Heterocyclic dihaloacetamides, and herbicides which contain acetanilides as herbicidal active ingredients and the dihaloacetamides as antagonistic agents

Heterocyclic dihaloacetamides of the formula ##STR1## where R.sup.1 to R.sup.6, Z and n have the meanings given in the description, are antagonistic agents which increase the toleration of herbicidal acetanilides by crops.

The present invention relates to heterocyclic dihaloacetamides, and 
herbicides which contain acetanilides as herbicidal active ingredients and 
the dihaloacetamides as antagonistic agents. 
Acetanilides of the formula 
##STR2## 
where Y.sup.1 is hydrogen or straight-chain or branched alkyl or alkoxy of 
not more than 5 carbon atoms and Y.sup.2 and Y.sup.3 are hydrogen, halogen 
or straight-chain or branched alkyl or alkoxy of not more than 5 carbon 
atoms, or Y.sup.1 and Y.sup.2 together are alkylene of not more than 6 
carbon atoms which is linked in the ortho-position and is unsubstituted or 
substituted by straight-chain or branched alkyl of not more than 4 carbon 
atoms, X is chlorine or bromine, A is alkoxy or alkoxyalkyl of not more 
than 4 carbon atoms, or is azolyl, which may be monosubstituted or 
polysubstituted by halogen or phenyl, or by alkyl, alkoxy, alkylthio or 
perfluoroalkyl, each of not more than 4 carbon atoms, or by cyano, 
carboxyl or alkoxycarbonyl where alkoxy is of not more than 4 carbon 
atoms, and A can also be a salt of an azolyl radical, which contains 2 or 
3 nitrogen atoms, and B is hydrogen or methyl, are excellent herbicides, 
but cause damage to crops such as Indian corn or other crops of the 
Gramineae family. 
It is an object of the present invention to provide antagonists which 
counterbalance this intolerance of herbicidal acetanilides by certain 
crops. 
German Laid-Open Applications DOS No. 2,218,097 and DOS No. 2,245,471 
disclose herbicides which, in addition to herbicidal active ingredients, 
contain dichloroacetamides as antagonistic compounds. The 
dichloroacetamides disclosed in German Laid-Open Application DOS No. 
2,218,097 are chiefly used for reducing undesirable crop damage caused by 
thiolcarbamates, while German Laid-Open Application DOS No. 2,245,471 also 
discloses herbicides which contain dichloroacetamides and 
chloroacetanilides, e.g. 2-chloro-2',6'-diethyl-N-butoxymethylacetanilide 
or 2-chloro-2',6'-diethyl-N-methoxymethylacetanilide. 
We have found that the above object is achieved by heterocyclic 
dihaloacetamides of the formula 
##STR3## 
where R.sup.1 is hydrogen or alkyl of 1 to 4 carbon atoms, R.sup.2 is 
hydrogen or methyl, R.sup.3 is hydrogen or alkyl of 1 to 3 carbon atoms, 
R.sup.4 is hydrogen, alkyl of 1 to 4 carbon atoms or cyclohexyl, R.sup.5 
is hydrogen or methyl, R.sup.6 is hydrogen or methyl, Z is chlorine or 
bromine and n is 0 or 1, or where R.sup.2 together with R.sup.3 is 
pentamethylene, or where R.sup.4 together with R.sup.5 is tetramethylene 
or pentamethylene, if n is 0, or where R.sup.5 together with R.sup.6 is 
tetramethylene, if n is 1, which are particularly suitable for increasing 
the toleration of herbicidal acetanilides of the formula II by plants. 
Herbicides containing an acetanilide of the formula II and a heterocyclic 
dihaloacetamide of the formula I can be used both on Indian corn and on 
other cereal crops. The good herbicidal effect of the acetanilides is 
retained, while damage to the crops is entirely or substantially avoided. 
Suitable antagonists include heterocyclic dihaloacetamides of the formula I 
where n is 0 or 1, i.e. both 1-dihaloacetyl-imidazolidin-4-ones and 
1-dihaloacetylpiperazin-3-ones. In formula I, R.sup.1 is hydrogen or alkyl 
of 1 to 4 carbon atoms, e.g. methyl, ethyl, isopropyl or isobutyl, R.sup.2 
is hydrogen or methyl, R.sup.3 is hydrogen or alkyl of 1 to 3 carbon 
atoms, e.g. methyl, ethyl or isopropyl, R.sup.4 is hydrogen, alkyl of 1 to 
4 carbon atoms, e.g. methyl, ethyl, isopropyl or tert.-butyl, or 
cyclohexyl, and R.sup.5 and R.sup.6 are each hydrogen or methyl. R.sup.2 
together with R.sup.3 can also be pentamethylene, and in addition, R.sup.4 
together with R.sup.5 can be tetramethylene or pentamethylene, if n is 0, 
or R.sup.5 together with R.sup.6 can be tetramethylene, if n is 1. 
