1-(2-oxyaminosulphonylphenylsulphonyl)-3-heteroaryl-ureas

Abstract

The invention relates to new 1-(2-oxyaminosulphonylphenylsulphonyl)-3-heteroaryl-ureas of the general formula (I) ##STR1## in which R¹ represents an optionally substituted radical from the series comprising alkyl, alkenyl, alkinyl, cycloalkyl, cycloalkylalkyl, aralkyl and aryl,

R² represents hydrogen or an optionally substituted radical from the series comprising alkyl, alkenyl, alkinyl and aralkyl and

R³ represents an optionally substituted and/or optionally fused six-membered aromatic heterocyclic radical containing at least one nitrogen atom, the following compounds being excluded: 1-(2-methoxyaminosulphonylphenylsulphonyl)-, 1-(2-ethoxyaminosulphonylphenylsulphonyl-, 1-(2-propoxyaminosulphonylphenylsulphonyl)-, 1-(2-isopropoxyaminosulphonylphenylsulphonyl)- and 1-(2-butoxyaminosulphonylphenylsulphonyl)-3-(4,6-dimethylpyrimidin-2-yl)-u rea -3-(4,6-diethyl-pyrimidin-2-yl)-urea, -3-(4,6-dipropylpyrimidin-2-yl)-urea, -3-(4,6-diisopropyl-pyrimidin-2-yl)-urea and -3-(4,6-dibutyl-pyrimidin-2-yl)-urea, processes for their preparation and their use as herbicides.

Description

The invention relates to new 1-(2-oxyaminosulphonylphenylsulphonyl)-3-heteroaryl-ureas, processes for their preparation and their use as herbicides.

It is known that certain 1-arylsulphonyl-3-heteroarylureas, such as, for example, 1-(2-methoxyphenylsulphonyl)-3-(4,6-dimethyl-pyrimidin-2-yl)-urea, have a herbicidal action. However, the action of these compounds is not always completely satisfactory (compare U.S. Pat. No. 4,169,719).

New 1-(2-oxyaminosulphonylphenylsulfphonyl)-3-heteroaryl-ureas of the general formula (I) ##STR2## in which R¹ represents an optionally substituted radical from the series comprising alkyl, alkenyl, alkinyl, cycloalkyl, cycloalkylalkyl, aralkyl and aryl,

R² represents hydrogen or an optionally substituted radical from the series comprising alkyl, alkenyl, alkinyl and aralkyl and

R³ represents an optionally substituted and/or optionally fused six-membered aromatic heterocyclic radical containing at least one nitrogen atom,

have now been found, the following compounds being excluded: 1-(2-methoxyaminosulphonylphenylsulphonyl)-, 1-(2-ethoxyaminosulphonylphenylsulphonyl)-, 1-(2-propoxyaminosulphonylphenylsulphonyl)-, 1-(2-isopropoxyaminosulphonylphenylsulphonyl)- and 1-(2-butoxyaminosulphonylphenylsulphonyl)-, -3-(4,6-dimethyl-pyrimidin-2-yl)-urea, -3-(4,6-diethyl-pyrimidin-2-yl)-urea, -3-(4,6-dipropylpyrimidin-2-yl)-urea, -3-(4,6-diisopropyl-pyrimidin-2-yl)- urea and -3-(4,6-dibutyl-pyrimidin-2-yl)-urea.

The new compounds of the formula (I) are obtained by a process in which

(a) benzodisultams of the formula (II) ##STR3## in which R¹, R² and R³ have the abovementioned meanings, are reacted with water, if appropriate in the presence of bases and if appropriate in the presence of diluents, or

(b) benzene-1,2-disulphonic acid dichloride of the formula (III) ##STR4## is reacted with oxyguanidine derivatives of the formula (IV) ##STR5## in which R¹, R² and R³ have the abovementioned meaning, in the presence of acid acceptors and if appropriate in the presence of diluents, and the compounds of the formula (II) thereby obtained are reacted--without intermediate isolation--with water, if appropriate in the presence of bases and if appropriate in the presence of diluents.

The new 1-(2-oxyaminosulphonylphenylsulphonyl)-3-heteroaryl-ureas of the formula (I) are distinguished by a powerful herbicidal activity.

Surprisingly, the new compounds of the formula (I) exhibit a considerably better herbicidal action than the already known urea derivatives of the same type of action.

The invention preferably relates to compounds of the formula (I) in which

R¹ represents C₁ -C₁2 -alkyl inention invention act as total or selective herbicides depends essentially on the amount used.

The active compounds according to the invention can be used, for example, in connection with the following plants:

Dicotyledon weeds of the genera: Sinpis Sinapis, Lepidium, Galium, Stellaria, Matricaria, Anhemis Anthemis, Galinsoga, Chenopodium, Urtica, Senecio, Amaranthus, Portulaca, Xanthium, Convolvulus, Ipomoea, Polygonum, Sesbania, Ambrosia, Cirsium, Carduus, Sonchus, Solanum, Rorippa, Rotala, Lindernia, Lamium, Beronica Veronica, Abutilon, Emex, Datura, Viola, Galeopsis, Papaver and Centaurea.

