrazino,

R3 is hydrogen, (Ci-C4) -alkyl, (C1-C4) -alkylcarbonyl, halogen (C! -C4) -alkylcarbonyl, benzoyl, which is optionally substituted by halogen, -N02 and / or (C1-C4) -alkyl ; (C1-C4) alkylcarbamoyl, di- (Cj-C4) alkylcarbamoyl, phenyl-carbamoyl, which may optionally be substituted by halogen and / or (Cj-C4) alkyl; (C1-C4) alkylsulfonyl, phenylsulfonyl, -S03H or -S03Kat as well

Kat the cation equivalent of an inorganic or organic base,

n is a number from 1 to 3 and m is a number from 1 to 6.

Kat primarily stands for cation equivalents of inorganic bases, such as Na +, K +, v2 Ca ++ and v2 Mg ++, furthermore for NH4 + and cations of organic amines, such as the various aliphatic mono-, di- or trialkylamines, the corresponding triethanolamines, aniline, methylaniline , Benzyf amines and Diphenylamines. Shark preferably means chlorine or bromine.

If the radicals R2 or R3 contain substituted phenyl groups as constituents, the latter contain up to three, but preferably one, substituent. If this substituent is an alkyl group, methyl or ethyl are preferred.

The compounds of the formula I are prepared according to the invention by a) substituting a substituted phenoxyphenol of the formula II

reacted, where Y is halogen, preferably bromine or chlorine, or b) a substituted phenoxyphenol of the formula II under basic conditions with y-valerolactone of the formula IV

30th

35

40

45

50

55

60

(ii)

(iv)

implements.

Variant a) is generally carried out at from 20 ° C. to the boiling point of the mixture, preferably at from 80 ° to 160 ° C., in an inert solvent such as toluene, xylene, dimethylformamide or dimethyl sulfoxide. Alkali or alkaline earth metal carbonates or hydroxides or tertiary organic amines such as pyridine or triethylamine are preferably used as basic agents.

In variant b), the reaction is generally carried out with an equivalent or excess amount of y-valerolactone (IV) at temperatures from 100 to 240 ° C., preferably between 160 and 220 ° C. The compounds of formula II are preferably used as alkali phenolates. The reaction can be carried out with or without a solvent.

The compounds of formula I obtained can be converted into other compounds of formula I by further, generally known reactions, for. B. by saponification, esterification, amidation, dehydration, reduction or oxidation. The functional group Z = COOH can e.g. B. with halogenating agents (z. B. SOCl2) in acid halides, with amines in amides, with bases in carboxylic acid salts with alcohols in esters.

Esters can also by reacting the corresponding acid halide with alcohols or by alkylating salts of the acid e.g. B, by means of halogen compounds or dialkyl sulfates.

The functional group Z = CN can e.g. by dehydration of primary amides (Z = CONH2) with phosphorus pentoxide, the functional group Z =

65

nh.

5

624 087

e.g. B. by addition of hydrogen sulfide to nitriles (Z = CN), the functional group Z = -CH2OH z. B. can be obtained by reducing the ester function using lithium aluminum hydride. These methods are generally known and familiar to the person skilled in the art.

The compounds of formula I obtained according to the invention show good herbicidal activity against a number of important harmful grasses in the pre- and post-emergence process.

On the other hand, high doses due to dicotyledonous crops and various types of cereals are well tolerated, so that these compounds are particularly suitable for the selective control of harmful grasses in agricultural crops.

In herbicidal compositions, the active compounds of the formula I are generally used in amounts of 2-95% by weight. They can be used as wettable powders, emulsifiable concentrates, sprayable solutions, dusts or granules in the usual preparations.

Wettable powders are preparations that are uniformly dispersible in water. In addition to the active ingredient, they contain wetting agents such as a diluent or an inert substance. B. polyoxyethylated alkylphenols, polyoxethylated oleyl or stearylamines, alkyl or alkylphenyl sulfonates and dispersants, e.g. sodium lignosulfonate, 2,2'-dinaphthylmethane-6,6'-disulfonic acid sodium or oleylmethyl tauric acid sodium.

