DE2248800A1 - HERBICIDAL AGENTS - Google Patents

Description

The present invention relates to use of ^ -chlorobenzyl-NjN-hexamethylene thiol carbamate as herbiside.

To combat chicken millet, a weed

which occurs in rice fields was previously pentachlorophenol (PCP) is used. However, since this connection causes extreme heating of the human mucous membranes, it is extraordinary is toxic for fish and difficult to dose, application time and area of application are severely limited.

To control swamp rush and broad-leaved weeds that grow in the same season as barnyard millet, was previously 2-methyl-4-chlorophenoxyacetic acid (MOP) used. However, this compound is not very effective for fighting barnacles.

Nit 101 , -1-

309817/1186

For this reason, a mixture of PCP and MCP has so far been used to control chicken hj, rse, Marsh rush and broad-leaved weeds used in rice fields. U.S. Patent No. 3,224,861 goes show that thiol and dithio-carbamic acid esters of general formula

X ·

η R-X-C-

in which

X and X ^{1 represent} oxygen or sulfur, but at least one of the radicals must represent sulfur and R represents a benzyl radical optionally substituted by up to k halogen atoms, show herbicidal activity.

It has now been found that 4-chlorobenzyl ~ N, N-hexamethylene thiol carbamate, a connection which is not mentioned in detail in the above-mentioned USA patent specification, extraordinary has herbicidal properties.

The aim of the invention is therefore a method for combating weeds, which is characterized in that 4-chlorobenzyl-N _t N-hexamethylene thiol carbamate of the formula is applied to weeds or their habitat

(I)

alone or in a mixture with diluents or carriers can act.

According to the invention, harvests are obtained which are resistant to damage were protected by weeds in that they were grown in areas immediately before and or during the growth period with a compound of the formula I, alone or in admixture with a diluent or carrier, were treated.

The compound of formula I can be prepared

Nit 101 -2-

3 0 9 8 1 7 / Π 8 5

22A880Ü

be by one

(a) 4-chlorobenzyl mercaptan of the formula

Cl- / V ^CH 2 " ^SH

in the form of an alkali metal salt, or in the presence of an acid binder with Ν, Ν-hexamethylenecarbanioylchloride the formula

Cl-C-N Hj, '(Hl)

implements, or

(b) a 4-chlorobenzylyide halide of the general formula

\ cH ₂ -Hal, (IV)

in which

Hai stands for halogen,

with carbon oxysulphide and Ν, Ν-hexamethyleneimine formula

ΗΝ 'HJ _s (V)

from

in the presence of an alkali metal hydroxide or ammonium hydroxide.

Process variant a) is preferred in the presence carried out by inert organic solvents, such as aliphatic or aromatic hydrocarbons, which may optionally be halogenated, such as gasoline, methylene chloride, chloroform, carbon tetrachloride, benzene, Chlorobenzene, toluene or xylene; Ethers such as diethyl ether, dibutyl ether, dioxane or tetrahydrofuran; low boiling Alcohols such as methanol, ethanol or isopropanol; Ketones, such as acetone, methyl ethyl ketone, methyl isopropyl ketone or Methyl isobutyl ketone; or lower aliphatic nitriles such as acetonitrile or propionitrile.

Nit 101 -3-

3 η 9 8 1 7/1 1 8 5

Alkali metal carbonates or bicarbonates, such as sodium bicarbonate, potassium carbonate, can be used as acid-binding agents or sodium carbonate; Alkali metal alcoholates, such as potassium or Nfi trium methylate or ethylate; or aliphatic, aromatic or heterocyclic tertiary bases such as triethylamine, diethylaniline or pyridine can be used.

Process variant a) can be explained in more detail using the following equation:

f / \ ι

f / \ ι

-C-NH

2 ^ x

CH ₀ -SCN H] + H Cl

² y

In the formulas it says
M for hydrogen or an alkali metal.

Process variant b) can also be used in the presence of inert organic solvents, as already described under process variant a), in particular however, alcohols, ketones or even water can be carried out.

Process variant b) can be described in more detail using the following formula scheme:

s— - \

+ M ² .OH

H ₂ O

being in the formulas

Hai stands for halogen, and

M stands for an alkali metal (such as sodium or potassium) or the ammonium radical.