Dicotyledon cultures of the genera: Gossypium, Glycine, Beta, Daucus, Phaseolus, Pisum, Solanum, Linum, Ipomoea, Vicia, Nicotiana, Lycopersicon, Arachis, Brassica, Lactuca, Cucumis and Cucurbita.

Monocotyledon weeds of the genera: Echinochloa, Setaria, Panicum, Digitaria, Phleum, Poa, Festuca, Eleusine, Brachiaria, Lolium, Bromus, Avena, Cyperus, Sorghum, Agropyron, Cynodon, Monochoria, Fimbristylis, Sagittaria, Eleocharis, Scirpus, Paspalum, Ischaemum, Sphenoclea, Dactyloctenium, Agrostis, Alopecurus and Apera.

Monocotyledon cultures of the genera: Oryza, Zea, Triticum, Hordeum, Avena, Secale, Sorghum, Panicum, Saccharum, Ananas, Asparagus and Allium.

However, the use of the active compounds according to the invention is in no way restricted to these genera, but also extends in the same manner to other plants.

The compounds are suitable, depending on the concentration, for the total combating of weeds, for example on industrial terrain and rail tracks, and on paths and squares with or without tree plantings. Equally, the compounds can be employed for combating weeds in perennial cultures, for example afforestations, decorative tree plantings, orchards, vineyards, citrus groves, nut orchards, banana plantations, coffee plantations, tea plantations, rubber plantations, oil palm plantations, cocoa plantations, soft fruit plantings and hopfields, and for the selective combating of weeds in annual cultures.

The active compounds can be converted to the customary formulations, such as solutions, emulsions, wettable powders, suspensions, powders, dusting agents, pastes, soluble powders, granules, suspension-emulsion concentrates, natural and synthetic materials impregnated with active compound, and very fine capsules in polymeric substances.

These formulations are produced in known manner, for example by mixing the active compounds with extenders, that is liquid solvents and/or solid carirers carriers, optionally with the use of surface-active agents, that is emulsifying agents and/or dispersing agents and/or foam-forming agents.

In the case of the use of water as an extender, organic solvents can, for example, also be used as auxiliary solvents. As liquid solvents, there are suitable in the main: aromatics, such as xylene, toluene or alkyl naphthalenes, chlorinated aromatics and chlorinated aliphatic hydrocarbons, such as chlorobenzenes, chloroethylenes or methylene chloride, aliphatic hydrocarbons, such as cyclohexane or paraffins, for example petroleum fractions, mineral and vegetable oils, alcohols, such as butanol or glycol as well as their ethers and esters, ketones, such as acetone, methyl ethyl ketone, methyl isobutyl ketone or cyclohexanone, strongly polar solvents, such as dimethylformamide and dimethylsulphoxide, as well as water.

As solid carrier there are suitable: for example ammonium salts and ground natural minerals, such as kaolins, clays, talc, chalk, quartz, attapulgite, montmorillonite or diatomaceous earth, and ground synthetic minerals, such as highly disperse silicic acid, alumina and silicates, as solid carriers for granules there are suitable: for example crushed and fractionated natural rocks such as calcite, marble, pumice, sepiolite and dolomite, as well as synthetic granules of inorganic and organic meals, and granules of organic material such as sawdust, coconut shells, maize cobs and tobacco stalks; as emulsifying and/or foam-forming agents there are suitable: for example non-ionic and anionic emulsifiers, such as polyoxyethylene-fatty esters, polyoxyethylene-fatty alcohol ethers, for example alkylaryl polyglycol ethers, alkylsulphonates, alkylsulphates, arylsulphonates as well as albumin hydrolysation products; as dispersing agents there are suitable: for example lignin-sulphite waste liquors and methylcellulose.

Adhesive such as carboxymethylcellulose and natural and synthetic polymers in the form of powders, granules or latices, such as gum arabic, polyvinyl alcohol and polyvinyl actate, as well as natural phospholipids, such as cephalins and lecithins, and synthetic phospholipids, can be used in the formulations. Further additives can be mineral and vegetable oils.

It is possible to use colorants such as inorganic pigments, for example iron oxide, titanium oxide and Prussian Blue, and organic dyestuffs, such as alizarin dyestuffs, azo dyestuffs and metal phthalocyanine dyestuffs, and trace nutrients such as salts of iron, manganese, boron, copper, cobalt, molybdenum and zinc.

The formulations in general contain between 0.1 and 95 percent by weight of active compound, preferably between 0.5 and 90%.

For the mixtures come known herbicides, such as, for example, N-(2-benzothiazolyl)-N,N'-dimethyl-urea, 3-(3-chloro-4-methylphenyl)-1,1-dimethylurea, 3-(4-isopropylphenyl)-1,1-dimethylurea, 4-amino-6-(1,1-dimethyl ethyl)-3-methylthio-1,2,4-triazin-5(4H)-one, 4-amino-6-(1,1-dimethyl ethyl)-3-ethylthio-1,2,4-triazin-5(4H)-one, 1-amino-6-ethylthio-3-(2,2-dimethylpropyl)-1,3,5-triazine-2,4-(1H,3H)-dion e, 4-amino-3-methyl-6-phenyl-1,2,4-triazin-5(4H)-one, 2-chloro-4-ethylamino-6-isopropyl-amino-1,3,5-triazine, the R-enantiomer of (trimethylsilyl)-methyl 2-[4-(3,5-dichloropyridin-2-oxy)-phenoxy]-propionate, the R-enantiomer of (2-benzyloxy)-ethyl 2-[4-(3,5-dichloropyridyl-2-oxy)phenoxy]-propionate, 2,4-dichlorophenoxyacetic acid, 2-(2,4-dichlorophenoxy)-propionic acid, 4-chloro-2-methylphenoxy-acetic acid, 2-(2-methyl-4-chloro-phenoxy)-propionic acid, 3,5-diiodo-4-hydroxy-benzonitrile, 3,5-dibromo-4-hydroxy-benzonitrile and diphenyl ethers and phenylpyridazines, such as, for example, pyridates. Surprisingly some mixtures also show a synergistic action.