Examples of antagonistic dihaloacetamides of the formula I are 
1-dichloroacetyl-2-spiro-cyclohexyl-4-oxo-imidazolidine, 
1-dichloroacetyl-2-isopropyl-4-oxo-imidazolidine, 
1-dichloroacetyl-2,5-dimethyl-2-isopropyl-4-oxo- imidazolidine, 
1-dichloroacetyl-2-isopropyl-4-oxo-5-methyl-imidazolidine, 
1-dichloroacetyl-2-spiro-cyclopentyl-4-oxo-imidazolidine, 
1-dichloroacetyl-2,3-diisopropyl-4-oxo-imidazolidine, 
1-dichloroacetyl-2-isopropyl-4-oxo-5,5-dimethyl-imidazolidine, 
1-dichloroacetyl-2-tert.-butyl-4-oxo-imidazolidine, 
1-dichloroacetyl-2-cyclohexyl-4-oxo-imidazolidine, 
1-dichloroacetyl-2-isopropyl-3-methyl-4-oxo-imidazolidine, 
1-dichloroacetyl-2-tert.-butyl-3-methyl-4-oxo-imidazolidine, 
1-dichloroacetyl-2-cyclohexyl-4-oxo-imidazolidine, 
1-dichloroacetyl-2-cyclohexyl-3-methyl-4-oxo-imidazolidine, 
1-dibromoacetyl-2-tert.-butyl-3-methyl-4-oxo-imidazolidine, 
1-dibromoacetyl-2-cyclohexyl-4-oxo-imidazolidine, 
1-dichloroacetyl-3-oxo-piperazine, 
1-dichloroacetyl-2-methyl-3-oxo-piperazine, 
1-dichloroacetyl-2,5-dimethyl-3-oxo-piperazine, 
1-dichloroacetyl-2,2-dimethyl-3-oxo-piperazine, 
1-dichloroacetyl-2,5,6-trimethyl-3-oxo-piperazine, 
1-dichloroacetyl-2-methyl-3-oxo-5,6-tetramethylene-piperazine, 
1-dichloroacetyl-2-ethyl-3-oxo-piperazine, 
1-dichloroacetyl-2-isopropyl-3-oxo-piperzine, 
1-dichloroacetyl-2-spirocyclohexyl-2-oxo-piperazine, 
1-dichloroacetyl-2-spirocyclohexyl-3-oxo-5,6-tetramethylene-piperazine, 
1-dibromoacetyl-2,2-dimethyl-3-oxo-piperazine and 
1-dibromoacetyl-2-methyl-3-oxo-piperazine. 
Heterocyclic dichloroacetamides of the formula I can be obtained by 
reacting an amine of the formula 
##STR4## 
where R.sup.1 to R.sup.6 and n have the above meanings, with a 
dihaloacetyl chloride of the formula Z.sub.2 CH--COCl, where Z is chlorine 
or bromine, in the presence of a hydrogen halide acceptor and a solvent, 
at from 0.degree. to 30.degree. C. 
Suitable solvents are anhydrous solvents, e.g. hydrocarbons or 
halohydrocarbons, such as toluene, the xylenes, chlorobenzene, methylene 
chloride and ethylene chloride, ethers, such as diethyl ether, methyl 
tert.-butyl ether, tetrahydrofuran or 1,4-dioxane, and nitriles, such as 
acetonitrile, and two-phase systems, e.g. water and toluene, or water and 
methylene chloride. 
Suitable hydrogen halide acceptors are alkali metal carbonates and 
bicarbonates, aqueous solutions of alkali metal hydroxides, and 
trialkylamines, N,N-dialkylanilines, e.g. N,N-dimethylaniline, and 
pyridine bases. Advantageously, 1 mole of the amine of the formula III is 
reacted with 1 to 1.2 moles of dihaloacetyl chloride. 1-1.2 moles of 
hydrogen halide acceptor are added per mole of dihaloacetyl chloride. 
Imidazolidin-4-ones of the formula III are prepared by reacting a ketone or 
aldehyde with a nitrile or amide of an .alpha.-aminoacid (J. Chem. Soc. 
(1951), 3479), or by converting an .alpha.-aminoacid ester into a Schiff 
base and then reacting the base with ammonia or a primary amine (Rec. 
Trav. Chim. 111 (1971), 284). 
Piperazinones of the formula III are obtained, for example, by reacting a 
cyanohydrin with an aliphatic 1,2-diamine (U.S. Pat. No. 2,700,668). 