As already mentioned, the active ingredient according to the invention was not described in detail in some of the USA patent specification (bfii, but it shows, in contrast to the

N JtI Q] -i | -

: i 0 9 B 1 7/1 1 H B

Patent disclosed compounds, and the m the U.S. Patent No. 3,303,014 described benzyl-N, N-hexamethylene thiol carbamate, which has a similar structure, surprisingly not only excellent herbicides Effectiveness against various rice field weeds such as chicken millet, swamp rush and broad-leaved weeds, but also shows only low phytotoxicity in rice plants, which enables their extensive use. The active ingredient according to the invention is therefore of great practical importance.

To date, to control rice field weeds, in particular barnyard millet, it has generally proven necessary to apply herbicides to the rice fields k up to 8 days after the rice plants have set in, ie before driving out the chicken millet or during the 0-1.5 leaf Stage, as the resistance of the barnyard to herbicides generally increases during the growing season. It was further observed that the rice plants exhibited phytotoxicity when the rice plants were treated with known herbicides before the planting or before the sprouting of the barnyard millet. The prior art herbicidal compositions were effective in controlling barnyardgrass only when applied after the rice plants were planted and during the early stages of growth of barley grass. For this reason, the treatment had to be repeated very often to obtain the control weeds growing at a later time. There has therefore been a real need for a herbicide with a long application period by means of which considerable labor savings could be achieved.

fin. '

The compounds of formula I show excellent

and selective herbicidal activity not only against aquatic weeds, especially barnyard millet from the Family of the Gramineae and perennial weeds like Swamp rush, but also against broad-leaved weeds, against which the herbicides known to date have little effect

Nit 101 -5-

30981-7 / 1,186

was. The active ingredient according to the invention also shows none Phytotoxicity in rice plants, and thus proves itself as an exceptionally good herbicide with an extended application period starting with the time before sprouting the chicken millet (before the rice plants are planted) and continuously until the 2-3 leaf stage of the weeds (10 to 15 days after planting the rice plants).

The active ingredient according to the invention is therefore characterized due to its pronounced herbicidal effectiveness not only when used before driving out the barnyard millet, but also when it reaches the 2-3 leaf stage of the weed is used in flood conditions. Since it also shows no phytotoxicity in rice plants, can he at any time during the extended period of use with full effectiveness and safety be applied.

This is particularly advantageous due to the fact that most of the commercially available herbicides are effective only before or immediately after the development of the barnyardgrass. Show further other known substituted benzylthiol carbamic acid esters generally have insufficient effectiveness against broad-leaved weeds. As already mentioned, the inventive Active ingredient characterized by its excellent effectiveness in combating such weeds. In addition, the active ingredient according to the invention can due to its low phytotoxicity in rice plants can be used to control such aquatic weeds, and brings furthermore, a considerable saving of labor, since it is of the time before the planting of the rice plants until one or two weeks after the onset can be applied, i.e. a period for which no Control method was generally known.

The active ingredients according to the invention can be converted into the customary formulations, such as e.g. Solutions, emulsions, slurries. Powder, pastes, gra-

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: i 09817/1185

nulate tmd aerosols. The formulations can be based on in and of themselves be prepared in a known manner, e.g. by mixing the active ingredient with an extender !!, i.e. with liquid, solid or liquefied gaseous diluents or carriers, optionally using surface-active agents Agents, i.e. emulsifiers and / or dispersants. If water is used as an extender, see above For example, organic solvents can be used as solubilizers.

Examples of liquid diluents or carriers are preferably aromatic hydrocarbons, such as xylene, toluene, benzene, or alkylnaphthalenes; chlorinated aromatic or aliphatic hydrocarbons such as chlorobenzenes, chloroethylenes or methylene chloride; aliphatic hydrocarbons such as cyclohexane; or paraffins, e.g., petroleum fractions; Alcohols such as butanol or glycol and their ethers and esters; Ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone or cyclohexanone; or strongly polar solvents, e.g. Dimethylformamide, dimethyl sulfoxide or acetonitrile and Called water.

Liquefied gaseous diluents or carriers are to be understood as meaning liquids which gaseous under normal temperatures and pressures such as propellants for aerosols, such as halogenicrte Hydrocarbons, e.g. freon.

As a permanent diluent or carrier, the powders of natural inineralis have been preferred Substances such as kaolin, clay, IaIk, chalk, quartz, atiapulgite, Montmorillonite or diatomaceous earth, or the synthetic powders _miiierali shear substances, such as highly dispersed silica, aluminum oxide or silicates, used

Among the bevorztigten examples of emulsifiers, such as Polyoxyäthylenf et t acid 1 there he Polyoxyathylenfe-ti - alcohol ether, eg Alkylarylpolyßlylfoläiher, alkyl,

Alkyl sulfates and aryl sulfonates | preferred dispersants * ) include jiicliiionogeiui and ani onis <; he L'mulgai oren

Ni t 101 ~ 7 ~

OiUi 1 7/1 1 B

224880Q I.

are lignin, sulphite waste liquors and methyl cellulose.