Mixtures with other known active compounds, such as fungicides, insecticides, acaricides, nematicides, bird repellants, plant nutrients and agents which improve soil structure, are also possible.

The active compounds can be used as such, in the form of their formulations or in the use forms prepared therefrom by further dilution, such as ready-to-use solutions, suspensions, emulsions, powders, pastes and granules. They are used in the customary manner, for example by watering, spraying, atomising or scattering.

The active compounds according to the invention can be applied either before or after emergence of the plants. They can also be incorporated into the soil before sowing.

The amount of active compound used can vary within a substantial range. It depends essentially on the nature of the desired effect. In general, the amounts used are between 0.001 and 15 kg of active compound per hectate of soil surface, preferably between 0.005 and 10 kg per ha.

The preparation and use of the active compounds according to the invention can be seen from the following examples.

PREPARATION EXAMPLES

PAC EXAMPLE 1 ##STR51##

(Process (a))

A mixture of 21.9 g (0.05 mole) of the compound of the following structural formula ##STR52## with 4 g (0.1 mole) of sodium hydroxide, 50 ml of water and 50 ml of dioxane is heated at 40°C for 2 hours.

The mixture is then acidified with concentrated hydrochloric acid and the solution is concentrated to about half. The product obtained as crystals is filtered off with suction and dried. 12.5 g (54% of theory) of 1-(2-benzyloxyaminosulphonylphenylsulphonyl)-3-(4,6-dimethylpyrimidin-2-yl )-urea of melting point 186°C (decomposition) are obtained.

EXAMPLE 2 ##STR53##

PAC (Process (b))

14 g (0.05 mole) of benzene-1,2-disulphonic acid dichloride are added in portions to a mixture of 13.6 g (0.05 mole) of N'-(4,6-dimethylpyrimidin-2-yl)-N"-benzyloxyguanidine, 12 g (0.15 mole) of pyridine and 200 ml of methylene chloride at -20°C The mixture is subsequently stirred at -20°C for 3 hours and at +20°C for 15 hours.

10 ml of water are then added to the reaction mixture and the mixture is stirred at 20°C for a further 2 hours.

The methylene chloride solution is then washed with dilute hydrochloric acid and water and concentrated. The residue is triturated with ethanol; the product obtained as crystals is isolated by filtration with suction.

6.2 g (27% of theory) of 1-(2-benzyloxyaminosulphonylphenylsulphonyl)-3-(4,6-dimethylpyrimidin-2-yl )urea of melting point 188°C (decomposition) are obtained.

The compounds of the formula (I) listed in the following Table 2 can also be prepared by the process described by way of example in the preceding Examples 1 and 2: ##STR54##

TABLE 2
__________________________________________________________________________
Example                             Melting
No.  R1         R2
R3      point (°C)
__________________________________________________________________________
3    CH2CHCH2
H
182 (decomp.)
4    C8 H17 (n)
H
##STR55##   145
##STR56##      H
##STR57##
6
##STR58##      H
##STR59##
7
##STR60##      H
##STR61##
8
##STR62##      H
##STR63##
9
##STR64##      H
##STR65##
10   CH2COOC2 H5
H
##STR66##
11
##STR67##      H
##STR68##
12   CH2 CH(CH3)2
H
##STR69##
13   CH3        CH3
##STR70##
14   CH3        H
##STR71##   194-195
15   C2 H5 H
##STR72##
16   CH2CHCH2
H
##STR73##
17
##STR74##      H
##STR75##
18   CH2 COOC2 H5
H
##STR76##
19   CH2 CH(CH3)2
H
##STR77##
20   CH3        H
##STR78##
21   CH3        H
##STR79##   218 (decomp.)
22   C2 H5 H
##STR80##
23   C3 H7 H
##STR81##
24   CH2CHCH2
H
##STR82##
25   CH2 CH(CH 3)2
H
##STR83##
26
##STR84##      H
##STR85##
27   CH3        H
##STR86##
28   CH3        H
##STR87##
29   C2 H5 H
##STR88##
30   CH3        H
##STR89##
31    CH3       H
##STR90##
32   CH3        H
##STR91##
33   CH3        H
##STR92##
34   CH3        H
##STR93##
35   C2 H5 H
##STR94##
36   C3 H7 H
##STR95##
37   CH2CHCH2
H
##STR96##
38   CH2 CH(CH3)2
H
##STR97##
39
##STR98##      H
##STR99##
40   C4 H9 H
##STR100##
41   CH3        H
##STR101##
##STR102##
42   C2 H5 H
##STR103##
##STR104##
43   CH3        H
##STR105##
44   CH3        H
##STR106##
45   CH3        H
##STR107##
46
##STR108##     H
##STR109##
47   CH 3       H
##STR110##
48   CH3        H
##STR111##
49   C2 H5 H
##STR112##  218
50   C3 H7 (n)
H
##STR113##  212 (decomp.)
51   C3 H7 (i)
H
##STR114##  218 (decomp.)
52   C4 H9 (n)
H
##STR115##  109
53   CH3        H
##STR116##  218
__________________________________________________________________________

