CA1206165A - Herbicidal 2-haloacetanilides - Google Patents

Abstract

Abstract of the Disclosure The disclosure herein relates to a group of N-alkyl-2-haloacetanilide compounds, herbicidal compositions containing said compounds as the active ingredient and herbicidal method of use in various crops, particularly, soybeans, cotton, peanuts, rape, bush beans, etc. The herbicides herein are particularly effective against the hard-to-kill annual weeds Texas panicum, itchgrass, wild proso millet, alexandergrass, red rice, shattercane and seedling johnsongrass.

Description

~2~6~5 Background of the Invention Field of the Invention ~his invention pertains to the field of 2-haloacetanilides and their use in the agronomic arts, e.g., as herbicides.
Description of the Prior Art The prior art relevant to this invention includes numerous disclosures of 2-haloacetanilides which may be unsubstituted or substituted with a wide variety of substituents on the anilide nitrogen atom and on the anilide ring including alkyl, alkoxy, alkoxyalkyl, halogen, etc., radicals.
As relevant to the invention compounds, which are characterized by havin~ a methyl or ethyl radical on the anilide nitrogen, an alkoxy ~radical in one ortho position and a methyl radical in the other ortho position, the closest prior art known to the inventor are U. S. Patent Numbers 3,268,584, 3,4~2,945, 3,7i3,492 and 4,152,137. The '492 and '137 patents disclose generic formulae for herbicidal compounds which broadly encompass the invention compounds. However, the only N-alkyl-substituted 2-haloacetanilide compound specifically disclosed by either of the '492 or '137 patents is propachlor, i.e., N-isopropyl-2-chloroacetanilide, a well-known commercial herbicide;
neither patent discloses any herbicidal data relative to 25 propachlor. U.S. Patent Number 2,863,752 (Re 26,961) discloses compounds of a class encompassing propachlor (not specifically named) and homologs and analogs thereof. Of the compounds within the scope of the '752 patent, propachlor was found to be the most herbicidally efficacious, hence, was developed as a commercial herbicide. Said '752 patent discloses that the compounds therein may be used at rates as low as 1.0 lb/A (1.12 kg/ha); however, as shown in Example IV the experimental data presented therein is limited to application rates of 5 lb/A (5.6 kg/ha) and 25 lb/A (28

-2- ~%~ 5 kg/ha). Additionally, N-ethyl-2-chloroacetanilide is a named species in said '752 patent; yet, U.S. Patent No.
4~137,070 discloses that that compound (Example 406 in the '070 patent) is an antidote for the herbicide EPTC.
In contrast to the foregoing '752 compounds, the compounds of this invention are highly effective selective herbicides against exceedingly hard-to-control weed species at application rates well below 1.~ lb/A, e.g., ranging to below one-sixteenth tl/16) lb/A (0.07 kg/ha) More structurally relevant to the invention compounds than propachlor or related compounds, perhaps, are compounds disclosed in said '584 and '945 patents.
In particular, Example 13 of said '584 patent aiscloses the compound N-tert-butyl-2'-methoxy-2-chloroacetanilide and Example 6~ of said '945 patent discloses the compound 2'-methoxy-6'-tert-butyl-2-chloroacetanilide. Thus, propachlor differs from the invention compounds in the type of substituent radicals in two positions, i.e., both ortho positions o~ the molecule, as well as the particular alkyl radical attached to the nitrogen atom. Said Example 13 in said '584 patent differs in the type of substituent in one ortho position, the particular alkoxy radical in the other ortho position and the particular alkyl radical attached to the nitrogen atom and said Example 67 in said '945 patent differs ~rom the invention compounds in the type of substituent attached to the nitrogen atom and the particular alkyl and alkoxy radicals, respectively, attached to the ortho positions of the anilide molecule.
U.S. Patent No. 4,146~387 discloses 2-haloacetanilide compounds which may be substituted with alkyl radicals on the nitrogen atom and in both ortho positions. The compounds of the '387 patent are described as known herbicides of the type disclosed, e.g.~ in the above-mentioned '945 and '752 patents, including propachlor.
~.