Preparation of the amines of the formula III 
1. 137 g of cyclohexanone were added to a suspension of 77 g (0.69 mole) of 
glycinamide hydrochloride in 300 ml of toluene, and a mixture of 120 ml of 
methanol and 125.5 g of 30% strength NaOCH.sub.3 solution (0.7 mole) was 
then added dropwise at 25.degree. C. The mixture was refluxed for 4 hours 
and cooled to 5.degree. C., the precipitated NaCl was filtered off with 
suction and the filtrate was evaporated. Trituration of the residue with 
naphtha gave 44 g (41% of theory) of 
2-spiro-cyclohexyl-4-oxo-imidazolidine or melting point 
118.degree.-119.degree. C. 
2. 279 g (2 moles) of methyl alanate hydrochloride were dissolved in 100 ml 
of water, and 216 g (3 moles) of isobutyraldehyde were rapidly added. 242 
g (2.4 moles) of triethylamine were then added dropwise at from 10 to 
15.degree. C., and the mixture was stirred for 16 hours and extracted with 
250 ml of methyl tert.-butyl ether. The organic phase was dried, and 
concentrated under reduced pressure to give 281 g (89% of theory) of an 
oil of the formula 
EQU (CH.sub.3).sub.2 CH--CH.dbd.N--CH(CH.sub.3)--COOCH.sub.3 
62.8 g (0.4 mole) of this Schiff base were dissolved in 200 ml of methanol, 
and gaseous methylamine was added at 25.degree. C. until the mixture was 
saturated. The mixture was stirred for 16 hours and concentrated under 
reduced pressure to give 58 g (93% of theory) of 
3,5-dimethyl-2-isopropyl-4-oxo-imidazolidine as an oil. 
3. N-(2-Methyl-propylidene)-glycine ethyl ester of boiling point 
53.degree.-56.degree. C./0.1 mbar was obtained in 90% yield from glycine 
methyl ester hydrochloride and isobutyraldehyde in a reaction similar to 
that described under 2. The reaction of this Schiff base with gaseous 
ammonia in methanol gave an 80% yield of 2-isopropyl-4-oxo-imidazolidine 
as an oil. 
4. 138.5 g (1.95 moles) of acetaldehyde cyanohydrin were added dropwise to 
a solution of 176 g (2 moles) of 2,3-diaminobutane in 250 ml of water, 
with cooling at 25.degree. C. The mixture was then heated at the boil for 
8 hours, until no more ammonia was split off. The reaction mixture was 
then distilled under reduced pressure to give 200 g (72% of theory) of 
2,5,6-trimethyl-3-oxo-piperazine of boiling point 123.degree. C./0.5 mbar. 
5. 2-Methyl-3-oxo-5,6-tetramethylene-piperazine of melting point 
177.degree.-178.degree. C. was obtained from 1,2-diaminocyclohexane and 
acetaldehyde cyanohydrin by a reaction similar to that described under 4. 
6. 2,2-Dimethyl-3-oxo-piperazine of melting point 133.degree.-135.degree. 
C. was obtained from ethylenediamine and acetone cyanohydrin by a reaction 
similar to that described under 4. 
Preparation of the heterocyclic dihaloacetamides of the formula I 
I. 45 g (0.35 mole) of 2-isopropyl-4-oxo-imidazolidine (Example 3) were 
dissolved in 250 ml of methyl tert.- butyl ether, 17.2 g (0.43 mole) of 
sodium hydroxide in 20 ml of water were added, and 57 g (0.39 mole) of 
dichloroacetyl chloride were then added dropwise at from 10.degree. to 
15.degree. C. The mixture was stirred for 10 hours and the solid 
precipitate was filtered off with suction, washed with water and dried 
under reduced pressure to give 41 g (49% theory) of 
1-dichloroacetyl-2-isopropyl-4-oxoimidazolidine of melting point 
172.degree.-173.degree. C. 
II. A solution of 8 g (0.2 mole) of sodium hydroxide in 15 ml of water was 
added to a solution of 20 g (0.18 mole) of 2-methyl-piperazin-3-one in 150 
ml of methylene chloride. 26.6 g (0.18 mole) of dichloroacetyl chloride 
were then added dropwise at from 10.degree. to 15.degree. C. The mixture 
was stirred at 25.degree. C. for 10 hours and the precipitated crude 
product was filtered off with suction, washed with water and 
recrystallized from a 2:1 mixture of isopropanol and H.sub.2 O to give 
14.4 g (36% theory) of 1-dichloroacetyl-2-methyl-3-oxo-piperazine of 
melting point 167.degree.-168.degree. C. 
The dihaloacetamides listed in Tables 1 and 2 may be obtained in a similar 
manner. 
TABLE 1 
______________________________________ 
##STR5## 
Melting 
point 
No. R.sup.1 R.sup.2 
R.sup.3 
R.sup.4 R.sup.5 
Z [.degree.C.] 