Preparation of the starting compounds of the formula (II)

PAC EXAMPLE (II-1) ##STR117##

14 g (0.05 mole) of benzene-1,2-disulphonic acid dichloride are added in portions to a mixture of 13.6 g (0.05 mole) of N'-(4,6-dimethylpyrimidin-2-yl)-N"-benzyloxy-guanidine, 12 g (0.15 mole) of pyridine and 100 ml of methylene chloride at -20°C The mixture is subsequently stirred at -20°C for 3 hours and at +20° C. for 15 hours. The reaction mixture is then evaporated and 70 ml of dioxane are added to the residue. The mixture is filtered. The filtrate is concentrated, the residue is triturated with ethanol and the product which has precipitated is isolated by filtration with suction.

15 g (68% of theory) of the compound of the above-mentioned structural formula of melting point 199°C are obtained.

The compounds of the formula (II) listed in the following Table 3 can be prepared by the process described by way of example in the preceding example: ##STR118##

TABLE 3
__________________________________________________________________________
Example                               Melting
No.  R1         R2
R3      point (°C.)
__________________________________________________________________________
(II-2)
CH2CHCH2
H
180 (decomp.)
(II-3)
C8 H17 (-n)
H
##STR119##  164
(II-4)
CH2COOC2 H5
H
##STR120##  210 (decomp.)
(II-5)
##STR121##     H
##STR122##
(II-6)
##STR123##     H
##STR124##
(II-7)
##STR125##     H
##STR126##
(II-8)
##STR127##     H
##STR128##
(II-9)
##STR129##     H
##STR130##
(II-10)
##STR131##     H
##STR132##
(II-11)
CH2CH(CH3)2
H
##STR133##  amorphous
(II-12)
CH3        CH3
##STR134##
(II-13)
CH3        C2 H5
##STR135##
(II-14)
CH3        H
##STR136##
(II-15)
CH2 CH(CH3)2
H
##STR137##
(II-16)
##STR138##     H
##STR139##
(II-17)
CH2COOC2 H5
H
##STR140##
(II-18)
CH3        H
##STR141##  151 (decomp.)
(II-19)
C2 H5 H
##STR142##
(II-20)
C3 H7 H
##STR143##
(II-21)
CH2CHCH2
H
##STR144##
(II-22)
CH2 CH(CH3)2
H
##STR145##
(II-23)
##STR146##     H
##STR147##
(II-24)
CH3        H
##STR148##
(II-25)
CH3        H
##STR149##
(II-26)
CH3        H
##STR150##
(II-27)
CH3        H
##STR151##
(II-28)
CH3        H
##STR152##
(II-29)
CH3        H
##STR153##
(II-30)
CH3        H
##STR154##
(II-31)
CH3        H
##STR155##
(II-32)
CH3        H
##STR156##
(II-33)
C2 H5 H
##STR157##
(II-34)
C3 H7 (-n)
H
##STR158##
(II-35)
C4 H9 (-n)
H
##STR159##
(II-36)
##STR160##     H
##STR161##
(II-37)
CH2CHCH2
H
##STR162##
(II-38)
CH2 CH(CH3)2
H
##STR163##
(II-39)
CH3        H
##STR164##
(II-40)
##STR165##     H
##STR166##
(II-41)
CH3        H
##STR167##
(II-42)
CH3        H
##STR168##
(II-43)
CH3        H
##STR169##
(II-44)
CH2 CH(CH3)2
H
##STR170##
(II-45)
CH3        H
##STR171##
(II-46)
CH3        H
##STR172##  158
(II-47)
C2 H5 H
##STR173##  104
(II-48)
C3 H7 (-n)
H
##STR174##  134
(II-49)
C4 H9 (-n)
H
##STR175##  179
(II-50)
CH3        H
##STR176##  187
__________________________________________________________________________

Preparation of the starting substances of the formula (IV)

PAC EXAMPLE (IV-1) ##STR177##

A mixture of 143 g (0.97 mole) of 2-cyanoamino-4,6-dimethyl-pyrimidine, 94.3 g (1.06 moles) of O-sec.-butyl-hydroxylamine and 190 ml of ethanol is heated at the boiling point under reflux for 6 hours. The mixture is then filtered with suction, the filtrate is concentrated and 500 ml of water are added to the residue. The product thereby obtained as crystals is isolated by filtration with suction.

131 g (57% of theory) of N'-(4,6-dimethyl-pyrimidin-2-yl)-N"-sec.-butoxy-guanidine of melting point 78°C are obtained.

