Note: Descriptions are shown in the official language in which they were submitted.
~23~7~
Field Of The Invention
This inventlon relates to herbicidally active sulfamoyl urea
derivatives, including herbicidal formulations uses thereof to control
the growth of noxlous plants, i.e., weeds.
Descri~tion Of The Invention
This invention concerns sulfamoyl urea derivatives represented
by the Formula I:
I.
NHS02-N / B
R2 R5 _
wherein: Z is N or CH;
~'
~235~02
R and R2 are the same or different and represent
halogen or Cl to C6 alkyl, substituted
alkyl or alkoxy;
R3 and R4 are the same or different and represent
hydrogen, Cl to C4 alkyl, alkoxyalkyl,
haloalkyl, or up to C3 alkenyl or alkynyl;
R5 is hydrogen, halogen, or Cl to C4 alkyl or haloalkyl; and
R6 is methyl or ethyl.
Preferred compounds within the scope of this lnvention are
those wherein Z is nitrogen, R is lower alkyl, e.g., methyl; R is
lower alkoxy, e.g., methoxy; R3, R4 and R5 are hydrogen; and R
is methyl.
The Formula I compounds may conveniently be prepared in a
two-step reaction, involving reacting in the first step a suitably
substituted amino pyrimidine or amino triazine of the Formula II:
II.
Rl
t
~ N \ H
R
wherein Rl, R2, R3 and Z are as previously defined, with a
halosulfonyl isocyanate of the formula OCN~S02-Hal, wherein Hal is
halogen, e.g., chlorine, fluorine or bromine to form the corresponding
halosulfonyl urea of the Formula III:
-- 2 --
oz
III. Rl
~ 3
R ~
In the second step, the Formula III compsund is reacted,
prePerably in the presence of an acid acceptor, e.g. triethylamine, with
at least a stoichiometric amount of a suitably substituted amine of the
Formula IV:
IV.
H - ~ ~
~ ~ - R6
R5 ~
wherein R4, R5 and R6 are as previously defined, to form a Formula
I compound of the invention.
Ths invention is further illustrated by the following Examples
which describe preparation of certain compounds of this invention.
The following Examples are illustrative of the preparation of
certain preferred compounds of this invention.
Example I
Preparation of: 1-(2-methylcarbonylphenylsulfamoyl)-
3-(4-methyl-6-methoxy-1,3,5-triazin-2-yl)urea
To a stirred solution of 0.01 mole of chlorosulfonyl isocyanate
in methylene chloride maintained at 0-5C. via an ice bath was added 1.4
~2357()2
grams (0.01 mole) of 2-amino-4-methyl-6-methoxy-1,3,i-triazine. After
two hours reaction time, a methylene chloride solution containing 1.35
grams (0.01 mole) of o-amino acetophenone and l.O gram (O.Ol mole) of
triethylamine is added dropwise. The reaction mixture was stirred
rapidly while in the ice bath and was then removed and allowed to warm to
room temperature. After standing overnight, the reaction mixture was
poured into aqueous sodium carbonate. The aqueous layer was washed once
with chloroform and filtered. Acidification with dilute aqueous
hydrochloric acid resulted in a white precipitate which after suction
filtration and vacuum drying afforded 2.4 grams of material confirmed by
NMR analysis as the desired product.
Example II
Preparation of: 1 (2-methylcarbonyl-4~fluorophenylsulfamoyl)-3-
(4-methyl-6-methoxy-1,3,5-triaæin-2-yl)urea
To 75 milliliters of methylene chloride maintained at 0-5C via
an ice bath were added 1.4 grams of 4-methyl-6-methoxy-2-amino-1,3,5-
triazine and 1.55 grams of chlorosulfonyl isocyanate. After stirring for
2 hours at ice bath temperature a methylene chloride solution containing
1.0 gram of trie~hylamine and 1.53 grams of 5-fluoro-2-amino-acetophenone
was added dropwise. The stirred reaction mixture was permitted to warm
to room temperature and was then shaken once with 2 percent aqueous
hydrochloric acid then twice with water. Removal of solvent afforded a
crystalline solid which was washed with a small amount of diethyl ether.