______________________________________ 
1 H H H i-C.sub.3 H.sub.7 
H Cl 172-173 
2 H H CH.sub.3 
i-C.sub.3 H.sub.7 
H Cl 198-199 
3 CH.sub.3 
H CH.sub.3 
i-C.sub.3 H.sub.7 
H Cl 114-115 
4 H H H (CH.sub.2).sub.5 
Cl 218 
5 i-C.sub.3 H.sub.7 
H H i-C.sub.3 H.sub.7 
H Cl 
6 H CH.sub.3 
CH.sub.3 
i-C.sub.3 H.sub.7 
H Cl 
7 H H H tert.-C.sub.4 H.sub.9 
H Cl 174-176 
8 H H H C.sub.6 H.sub.11 
H Cl 
9 CH.sub.3 
H H i-C.sub.3 H.sub.7 
H Cl 
10 CH.sub.3 
H H tert.-C.sub.4 H.sub.9 
H Cl 112 
11 H H H C.sub.6 H.sub.11 
H Cl 209 
12 CH.sub.3 
H H C.sub.6 H.sub.11 
H Cl 152 
13 H H H C.sub.6 H.sub.11 
H Br 202 
14 CH.sub.3 
H H C.sub.6 H.sub.11 
H Br 
15 n-C.sub.4 H.sub.9 
H H tert.-C.sub.4 H.sub.9 
H Cl 
16 i-C.sub.3 H.sub.7 
H H tert.-C.sub.4 H.sub.9 
H Cl 
17 H CH.sub.3 
CH.sub.3 
i-C.sub.3 H.sub.7 
H Cl 
18 CH.sub.3 
CH.sub.3 
CH.sub.3 
i-C.sub.3 H.sub.7 
H Cl 
19 CH.sub.3 
H H tert.-C.sub.4 H.sub.9 
H Br 141 
______________________________________ 
TABLE 2 
______________________________________ 
##STR6## 
Melting 
point 
No. R.sup.2 
R.sup.3 R.sup.4 
R.sup.5 
R.sup.6 
Z [.degree.C.] 
______________________________________ 
20 H H H H H Cl 
21 H CH.sub.3 
H H H Cl 167-168 
22 CH.sub.3 
H H H CH.sub.3 
Cl 153-155 
23 CH.sub.3 
CH.sub.3 
H H H Cl 196-197 
24 H CH.sub.3 
CH.sub.3 
H CH.sub.3 
Cl 145-147 
25 CH.sub.3 
H H (CH.sub.2).sub.4 
Cl 247-248 
26 H C.sub.2 H.sub.5 
H H H Cl 
27 H i-C.sub.3 H.sub.7 
H H H Cl 
28 (CH.sub.2).sub.5 
H H H Cl 
29 (CH.sub.2 H.sub.5 
H (CH.sub.2).sub.4 
Cl 
30 H CH.sub.3 
H H H Br 
31 H CH.sub.3 
CH.sub.3 
H H Br 
32 CH.sub.3 
CH.sub.3 
H H H Br 135 (decom- 
position) 
______________________________________ 
The dihaloacetamides of the formula I can be used to improve the toleration 
by crops of those acetanilides of the formula II where Y.sup.1 is 
hydrogen, alkyl of not more than 5 carbon atoms, e.g. methyl, ethyl, 
n-propyl, i-propyl, n-butyl, sec.-butyl, i-butyl, tert.-butyl or normal or 
branched pentyl, or alkoxy of not more than 5 carbon atoms, e.g. methoxy, 
ethoxy, propoxy, butoxy or pentyloxy, and Y.sup.2 and Y.sup.3 are 
hydrogen, halogen, e.g. fluorine, chlorine, bromine or iodine, alkyl of 
not more than 5 carbon atoms, e.g. methyl, ethyl, n-propyl, i-propyl, 
n-butyl, sec.-butyl, i-butyl, tert.-butyl or normal or branched pentyl, or 
alkoxy of not more than 5 carbon atoms, e.g. methoxy, ethoxy, propoxy, 
butoxy or pentyloxy, or Y.sup.1 together with Y.sup.2 is alkylene of not 
more than 6 carbon atoms, which is linked in the ortho-position and is 
unsubstituted or substituted by alkyl of not more than 4 carbon atoms, 
such as ethylene, trimethylene, tetramethylene, 1-methyl-trimethylene, 
1,1-dimethyltrimethylene or 1,1-dimethyl-tetramethylene, X is chlorine or 
bromine, preferably chlorine, A is azolyl, e.g. pyrrolyl, pyrazolyl, 
imidazolyl, 1,2,4-triazolyl, 1,2,3-triazolyl or tetrazolyl, which can be 
monosubstituted or polysubstituted by halogen or phenyl, or by alkyl, 
alkoxy, alkylthio or perfluoroalkyl, each of not more than 4 carbon atoms, 
or by cyano, carboxyl or alkoxycarbonyl, where alkoxy is of not more than 
4 carbon atoms, or A is alkoxy or alkoxyalkyl of not more than 4 carbon 
atoms, e.g. methoxy, ethoxy, n-butoxy, methoxymethyl, 2-methoxymethyl or 
ethoxymethyl, and B is hydrogen or methyl. 