The compounds of the formula (IV) listed in the following Table 4 can be prepared analogously: ##STR178##

TABLE 4
__________________________________________________________________________
Example                               Melting point
No.  R1         R2
R3      (°C.)
__________________________________________________________________________
(IV-2)
H
##STR179##  85-86
(IV-3)
##STR180##     H
##STR181##  102-103
(IV-4)
##STR182##     H
##STR183##  170-172
(IV-5)
##STR184##     H
##STR185##  n D24.5 = 1.5776
(IV-6)
CH2CHCH2
H
##STR186##  103
(IV-7)
C8 H17 (n)
H
##STR187##  58
(IV-8)
CH2COOC2 H5
H
##STR188##  98"99
(IV-9)
##STR189##     H
##STR190##  147-148
(IV-10)
CH3        CH3
##STR191##  95
(IV-11)
CH2 CH(CH3)2
H
##STR192##  52
(IV-12)
##STR193##     H
##STR194##  189-192 (decomp.)
(IV-13)
CH2 CH2 CH2 Cl
H
##STR195##  137
(IV-14)
CH2 COOCH3
H
##STR196##  148-149
(IV-15)
##STR197##     H
##STR198##  114-116
(IV-16)
##STR199##     H
##STR200##
(IV-17)
##STR201##     H
##STR202##
(IV-18)
CH2CON(CH3)2
H
##STR203##
(IV-19)
CH2 OCH3
H
##STR204##
(IV-20)
CH2 SCH3
H
##STR205##
(IV-21)
##STR206##     H
##STR207##  138
(IV-22)
CH2 CH2 OCH3
H
##STR208##
(IV-23)
CH2 CF3
H
##STR209##
(IV-24)
##STR210##     H
##STR211##  152
(IV-25)
##STR212##     H
##STR213##  102
(IV-26)
CH2COOCH(CH3)2
H
##STR214##  112
(IV-27)
CH3        H
##STR215##  152
(IV-28)
C2 H5 H
##STR216##  95
(IV-29)
C3 H7 (n)
H
##STR217##
(IV-30)
CH(CH3)2
H
##STR218##
(IV-31)
C4 H9 (n)
H
##STR219##
(IV-32)
CH2 CH(CH3)2
H
##STR220##
(IV-33)
CH2CHCH2
H
##STR221##
(IV-34)
##STR222##     H
##STR223##  150
(IV-35)
CH2COOC2 H5
H
##STR224##
(IV-36)
CH3        H
##STR225##  98
(IV-37)
CH3        H
##STR226##  126
(IV-38)
##STR227##     H
##STR228##  (amorphous)
(IV-39)
C2 H5 H
##STR229##  (amorphous)
(IV-40)
C3 H7 H
##STR230##
(IV-41)
CH2 CH(CH3)2
H
##STR231##
(IV-42)
CH2CHCH2
H
##STR232##
(IV-43)
CH3        H
##STR233##
(IV-44)
CH3        CH3
##STR234##  135
(IV-45)
CH3        C2 H5
##STR235##
(IV-46)
CH3        H
##STR236##  112
(IV-47)
##STR237##     H
##STR238##
(IV-48)
CH3        H
##STR239##
(IV-49)
CH3        H
##STR240##
(IV-50)
CH3        H
##STR241##
(IV-51)
CH3        H
##STR242##
(IV-52)
CH3        H
##STR243##  122
(IV-53)
C2 H5 H
##STR244##
(IV-54)
C3 H7 H
##STR245##
(IV-55)
C4 H9 H
##STR246##
(IV-56)
CH2 CH(CH3)2
H
##STR247##  76
(IV-57)
##STR248##     H
##STR249##  68
(IV-58)
##STR250##     H
##STR251##  74
(IV-59)
CH2COOC2 H5
H
##STR252##
(IV-60)
CH3        H
##STR253##
(IV-61)
CH3        H
##STR254##  107-109
(IV-62)
CH3        H
##STR255##
(IV-63)
##STR256##     H
##STR257##  112
(IV-64)
CH(C6 H5)2
H
##STR258##  165
(IV-65)
##STR259##     H
##STR260##  130
__________________________________________________________________________

Preparation of the starting substances of the formula (V)

PAC EXAMPLE (V-1) ##STR261##

A mixture of 42 g (0.5 mole) of cyanoguanidine ("dicyandiamide") and 50 g (0.5 mole) of 2,4-pentanedione ("acetylacetone") is heated at 120° C. for 15 hours. After cooling, 500 ml of water are then added to the reaction mixture and the solution is acidified with hydrochloric acid at 0°C to 10°C The product thereby obtained as crystals is isolated by filtration with suction. 51.8 g (70% of theory) of 2-cyanoamino-4,6-dimethyl-pyrimidine of melting point 205°C are obtained.

EXAMPLE (V-2) ##STR262##

A solution, heated to 100°C, of 24 g (0.427 mole) of potassium hydroxide in 100 ml of water is added to a mixture of 9.2 g (0.043 mole) of 4,6-dimethoxypyrimidin-2-yl-thiourea and 70 ml of water at 100° C., with stirring. The mixture is subsequently stirred at 100°C for 2 minutes and a solution, warmed to 100°C, of 16.2 g (0.05 mole) of lead-II acetate in 30 ml of water is then added. The mixture is heated under reflux for a further 5 minutes and then cooled to 0° C. to 5°C, and 30 ml of glacial acetic acid are added to the aqueous solution. The product thereby obtained as crystals is isolated by filtration with suction.

