[0001] This invention relates to novel herbicidal compounds having the formula

in which R
1 is alkyl, lower alkenyl, chloro-lower alkyl, lower cycloalkyl, lower alkoxy, thio-lower
alkyl, or

R
2 is hydrogen, lower alkoxyalkyl or lower alkanoyl; R
3 and R
4 are independently hydrogen, lower alkyl or lower alkoxy; X and Y are independently
chloro, fluoro or bromo; Z is hydrogen, methyl, dimethyl, or one methyl and one chloro
substituent; and n is 0 or 1, provided that if n is 1, R
1 is alkyl and R
2-is hydrogen, then R
1 is an alkyl group having from 1 to 4 carbon atoms.
[0002] By the term "alkyl" is meant such groups having from 1 to 10, preferably from 1 to
6 carbon atoms, including both straight chain and branched chain groups. Examples
of alkyl groups are methyl, ethyl, n-propyl, isopropyl, butyl, 1-methylbutyl, and
1,1-dimethylbutyl groups.
[0003] By the terms "lower alkyl", "chloro-lower alkyl", "lower alkoxy", "thio-lower alkyl",
"lower alkoxyalkyl" and "lower alkanoyl" are meant such groups having from 1 to 4
carbon atoms. Examples of such groups are methyl, ethyl, isopropyl, n-butyl, methoxy,
isopropoxy, α-chloroethyl, thioethyl, ethoxymethyl, propionyl, and the like.
[0004] By the term "lower alkenyl" is meant such groups having from 2 to 4 carbon atoms,
for example, propenyl and isopropenyl.
[0005] By the term "lower cycloalkyl" is meant such groups having from 3 to 5 carbon atoms.
A preferred member of this group is cyclopropyl.
[0006] In one embodiment of this invention, the compounds are ureas; that is R
1 is

. In another embodiment, R
1 is alkyl, lower alkenyl, chloro-lower alkyl or lower cycloalkyl; the compounds are
mono-amides; if R
1 is lower alkoxy the compounds are carbamates; if R
1 is thio-lower alkyl, they are thiocarbamates. If R
1 is as defined in the previous sentence, the nitrogen-containing group is referred
to as the "amide moiety". If R
i is an amide moiety and R
2 is lower alkanoyl, the compounds are imides. R
2 is preferably hydrogen.
[0007] In one embodiment of the invention, the amide or urea moiety and the halo-substituted
cyclopropylmethoxy moiety are substituted on the phenyl ring in the meta position
with respect, to each other. In another embodiment the two moieties are substituted
on the phenyl ring in the para position with respect to each other. In a third embodiment
the two moieties are substituted on the phenyl ring in the para position with respect
to each other and a mono-chloro group is substituted on the phenyl ring in the ortho
position with respect to the cyclopropylmethoxy substituent. This embodiment includes
many of the most active compounds of this invention.
[0008] In another embodiment of the invention, X and Y are both chloro. In yet another embodiment
of the invention, X is chloro and Y is bromo or fluoro. In still another embodiment
of the invention, X and Y are both chloro and Z is 1-methyl. In another embodiment
of the invention, Z is 3-chloro, 3-methyl.
[0009] The compounds of this invention have been found, in general, to be active herbicides;
that is, they have been found to be herbicidally effective against various weeds.
Weeds, in the broadest sense are plants which grow in locations in which they are
not desired. The compounds of this invention have varied herbicidal activities; that
is, the effect of the compounds on weeds differs according to the structure, with
regard to pre- and post-emergence activity and grassy versus broadleafed plant response,
as well as varied responses between species. In general, the compounds of this invention
show at best only moderate general activity as pre-emergence herbicides but are primarily
active as post-emergence herbicides at rates of application of up to about 8 pounds
per acre or higher. In general, as both pre-emergence and post-emergence herbicides,
the compounds are active primarily against broadleaf weeds; some of the compounds
of this invention are active against both broadleaf and grass weeds as post-emergence
herbicides.
[0010] These novel compounds may be employed as both general and selective herbicides. When
employed at high rates they can be used as total weedkillers in places when complete
or near complete destruction of vegetation is needed, for example, on railroad trackbeds,
shoulders and median strips of highways, vacant lots, etc. When used at lower rates,
the compounds may be satisfactory as selective herbicides; several of these compounds
have been shown selective control of broadleaf weeds in small grain crops such as
wheat and barley, even when applied at low rates.
[0011] It will be seen from the data given in Tables II and III that the compounds in which
R
1 is lower alkoxy or thio-lower alkyl appear to be less active as a general matter
than the corresponding alkyl compounds.
[0012] A. herbicide as used herein, means a compound which controls or modifies the growth
of plants. By the term "herbicidally effective amount" is meant an amount of the compound
which causes a modifying effect upon the growth of plants. By "plants" is meant germinant
seeds, emerging seedlings, and established vegetation, including roots and above-ground
portions. Such modifiying effects include all deviations from development, for example,
killing, retardation, defoliation, desiccation, regulation, stunting,til- lering,
stimulation, leaf burn, dwarfing, and the like.
[0013] Therefore, in another aspect, this invention relates to herbicidal compositions of
matter employing the compounds of the present invention in admixture with an inert
diluent or carrier. In another aspect, this invention relates to a method for controlling
undesirable vegetation comprising applying to the locus thereof a herbicidally effective
amount of a compound of the present invention. In a preferred embodiment of this aspect,
the compound is applied subsequent to the emergence of the undesired vegetation at
the locus.
[0014] In general, the compounds of the present invention are prepared by:
(a) reaction of a hydroxyaniline with a substituted cyclopropylmethyl halide:

The product of step (a) is then converted to the amide or urea in one or two steps.
The amide can be produced in one step by simple acylation:

To form the ureas, the product of reaction (a) is preferably first reacted with phosgene
instead of an acyl halide, to form an isocyanate, which is then reacted with an appropriate
amine or alcohol to form the urea:


The imides (R2 is lower alkanoyl) can be made from the amides by further acylation with an acyl
chloride.
[0015] The compounds in which R
2 is lower alkoxyalkyl can be made by reacting the amides with sodium hydride, followed
by reaction with a halo alkyl ether, such as chloromethyl ethyl ether.
[0016] Reaction (a) can be enhanced by the use of a phase transfer catalyst such as a quaternary
onium salt.
[0017] The following represent examples of preparation of compounds of the present invention.
Example 1
Preparation of N-3-(2',2'-dichloro-1'-methylcyclopropyl- methoxy)phenyl cyclopropanecarboxylic
acid (Compound 15 herein).
[0018] In a flask were placed 181 g. (2 moles) of methallyl chloride, 358 g. (3 moles) of
chloroform and 3 g. (0.01 mole) of tetrabutyl phosphonium chloride. There was then
added 9 moles of 50% sodium hydroxide solution, dropwise over two hours with vigorous
stirring. After the addition was complete, the reaction mixture was stirred for four
hours at 30°C. and then poured into two liters of water and extracted with methylene
chloride. Distillation at 25 mm. gave 269 g. (77% yield) of 1,1-dichloro-2-chloromethyl-2-methyl-
cyclopropane, b.p. 65-70°C.
[0019] 51 g. (0.3 mole) of the compound prepared in the previous step was placed in a flask
and mixed with 40 g. (0.37 mde) of 3-aminophenol, 60 g. (0.75 mole) of 50% sodium
hydroxide solution, 30 ml. of water and 2 g. of tetrabutylphosphonium chloride. The
reaction mixture was then heated to reflux with stirring for three hours, and then
poured into 1 liter of water and extracted with methylene chloride.The extract was
dried and methylene chloride stripped off at reduced pressure to yield 69 g. (93%)
of 3-(2,2-dichloro-1-methylcyclopropyl)methoxyaniline, a dark amber oil.
[0020] In a third flask there-were placed 2.5 g. (0.01 mole) of the compound prepared in
the previous step, together with 1.05 g . (0.01 mole) of cyclopropanecarboxylic acid
chloride, 1.01 g. (0.01 mole) of triethylamine and 25 ml. of ether. The flask was
maintained at 5
0C. during the filling with reactants. The reaction mixture was then stirred for two
hours, poured into water and extracted with ether.The ether extract was washed successively
with 1 M. hydrochloric acid and 1 M. sodium hydroxide, dried and stripped. There was
obtained 2.5 g. (% of theoretical) of the desired compound,