_3~ 65 The above '584 patent contains some herbicidal data relative to the above-mentioned compound having a chemical configuration most closely related to the invention compounds, and some data are presented for other homologous and analogous compounds less-closely related in chemical structure. More particularly, these most relevant references, while disclosing herbicidal activity on a variety of weeds, do not disclose any data for any compounds which are shown to additionally and/or simultaneously control the hard-to-kill annual weeds such as Texas panicum, itchgrass (raoulgrass), wild proso millet, alexandergrass, red rice, shattercane and seedling johnsongrass, while also controlling or suppressing a broad spectrum of other noxious perennial and annual weeds, e.g., yellow nutsedge, smartweed, lambsquarter, pigweed, foxtails, large crabgrass and barnyardgrass.
A highly useful and desirable property of herbicides is the ability to maintain weed control over an ex~ended period of time, the longer the better during each crop season. With many prior art herbicides, weed control is adequate only for 2 or 3 weeks, or, in some superior cases~ perhaps up to 4-6 weeks, before the chemical loses its effective phytotoxic properties.
Accordingly, one aisadvantage of most prior art herbicides is their relatively short soil longevity.
Another disadvantage of some prior art herbicides, somewhat related to soil longevity under normal weather conditions, is their susceptibility to leaching into the soil, hence, the lack of weed control persistence under heavy rainfall which inactivates many herbicides.
A further disadvantage of many prior art herbicides is limitation of their use in specified types of soil, i.e., while some herbicides are effective in soils having small amounts of organic matter, they are ineffective in other soils high in ~f~
,, organic matter or vice-versa. It is, therefore, advantageous that a herbicide be useful in all types o~
soil ranging from light organic to heavy clay and muck.
Yet another disadvantage of many prior art herbicides is the limitation to a particular effective mode of application, i.e., as a preemergence surface application or as a preplant soil incorporation mode of application. It is highly desirable to be able to apply a herbicide in any mode of application, whether by surface application or preplant incorporated.
And, finally, a disadvantage in some herbicides is the necessity to adopt and maintain special handling procedures due to the toxic nature thereof. Hence, a further desideratum is that a herbicide be safe to handle.
It is, therefore, an o~ject of this invention to provide a group of herbicidal compounds which overcome the above-mentioned disadvantages of the prior art and provide a multiplicity of advantages in a single group of herbicides.
It is an object of this invention to provide herbicides which selectively control hard-to-kill annual weeds such as Texas panicum, raoulgrass, wild proso millet, alexandergrass, red rice, shattercane and seedling johnsongrass, while also controlling or suppressing a broad spectrum of less-resistant perennial and annual weeds such as mentioned above, while maintaining crop safety in a plurality of crops including soybeans, cotton, peanuts, rape, bush beans, alfalfa and/or vegetable crops.
It is a further object of this invention to provide herbicidal effectiveness in the soil for extended periods ranging up to at least 12 weeks.
Yet another object of this invention is to provide herbicides which resist leaching and dilution due to high moisture conditions, e.g., as heavy ; rainfall.
~'' ,. . .

.~ .

-5~ 6~6~
Still another object of this invention is the provision of herbicides which are effective over a wide range of soils, e.g., ranging from light-medium organic to heavy clay and muck.
Another advantage of the herbicides of this invention is the flexibility available in the mode of application, i.e., by preemergence surface application and by preplant soil incorporation.
Finally, it is an advantage of the herbicides of this invention that they are safe and require no special handling procedures.
The above and other objects of the invention will become more apparent from the detailed description below.
1~ Summary of the Invention The present invention~relates to herbicidally active compounds, herbicidal compositions containing these compounds as active ingredients and herbicidal method of use of said compositions in various crops.
It has now been found that a selective group of 2-haloacetanilides characterized by specific combinations of alkyl radicals on the anilide nitrogen atom and in one ortho position and specific alkoxy radicals in the other ortho position possess unexpectedly superior and outstanding herbicidal properties vis-a-vis prior art herbicides, including the most-closely-related compounds of the most relevant prior art.
A primary feature of the herbicidal compositions of this invention is their ability to control a wide spectrum of weeds, including weeds controllable by current herbicides and, additionally, a plurality of weeds which, individually and/or collectively, have heretofore escaped control by a single class of known herbicides, while maintaining crop safety with respect to a plurality of crops including, particularly, soybeans, cotton, peanuts, rape, bush beans (snap beans), alfalfa and others as ' -6~ 6~
well. While prior art herbicides are useful for controlling a variety of weeds, including on occasion certain resistant weeds, the unique herbicides of this invention have been found to be capable of controlling or greatly suppressing a plurality of resistant weeds, most notably annual weeds, such as Texas panicum, itchgrass, wild proso millet (Panicum miliaceum), alexandergrass, red rice, shattercane and seedling johnsongrass, while controlling and/or suppressing other less-reslstant perennial and annual weeds.
The compounds of this invention are characterized by the formula C C 2 \ /
N

