Phenoxysulfonylureas based on 3-substituted alkyl salicylates, and their use as herbicides and plant growth regulators

Compounds of the formula (I) or salts thereof ##STR1## in which R.sup.1 is (C.sub.1 -C.sub.4)alkyl, R.sup.2 is halogen, methoxy, ethyl or propyl, R.sup.3 is hydrogen or methyl, E is CH or N and R.sup.4 and R.sup.5 independently of one another are halogen, (C.sub.1 -C.sub.4)alkyl, (C.sub.1 -C.sub.4)alkoxy or (C.sub.1 -C.sub.4)alkylthio, the abovementioned alkyl-containing radicals being unsubstituted or substituted by one or more halogen atoms or one or two (C.sub.1 -C.sub.4)alkoxy or (C.sub.1 -C.sub.4)alkylthio groups, have an excellent herbicidal action against a large number of harmful plants and also growth-regulatory properties on plants.

DESCRIPTION 
It is known that phenoxysulfonylureas containing heterocyclic substituents 
have herbicidal and plant growth-regulating properties (EP-A-4,163, 
DE-A-3,151,450, DE-A-3,725,939 (ZA-88/5725) and German Patent Application 
P-3,816,704.2 (EP-A-0,342,569, and ZA-89/3643)). 
EP-A-4,163 thus describes, inter alia, 2-methoxyphenoxy-, 2-chlorophenoxy- 
and 2-alkylphenoxy- as well as 2-carbomethoxy-phenoxysulfonylureas having 
a herbicidal action. 
Surprisingly, it has now been found that combinations of the carbomethoxy 
substituents with in each case one of the other radicals mentioned leads 
to a considerable improvement in the herbicidal properties. 
The present invention thus relates to compounds of the formula (I) or salts 
thereof 
##STR2## 
in which R.sup.1 is (C.sub.1 -C.sub.4) alkyl, 
R.sup.2 is halogen, methoxy, ethyl or propyl, 
R.sup.3 is hydrogen or methyl, 
E is CH or N and 
R.sup.4 and R.sup.5 independently of one another are halogen, (C.sub.1 
-C.sub.4) alkyl, (C.sub.1 -C.sub.4) alkoxy or (C.sub.1 -C.sub.4) 
alkylthio, the abovementioned alkyl-containing radicals being 
unsubstituted or substituted by one or more halogen atoms or one or more 
(C.sub.1 -C.sub.4)alkoxy or (C.sub.1 -C.sub.4)alkylthio groups. 
Halogen is fluorine, chlorine, bromine and/or iodine, preferably fluorine, 
chlorine and/or bromine, in particular fluorine or chlorine. 
(C.sub.1 -C.sub.4)alkyl and the corresponding alkyl radical in the 
alkyl-containing radicals, such as alkoxy or alkylthio, is methyl, ethyl, 
n-propyl, i-propyl, n-butyl, i-butyl, t-butyl or 2-butyl. 
The compounds of the formula I can form salts in which the hydrogen of the 
--SO.sub.2 --NH group is replaced by a cation suitable for agriculture. 
These salts are in general metal salts, in particular alkali metal or 
alkaline earth metal salts, and if appropriate inorganic or organic 
ammonium salts. 
Preferred compounds of the formula I or salts thereof are those in which 
R.sup.1 is methyl or ethyl, E is a group of the formula CH and R.sup.4 and 
R.sup.5 independently of one another are chlorine, bromine, (C.sub.1 
-C.sub.2)alkyl or (C.sub.1 -C.sub.4)alkoxy, it being possible for the 
abovementioned alkyl-containing radicals to be substituted by one or more 
fluorine or chlorine atoms. 
Particularly preferred compounds of the formula I or salts thereof are 
those in which R.sup.1 is methyl or ethyl, E is a group of the formula CH 
and R.sup.4 and R.sup.5 independently of one another are chlorine, 
(C.sub.1 -C.sub.2)alkyl or (C.sub.1 -C.sub.2)alkoxy, it being possible for 
the abovementioned alkyl-containing radicals to be substituted by one or 
more fluorine or chlorine atoms. 