. The structure was confirmed by spectroscopic analyses.
Example 2
Preparation of 3-(2',2'-dichloro-1'-methyl cyclopropylmethoxy)-2-methyl propionanilide
(Compound 11 herein).
[0021] There were combined 2.5 g..(0.01 mole) 3-(2',2'-dichloro-1
1-methyl-cyclopropylmethoxy)aniline, 1.07 g. (0.01 mole) isobutyryl chloride, 1.5 ml.
10.01 mole) triethylamine and 25 ml. ether. During the mixing, the temperatur was
maintained at 0°C. The mixture was stirred for 2 hours at room temperature; water
was added and the mixture extracted with ether. The organic layer was dried and the
ether removed under reduced pressure. There was obtained 2.8 g. of the desired compound,

.
Example 3
Preparation of N,N-dimethyl-N'[3-(2",2"-dichloro-1"-methyl-
cyclopropylmethoxy)pheny17urea (Compound 6 herein).
[0022] 25 g. (0.1 mole) 3-(2',2'-dichloro-1'-methylcyclopropyl- methoxy)aniline was dissolved
in 150 ml. benzene. The solution was saturated with gaseous HC1 and 100 ml. of a 12.5%
solution of phosgene in benzene was added. The solution was refluxed for 3 hours,
then cooled. The solvent was removed under reduced pressure. To the product of this
reaction, 3-(2',2'-dichloro-1'-methylcyclopropylmethoxy)-phenyl isocyanate, 200 ml.
methylene chloride was added and gaseous dimethylamine was bubbled in for 1/2 hour.
The solution was stirred for 1/2 hour at room temperature,then the solvent was removed
under reduced pressure. The residue was slurried in a 25% solution of ether in hexane.
There was obtained 22 g. of the desired product, a white solid, m.p. 99 - 101°C.
Example 4
Preparation of N-[3-(2',2'-dichloro-1'-methylcyclopropyl- methoxylphenyl7o-isopropyl
carbamate (Compound 9 herein).
[0023] 4.1 g. (0.015 mole) 3-(2',2'-dichloro-1'-methylcyclopro- pylmethoxy)phenyl isocyanate
was dissolved in 20 ml. methylene chloride. Then, 2 g. isopropanol was added and the
solution stirred for 4 hours. The solvents were removed under reduced pressure to
yield 5 g. of the desired compound as an oil,

.
Example 5
Preparation of O-ethyl-N-3-,(2',2'-dichloro-1'-methylcyclo- propylmethoxy)phenyl carbamate
(Compound 21 herein).
[0024] A solution was formed by dissolving 6.5 g. (0.03 mole) 3-(2',2'-dichloro-1'-methylcyclopropylmethoxy)aniline,
3.2g. (0.03 mole) ethyl chloroformate and 3.1 g. (0.031 mole) triethylamine in 50
ml. benzene. The solution was refluxed for 3 hours and cooled. Methylene chloride
was added and the organic layer was washed with water, dried and evaporated. There
was obtained 8.7 g. of the desired product, nD
0 1.5113.
Example 6
Preparation of 3-(2"-chloro-2"-fluoro-1"-methylcyclopro- pylmethoa)2',2'-dimethyl
valeranilide (Compound 24 herein).
[0025] There were combined 5.0 g. (0.0226 mole) N-3-hydroxyphenyl-2,2-dimethylvaleramide,
3.15 g. (0.02 mole) 1-chloro-1-fluoro-2-chloromethyl-2-methyl cyclopropane, 2.0 g.
(0.025 mole) of a 50% caustic solution, 2 ml. water and 300 mg. tetrabutyl phosphonium
chloride. The mixture was refluxed for 2 hours; water was then added and the mixture
extracted with methylene chloride. The organic layer dried and evaporated to yield
4.2 g. of the desired product,