The amount of active ingredient in the formulations is generally 0.1 to 95 ow.-ji, preferably 0.5 to 90 wt .- $.

If required, the active compounds according to the invention can along with other agricultural chemicals, such as e.g. insecticides, acaricides, nematocides, antivirals, fungicides, herbicides, plant growth regulators, Fertilizers and optionally other known auxiliary substances can be used.

The ready preparations (which may be made of suitable formulations, for example by dilution with water) can be used in a conventional manner, be such as by spraying liquids, misting, atomizing, dusting, scattering, watering, heaping, fill with smoke, soil treatment, such as Mixing, sprinkling, steaming and sprinkling, surface treatment such as painting, applying strips, covering the surface with dust or dipping.

The amount of active ingredient in the ready-to-use preparations is usually between 0.001 and 10% by weight, preferably between 0.005 and 5% by weight. The active ingredient content may vary depending on the type of preparation used, process, purpose, time and place of application and the stage of growth the weeds to be controlled can be varied.

The compounds of the invention can be used, which Wirkatoffkonzentratlonen of up to 95 ° and 100 ° / o permitted according to the known ultra-low-volume method.

The dosage amount per unit area is in generally between 0.5 and 20 kg, preferably 1 to 10 kg of active ingredient per ha. These amounts of active ingredient can be according to Needs to be exceeded or not reached.

The preparation of the compound of the formula I will be explained in more detail with the aid of the following examples will. ,

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3 09817/1185

Example 1:

To a solution of 7.9 g (o, O5 mol) of 4-chloro-> benzylmercaptan in I50 ml of acetone was added 4g of an HO? B-aqueous solution of NaOH zngefcropft. The sodium formed - ^ - Chlorbenzylmercaptid was slowly ö »1 S (0.05 mol) NJN-Hexamethylencarbamoylchlorid under stirring at room temperature was added dropwise. The mixture was then refluxed for 3-4 hours, the acetone was distilled off, and crude crystals were separated out by adding cold water. After recrystallization of the crude product from ethanol, 11.4 g of 4-chlorobenzyl-Ν, Ν-hexamethylene thiol carbamate were obtained in the form of white crystals. Yield: 80.2% . M.p .: 59-60 ° C.

Example 2:

30 ml of water were added to 15 g (o.15 mole) of N, N-hexamethyleneimine in a 200 ml three-necked flask, 20 g (0.125 mol) of a 25 ° / o ± gen aqueous NaQH solution was added, and under constant Stirring cooled to 0 - 5 C «

In a gas generator, 30 ml of a saturated Ammonium thiocyanate solution to a sulfuric acid solution consisting of 145 ml of sulfuric acid and 200 ml of water slowly given with stirring at 20 ° C. The formed carbon oxysulfide was poured into the three-necked flask with continued stirring initiated.

After 1-2 hours, the temperature in the gas generator had risen to about 50 ° C. and the reaction was almost complete, ie about 10 g (0.17 mol) of carbon ns toffoxysulfid had been introduced into the flask. After the end of the introduction, 16 g (0.1 mol) of 4-chlorobenzyl chloride were added in one portion to the flask, and the resulting mixture was stirred at 0-5 ° C. for one hour and then at 20-4o ° C. for a further k hours. After filtration, 25 g of the product were obtained in the form of white crystals.
Yield: 90 # Mp .: 59-60 ° C

Nit 101 _9_

3 0 9 8 17/1185

λα

Below are some example formulations described in more detail which contain the compound of formula I as active ingredient. Parts and ^ figures are Parts by weight and wt .- ^.

Example (i);

5 parts of active ingredient and 95 parts of a mixture of talc and clay are ground and made into a dust mixed.

Example (il):

20 parts of active ingredient, 75 parts of a mixture of zeeklite and clay, 3 parts of a sodium salt of an alkylbenzenesulfonic acid and 2 parts of sodium dinaphthyl methane disulphonate are ground together to form a wettable powder.

Example (iii):

20 parts of active ingredient, 75 parts of xylene and 5 parts "Sorpol" (emulsifier) become an emulsifiable concentrate stirred, which was diluted with water before application.