The present invention furthermore relates to processes for the preparation 
of the compounds of the general formula I or salts thereof, which comprise 
a) reacting a compound of the formula (II) 
##STR3## 
with a compound of the formula (III) 
##STR4## 
or 
b) reacting a compound of the formula (IV) 
##STR5## 
with a chlorosulfonylurea of the formula (V) 
##STR6## 
or 
c) reacting a compound of the formula (VI) 
##STR7## 
with a carbamate of the formula (VII) 
##STR8## 
in which Z is phenyl or (C.sub.1 -C.sub.6) alkyl, and if appropriate 
converting the resulting compounds of the formula (I) into their salts. 
The reaction of the compounds of the formulae (II) and (II) is preferably 
carried out in inert aprotic solvents, such as, for example, acetonitrile, 
methylene chloride, toluene, chlorobenzene, tetrahydrofuran or dioxane,, 
at temperatures between 0.degree. C and the boiling point of the solvent. 
The phenoxysulfonyl isocyanates of the formula (II) can be prepared in a 
simple manner by processes which are known in principle from the 
corresponding salicylic acid esters of the formula (IV) and chlorosulfonyl 
isocyanate (c.f. G. Lohaus, Chem. Ber. 105, 2791 (1972)). 
The starting substances of the formula (III) are known or can be prepared 
by processes which are known in principle, for example by cyclization of 
corresponding guanidine derivatives with correspondingly substituted 
1,3-diketones, c.f., for example, "The Chemistry of Heterocyclic 
Compounds". Vol. XVI (1962) and Supplement I (1970), or by derivatization 
of cyanuric chloride, c.f., for example, "The Chemistry of Heterocyclic 
Compounds", L. Rapaport: "s-Triazines and Derivatives" (1959)). 
The reaction of the compounds of the formula (IV) with the 
chlorosulfonylureas of the formula (V) is preferably carried out in inert 
solvents, such as, for example, methylene chloride, tetrahydrofuran, 
dioxane or dimethoxyethane, at temperatures between -10.degree. C. and 
80.degree. C. in the presence of a base as the HCl-binding agent. Bases 
which can be employed are alkali metal carbonates or bicarbonates and 
alkaline earth metal carbonates or bicarbonates, such as, for example, 
K.sub.2 CO.sub.3 NaHCO.sub.3 and Na.sub.2 CO.sub.3 or tertiary amines, 
such as, for example, pyridine or triethylamine. 
The salicylic acid eaters of the formula (IV) are known from the literature 
or can be prepared by processes which are known from the literature. The 
chlorogulfonylureas of the formula (V) are accessible from the amines of 
the formula (III) and chlorosulfonyl isocyanate (EP-A 141,199). 
The reaction of the compounds of the formula (VI) with the heterocyclic 
carbamates of the formula (VII) is preferably carried out in the presence 
of tertiary organic bases such as, for example, 
1,8-diazabicyclo[5.4.0]-undec-7-ene (DBU) in inert solvents, such as 
acetonitrile or dioxane, at temperatures between 20.degree. C. and the 
boiling point of the solvent (analogously to EP-A 44,807). 
The carbamates of the formula (VII) required for this reaction are known 
from the literature or are prepared by known processes (EP-A 70,,804). The 
sulfamates of the formula (VI) are prepared by known processes from the 
salicylic acid esters on which they are based (c.f., for example, 
Synthesis 1978, 357; Z. Chem. 15, 270 (1975) and Chem. Ber. M , 2791 
(1972)). 
The salts of the compounds of the formula (I) are preferably prepared in 
inert solvents, such as, for example, water, methanol or acetone, at 
temperatures of 0.degree.-100.degree. C. Examples of suitable bases for 
the preparation of the salts according to the invention are alkali metal 
carbonates, such as potassium carbonate, alkali metal and alkaline earth 
metal hydroxides, ammonia or ethanolamine. 
The compounds of the formula I according to the invention have an excellent 
herbicidal activity against a broad spectrum of economically important 
mono- and dicotyledon harmful plants. Even perennial weeds which are 
difficult to combat and shoot from rhizomes, rootstock or other permanent 
organs are readily affected by the active compounds. It is irrelevant here 
whether the substances are applied by the pre-sowing, pre-emergence or 
post-emergence method. Some representatives of the mono- and dicotyledon 
weed flora which can be controlled by the compounds according to the 
invention may be mentioned as examples, without the list representing a 
limitation to certain species. 