Moreover, if the azolyl radical A contains 2 or 3 nitrogen atoms, it can 
also be bonded in the form of a salt to one of the conventional strong 
inorganic or organic acids, such as hydrochloric acid, nitric acid, 
sulfuric acid, trichloroacetic acid, methanesulfonic acid, 
perfluorohexanesulfonic acid or dodecylbenzenesulfonic acid. 
Preferred acetanilides of the formula II are those which carry methyl or 
ethyl in the 2- and 6-positions of the phenyl ring and hydrogen or methyl 
in the 3-position. X is preferably chlorine, while A is, in particular, 
azolyl, e.g. pyrazolyl, 3,5-dimethylpyrazolyl, 2-methylpyrazol-5-yl, 
1,2,4-triazolyl or 4,5-dichloroimidazolyl, or ethoxy, n-butoxy or 
methoxymethyl, and B is hydrogen or methyl. 
In particular, the herbicides according to the invention contain the 
following acetanilides: 
2-chloro-2',6-dimethyl-N-(pyrazol-1-yl-methyl)-acetanilide, 
2-chloro-2'-methyl-6'-ethyl-N-(pyrazol-1-yl-methyl)-acetanilde, 
2-chloro-2',6'-dmethyl-N-(3,5-dimethylpyrazol-1-yl-methyl)-acetanilide, 
2-chloro-2',6'-dimethyl-N-(1,2,4-triazol-1-yl-methyl)-acetanilide, 
2-chloro-2',3',6'-trimethyl-N-(pyrazol-1-yl-methyl)-acetanilide, 
2-chloro-2'-methyl-6'-ethyl-N-(3,5-dimethyl-pyrazol-1-yl-methyl)-acetanili 
de, 2-chloro-2',6'-diethyl-N-(3,5-dimethylpyrazol-1-yl-methyl)-acetanilide, 
2-chloro-2',3',6'-trimethyl-N-(3,5-dimethyl-pyrazol-1-yl-methyl)-acetanili 
de, 2-chloro-2',6'-diethyl-N-(pyrazol-1-yl-methyl)-acetanilide, 
2-chloro-2',6'-dimethyl-N-(4,5-dichloroimidazol-1yl-methyl)-acetanilide, 
2-chloro-2'-methyl-6'-ethyl-N-(4,5-dichloroimidazol-1-yl-methyl)-acetanili 
de, 
2-chloro-2',6'-diethyl-N-(4,5-dichloroimidazol-1-yl-methyl)-acetanilide, 2 
-chloro-2'-methyl-6'-ethyl-N-(1,2,4-triazol-1-yl-methyl)-acetanilide, 
2-chloro-2',6'-diethyl-N-(1,2,4-triazol-1-yl-methyl)-acetanilide, 
2-chloro-2',3',6'-trimethyl-N-(1,2,4-triazol-1-yl-methyl)-acetanilide, 
2-chloro-2',6'-dimethyl-N-(2-methoxyethyl)-acetanilide, 
2-chloro-2'-methyl-6'-ethyl-N-ethoxymethyl-acetanilide, 2 
-chloro-2',6'-diethyl-N-(n-butoxymethyl)-acetanilide, 
2-chloro-2'-ethyl-6'-methyl-N-(1-methyl-2-methoxy-ethyl)-acetanilide and 
2- chloro-2',6'-dimethyl-N-[(2-methyl-pyrazol-5-yl)-methyl]acetanilide. 
German Laid-Open Applications DOS No. 2,648,008, DOS No. 2,744,396, DOS No. 
2,305,495, DOS No. 2,328,340 and DOS No. 2,842,315 and U.S. Pat. No. 
3,547,620 disclose the acetanilides of the formula II and their 
preparation. 
Herbicidal active ingredients and antagonistic compounds can be worked into 
the soil together or separately, before or after sowing. The acetanilides 
are in most cases applied to the surface of the soil immediately after the 
seeds have been sown or in the period between sowing and emergence of the 
young plants. Treatment during emergence is also possible. In all cases, 
the antagonist can be applied at the same time as the herbicidal active 
ingredient. Separate application, first of the antagonist and then of the 
herbicidal active ingredient or vice versa, to the field is also possible 
as long as the interval between the two applications is not so long that 
the herbicidal active ingredient has already caused damage to the crop. 
The active ingredient and antagonist can be formulated separately or 
together as sprays, in suspendable, emulsifiable or soluble form, or as 
granules. Treatment of the crop seeds with the antagonist before sowing is 
also conceivable, in which case the herbicidal active ingredient is 
applied by itself in a conventional manner. 