Example f iv);

The active ingredient was dissolved in xylene with heating and sprayed onto granular clay. The granules obtained, which contained about 10 % active ingredient, were scattered directly onto the surface of the earth.

The herbicidal activity of the compound of the formula I is demonstrated by the application examples below illustrated in more detail.

Example A: Test against rice field weeds under flood conditions; Soil treatment

Preparation of the formulation base ι

Solvent: 5 parts by weight of acetone Emulsifier: 1 part by weight of benzyloxy polyglycol ether

1 part by weight of active ingredient and the above-mentioned amounts of emulsifier and solvent become an emulsifiable one Concentrate mixed together, which was diluted with water to the desired concentration.

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3 0 9 8 17/1185

Test procedure:

Plastic pots with a diameter of 28 cm were filled with sieved rice field soil and flooded to a height of 2 cm. The prescribed amount of the active ingredient was added dropwise with a pipette using the emulsion described above, and then mixed into the soil to a depth of 15 cm, whereby an even distribution was achieved. Now more soil, which contained millet seeds and seeds of other common rice field weeds in large quantities, was added to a depth of 2 cm from the surface of the earth. Thereafter, two rice seedlings (Var. Kinmaze) in the 2-leaf stage per pot were placed in the middle of the surface of the earth, and finally 2 × 2 cm pieces of rushes were planted in the surface of the earth. The soil was flooded to a height of 3 cm, and the herbicidal effectiveness and phytotoxicity were determined after h weeks, and evaluated on the following scale:

Herbicidal effectiveness - comparison with untreated control area

5: over 95 ° / o destroying

ki over 80 to 95 per cent. extinction

3: over 50 to 80 ^c / o eradication

2: over 30 to 50 # extinction

1: over 10 to 30 ^c / o eradication

0: less than 10 % eradication

Phytotoxicity in rice plants - comparison with untreated control area:

5: over 90 % damage

k: over 50 to 90 % damage

3: over 30 to 50 ° ß> damage

2: 10 to 30 $ damage

1: less than 10 % damage

0: no damage (no phytotoxicity)

• The results are shown in Table A:

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3 0 9 8 17/1185

Table A. Test against rice field xin herbs under flood conditions

Compound herbicidal effectiveness

Really Chicken umbrella 5 material millet reed VJl (g / lOa) grass VJl 400 VJl 4th 200 5 3 100 4th .0 2000 *
3 5 1500 1 4th 1000 0 3 1500 4th 1000 3-4 500 3

swamp
bull broadbl.
Weeds
ter Phytotoxic
ity at
Rice plants 5 5 0 4th VJl 0 3 4th 0 3 0 1 2 0 0 0 0 0 3 3 VJl 2 1 5 0 0 4th

O CO OO

^) - CH ₂ -SCN HJ

(compare ITo. 1) 0

j - \ "/ N

U M-CH ₅ -SCN H

(Comparison No. 2)

Nit

-12-

Table A. Test rain Rice field unlci'äuter underneath
(Continuation) Chicken
millet About the inhibition conditions swamp
bull 3 broadbl.
Weeds
ter Phytotoxi ^v -
ity at
Rice plants Really
material
(g / lOa) 4th Herbicidal effectiveness 3 0 4th ■ 4 link 1500 3
0 umbrella
reed
grass CVJ O 0 3
1 3
2 • ^C1 "J 1000
500 5 4th 3 . 3 . 5 ^^ - cH ₂ -sc-ir η]
(Comparison no.3) 1500 3-4 3
1 CVJ 0 3 4th co
CD
CO
OD Cl 0 1000 3 5 1 1 ³ .... Ϊ -J 500 4th vz / ² v_y 4th 3 4th 5 co
Cn (Comparison no. K) I5OO '3-4 2 2-3 Qi ci 0
A ~ \ C "/ —N 1000 ViJ "4 1 5 500 3 0 0 0 0 (Comparison No. 5) Untreated '
Control area 0

Nit 101

-13-

Remarks; L. Common-leaved weeds: Monochoria,

Ilotala indica and Lindernia pyxidaria;

2. Comparison compounds: No. 1, 3 and 5 U.S. Patent No. 3,224,861;

3. Comparative compound no. 2: U.S. Patent No. 3,303.0A;

Example B: Pre-emergence test against rice field weeds under flood conditions; Water treatment before the rice seedlings are set.

Wagner pots with a surface area of 1/500 a were filled with sieved rice field soil and mixed with further soil containing large quantities of millet seeds and other seeds of common rice field weeds to a depth of 2 cm from the surface of the earth. Then 2x2 cm pieces of the marsh rush were inserted into the surface of the earth and flooded to a height of k cm.