6.3 g (81.5% of theory) of 2-cyanoamino-4,6-dimethoxy-pyrimidine of melting point 202°C are obtained.

The compounds of the formula (V) listed in the following Table 5 can be prepared by the process described by way of example in the preceding example: ##STR263##

TABLE 5
______________________________________
Example                         Melting
No.    R2 R3          point (°C.)
______________________________________
(V-3)  H
203 (decomp.)
(V-4)  H
##STR264##      234
(V-5)  H
##STR265##      258
(V-6)  H
##STR266##
(V-7)  H
##STR267##      200
(V-8)  H
##STR268##
(V-9)  H
##STR269##
(V-10) H
##STR270##
(V-11) H
##STR271##
(V-12) H
##STR272##      174
(V-13) H
##STR273##      174
(V-14) H
##STR274##      146
(V-15) H
##STR275##      >300
(V-16) H
##STR276##      126
(V-17) H
##STR277##      186
______________________________________

2-(Alkyl-cyano-amino)-pyrimidines of the formula (V) can be prepared, for example, as follows:

EXAMPLE (V-18) ##STR278##

12.6 g (0.1 mole) of dimethyl sulphate are added dropwise to a solution of 15 g (0.1 mole) of 2-cyanoamino-4-hydroxy-6-methyl-pyrimidine and 4.1 g (0.1 mole) of sodium hydroxide in 60 ml of water, whereupon the reaction temperature rises from 20°C to 40°C After the mixture has been stirred at 20°C for two hours, the product obtained as crystals is isolated by filtration with suction.

11.1 g (68% of theory) of 2-(methyl-cyano-amino)-4-hydroxy-6-methyl-pyrimide of melting point 290°C are obtained.

The following compound is obtained analogously:

EXAMPLE (V-19) ##STR279##

Melting point: 215°C to 220°C

(EXAMPLE (V-20) ##STR280##

127.5 g (1 mole) of dimethyl sulphate are added dropwise to a solution of 75 g (0.5 mole) of 2-cyanoamino-4-hydroxy-6-methyl-pyrimidine--prepared according to process (b)--and 44 g (1.1 moles) of sodium hydroxide in 750 ml of water, whereupon the reaction temperature rises from 20°C to 35°C After the mixture has been stirred at 20°C for twelve hours, the pH value is brought to between 9 and 10 by addition of sodium hydroxide solution and the product obtained as crystals is isolated by filtration with suction.

13 g (15% of theory) of 2-(methyl-cyanoamino)-4-methoxy-6-methyl-pyrimidine of melting point 123°C are obtained.

The following compounds are obtained analogously:

EXAMPLE (V-21) ##STR281##

Melting point: 104°C

EXAMPLE (V-22) ##STR282##

Melting point: 71°C

Preparation of the starting substances of the formula (XI)

PAC EXAMPLE (XI-1) ##STR283##

A mixture of 15.5 g (0.1 mole) of 2-amino-4,6-dimethoxy-pyrimidine, 13.1 g (0.1 mole) of ethoxycarbonyl isothiocyanate and 200 ml of acetonitrile is stirred at 60°C for 2 hours. It is then cooled at 10°C and the product obtained as crystals is isolated by filtration with suction.

22.5 g (79% of theory) of 1-(ethoxycarbonyl)-3-(4,6-dimethoxy-pyrimidin-2-yl)-thiourea of melting point 194°C (decomposition) are obtained.

The compounds of the formula (XI) listed in the following Table 6 can be prepared by the process described by way of example in the preceding example: ##STR284##

TABLE 6
______________________________________
Example                            Melting
No.     R7    R3         point (°C.)
______________________________________
(XI-2)
##STR285##     189
(XI-3)
##STR286##
##STR287##     198-9 (decomp.)
(XI-4)  OC2 H5
##STR288##     217
(XI-5)
##STR289##
##STR290##     190
(XI-6)  OC2 H5
##STR291##     140
(XI-7)
##STR292##
##STR293##     145
(XI-8)
##STR294##
##STR295##     161
(XI-9)  OC2 H5
##STR296##     119
(XI-10)
##STR297##
##STR298##     182
(XI-11) OC2 H5
##STR299##     184-185
(XI-12) OC2 H5
##STR300##     173
(XI-13) OC2 H5
##STR301##     160-162
(XI-14) OC2 H5
##STR302##     132-136
(XI-15) OC2 H5
##STR303##     169
(XI-16)
##STR304##
##STR305##     156
(XI-17) OC2 H5
##STR306##
(XI-18) OC2 H5
##STR307##
(XI-19)
##STR308##
##STR309##
(XI-20) OC 2 H5
##STR310##     168
(XI-21) OC2 H5
##STR311##
(XI-22)
##STR312##
##STR313##
(XI-23) OC2 H5
##STR314##
(XI-24)
##STR315##
##STR316##
(XI-25) OC2 H5
##STR317##
(XI-26)
##STR318##
##STR319##
(XI-27) OC2 H5
##STR320##
(XI-28)
##STR321##
##STR322##     173
(XI-29)
##STR323##
##STR324##     179
______________________________________

Preparation of the starting substances of the formula (XII)

PAC EXAMPLE (XII-1) ##STR325##

A mixture of 5.0 g (0.0175 mole) of 1-(ethoxycarbonyl)-3-(4,6-dimethoxy-pyrimidin-2-yl)-thiourea, 4.0 g (0.1 mole) of sodium hydroxide and 100 ml of water is stirred at 20°C for 2 days. Dilute hydrochloric acid is then added dropwise, with stirring, until the solution has been rendered acid and the evolution of CO₂ has ended. The product obtained as crystals is isolated by filtration with suction.