Different amounts of a given antagonistic compound may be required for the 
same herbicidal acetanilide, depending on the crop, and the proportions in 
which the acetanilide and dihaloacetamide are used can vary within wide 
limits, depending on the structure of the acetanilide and of the 
dihaloacetamide and on the particular crop. A suitable weight ratio of 
herbicidal active ingredient to antagonistic compound is from 1:2 to 
1:0.01, preferably from 1:0.25 to 1:0.05. 
The new herbicidal agents may contain, in addition to acetanilide and 
dihaloacetamide, further herbicidal or growth-regulating active 
ingredients having a different chemical structure, the antagonistic effect 
being retained. They may for instance contain 
2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine, 
2-(2-chloro-4-ethylamino-1,3,5-triazin-6-yl-amino)-2-methyl-propionitrile, 
N-(1-ethyl-n-propyl)-2,6-dinitro-3,4-dimethylaniline or 
1-(4-isopropyl-phenyl)-3,3-dimethylurea as additional herbicidal active 
ingredients. 
The agents according to the invention, or-- where applied separately-- the 
herbicidal active ingredients and antidote, are applied for instance in 
the form of directly sprayable solutions, powders, suspensions (including 
high-percentage aqueous, oily or other suspensions), dispersions, 
emulsions, oil dispersions, pastes, dusts, broadcasting agents, or 
granules by spraying, atomizing, dusting, broadcasting or watering. The 
forms of application depend entirely on the purpose for which the agents 
are being used. 
For the preparation of solutions, emulsions, pastes and oil dispersions to 
be sprayed direct, mineral oil fractions of medium to high boiling point, 
such as kerosene or diesel oil, further coal-tar oils, and oils of 
vegetable or animal origin, aliphatic, cyclic and aromatic hydrocarbons 
such as benzene, toluene, xylene, paraffin, tetrahydronaphthalene, 
alkylated naphthalenes and their derivatives such as methanol, ethanol, 
propanol, butanol, chloroform, carbon tetrachloride, cyclohexanol, 
cyclohexanone, chlorobenzene, isophorone, etc., and strongly polar 
solvents such as dimethylformamide, dimethyl sulfoxide, 
N-methylpyrrolidone, water, etc. are suitable. 
Aqueous formulations may be prepared from emulsion concentrates, pastes, 
oil dispersions or wettable powders by adding water. To prepare emulsions, 
pastes and oil dispersions the herbicidal active ingredients and/or 
antidote as such or dissolved in an oil or solvent may be homogenized in 
water by means of wetting or dispersing agents, adherents or emulsifiers. 
Concentrates which are suitable for dilution with water may be prepared 
from herbicidal active ingredient and/or antidote, wetting agent, 
adherent, emulsifying or dispersing agent and possibly solvent or oil. 
Examples of surfactants are: alkali metal, alkaline earth metal and 
ammonium salts of ligninsulfonic acid, naphthalenesulfonic acids, 
phenolsulfonic acids, alkylaryl sulfonates, alkyl sulfates, and alkyl 
sulfonates, alkali metal and alkaline earth metal salts of 
dibutylnaphthalenesulfonic acid, lauryl ether sulfate, fatty alcohol 
sulfates, alkali metal and alkaline earth metal salts of fatty acids, 
salts of sulfated hexadecanols, heptadecanols, and octadecanols, salts of 
sulfated fatty alcohol glycol ethers, condensation products of sulfonated 
naphthalene and naphthalene derivatives with formaldehyde, condensation 
products of naphthalene or naphthalenesulfonic acids with phenol and 
formaldehyde, polyoxyethylene octylphenol ethers, ethoxylated 
isooctylphenol, ethoxylated octylphenol and ethoxylated nonylphenol, 
alkylphenol polyglycol ethers, tributylphenol polyglycol ethers, alkylaryl 
polyether alcohols, isotridecyl alcohol, fatty alcohol ethylene oxide 
condensates, ethoxylated castor oil, polyoxyethylene alkyl ethers, 
ethoxylated polyoxypropylene, lauryl alcohol polyglycol ether acetal, 
sorbitol esters, lignin, sulfite waste liquors and methyl cellulose. 
Powders, dusts and broadcasting agents may be prepared by mixing or 
grinding the herbicidal active ingredients and/or antidote with a solid 
carrier. 
Granules, e.g., coated, impregnated or homogeneous granules, may be 
prepared by bonding the active ingredients to solid carriers. Examples of 
solid carriers are mineral earths such as silicic acid, silica gels, 
silicates, talc, kaolin, Attaclay, limestone, lime, chalk, bole, loess, 
clay, dolomite, diatomaceous earth, calcium sulfate, magnesium sulfate, 
magnesium oxide, ground plastics, fertilizers such as ammonium sulfate, 
ammonium phosphate, ammonium nitrate, and ureas, and vegetable products 
such as grain flours, bark meal, wood meal, and nutshell meal, cellulosic 
powders, etc. 