1.4679.
Herbicidal Screening Tests
[0027] The representative compounds in the foregoing Table I were tested as herbicides in
the following manner:
A. Pre-emergence Herbicide Screening Test:
[0028] Using an analytical balance, 20 mg. of the compound to be tested was weighed out
on a piece of glassine weighing paper. The paper and compound were placed in a 30
ml. wide- mouth bottle and 3 ml. of acetone containing 1% polyoxyethylene sorbitan
monolaurate emulsifier was added to dissolve the compound. If the material was not
soluble in acetone, another solvent such as water, alcohol or dimethylformamide (DMF)
was used instead. When DMF was used, only 0.5 ml. or less was used to dissolve the
compound and then another solvent was used to make the volume up to 3 ml. The 3 ml.
solution was sprayed uniformly on the soil contained in a polystyrene flat, 7" (17.78
cm) long, 5" (12.7 cm) wide and 2.75" (6.98 cm) deep one day after planting weed seeds
in the flat of soil. A No. 152 DeVil- biss atomizer was used to apply the spray using
compressed air at a pressure of 5 lb./sq.in. (0.35 kg/cm 2). The rate of application
was 8 lb./acre (8.98 kg/ha)- and the spray volume was 143 gal./acre (541 1/0,404 ha).
[0029] On the day preceding treatment, the flat was filled to a depth of 2" (5.08 cm) with
loamy sand oil. Seeds of seven different weed species were planted in individual rows
one species per row across the width of the flat. The seeds were covered with soil
so that they were planted at a depth of 0.5" (1.27 cm). The seeds used were those
of four grasses: hairy crabgrass (Digitaria sanguinalis), yellow foxtail (Setaria
glauca), watergrass (Echinochloa crusgalli), red oat (Avena sativa), and three broadleef
weeds: redroot pigweed (Amranthus retroflexus), Indian mustard (Brassica juncea) and
curly dock (Rumex crispus). Ample seeds were planted to give about 20 to 50 seedlings
per row after emergence depending on the size of the plants.
[0030] After treatment, the flats were placed in the green-house at a temperature of 70
to 85
0F. (21.1-29.4°C) and watered by sprinkling. Two weeks after treatment the degree of
injury or control was determined by comparison with untreated check plants of the
same age. The injury rating from 0 to 100% was recorded for each species as percent
control with 0% representing no injury and 100% representing complete kill. Results
of these tests are shown in the following Table II.

B. Post-emergence Herbicide Screening Test:
[0031] Seeds of six plant species, including three grasses: hairy crabgrass, watergrass,
red oat and three broadleaf weeds: mustard, curly dock and pinto beans (Phaseolus
vulgaris) were planted in the flats as described above for pre-emergence screening.
The flats were placed in the green house at 70 bis 85°F. (21.1-29.4
0C.) and watered daily with a sprinkler. About 10 to 14 days after planting when the
primary leaves of the bean plants were almost fully expanded and the first trifoliate
leaves were just starting to form, the plants were sprayed. The spray was prepared
byrweighing out 20 mg. of the test compound, dissolving it in 5 ml. of acetone containing
1% polyoxyethylene sorbitan monolaurate and then adding 5 ml. of water. The solution
was sprayed on the foliage using a No. 152 DeVil- biss atomizer at an air pressure
of 5 lb./sq.in. (5.62 kg/ ha.). The spray concentration was 0.2% and the rate was
8 lb./acre (8.98 kg/ha.). The spray volume was 476 gal./acre (1804 1/0.404 ha.). Results
of these tests are shown in