R2 ~1~ ORl ~

wherein R is methyl or ethyl;
~ Rl is a Cl_6 alkyl radical, preferably C3 5 - 25 alkyls;
R2 is methyl, ethyl or t-butyl, preferably methyl, and R3 is hydrogen or methyl in a meta position preferably hydrogen;
provided that:
When R is ethyl, Rl is n-butyl, R2 is methyl and R3 is hydrogen;
When R3 is methyl, R and R2 are also methyl and Rl is isopropyl or n-butyl;
When R3 is hydrogen and R and R2 are both methyl, Rl is ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, n-pentyl/ isopentyl, 2-methylbutyl, l-methylpentyl, 2-methylpentyl or 1,3-dimethylbutyl;

';i~

-7_ ~Z~6~5 When R2 is ethyl, R is methyl and R1 is isopropyl and When R2 is t-butyl, R and R1 are both methyl.
Preferred species of this invention are as follows:
N-methyl-2'-isopentyloxy-6'-methyl-2-chloro-acetanilide.
N-methyl-2'-n-propoxy-6'-methyl-2-chloro-acetanilide.
N-methyl-2'-n-butoxy-6'-methyl-2-chloroacet-anilide.
N-methyl-2'-sec-butoxy-6'-methyl-2-chloro-acetanilide.
N-ethyl-2'-n-butoxy-6l-methyl-2-chloroacet-anllide.
N-methyl-2'-isopropoxy-6'-methyl-2-chloro-acetanilide.
N-methyl-2'-isobutoxy-6'-methyl-2-chloroacet anilide.
N-methyl-2'-isopropoxy-6'-ethyl-2-chloroacet-anilide.
The utility of the compounds of this invention as the active ingredient in herbicidal compositions formulated therewith and the method of use thereof will be described below.
Detailed Description of the invention The compounds of this invention may be made in a variety of ways. For example, these compounds may be prepared by a process involving the N-alkylation of the anion of the appropriate secondary 2-haloacetanilide with an alkylating agent under basic conditions. The N-alkylation process is described in Examples l and 2 herein.

~61~i~

Example 1 This example describes the preparation of one preferred species, N-methyl-2 7 -n-butoxy-6'-methyl-2-chloroacetanilide. In this example dimethyl sulfate is used as the alkylating agent to prepare the N-alkyl-2-chloroacetanilide from the corresponding sec-amide anion.
2'-n-butoxy-6'-methyl-2~chloroacetanilide, 4.9 gms (0.02 mol), dimethyl sulfate 2.6 gms (0.02 mol) and 2.0 gms of triethyl benzyl ammonium, bromide were mixed in 250 ml of CH2C12 under cooling. Fifty (50) ml of 50%
NaOH were then added all at once at 15C and the mixture stirred for two hours. Water (100 ml) was added and the resultant layers separated. The organic layer was washed with water~ dried over MgS04 and evaporated by Kugelrohr. ~ clear liquid, b.p; 135C at 0.07 mm Hg was obtained in 78% yield (4.2 gms) and recrystallized upon standing to a colorless solid7 m.p. 41-42. 5Co Anal. Calc'd for C14H20CINO2 (%3: C, 62.33; H, 7,47;
Cl, 13.14 Found: C, 62.34; H, 7.49;
Cl, 13.16 The product was identified as N-methyl-2'-n-butoxy-6'-methyl-2-ch]oroacetanilide.
Example 2 To a chilled (15C) mixture of 2'-n-butoxy-6'-methyl-2-chloroacetanilide, 5.6 g (0.022 mol), diethyl sulfate, 4.0 g (0.024 mol), and 2.2 g of triethyl benzyl ammonium bromide in 250 ml of methylene chloride, was added all at once 50 ml of 50~ NaOH and the mixture was stirred for 5.0 minutes. Water (150 ml) was added, and the resulting layers separated; the organic layer was washed wi~h water, dried with MgSO4, then evaporated by Kugelrohr to give 4.1 g (66~yield~ of a clear liquid, b.p. 114C at 0.05 mm ~g.
.