Emulsifiable concentrates are obtained by dissolving the active ingredient in an organic solvent, e.g. B. butanol, cyclohexanone, dimethylformamide, xylene or higher-boiling aromatics and addition of a non-ionic surfactant, for example a polyoxyethylated alkylphenol or a polyoxyethylated oleyl or stearylamine.

Dusts are obtained by grinding the active ingredient with finely divided, solid substances, e.g. B. talc, natural clays such as kaolin, bentonite, pyrophillite or diatomaceous earth.

Sprayable solutions, as they are often traded in spray cans, contain the active ingredient dissolved in an organic solvent. B. as a blowing agent, a mixture of chlorofluorocarbons and / or carbon dioxide.

Granules can either be produced by spraying the active ingredient onto adsorbable, granulated inert material or by applying active ingredient concentrates by means of adhesives, e.g. B.'Polyvinyl alcohol, polyacrylic sodium or mineral oils on the surface of carriers such as sand, kaolinite, or granulated inert material. Suitable active ingredients can also be produced in the manner customary for the production of fertilizer granules - if desired in a mixture with fertilizers.

In the case of herbicidal compositions, the concentrations of the active compounds in the commercial formulations can vary. In wettable powders the active ingredient concentration varies e.g. B. between about 10 and 95%, the rest consists of the formulation additives specified above. In the case of emulsifiable concentrates, the active substance concentration is approximately 10 to 80%. Dust-like formulations usually contain 5 to 20 '/ c of active ingredient, sprayable solutions about 2 to 20%. In the case of granules, the active ingredient content depends in part. depends on whether the active compound is liquid or solid and which granulation aids, fillers etc. are used.

For use, the commercially available concentrates are optionally diluted in a conventional manner, e.g. B. in wettable powders and emulsifiable concentrates using water. Dusty and granulated preparations and sprayable solutions are no longer diluted with other inert substances before use. With the external conditions such as temperature, humidity, etc. the required application rate varies. It can fluctuate within wide limits, e.g. B. between 0.1 and 10.0 kg / ha of active substance, but it is preferably between 0.1 and 5 kg / ha.

s wording examples

Example A:

An emulsifiable concentrate is obtained from 15 parts by weight of active ingredient

75 parts by weight of cyclohexanone as solvent and 10 parts by weight of oxyethylated nonylphenol (10 AeO) as emulsifier.

Example B

A wettable powder 15 easily dispersible in water is obtained by adding 25 parts by weight of active ingredient

64 parts by weight of kaolin-containing quartz as an inert substance, 10 parts by weight of lignosulfonic acid potassium and 1 part by weight of oleylmethyl tauric acid sodium as a wetting agent and 20 dispersing agent and mixed in a pin mill.

Example C

A dusting agent is obtained by adding 25 10 parts by weight of active ingredient and

Mixes 90 parts by weight of talc as an inert substance and crushes them in a hammer mill.

Example D

30 A granulate consists e.g. B. from about 2-15 parts by weight of active ingredient and 98-85 parts by weight of inert granule materials, such as

Attapulgite, pumice stone and quartz sand.

35 manufacturing examples

example 1

4- [4 '- (2 ", 4" -Dichlorophenoxy) -phenoxy] -valeric acid 20.3 g of 4- (2', 4'-dichlorophenoxy) -phenol are dissolved in 25 ml of absolute ethanol. 2.12 g of metallic 40 sodium are added and ethanol is distilled off after the sodium has dissolved. 10 g of y-valerolactone are then added to the solid 4- (2 ', 4'-dichlorophenoxy) phenol sodium and the mixture is heated at 210 ° C. for 24 hours. Hydrochloric acid and dissolves the residue in toluene. The toluene phase is extracted several times with saturated 45 t aqueous methanolic bicarbonate solution (50%). The combined extracts are concentrated with. Acidified hydrochloric acid and extracted with toluene. After the solvent has been stripped off in vacuo, 23.9 g = 80% of theory are obtained after recrystallization from cyclohexane. 4- [4 '- (2 ", 4" -Dichloipheno-5 ° xy) -phenoxy] -valeric acid, mp. 88 ° C.