On the part of monocotyledon weed species,, examples which are readily 
affected are Avena, Lolium, Alopecurus, Phalaris, Echinochloa, Digitaria, 
Setaria and the like, as well as Cyperus species from the annual group, 
and on the part of perennial species Agropyron, Cynodon, Imperata and 
Sorghum and the like, and also perennial Cyperus species. 
In the case of dicotyledon weed species, the action spectrum extends to 
Galium, Viola, Veronica, Lamium, Stellaria, Amaranthus, Sinapis, Ipomoea, 
Matricaria, Abutilon, Sida and the like on the annual side, and 
Convolvulus, Cirsium, Rumex, Artemisia and the like amongst the perennial 
weeds. 
Weeds which occur under the specific crop conditions in rice, such as, for 
example, Sagittaria, Alisma, Eleocharis, Scirpus, Cyperus and the like, 
are also controlled outstandingly well by the active compounds according 
to the invention. 
If the compounds according to the invention are applied to the soil surface 
before germination, either emergence of the weed seedlings is prevented 
completely, or the weeds grow to the cotyledon stage, but then stop 
growing and finally die completely after a period of three to four weeks. 
If the active compounds are applied to the green parts of plants by the 
post-emergence process, a drastic stop in growth likewise occurs very 
rapidly after the treatment, and the weed plants remain in the growth 
stage which existed at the time of application, or die more or less 
rapidly after a certain period of time, so that weed competition which is 
damaging to the crop plants can in this way be eliminated very early and 
in a lasting manner by using the novel agents according to the invention. 
Although the compounds according to the invention have an excellent 
herbicidal activity against mono- and dicotyledon weeds, crop plants of 
economically important crops, such as, for example, wheat, barley, rye, 
rice, maize, sugar beet, cotton and soya, are harmed only insignificantly, 
if at all. For these reasons, the present compounds are particularly 
suitable for selectively controlling undesirable plant growth in 
agricultural crop plantations. 
The compounds according to the invention moreover exhibit growth-regulatory 
properties in crop plants. They intervene in a regulating manner in the 
endogenous metabolism of the plant and can therefore be employed for 
facilitating harvesting, such as, for example, by inducing desiccation, 
abscission and growth compression. They are moreover also suitable for the 
general control and inhibition of undesirable vegetative growth, without 
at the same time killing the plants. An inhibition of vegetative growth is 
of great importance in many mono-and dicotyledon crops, since lodging can 
in this way be reduced or completely prevented. 
The compounds of the formula (I) can be formulated in various ways, 
according to the biological and/or chemicophysical parameters which exist. 
Examples of suitable formulation possibilities are: wettable powders (wp), 
emulsifiable concentrations (EC) and aqueous solutions (SL); emulsions, 
sprayable solutions, oil- or water-based dispersions (SC), suspoemulsions, 
dusting agents (DP), dressing agents, granules (GR), such as soil or 
scattering granules (FG) or water-dispersible granules (WG), ULV 
formulations, microcapsules or waxes. 
These individual types of formulations are known in principle and are 
described, for example, in: Winnacker-Kuchler, "Chemische Technologie 
(Chemical Technology)" Vol. 7, C. Hauser Verlag Munich, 4th Edition, 1986; 
van Falenkenberg, "Pesticides Formulations", Marcel Dekker, N.Y., 2nd 
Edition, 1972-73; and K. Martens, "Spray Drying Handbook", 3rd Edition, 
1979, G. Goodwin Ltd., London. 
The formulation auxiliaries required, such as inert materials, surfactants, 
solvents and other additives, are likewise known and are described, for 
example, in: "Handbook of Insecticide Dust Diluents and Carriers", 2nd 
Edition, Darland Books, Caldwell N.J.; H. V. Olphen, "Introduction to Clay 
Colloid Chemistry"; 2nd Edition, J. Wiley & Sons, N.Y.; Marschen, 
"Solvents Guide", 2nd Edition, Interscience, N.Y., 1950; McCutcheon's 
"Detergents and Emulsifiers Annual", MC Publ. Corp., Ridgewood N.J.; 
Sisley and Wood, "Encyclopedia of Surface Active Agents", Chem. Publ. Co. 
Inc., N.Y., 1964; Schonfeldt, "Grenzflachenaktive Athylenoxidaddukte 
(Surface-active ethylene oxide adducts)", Wiss. Verlagsgesell., Stuttgart 
1976; Winnacker-Kuchler, "Chemische Technologie (Chemical Technology)", 
Volume 7, C. Hauser Verlag Munich, 4th Edition, 1986. 