The active ingredient was in the form of the formulation given in Example A using a pipette in the prescribed Amount added dropwise. After 30 minutes, rice seedlings (Var. Kinmaze) in the 2-leaf stage were in the middle of the earth's surface planted, and the flood water with peeled off at a rate of 2 cm per day for 2 days, and then held at a height of 3 cm.

After k weeks, the herbicidal activity against the weeds and the phytotoxicity according to the type described in Example A were determined. The results are shown in Table B.

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3 09817/1185

Table B; Pre-emergence test against dark rice fields under flood conditions. Water treatment before the rice seedlings are set

link

CD
CXJ

Herbicidal effectiveness

Active chicken umbrella fabric millet ried (g / lOa) grass

• 300

150

75

(D

^ / \\ - CH ₂ -SC-IiEj ₁₀₀₀

^ ~~ ^ 500

(Comparison No. l)

_/ ^ -v 600

-CK ₂ -SCN KJ 300

\ - '150

(Comparison No. 2)

5
5
5

5
4th
3

5 5 5

4 4 0

4 4 3

swamp broadbl. 5 Phytotoxi "- bull Weeds ■ 5 quote at ter 5 Rice plants 4-5 3 0 4-5 0 0 4th 0 0 3 4th 2 0. 2 1 0 0 0 3. 5 2 4th 0 3 "

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Table R: Pre-mergence test against rice field weeds under flood conditions: water treatment before the rice seedlings are set

link

Active ingredient

Herbicidal effectiveness

Rush

Cl

^ VcH ₂ -SCN HJ
(Comparison No. 3)

600 300 150

600 300 150

(Comparison No. 5)
Untreated

Nit 101

Chicken- umbrella millet reed grass 4th 4th 2 2 0 0

4th
3
0

4th
3
1

broad, phytotoxic weed at ter Rois Pflanzen

2
0
0

3
0
0

1
0

1
0

3
2
0

3-4
2
0

4 2 0

4 2 1

3 2 0

-16-

Aumei'kung: Broad-leaved weeds: Monochoria,

Rotala indica and Lindernia pyxidaria

Example C; Pre-emergence test against rice field weeds

under flooding conditions. treatment after planting the rice seedlings.

2 rice seedlings each (Var. Kinmaze) in the 2-leaf stage (about 10 cm high) were placed in Wagner pots with a surface area of 1/5000 a, which were filled with rice field soil were planted, and with more soil containing large quantities of millet seeds and seeds of others Contained rice field weeds to a depth of 2 cm evenly mixed by the surface of the earth. Then 2x2- cm pieces of the swamp rush were planted in the earth, and flooded the pots to a height of 3 cm. The active ingredient was in the form of that described in Example A. The prescribed amount of emulsion was added by means of a pipette shortly after the rice plants were planted, and drained the flood water for 2 days at a rate of 2-3 cm per day, and then kept at a height of about 3 cm.

Herbicidal activity and phytotoxicity were determined in the manner indicated in Example A after h weeks. The results are shown in Table C.

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309817/1185

Table C: Pre-emergence test against rice field weeds under flood conditions. Treatment after planting the rice kit tongue

link

Active ingredient (g / 10a) Herbicidal effectiveness

Chickens millet

Schirmried grass swamp rush

broadbl.
Weeds

Phytotoxicity
Rice plants

O (D OO

300

150

75

5 5 5

5 5 5 .

4-5 4th

5 5

^s / ~ N

(Comparison No. l)

1500

1000

500

2-3 0

3-4 3 0

0 0

3 0 0

(Compare Ko. 2)

600 5 4th 3 300 3-4 3 1 150 3 2 0

4th
2
0

Nit IQl

-18-

Table C; Pre-emergence test against rice field weeds under flood conditions. Treatment after planting the rice seedlings

^ Continued)

""binding

Cl

fi \

CH ₂ -SCN H

{Compare No.3)

Herbicidal effectiveness

Active ingredient (g / lOa)

Chicken millet

600 300 150

Umbrella grass

Rush

3-4 2 0

breitbl, phytotoxic-Unkräuzität in ter rice plants

3
1
0

3 1 0

CH ₂ -SCK H

(Comparison No. * 0

Gl pl

CH ₂ -SCN H

("Comparison No ₀ 5)
Originally treated

600 300 150

600 4th 300 2 150 1

4 3 0

4 3

3
2

4th
2
0

2 0 0

2 1 0

GO OO CD

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-19-

Remarks; Broad-leaved weeds! , Monochorla, Rotala indica and Lindernia pyxidaria

Example D: Post-emergence test against rice field weeds

under flood conditions; Water treatment.