The following are represented in the same way:

2. 4- [4 '- (4 "chlorophenoxy) phenoxy] valeric acid, 6® mp 65-66 ° C

3. 4- [4 '- (4 "-trifluoromethylphenoxy) phenoxy] valeric acid

Example 4

65 4- [4 '- (2 ", 4" -dichlorophenoxy) -phenoxy] -valeric acid-

butyl ester

25.9 g of 4- (2 ', 4'-dichlorophenoxy) phenol and 14.5 g of potassium carbonate in 150 ml of dimethylformamide are 1.5 hours

624 087

6

the heated under reflux. 20 g of 4-chloro-valeric acid butyl ester are then added dropwise at 80 ° C. and the mixture is heated to 120 ° C. for 12 hours. After the salt precipitate has been filtered off, the solvent is distilled off in vacuo. The oily residue is taken up in toluene, washed with dilute sodium hydroxide solution and water and dried.

After the toluene has been stripped off in vacuo, the residue is distilled under a fine vacuum.

32.1 g = 78% of theory are obtained. on 4- [4 '- (2 ", 4" -dichlorophenoxy) phenoxy] valeric acid butyl ester of Kp0 02 5 206 ° C.

Similarly, using 4-chlorovalero-nitrile:

5. 4- [4 '- (4 "-trifluoromethylphenoxy) phenoxy] valeronitrile

Example 6

4- [4 '- (2 ", 4" -dichlorophenoxy) -phenoxy] -valerianic acid-n-propyl ester 29 g 4- [4' - (2 ", 4" -dichlorophenoxy) -phenoxy] -valeric acid (from Example 1) with 30 ml of toluene and 12 g of thionyl

chloride heated to 60 ° C until gas evolution ceases. Then toluene and excess thionyl chloride are distilled off in vacuo. The remaining oil is taken up in toluene and added dropwise to a solution of 6 g of n-propanol and 20 8.5 g of triethylamine in 50 ml of toluene. After the addition, the mixture is stirred at 50 ° C. for 1 hour, then triethylamine hydrochloride is filtered off and washed with water. After the solvent has been stripped off, the mixture is distilled under high vacuum.

27.5 g of 4- [4 '- (2 ", 4" -dichlorophenoxy) -pheno-25 xy] -valeric acid n-propyl ester of Kp0j01 200 ° C. are obtained.

Example 7

4- [4'-Trifluoromethylphenoxy) phenoxy] valerian acid sec-butyl ester 29 g 4- [4 '- (4 "-trifluoromethylphenoxy) phenoxy] valerian acid, 1 ml concentrated sulfuric acid and 25 ml Butanol-2 is dissolved in 300 ml of chloroform and heated to the boil for about 2 to 4 hours until the separation of water has ended, after which it is washed neutral with saturated sodium bicarbonate solution and the solvent is distilled off in vacuo and the oily residue is distilled under a fine vacuum.

29.2 g = 87.5% of theory are obtained 4- [4 '- (4 "-trifluoromethylphenoxy) phenoxy] valeric acid sec-butyl ester of Kp0> 1 178 ° C.

Example 8

4- [4 '- (4 "-trifluoromethylphenoxy) -phenoxy] -pentanol-1 20.4 g of 4- [4' - (4" -trifluoromethyl- phenoxy) -phenoxy] -valeric acid isobutyl ester (from Example 7). After the addition is complete, the mixture is stirred under reflux for 1 hour. Then slowly first add 10 ml ss ethyl acetate, then 40 ml water, finally, with vigorous stirring, so much N — H2S04 until the precipitate of aluminum hydroxide is dissolved. The ether phase is washed neutral with sodium bicarbonate solution and the solvent is distilled off in vacuo. After distillation in a fine 60 vacuum, 15.4 g = 90.5% of theory on 4- [4 '- (4 "-Tri-fluoromethylphenoxy) -phenoxy] -pentanol-l of Kp0 07 174 ° C.