The formulations contains from 0.1 to 95, and preferably 0.5 to 90%, by 
weight of herbicidal active ingredient and antidote. Application rates are 
from 0.2 to 5 kg of active ingredient per hectare. This amount of active 
ingredient is applied, conjointly or in a separate operation, with such an 
amount of antidote that the weight ratio of herbicidal active ingredient 
to antagonistic compound is from 1:2 to 1:0.01, and preferably from 1:0.25 
to 1:0.05.

Examples of formulations are given below. 
I. 40 parts by weight of a mixture of 4 parts by weight of 
2-chloro-2',6'-dimethyl-N-(pyrazol-1-yl-methyl)-acetanilide and 1 part by 
weight of 1-dichloroacetyl-2-isopropyl-4-oxo-imidazolidine is intimately 
mixed with 10 parts of the sodium salt of a phenolsulfonic 
acid-urea-formaldehyde condensate, 2 parts of silica gel and 48 parts of 
water to give a stable aqueous dispersion. Dilution in 100,000 parts by 
weight of water gives an aqueous dispersion containing 0.04 wt % of active 
ingredient mixture. 
II. 3 parts by weight of a mixture of 1 part by weight of 
2-chloro-2'-methyl-6'-ethyl-N-(pyrazol-1-yl-methyl)-acetanilide and 1 part 
by weight of 1-dichloroacetyl-2,2-dimethyl-3-oxo-piperazine is intimately 
mixed with 97 parts by weight of particulate kaolin. A dust is obtained 
containing 3% by weight of the mixture of active ingredients. 
III. 30 parts by weight of a mixture of 1 part by weight of 
2-chloro-2'methyl-6'-ethyl-N-(1,2,4-triazol-1-yl-methyl)-acetanilide and 2 
parts by weight of 1-dichloroacetyl-2,5,6-trimethyl-3-oxo-piperazine is 
intimately mixed with a mixture consisting of 92 parts by weight of 
powdered silica gel and 8 parts by weight of paraffin oil which has been 
sprayed onto the surface of this silica gel. A formulation of the active 
ingredient mixture is obtained having good adhercene. 
IV. 20 parts by weight of a mixture of 8 parts by weight of 
2-chloro-2'-methyl-6'-ethyl-N-ethoxymethyl-acetanilide and 1 part by 
weight of 1-dichloroacetyl-2-isopropyl-3,5-dimethyl-4-oxo-imidazoline is 
intimately mixed with 2 parts of the calcium salt of 
dodecylbenzenesulfonic acid, 8 parts of a fatty alcohol polyglycol ether, 
2 parts of the sodium salt of a phenolsulfonic acid-urea-formaldehyde 
condensate and 68 parts of a paraffinic mineral oil. A stable oily 
dispersion is obtained. 
V. 20 parts by weight of a mixture of 10 parts by weight of 
2-chloro-2',6'-dimethyl-N-(2-methoxyethyl)-acetanilide and 1 part by 
weight of 1-dichloracetyl-2-methyl-3-oxo-5,6-tetramethylene-piperazine is 
dissolved in a mixture consisting of 40 parts by weight of cyclohexanone, 
30 parts by weight of isobutanol, 20 parts by weight of the adduct of 7 
moles of ethylene oxide and 1 mole of isooctylphenol, and 10 parts by 
weight of the adduct of 40 moles of ethylene oxide and 1 mole of castor 
oil. By pouring the solution into 100,000 parts by weight of water and 
finely distributing it therein, an aqueus disperson is obtained containing 
0.02% by weight of the active ingredient mixture. 
The influence of various representatives of herbicides according to the 
invention on the growth of unwanted and crop plants compared with that of 
herbicides consisting of the same herbicidal active ingredients and a 
prior art antagonistic compound of chemically similar structure is 
demonstrated in the following biological experiments. These experiments 
show that the tolerance of the herbicidal acetanilides by combined 
application with the dihaloacetamides is decisively improved and the 
herbicidal effectiveness retained. 
The series of experiments were carried out in the greenhouse. 
Plastic boxes 51 cm long, 32 cm wide and 6 cm deep were filled with loamy 
sand (ph:6 to 7) containing about 1.5 to 3% humus. Indian corn (Zea mays) 
and barley (Hordeum vulgare) were sown shallow, in rows, in this 
substrate. Echinochloa crus-galli and Alopecurus myosuroides were 
scattered at random as unwanted plants. The non-sterilized soil also 
additionally contained viable weed seeds which contributed to the weed 
population. A field with crop plants growing in it and infested with weeds 
was thus simulated. 