3.5 g (94% of theory) of 4,6-dimethoxy-pyrimidin-2-yl-thiourea of melting point 245°-8°C (decomposition) are obtained.

The compounds of the formula (XII) listed in the following Table 7 can be prepared by the process described by way of example in the preceding example: ##STR326##

TABLE 7
______________________________________
Example                     Melting
No.      R3            point (°C.)
______________________________________
(XII-2)
264-265 (decomp.)
(XII-3)
##STR327##        231 (decomp.)
(XII-4)
##STR328##        259-260 (decomp.)
(XII-5)
##STR329##        214-215
##STR330##
(XII-6)
##STR331##        192-194
(XII-7)
##STR332##
(XII-8)
##STR333##        225-227 (decomp.)
(XII-9)
##STR334##
(XII-10)
##STR335##
(XII-11)
##STR336##        156
(XII-12)
##STR337##
(XII-13)
##STR338##
(XII-14)
##STR339##        263
(XII-15)
##STR340##        166
(XII-16)
##STR341##        248
______________________________________

EXAMPLE A

Pre-emergence test

Solvent: 5 parts by weight of acetone

Emulsifier: 1 part by weight of alkylaryl polyglycol ether

To produce a suitable preparation of active compound, 1 part by weight of active compound is mixed with the stated amount of solvent, the stated amount of emulsifier is added and the concentrate is diluted with water to the desired concentration.

Seeds of the test plants are sown in normal soil and, after 24 hours, watered with the preparation of the active compound. It is expedient to keep constant the amount of water per unit area. The concentration of the active compound in the preparation is no importance, only the amount of active compound applied per unit area being decisive. After three weeks, the degree of damage to the plants is rated in % damage in comparison to the development of the untreated control. The figures denote:

0%=no action (like untreated control)

100%=total destruction

In this test, the active compounds according to the invention exhibit a very good herbicidal activity.

EXAMPLE B

Pre-emergence test

Solvent: 5 parts by weight of acetone

Emulsifier: 1 part by weight of alkylaryl polyglycol ether

To produce a suitable preparation of active compound, 1 part by weight of active compound is mixed with the stated amount of solvent, the stated amount of emulsifier is added and the concentrate is diluted with water to the desired concentration.

Test plants which have a height of 5-15 cm are sprayed with the preparation of the active compound in such a way as to apply the particular amount of active compound desired per unit area. The concentration of the spray liquor is so chosen that the particular amounts of active compound desired are applied in 2,000 l of water/ha. After three weeks, the degree of damage to the plants is rated in % damage in comparison to the development of the untreated control. The figures denote:

0%=no action (like untreated control)

100%=total destruction

In this test, the active compounds according to the invention exhibit a very good herbicidal activity.

Claims

1. A 1-(2-oxyaminosulphonylphenylsulphonyl)-3-heteroaryl-urea of the formula ##STR342## in which R¹ represents c₁ -c₁2 -alkyl which is optionally substituted by fluorine, chlorine, cyano, c₁ -c₄ -alkoxy, c₁ -c₄ -alkylthio, c₁ -c₄ -alkylsulphinyl, c₁ -c₄ -alkylsulphonyl, c₁ -c₄ -alkyl-carbonyl, c₁ -c₄ -alkoxy-carbonyl, c₁ -c₄ -alkylamino-carbonyl or di-(c₁ -c_d4 -alkyl)(c₁ -c₄ -alkyl)-amino-carbonyl, or represents c₃ -c₆ -alkenyl which is optionally substituted by fluorine, chlorine or bromine, c₃ -c₆ -alkinyl, c₃ -c₆ -cycloalkyl, c₃ -c₆ -cycloalkyl-c₁ -c₂ -alkyl or phenyl-c₁ -c₂ -alkyl which is optionally substituted by fluorine, chlorine, nitro, cyano, c₁ -c₄ -alkyl, c₁ -c₄ -alkoxy or c₁ -c₄ -alkoxy-carbonyl, or represents benzhydryl, or represents phenyl which is optionally substituted by fluorine, chlorine, nitro, cyano, c₁ -c₄ -alkyl, trifluoromethyl, c₁ -c₄ -alkoxy, c₁ -c₂ -fluoroalkoxy, c₁ -c₄ -alkylthio, trifluoromethylthio or c₁ -c₄ -alkoxy-carbonyl,