7

624 087

Example 9

1-chloroacetyloxy-4- [4 '- (4 "-trifluoromethylphenoxy) -phenoxy] -pentane To a solution of 17.0 g of 4- [4' - (4" -trifluoromethylphen-oxy) -phenoxy] -pentanol-l and 5.55 g of triethylamine in 60 ml of absolute toluene, 6.45 g of chloroacetyl chloride are added dropwise at room temperature. After addition, 1 hour at 50 ° C.

stirred, then the precipitate was filtered off, the toluene solution was washed with dilute hydrochloric acid and water and dried.

After the solvent has been stripped off, 18.5 g = 89% of theory l-chloroacetyloxy-4- [4 '- (4 "-trifluoromethylphenoxy) phenoxy] pentane.

ch3 o

-0-ch-choch2-CEj -o-c-ckgcl

The following were produced analogously:

10. l-Benzoyloxy-4- [4 '- (4 "-trifluoromethylphenoxy) phenoxy] pentane

11. l-Methylsulfonyloxy-4- [4 '- (4 "-TrifIuormethyl-phenoxy) -phenoxy] -pentane

12. 1-N, N-Dimethylcarbamoyloxy-4- [4 '- (4 "-trifluoromethylphenoxy) phenoxy] pentane.

To produce this compound, stirring is continued at 60 ° C. for about 10 hours.

20 Further compounds of the formula 1 obtainable according to the above examples are listed in the following table.

table

CHa

-0-CH-CH2-CH2-Z

Example No.

(R) n physics. Data shown after

example

13

14

15

16

17th

18th

19th

20th

21st

22

23

24th

25th

26

27th

28

29

30th

31

32

33

34

35

36

37

38

39

4-CF3

2,4-Cl2

4-C1

4-CF3

4-CF3

4-CF3

2,4-Cl2

2,4-Cl2

4-C1

4-CF3

4-CF3

4-CF3

4-C1

4-CF3

2,4-Cl2

4-CF3

4-CF3

4-CF3

4-CF3

4-CF3

4-CF3

4-CFa 4-CF3

4-CF,

4-CF,

4-CFa 4-CF3

-COOCH3 Kp02: 168 ° C

-COOCH3

-COOCH3

-COOC2H5

-COOC3H7 (n) Kp0.06: 169 ° C

—COOC3H7 (i)

-COOC2H5

-COOC3H7 (i)

-COOC3H7 (n)

—COOC8H17 (n)

-COOCH2CH2Cl

-COOCH (CH3) C2Hs

-COOCH2CH2OCH3

-COOCH2CH2OCH3

-COOCH2CH2OCH3

-COOCH2CH (CH3) 2 Kpo, 2: 187 ° C

-COOCH (CH2Cl) 2

-C00- (CH2CH20) 2C2H5

-COO (CH2) 2OCH2 (CH2) 2CH3

-conh2

-COO-CH

-Q

-cooch2ch2oh

-cooch2ch2sch3

-c co -c

-Cl

\ SC2 H5

-coo-ch2-ch = ch2

-COO-ch2-csch

4 4 4 6

6 6

6

7 7

6

7 7 6

6

7

6

7 7 6

624 087

Table (continued)

Example No.

(R).

physics. Data shown after

example

40

41

2,4-CI2

4-CF,

-C0-ÏÏH

-Cl

42

4-CF,

-C

• 0

43

44

45

46

47

4-CF3

4-CF3

2,4-Cl2

4-Br-2-Cl

4-Br-2-Cl

—COOMgl / 2 -COONH (C2H4OH) 3 -COOMgl / 2 -COOCH3

-COOCH2-CH (CH3) 2

4 7

Biological Examples Example I

Seeds of grass were sown in pots and the preparations according to the invention formulated as wettable powder were sprayed onto the surface of the earth in various dosages.