[0032] The compounds of the present invention are used primarily as post-emergence herbicides
and may be applied in a variety of ways at various concentrations.
[0033] In practice, the compounds are formulated with an inert carrier, utilizing methods
well known to those skilled in the art, thereby making them suitable for application
as dusts, sprays, or drenches and the like, in the form and manner required. The mixtures
can be dispersed in water with the aid of a wetting agent or they can be employed
in organic liquid compositions, oil and water, water in oil emulsions, etc., with
or without the addition of wetting, dispersing or emulsifying agents. An herbicidally
effective amount depends upon the nature of the seeds or plants to be controlled and
the rate of application may vary from 0.05 to approximately 50 pounds per acre or
0.056-56.2 kg/ha.
[0034] The phytotoxic compositions of this invention employing an herbicidally effective
amount of the compounds described herein are applied to the plants in the conventional
manner. Thus, the dust and liquid compositions can be applied to the plant by the
use of power-dusters, boom and hand sprayers and spray-dusters. The compositions can
also be applied from-airplanes as a dust or a spray because they are effective in
very low dosages. In order to modify or control growth of germinating seeds or emerging
seedlings, as a typical example, the dust and liquid compositions are applied to the
soil according to conventional methods and are distributed in the soil to a depth
of at least 1/2 inch below the soil surface. It is not necessary that the phytotoxic
compositions be admixed with the soil particles, since these compositions can be applied
merely by spraying or sprinkling the surface of the soil. The phytotoxic compositions
of this invention can also be applied by addition to irrigation water supplied to
the filled to be treated. This method of application permits the penetration of the
compositions into the soil as the water is absorbed therein. Dust compositions, granular
compositions or liquid formulations applied to the surface of the soil can be distributed
below the surface of the soil by conventional means such as discing, dragging or mixing
operations.
1. A compound having the formula

in which R
1 is alkyl, lower alkenyl, chloro-lower alkyl, lower cycloalkyl, lower alkoxy, thio-lower
alkyl, or
R2 is hydrogen, lower alkoxy-alkyl or lower alkanoyl; R3
and R4 are independently hydrogen, lower alkyl or lower
alkoxy; X and.Y are independently chloro, fluoro or bromo;
Z is hydrogen, methyl, dimethyl or one methyl and one
chloro substituent; and n is 0 or 1, provided that if n is
1 and R1 is alkyl, then R1 is an alkyl group having from 1 to 4 carbon atoms.
2. A compound according to Claim 1 in which R
1 is
3. A compound according to Claim 1 in which R1 is alkyl, lower alkenyl, chloro- lower alkyl, lower cycloalkyl,lower alkoxy, or thio-lower
alkyl.
4. A compound according to any of Claims 1-3 in which R1 is cyclopropyl.
5. A compound according to any of Claims 1-4 in which the cyclopropylmethoxy moiety
and the amide or urea moiety are substituted on the phenyl ring in the para position
with respect to each other, and n is 1.
6. A compound according to Claim 1 in which R1 is cyclopropyl, R2 is hydrogen, X and Y are each chloro, Z is 1-methyl, n is 1 and the cyclopropylmethoxy
and amide moieties are substituted on the phenyl ring in the para position with respect
to each other.
7. A compound according to Claim 1 in which R1 is isopropenyl, R2 is hydrogen, X and Y are each chloro, Z is 1-methyl, n is 1 and the cyclopropylmethoxy
and amide moieties are substituted in the para position with respect to each other.
8. A compound according to Claim 1 in which R1 is 1,1-dimethylbutyl, R2 is hydrogen, X and Y are each chloro, Z is hydrogen, n is 0 and the cyclopropylmethoxy
and amide moieties are substituted on the phenyl ring in the meta position with respect
to each other.
9. A compound according to Claim 1 in which R1 is isopropyl, R2 is hydrogen, X and Y are each chloro, Z is 1-methyl, n is 1 and the cyclopropylmethoxy
and amide moieties are substituted on the phenyl ring in the para position with respect
to each other.
10. A herbicidal composition of matter comprising a herbicidally effective amount
of a compound as defined in any of Claims 1-9 and an inert carrier or diluent.
11. A method for controlling undesirable vegetation comprising applying to said vegetation
or the locus thereof a herbicidally effective amount of a compound or composition
as defined in any of Claims 1-10.
12. A method according to Claim 11 in which the compound or composition is applied
subsequent to the emergence of the undesirable vegetation.
13. A method according to Claim 11 in which the compound or composition is applied
at a rate of 0.05 to 50 pounds per acre.
14. A method for production of a compound as defined in any of Claims 1-9 comprising
a) reacting a hydroxyaniline having the formula

with a substituted cyclopropylmethyl halide having the formula

in the presence of a base; and either:
b) reacting the product of step (a) with an acyl halide having the formula

to form an amide; or
c) reacting the product of step (a) with phosgene, and
d) reacting the product of step (c) with a compound having the formula NHR3R4 to produce a urea.