2 rice seedlings each (Var. Kinmaze) in the 2-leaf stage (about 10 cm high) were in Wagner-Töpf6 by I / 5OOO a surface, which is filled with rice field soil were, planted, and with further soil, which Contained large quantities of millet seeds and seeds of other common rice field weeds to a depth from 2 cm from the surface of the earth evenly mixed. Then 2x2 cm pieces of the rush were put into the earth planted, and the pots in moist conditions stored. After the chicken millet had reached the 2-3 leaf stage (10 days after the seeds were set), the pots were flooded to a height of 6 cm, and the active ingredient in the form of that described in Example A. The prescribed amount of emulsion is applied using a pipette.

After the treatment, the flood water became at a rate of 2-3 cm per day about

Subtracted 2 days, and then at a height of about

3 cm held.

After k weeks, herbicidal effectiveness and phytotoxicity were determined in the manner described in Example A.
established.

The results are shown in Table D »

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309817/1185

Table D: Post-emergence test against rice field weeds under flood conditions; VasSer treatment

link

Herbicidal effectiveness

Really
material
(g / 10a). Chicken
millet umbrella
reed
grass swamp
bull broadbl.
Weeds
ter Phytotoxic
ity at
Rice plants 400
200
100 5
5
4-5 5
5
/ 4-5 4-5
4-5
4th 5
5
4-5 OOO Ί500
1000 3
0
0 1
0
0 ooo 3
1
0 ooo

CjO O CO OO

0 _/ ^ -v

ti '■ l

(Comparison No. l)

800 4th 3 0 3-4 4th 500 2 1 0 2 4th 200 0 0 0 0 - 2

(Comparison No.2)

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-21-

go ω ο

Table D: Post-emergence test against rice field weeds Herbicides under flood (Continuation) Phytotoxic
quote at
Rice plants conditions; Water treatment umbrella
reed
grass broadbl.
Weeds
ter link Active chicken
millet fabric
(e / ioa) Effective Coit swamp
bull

• 5 's.

CH ₂ -SCN HJ

(Comparison No.3)
.Cl- ₀

, —D— \ * - si α. ι

(Comparison No. k)
CX ' Cl

CH.

- ^ Λ

, -S-C-H η)

(Comparison No.5) Untreated

Nit 101

2
0
0

3-4
2
1

3
2
0

0 0

3 2 0

2 1 0

1 0 0

0 0 0

0 0 0

0-1

3-4 2 0

4 2 0

Kp

-22-

Remarks; Broad-leaved weeds: Monochoria, Rotala indica and Lindernia pyxidaria

Example E; Test against rice field weeds under flood conditions; Soil treatment,

A concrete vessel 50 cm long, 50 cm wide and 30 cm height was used for this test.

A 3 cm high layer of otter, a 2 cm

A layer of sand and a 3 cm layer of rice field do were placed in the vessel one after the other and lightly pressed. Then it was filled up with sieved rice field soil to a height of 10 cm, and watered to a depth of about 2 cm. The active ingredient was sprinkled with the prescribed amount of a granulate prepared according to example (iv), and intimately mixed with the soil to a depth of 10 cm. Then further soil, which contained large quantities of millet seeds and seeds of other rice field weeds, was mixed up to a depth of 2 cm from the surface of the earth, and 2 rice seedlings (Var. Kinmaze) in the 2-leaf stage were planted in k different areas of the soil, and 2x2 cm pieces of the swamp rush inserted into the surface of the earth. The vessel was flooded to a height of h cm, and the flooding water was drained for 2 days at a rate of 2 cm per day, after which it was kept at a height of 3 cm. After h weeks, herbicidal activity and phytotoxicity according to the type listed in Example A were determined. The results are shown in Table E.

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3 0 9 8 1 7/1 1 8 p

Table E: Test against rice field weeds under flood conditions; Soil treatment

link

Active ingredient (g / lOa)

Chickens, millet

Herbicidal effectiveness

Schirmried
he as

Rush

broadbl. Phytotoxic Unkräu- zitüt in ter rice plants

/ ~ \ -CH ₂ -SCN

(Comparison No.2)

'600 400 200

1000 750-500

5 5 4

3 3 2

5
5
4th

0
0
0

5 5 5

2 0 0

0 0 0

4 4 3

(Comparison No.6)

5 3 1

4-5
3
2

4 2 Q

2 0 0

Nit 101

Table E: Test against rice field weeds under flood conditions; Soil treatment

(Continuation)

link

Active ingredient (g / 10a).