R² represents hydrogen or c₁ -c₄ -alkyl which is optionally substituted by fluorine, chlorine, cyano, c₁ -c₄ -alkoxy, c₁ -c₄ -alkylthio, c₁ -c₄ -alkylsulphinyl, c₁ -c₄ -alkylsulphonyl, c₁ -c₄ -alkyl-carbonyl, c₁ -c₄ -alkoxy-carbonyl, c₁ -c₄ -alkylamino-carbonyl or di-(c₁ -c₄ -alkyl)-aminocarbonyl, or represents c₃ -c₆ -alkenyl, c₃ -c₆ -alkinyl or phenyl-c₁ -c₂ -alkyl which is optionally substituted by fluorine, chlorine, nitro, cyano, c₁ -c₄ -alkyl, c₁ -c₄ -alkoxy or c₁ -c₄ -alkoxycarbonyl,

R⁴ represents hydrogen, fluorine, chlorine, bromine, hydroxyl, c₁ -c₄ -alkyl which is optionally substituted by fluorine and/or chlorine, c₁ -c₄ -alkoxy which is optionally substituted by fluorine and/or chlorine, c₁ -c₄ -alkylthio which is optionally substituted by fluorine and/or chlorine, amino, c₁ -c₄ -alkylamino or di-(c₁ -c₄ -alkyl)-amino,

X represents nitrogen,

Y represents an optionally substituted methine bridge c-R⁵,

R⁵ represents hydrogen, fluorine, chlorine, bromine, cyano, formyl, c₁ -c₄ -alkyl, c₁ -c₃ -alkoxy-carbonyl or c₁ -c₃ -alkyl-carbonyl, and

Z represents an optionally substituted methine bridge c-R⁶, and

R⁶ represents hydrogen, fluorine, chlorine, bromine, hydroxyl, c₁ -c₄ -alkyl which is optionally substituted by fluorine and/or chlorine, c₁ -c₄ -alkylthio which is optionally substituted by fluorine and/or chlorine, amino, c₁ -c₄ -alkylamino or di-(c₁ -c₄ -alkyl)-amino.

2. A compound according to claim 1, in which

R¹ represents c₁ -c₈ -alkyl which is optionally substituted by fluorine or chlorine, c₃ -c₄ -alkenyl, c₁ -c₂ -alkoxy-carbonmethyl, phenyl, phenethyl or benzyl which is optionally substituted by fluorine, chlorine, nitro, cyano, methyl, methoxy or methoxy-carbonyl,

R² represents hydrogen,

R⁴ represents chlorine, methyl, ethyl, methoxy, di-fluoromethoxy or ethoxy,

X represents nitrogen,

Y represents a methine bridge (CH) and

Z represents an optionally substituted methine bridge c-R⁶, and

R⁶ represents hydrogen, chlorine, methoxy, ethoxy, methylthio, ethylthio, dimethlamino dimethylamino or diethylamino.

3. A compound according to claim 1, wherein such compound is 1-(2-methoxyaminosulphonyl-phenylsulphonyl)-3-(4-methoxy-6-methyl-pyrimidi n-2-yl)-urea of the formula ##STR343##

4. A compound according to claim 1, wherein such compound is 1-(2-methoxyaminosulphonyl-phenylsulphonyl)-3-(4-chloro-6-methoxy-pyrimidi n-2-yl)-urea of the formula ##STR344##

5. A compound according to claim 1, wherein such compound is 1-(2-methoxyaminosulphonyl-phenylsulphonyl)-3-(4,6-dimethoxy-pyrimidin-2-y l)-urea of the formula ##STR345##

6. A compound according to claim 1, wherein such compound is 1-(2-ethoxyaminosulphonyl-phenylsulphonyl)-3-(4-methoxy-6-methyl-pyrimidin -2-yl)-urea of the formula ##STR346##

7. A compound according to claim 1, wherein such compound is 1-(2-methoxyaminosulphonyl-phenylsulphonyl)-3-(4-ethoxy-6-methyl-pyrimidin -2-yl)-urea of the formula ##STR347##

8. A compound according to claim 1, wherein such compound is 1-(2-allyloxyaminosulphonyl-phenylsulphonyl)-3-(4,6-dimethoxy-pyrimidin-2- yl)-urea of the formula ##STR348##

9. A herbicidal composition comprising a herbicidally effective amount of a compound according to claim 1 and a diluent.

10. A method of combating unwanted vegetation which comprises applying to such vegetation or to a locus from which it is desired to exclude such vegetation a herbicidally effective amount of a compound according to claim 1 and a diluent.

11. The method according to claim 10, wherein such compound is

1-(2-methoxyaminosulphonyl-phenylsulphonyl)-3-(4-methoxy-6-methyl-pyrimidin -2-yl)-urea,

1-(2-methoxyaminosulphonyl-phenylsulphonyl)-3-(4-chloro-6-methoxy-pyrimidin -2-yl)-urea,

1-(2-methoxyaminosulphonyl-phenylsulphonyl)-3-(4,6-dimethoxy-pyrimidin-2-yl )-urea,

1-(2-ethoxyaminosulphonyl-phenylsulphonyl)-3-(4-methoxy-6-methyl-pyrimidin- 2-yl)-urea,

1-(2-methoxyaminosulphonyl-phenylsulphonyl)-3-(4-ethoxy-6-methyl-pyrimidin- 2-yl)-urea, or

1-(2-allyloxyaminosulphonyl-phenylsulphonyl)-3-(4,6-dimethoxy-pyrimidin-2-y l)-urea.