The pots were then placed in a greenhouse for 4 weeks. The result of the treatment (also 30 in the following examples as well) was determined by a bonus according to the Bolle scheme (newsletter of the German Plant Protection Service 16, 1964, 92-94):

Damage effect value in%

Weeds crops

1

100

0

2nd

97.5

to <100

> 0 to 2.5

3rd

95

to <97.5

> 2.5 to 5

4th

90

to <95

> 5 to 10

5

85

to <90

> 10 to 15

6

75

to <85

> 15 to 25

7

65

to <75

> 25 to 35

8th

32.5

to <65

> 35 to 37.5

9

0

to <32.5

> 67.5 to 100

The results of Table I show that the compounds have excellent herbicidal activity even in very low doses. They are the reference substances 2,4-DB and 2- [4 '- (2 ", 4" -Dibromphenoxy) -pheno-

50 xy] -propionic acid methyl ester is considerably superior both in terms of its range of action and because of its action at low doses.

Table I

Pre-emergence effect against harmful grass

Example No.

kg / ha A.S.

AV

AL

SET

PA

PT

LO

EC

1

2.5

6

4th

1

2nd

1

1

1

0.6

6

4th

1

3rd

2nd

1

2nd

0.15

8th

4th

1

5

2nd

2nd

3rd

6

2.5

4th

1

1

4th

1

1

1

0.6

5

1

1

7

2nd

2nd

1

0.15

6

4th

2nd

8th

5

5

2nd

AV: Avena; AL: Alopecurus; SET: Setaria; PA: Poa annua; PT: Poa trivialis; LO: lolium; EC: Echinochloa

9 624 087

Table I (continued) Pre-emergence effect against harmful grass

Example No.

kg / ha A.S.

AV

AL

SET

PA

PT

LO

EC

2,4-DB

2.5

8th

7

8th

5

4th

6

5

0.6

8th

8th

9

8th

6

8th

8th

0.15

9

9

9

9

9

9

9

2- [4 '- (2 ", 4" dibromphene-

2.5

8th

3rd

2nd

3rd

6

1

1

oxy) -phenoxy] -propion-

0.6

9

8th

8th

7

8th

5

2nd

acid methyl ester

0.15

9

9

8th

9

9

8th

6

AV: Avena; AL: Alopecurus; SET: Setaria; PA: Poa annua; PT: Poa trivialis; LO: lolium; EC: Echinochloa

Example II

In a further test, the effect of the compounds on crop plants was tested for the slightest damage to a large number of crop plants using the same test compounds, even in high dosages of 2.5 kg / ha. The values listed in Table II show that the different botanical families cause.

Table II Effect on crops

Compound from example 1 example 6

2.5 kg / ha 0.6 kg / ha 2.5 kg / ha 0.6 kg / ha

sugar beet

Sunflower

Rapeseed

pea

Soybean

Bush bean

Flax

Cotton tomato carrot cucumber

Claims (3)