Herbicidal effectiveness

Chicken millet

Umbrella sedge

Rush

broadbl. Phytotoxi "impurity ter rice plants

(Comparison No. "7)

Untreated11 e
Control area

600 400 200

5 2 0

4 3 0

3 0 0

3 3 0

3 1 0

Remarks; 1. Broad-leaved weeds; Monochoria, Rotala indica and Lindernia pyxidaria.

2 _e Comparison No, 6, 4-chlorobenzyl-N, N-diethylthiocarbamate (trade name "Satan").

3 «Comparison No. 7, 2, k-dichlorophenyl-V-nitrophenyl ether (Trade name "Nippu").

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- it-

Example F; Pre-emergence test against rice field weeds

under flood conditions before planting the rice seedlings; WasSer treatment.

As described in Example E, a vessel was filled with crushed stone, sand and earth and topped up to a height of 10 cm with sieved rice field soil. This layer of soil was then mixed to a depth of 2 cm with further soil containing large amounts of millet seeds and seeds of other common rice field weeds, after which 2 × 2 cm pieces of the rush were used. It was flooded to a depth of about k cm and the active ingredient was applied as described in Example E. After one hour, two rice seedlings (Var. Kinmaze) in the 2-leaf stage were planted in four different areas of the soil, and the flood water was removed for 2 days at a rate of 2 cm per day, after which it was kept at a depth of about 3 cm .

After k weeks, herbicidal activity and phytotoxicity were determined analogously to Example A. The results are shown in Table F.

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Table F; Pre-dergence test against rice field weeds under overwhelming conditions before planting the rice seedlings; ¥ asSer treatment

link

Really
material '
(g / 10a). Chicken
millet umbrella
reed
grass 300
150
75 UMfMfV 5
5
5 600
400
200 5
3
2 4th
4th
3 300
150
75 5
\ 5
5
3

Herbicidal effectiveness

Rush

broadbl. Phytotoxi * - weeds ter rice plant

OJ
O
CO
OO

It

(D

CK ₂ -SCN H

(I compare "~ No. 2)

4-5 4 3

3-4 2 0

4 3 2

5 5 5

4 3 1

0 0 0

5 4 3

1 0 0

(Comparison No.6)

(Comparison No.'7)

Untreated 11 e control area Nit 101

400 200 100

3-4 0

3 2 0

5 4 0

-ο

2-3 0

-27-

Notes: Broad-leaved weeds: Honochoria, Rotala indica and Lindernia pyxidaria

Example G: pre-emergence test against rice field unfitter under flood conditions after planting the rice seedlings; - water treatment,

As described in Example E, a vessel was filled with crushed stone, sand and earth, to a height of 10 a filled with sieved rice field soil, and to a depth of 2 cm from the surface of the earth with further soil, which © large Containing quantities of millet seeds and seeds of other common rice field weeds, mixed. After that, 2 χ 2 cm Pieces of rush planted, and 2 rice seedlings (Var. Kinmaze) each in the 2-leaf stage in four different ones Areas of the ground used. Immediately thereafter, the active ingredient was applied as described in Example E, and the flood water is drained for 2 days at a rate of 2 cm per day, after which it is on a depth of 3 cm.

After k weeks, the herbicidal activity and phytotoxicity were determined analogously to Example A. The results are shown in Table G.

Jit IQl -28-

17/1135

Table C: Pre-emergence test against rice field weeds under flood conditions before planting the rice seedlings; Water treatment

O CD CO

link

Herbicidal effectiveness

Cl-T VCH ₂ -SCN H

(I)

₂ -SCN H

(Comparison No. 2.) O

(Comparison No.6)

' ^C1

(Comparison No.7) Unbeh. ^N control surface nit

Really
material
(g / 10a). Chicken
millet Schxrm-
reed-
grass 300
150
75 . 5
5
5 mintn
• 600
400
200 . .5
3-4
........ A ■ 4-5
4th
3 300
150
75 5
4th
3 5
5
4th 400
200
100 5
3-4
0 5
5
0

swamp
bull brcitbl.
Weeds
ter Phytotoxic
zitiit at
Rice plants 5
4th
3 m in in 000 · 3-4
3
2 3
1
0 5
4th
3 4-5
4th
3 4-5
3
1 0 /
0
0 4th
2
0 5
4th
0 4th
1-2
0

-29-

22 * 9800

Remarks; Broad-leaved weeds: Monochoria »Rotala indica and Lindernia pyxidaria

Example H: Post-emergence test against rice field weeds under flood conditions; Water treatment.