Wettable powders are preparations which are uniformly dispersible in water 
and which, in addition to the active compounds, and if appropriate in 
addition to a diluent or inert substance, also contain wetting agents, for 
example polyoxyethylated alkylphenole, polyoxyethylated fatty alcohols and 
fatty amines, alkane sulfonates or alkylaryl sulfonates, such as 
alkylbenzenesulfonates, and dispersing agents, for example sodium 
ligninsulfonate, sodium 2,2'-dinaphthylmethane-6,6"-disulfonate, sodium 
dibutylnaphthalenesulfonate or sodium oleoyl-methyl-taurate. They are 
prepared in the customary manner, for example by grinding and mixing the 
components. 
Emulsifiable concentrates can be prepared, for example, by dissolving the 
active compound in an inert organic solvent, for example butanol, 
cyclohexanone, dimethylformamide, xylene or higher-boiling aromatics or 
hydrocarbons, with the addition of one or more emulsifiers. If the active 
compounds are liquid, all or some of the solvent content can also be 
dispensed with. Examples of emulsifiers which can be used are: calcium 
alkylarylsulfonates, such as Ca dodecylbenzenesulfonate, or nonionic 
emulsifiers, such as fatty acid polyglycol esters, alkyl-aryl polyglycol 
ethers, fatty alcohol polyglycol ethers, propylene oxide-ethylene oxide 
condensation products, fatty alcohol-propylene oxide-ethylene oxide 
condensation products, alkyl polyglycol ethers, sorbitan fatty acid 
esters, polyoxyethylene sorbitan fatty acid esters or polyoxyethylene 
sorbitol esters. 
Dusting agents can be obtained by grinding the active compound with finely 
divided solid substances, for example talc or natural clays, such as 
kaolin, bentonite, pyrophyllite or diatomaceous earth. 
Granules can be prepared either by spraying the active compound on to an 
absorbent granular inert material or by applying active compound 
concentrates to the surface of carriers, such as sand or kaolinites, or of 
granular inert material by means of binders, for example polyvinyl 
alcohol, sodium polyacrylate or mineral oils. Suitable active compounds 
can also be granulated in the manner customary for the preparation of 
fertilizer granules, if desired as a mixture with fertilizers. 
The agrochemical formulations as customary contain 0.1 to 99% by weight, in 
particular 2 to 95% by weight, of active compound of the formula (I). The 
concentrations of the active compound can vary here, depending on the type 
of formulation. 
In wettable powders, the active compound concentration is, for example, 
about 10 to 90% by weight, the remainder to make up to 100% by weight 
consisting of customary formulation constituents. In emulsifiable 
concentrates, the active compound concentration can be about 5 to 80% by 
weight. Dust-like formulations usually contain 5 to 20% by weight, and 
sprayable solutions about 2 to 20% by weight. In granules, the active 
compound content depends in part on whether the active compound is in 
liquid or solid form and on what granulation auxiliaries, fillers and the 
like are used. 
In addition, the active compound formulations mentioned contain, if 
appropriate, the particular customary adhesives, wetting agents, 
dispersing agents, emulsifiers, penetration agents, solvents, fillers or 
carriers is or mixtures thereof. 
The invention thus also relates to herbicidal and plant growth-regulating 
agents which contain a compound of the formula (I) or salts thereof and 
customary formulation auxiliaries which are inert under the storage 
conditions. 
For use, the concentrates in the commercially available form are diluted, 
if appropriate, in the customary manner, for example by means of water in 
the case of wettable powders, emulsifiable concentrates, dispersions and 
in some cases also microgranules. Dust-like and granular formulations and 
sprayable solutions are usually not diluted further with additional inert 
substances before use. 
The application amount required varies in accordance with the external 
conditions, such as temperature, humidity and the like. It can vary within 
wide limits, for example between 0.005 and 10.0 kg/ha or more of active 
substance, but is preferably between 0.01 and 5 kg/ha. 
Mixtures or mixed formulations with other active compounds, such as, for 
example, insecticides, acaricides, herbicides, fertilizers, growth 
regulators or fungicides, are also possible if appropriate. 
The invention is explained in more detail by the following Examples.