The active ingredients and antagonists were applied separately and in the 
mixtures given below. They were emulsified or suspended in water as 
vehicle and the liquor was sprayed through finely distributing nozzles 
onto the soil surface, either immediately after sowing or prior to 
emergence of the test plants. In some instances, the agents were also 
incorporated into the soil before the crop plants were sown. For the seed 
treatment the seed was powdered with a solid formulation of the active 
ingredients, or soaked for a certain period of time in a liquid 
formulation (suspension, emulsion, solution) of the antagonistic compound, 
dried to such a degree that the seeds no longer stuck to each other, and 
then sown. Seed coating is also possible. After sowing and treatment, the 
boxes were sprinkler-irrigated and covered with transparent plastic hoods 
until the plants emerged. These measures ensured that the plants 
germinated and took root uniformly. The boxes were set up in the 
greenhouse at from 15.degree. to 25.degree. C. 
These greenhouse experiments were monitored until 3 to 5 Indian corn leaves 
had developed. No more damage due to the herbicidal agents was to be 
expected after this stage. In the case of barley, the test period was from 
2 to 3 weeks. 
The scale for assessing the action of the agents was 0 to 100, 0 denoting 
normal emergence and development of the plants, with reference to the 
untreated control, and 100 denoting non-germination or withering of the 
plants. 
As comparative agents, herbicidal agents were used which contained, in 
addition to he herbicidal acetanilide, N-dichloroacetyl-morpholine (V) 
(disclosed in German Laid-Open Application DE-OS No. 2,218,097) as 
antagonistic agent. 
TABLE 3 
______________________________________ 
Improvement in the tolerance of 2-chloro-2',6'-dimethyl- 
N--(pyrazol-1-yl-methyl)-acetanilide (A) 
by Indian corn, by admixing antagonistic compounds; 
preemergence treatment in the greenhouse 
Test plants 
Herbicidal and % damage 
active Antagonistic 
Appln. rate Echinochloa 
ingredient 
compound [kg/ha] Zea mays 
crus-galli 
______________________________________ 
A -- 1.0 64 100 
A V 1.0 + 0.125 
37 100 
A 23 1.0 + 0.125 
8 100 
1.0 + 0.1 8 100 
1.0 + 0.06 12 100 
A 21 1.0 + 0.25 12 100 
1.0 + 0.1 18 100 
A 1 1.0 + 0.125 
0 -- 
______________________________________ 
0 = normal emergence, no damage 
100 = nonemergence, or plants withered 
TABLE 4 
______________________________________ 
Improvement in the tolerance of 2-chloro-2',6'-dimethyl- 
N--(pyrazol-1-yl-methyl)-acetanilide (A) 
by cereals, by admixing an antagonistic compound; 
preemergence treatment in the greenhouse 
Test plants 
Herbicidal and % damage 
active Antagonistic 
Appln. rate 
Hordeum Alopecurus 
ingredient 
compound [kg/ha] vulgare myosuroides 
______________________________________ 
A -- 0.5 65 90 
A 25 0.5 + 0.5 15 95 
______________________________________ 
0 = normal emergence, no damage 
100 = nonemergence, or plants withered 
TABLE 5 
__________________________________________________________________________ 
Improvement in the tolerance by Indian corn of 2-chloro-2',6'-dimethyl-N-- 
(pyrazol-1-yl-methyl)-acetanilide (A) by seed treatment 
Test plants 
Herbicidal and % damage 
active 
Antagonistic 
Appln. rate Echinochloa 
ingredient 
compound 
(a.i. + antagonist kg) 
Method Zea mays 
crus-galli 
__________________________________________________________________________ 
A -- 1.0 PES* 68 99 
A 23 1.0 PES 0 100 
+ 250 g as seed treatment 
per 100 kg seed 
A 23 1.0 PES 0 100 
+ 50 kg as seed treatment 
per 100 kg seed 
A 22 1.0 PES 10 100 
+ 250 g as seed treatment 
per 100 kg seed 
A 22 1.0 PES 10 100 
+ 50 g as seed treatment 
per 100 kg seed 
__________________________________________________________________________ 
*PES = Preemergence spraying (after sowing of crop and unwanted plants) 
The seed was treated with the antagonistic compound, and the herbicidal 
active ingredient was sprayed after the seed had been sown. 
TABLE 6 
______________________________________ 
Improvement in the tolerance by Indian corn of 2-chloro-2',6'-di- 
methyl-N--(2-methoxyethyl)-acetanilide (B) 
and 2-chloro-2'-methyl-6'-ethyl-N--(ethoxymethyl)-acetanilide (C); 
preemergence application in the greenhouse 
Herbicidal Damage to crop plant 
active Antagonistic 
Appln. rate 
Indian corn in % 
ingredient 
compound [kg/ha] Zea mays 
______________________________________ 
B -- 1.0 45 
B 23 1.0 + 0.25 0 
23 1.0 + 0.125 
5 
C 2.0 32 
C 23 2.0 + 0.25 5 
______________________________________