As described in Example E, a vessel was filled with crushed stone, sand and earth, sifted rice field soil was filled to a height of 10 cm, and to a depth of 2 cm from the surface of the earth with further soil containing large quantities of millet seeds and other common seeds Contained rice field weeds, mixed. Thereafter, 2 × 2 cm pieces of the marsh rush were planted, and 2 rice seedlings (Var. Kinmaze) in the 2-leaf stage were placed in four different areas of the ground. After 10 days, when the chicken millet had reached the 2-leaf stage, the active ingredient was applied analogously to Example E, and the flood water was drawn off immediately afterwards at a rate of 3 cm per day for two days, after which it was kept at a depth of k cm .

After four weeks, the herbicidal activity and phytotoxicity were determined analogously to Example A. The results are shown in Table H.

Nit 101 -30-

309817/1185

Table H; Post-emergence test against rice field weeds under flood conditions; Water treatment

Ye! 'Bond

Herbicidal effectiveness

Active chicken umbrella fabric millet ried (g / lOa). grass

swamp
bull broadbl.
Weeds
ter Phytotoxx * -
ity at
Rice plants 4-5
4th
3 5
4-5
4th OOO 2
O "
O O
O 4th
3
2. 4-5
3
3 4th
3
1 1
0
0

O CD CO

(Comparison No.2)

400
200
100

800
500
200

400
200
100

5
4th
4th

3-4
3
0

4th
3
.1

4-5

(Comparison No.6)

ci-f Vo-f Vbo 600 -4 400 2. Cl 200 0 (Comparison No.?) Untreated Control area Nit 101

3
0
0

4th
0

5 4 0

-31-QP OQ O

3a.

Annotation; Broad-leaved weeds: Monochoria, Rotala indica and Lindernia pyxidaria

The test results show that the

Herbicidal agents according to the invention are not just surprising herbicidal effectiveness against the common Heisfeld weeds, as shown by chicken millet, swamp rush and broad-leaved weeds, but also excellent compatibility with rice plants exhibit.

The herbicides according to the invention are also used Means by a much longer period of use than that from the prior art known herbicidal agents characterized.

As the soil treatment carried out in Example A shows, the herbicidal compositions are remarkable Selectivity in relation to the root of rice plants, whereby a restriction of the advantages of the herbicidal effectiveness due to the damage to the cultivated plants by the chemical treated soil, which was previously unavoidable, can be prevented.

The herbicidal compositions according to the invention can applied not only before driving, but also together with fertilizers, so that considerable labor savings can be achieved.

From Examples B and C it can be seen that the herbicidal compositions according to the invention immediately before or after planting the rice seedlings can be applied without the risk of phytotoxicity becoming noticeable power. One can therefore use a sprayer with a seedling transplanter use, whereby a separate work step for spraying can be saved.

Since the agents according to the invention are also effective used in the pre-emergence treatment of the earth's surface can be achieved, maximum effect can be achieved even with a low application rate.

Nit 101 -32-

30981 7/1135

Since the herbicidal agents according to the invention also after driving out aquatic weeds (see Example D) show sufficient effect is a considerable one Time span given in which the funds can be used successfully.

Nit 101 -33-

309817/1 18S

Claims (2)

Patent claims: 1. Herbicidal agent, characterized by a content of ^ -chlorobenzyl-NjN-hexamethylene thiol carbamate formula 0 _/ ν Cl- / \ cH ₂ -SCN HI, (I). 2. A method of combating weeds »characterized in that one ^ -chlorobenzyl-N.N-hexamethylene thiol carbamate according to claim 1 can act on weeds or their habitat. 3 · Use of ^ chlorobenzyl-NjN-hexamethylene thiol carbamate according to claim 1 for combating weeds. k. Process for the preparation of a herbicidal agent, characterized in that ^ -chlorobenzyl-NN-hexamethylene thiol carbamate according to Claim 1 is mixed with extenders and / or surface-active agents. ( 5 j ^ -chlorobenzyl-NjN-hexamethylene thiol carbamate of the formula \ __ ^ 0 y . V VcH ₂ -SCN HJ, (i). Nit 101 -34- 309817/1 185