Suction drying afforded light tan crystals identified by NMR analysis as
the desired product.
35'~02
Example III
Preparation of: 1-(2-methylcarbonyl)-4-chloro-
phenylsulfamoyl)-3-(4-methyl-6-methoxy-l~3~5-triazin-2-yl)urea
To 75 milliliters of methylene chloride maintained at 0-5C.
via an ice bath were added 1.4 grams of 4-methyl-~-methoxy-
2-amino-1,3,5-triazine and 1.55 grams of chlorosulfonyl isocyanate.
After stirring for 2 hours at ice bath temperature a methylene chlorlde
solution containing 1.0 gram of triethylamine and 1.7 grams of
5-chloro-2-aminoace~ophenone was added dropwise. The stirred reaction
mixture was permitted to warm to room temperature and was then shaken
with cold, dilute aqueous hydrochloric acid solution. After phase
separation, the organic layer was drawn-off, washed with water and
evaporated affording a brown pasty residue. The residue was dissolved in
5 milliliters of methylene chloride. Diethyl ether was added and
precipitation was initiated by scratching the flask. The crystalline
precipitate was isolated by filtration, washed with diethyl ether and
suction dried, sffording 2.8 grams of white crystals confirmed by NMR
analysis to be the desired product.
Although the invention has been illustrated by the foregoing
Examples with regard to the preparation of certain compounds within the
scope of Formula I, it is to be understood that other compounds within
the scope of Formula I may readily be prepared by those skilled in the
art simply by varying the choice of starting materials and using the same
or similar te~hniques.
Weed control in accordance with this invention is effected by
applying to the soil prior to emergence of weeds therefrom or to the
plant surfaces subsequent to emergence from the soil, a herbicidally
effective amount of a compound of this invention. It is, of course, to
123~70~
be understood that the term "a compound of this invention" also includes
mixtures of such compounds or a formulation containing a compound or
mixture of compounds of this invention.
The term "herbicidally effective amount" is that amount of a
compound of this invention required to so injure or damage weeds such
that the weeds are incapable of recovering following application while
not causing substantial injury to any valuable crop amongst which the
weeds might be growing. The quantity of a compound of this invention
applied in order to exhibit a satisfactory herbicidal effect may vary
over a wide range and depends on a variety of factors, such as, for
example, hardiness of a particular weed species, extent of weed
infestation, climatic conditions, soil conditions, method of application,
and the like. Typically, as little as one or less pound per acre of a
compound of this invention would be expected to provide satisfactory weed
control, although in some instances application rates in excess of one
pound per acre, e.g., up to S or more pounds per acre might be required.
Of course, the efficacy of a particular compound agains~ a particular
weed species may readily be determined by routine laboratory or field
testing in a manner well known to the art. It is expected that
satisfactory weed control can be had at a rate of application in the
range of 0.1 to 2.0 pounds per acre.
Of course, a compound of this invention can be formulated
according to routine methods with any of several known and commonly used
herbicidal diluents, adjuvants and carriers. The formulations can con-
tain liquid carriers and adjuvants and carriers. The formulations can
contain liquid carriers and adjuvants such as organic solvents, as well
as emulsifiers, stabilizers, dispersants, suspending agents, spreaders,
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~23570Z
penetrants, wetting agents and the like. Typical carriers utilized in
dry formulations include clay, talc, diatomaceous earth, silica and the
like. Preferred formulations are those in the form of wettable powders,
flowables, dispersible granulates or aqueous emulsifiable concentrates
which can be diluted with water at the site of applicaeion. Also, dry
formulatlons such as granules, dusts, and the like, may be used.