624 087 2nd PATENT CLAIMS 1. Process for the preparation of a compound of Formula 1 tRl> n 0 ch- o-ch-ch2-ch2-z (I) wherein Ri halogen, -CF3 or (C1-C4) alkyl, Z the groups -CN, -CS-NH2, -CO-R2 or -ch2-o-r3, 15 R2 is hydroxy, -O-Kat, (C1-C12) alkoxy, which is optionally substituted by —OH, halogen, -CF3, (C! -C6) alkoxy, (C1-C4) alkylthio, phenyl, phenoxy or halophenoxy can be; Remains of the formulas -Oh 2 "S7 -Oh -OCHf ' "(0CoH,) 2 4 2-: OC Hn., -OC-H.-N m 2m + 1 ° A 2 4 - (C ^ -C ^) alkyl V (C1 ~ C4) alkyl -OC2H4-N A, wherein -N a 35 Kat the cation equivalent of an inorganic or organic base, n is a number from 1 to 3 and m is a number from 1 to 6, characterized in that a substituted phenoxy-40 phenol of the formula II represents the pyrrolidinyl, piperidinyl, morpholinyl or N-methyl-piperazinyl radical; (C5-C6) cycloalkyl, which may optionally be substituted by (Ci-C4) alkyl and / or halogen; (C3-C4) alkenyloxy, cyclohexenyloxy, (C3-C4) alkynyloxy, which may optionally be substituted in the 1-position by (Cj-C4) alkyl and / or phenyl; Phenoxy, which may optionally be substituted by halogen, -N02 and / or (Ci-C4) -alkyl; (C1-C6) alkylthio, allylthio, phenylthio, halogenophenylthio, amino, (C1- ^ C4) alkylamino, hydroxyethylamino, di- (C1-C4) alkylamino, pyrrolidino, piperidino, morpholino; Anilino, which may optionally be substituted by halogen, -CF3 and / or (Q-G ^ -alkyl), and hydrazino, R3 is hydrogen, (C! -C4) -alkyl, (Ci-Q) -alkylcarbonyl, halogen (C1-C4) -alkylcarbonyl, benzoyl, which is optionally substituted by halogen, -N02 and / or (Cj-C ^ -alkyl) ; (C1-C4) alkylcarbamoyl, di- (C1-C4) alkylcarbamoyl, phenylcarbamoyl, which may optionally be substituted by halogen and / or (Q-Qj-alkyl); (C1-C4) alkylsulfonyl, phenylsulfonyl, -S03H or -S03Kat. As well 45 (ii) 50 with a y-valeric acid derivative of the formula III CH3 I Y-CH-CH2CH2Z (Hi), where Y is halogen, converts to 5J under basic conditions and, if appropriate, the compound obtained is converted into a salt. 2. Use of the compounds of formula I, prepared by the process according to claim I, as an active component in herbicidal compositions. 3. Process for the preparation of a compound of formula Yes 624 087 wherein Ri halogen, -CF3 or (Ci-C4) alkyl, Kat the cation equivalent of an inorganic or organic base, R2 hydroxyl, -O-Kat, (QC ^ J-alkoxy, which may optionally be substituted by -OH, halogen, -CF3, (C1-C6) alkoxy, (Ci-C4) alkylthio, phenyl, phenoxy or halophenoxy ; Remains of the formulas -Oh 2 \ ■ OCH. O -OCH ~ (° C2H4) 2-3 ° CmH2m + 1 ' -OC-H.-N A, 2nd h \ ' • (C ^ -C ^) alkyl (C- | -C ^ j) alkyl wherein -N 25th (C1-C3) alkyl may be substituted; (C1-C4) alkylsulfonyl, phenylsulfonyl, -S03H or -S03Kat. and n is a number from 1 to 3 and m is a number from 1 to 6, characterized in that substituted phenoxyphenols of the formula II represents the pyrrolidinyl, piperidinyl, morpholinyl or N-methyl-piperazinyl radical; (QC ^ -cycloalkyl, which may optionally be substituted by (Ci-C4) -alkyl and / or halogen; (C3-C4) -alkenyloxy, cyclohexenyloxy, (C3-C4) -alkynyloxy, which may be in the 1-position can be substituted by (Ci-C4) -alkyl and / or phenyl; phenoxy, which can optionally be substituted by halogen, NO2 and / or (C1-C4) -alkyl; (C1-C6) -alkylthio, allylthio, phenylthio, Ha-logenphenylthio, amino, (C1-C4) alkylamino, hydroxyethylamino, di (Ci-C4) alkylamino, pyrrolidino, piperidino, morpholino; anilino, which may be replaced by halogen, -CF3 and / or (QC ^ -Alkyl can be substituted, and hydra-zino, R3 is hydrogen, (Cj-C4) alkyl, (Cj-G ^ -alkylcarbonyl, halogen (C! -C4) alkylcarbonyl, benzoyl, which is optionally substituted by halogen, -Nü2 and / or (C1-C4) -alkyl ; (Ci-C4) -alkylcarbamoyl, di- (C1-C4) -alkylcarbamoyl, phenyl-carbamoyl, optionally by halogen and / or 30th (R-,) In 0 Oh (ii) 35 with y-valerolactone of formula IV 40 (IV) reacted under basic conditions and the compound obtained optionally converted into the free acid. 45 4. Use of the compounds of formula Ia, prepared by the process according to claim 3, as an active component in herbicidal compositions. In DE-PS 1 668 896 and 2 136 828 and DE-OSn 2 223 894 and 2 433 067 phenoxy-phenoxy-propionsäu-rederivate with halogen, CF3 and alkyl substitution in the terminal phenol ring and herbicidal compositions based on these compounds described.