When desired~ a compound of this invention can be applied in
combination with other herbicidal agents in an effort to achieve even
broader vegetative control. Typical herbicides which can be conveniently
combined with Formula I compound include atrazine, hexazinone,
metribuzin, ametryn, cyanazine, cyprazine, prometon, prometryn,
propazine, simazine, terbutryn, propham, alachlor, acifluorfen, bentazon~
metolachlor and N,N-dialkyl thiocarbamates such as ~PTC, butylate or
vernolate. These, as well as other herbicides described, for example, in
the Herbicide Handbook of the Weed Science Society of America, may be
used in combination with a compound or compounds of the invention. Typi-
cally such formulations will contain from about 5 to about 95 percent by
weight of a compound of this inventionO
The herbicidal formulations contemplated herein can be applied
by any of several method known to the art. Generally, the formulation
will be surfaced applied as an aqueous spray. Such application can be
carried out by conventional ground equipment, or if desired, the sprays
can be aerially applied. Soil incorporation of such surface applied her-
bicides is accompllshed by natural leaching, and is of course facilitated
by natural rainfall and melting snow. If desired, however, the
herbicides can be incorporated into the soil by conventional tillage
means.
123S'702
Compounds of this invention are believed effective for
preemergence or postemergence control of a wide variety of broadleaf and
grassy weeds. Typical of the varlous species of vegetative growth that
may be controlled, combated, or eliminated are, for example, annuals such
as pigweed, lambsquarters, foxtail, crabgrass, wild mustard, field
pennycress, ryegrass, goose grass, chickweed, wild oats, velvetleaf,
purslane, barnyardgrass, smartweed, knotweed, cocklebur, kochia, medic,
ragweed, hemp nettle, spurrey, pondweed, carpetweed, morningglory,
ducksalad, cheatgrass, fall panicum, jimsonweed, witchgrass, watergrass,
wild turnip, and similar annual grasses and weeds. Blennials that may be
controlled include wild barley, campion, burdock, bull thistle,
roundleaved mallow, purple star thistle, and the like. Also controlled
by the compounds of this invention are perennials such as quackgrass,
Johnsongrass, Canada thistle, curly dock, field chickweed, dandelion,
Russian knapweed aster, horsetail, ironweed, sesbania, cattail,
wintercress, horsenettle, nutsedge, milkweed, sicklepod, and the like.
The compounds prepared as described in the Examples were
individually screened for herbicidal efficacy, against a variety of
broadleaf and grassy weed species, under controlled laboratory conditions
of light, humidity and temperature. Solvent solutions of said compounds
were applied, both preemergence and postemergence, to test flats
containing the various weed species, and herbicidal efficacy was
determined by periodic visual inspection, afeer application of the
compounds. Herbicidal efficacy was determined on a Numerical Injury
Rating (NIR) scale of from O (no injury) to 10 (all plants dead). A NIR
rating of 7-9 indicates severe injury; a NIR rating of 4-6 indicates
moderate injury, i.e., plant growth is reduced to the extent that normal
-- 8 --
~2~Q2
growth would be expected only under ideal conditions; and a NIR rating of
1-3 indicates slight injury.
For example, the following table gives the average preemergence
and/or postemergence NIR determined for each of the compounds prepared as
described in Examples I through III on the broadleaf (BL) and grassy (GR)
weed species to which the compounds were applied. Each compound was
applied at the indicated rate of application in pounds per acre and the
NIR was determined three weeks subsequent to application.
I II III
Pre-BL 9.0 6.3 8.3
Pre-GR 9.0 9.0 8.2
Post-BL 6.6 7.2 6.7
Post-GR 8.2 3.0 3.3
Rate 0.5 2 2
The broadleaf weeds used in the screening tests were
coffeeweed, jimsonweed, tall morningglory, wild mustard, teaweed and
velvetleaf. The grassy weeds used in the screening tests were
barnyardgrass, large crabgrass, Johnsongrass, wild oats and yellow
foxtail. In additio~ to the above observed herbicidal activities the
compounds were found very effective, especially when applied
preemergence, in controlling yellow nutsedge, a very difficult weed to
control.
Although the invention has been described in considerable
detail by the foregoing, it is to be understood that many variations may
be made therein by those skilled in the art without departing from the
splrit and scope thereof as defined by the appended claims.