. , -9- ~2~ S
Anal, Calc'd for C15H22CINO2 (%): C, 63.48; H, 7.81;
Cl, 12.49.
Found: C, 63.50; H, 7.~5;
Cl, 12.48.
The product was identified as N-ethyl-2'-n-butoxy-6'-methyl-2~chloroacetanilide.
Examples 3-19 Following substantially the same procedures, quantities of reactants and general conditions described in Examples 1 and 2, but substituting the appropriate sec-anilide to obtain the corresponding N-alkylated end product, other N-methyl-2-haloacetanilides according to the above formula were prepared; these compounds are identified in Table 1.

-10- 12~ 5 AG-1223 oo o ~r co ~ o ~ o o -~ ~ ~ o ~ ~ ~ ~ ~ u~ ~ ~r ~ ,1 ~`
co ~ oo ~ t~ ~ 1 O O C~ o ~ ~r ~ ~ -n ,l ~ r` ~D
~ ... .... ... ... ... ... ... ...
O ~ r` ~ o t--~ ~ ~--~ ~ I` ~ ~ r~ ~ ~ ~ ~ ~ t--~ ~ D ~r h ~ ~1 ~9 ~1 ~ _I ~ ~1 ~D ,1 ~D ~1 ~D .-1 n _i U~ ~
~,~
,1 ~ o co ~ er ,~ o o co ~7 ~ ~ ~ ~ _I ~ ~r ~1 ~D
,1 ~ C~ C) U ~ U ~ C~ U :r: C) u m _l o ~ ~ ~ o .
~C o u~ o u~ r~ ~ ~ ,I Ln ~ ~1 ~0 ~, ~0 00 _~O I I -~ ~ O 0 ~ 0 ~ 0 ~ 0 ~ ~
H~ _ 0~ 0~ 0~ 0~ 0 0~ 0~ 0 z z æ æ z; z æ z;
U ~ C~ ~) ~ U C~
5~ ~ ~ ~0 0 CO o C~ O
O ~ C $ ~ $
e~
U ~ C~ V

o t) ~ C~ o o o c) o a) x o I ~ c~
~ ~ 9 ~ ~ t) o ~ o I a~
~ ~ O ~ ~ O X S~ ~0 ~:3 ~ I O ~ I Ll SAI O ~ O O X ~1 ~0 ~ O I 0 ~0 ~ ~ O ~-1 0 0 O r~ ~1 0 r-l O O O ~1 ~ ~

O - ~a - ~ . ~ . ~ .. I .. ~ _ I _ ~

S~ ~ O S a) ~ ~ ~ ~ Q

æ~s ~ æ~ ~ æ~D ~ z~ ~ æ~D ~ z~ Z.9 ~

Q.
O ~ ~ ~ o X Z

-3L~ 6i5 AG-12 2 3 ~:1 ~ In a~ O ~ ~ U~ r o o~
~ ... ... ,..... ... ...
h ~D ~ ~ ~ ~ ~9 ~ ~D ~i ~D ~1 ~o ~ ~o ~1 U~ ~
u~ ~ ~ ~ O o~ ,1 ~ ~ r o~ ~ 1--~ co ,~ o~ a~ ,1 ~ ~ ~ o c~ ~ ~
... ... ... ... ... ... ... ...

w u~u ~ u m z um u c~ m o ~ m u u mu v~cc -~J
U-- o o _m o co u~ 0 ~ O ~D
. ~ o ~ ~ I O ~ O O O I Q, ~ O ~ O
P~ ~ ~ ~ o ~
O ~-; o , o ~ o o o ~ Ei ~~q ~ ~
H
O O O O O O O O
d ~1:1 Z Z Z 'Z Z Z Z Z
~n~ ~ ~ ~1 ~ ,~
~ ~ U C~ U U C~ ~ U V
E~~ I E; ~r ~`I o o ~ t'`l o :c ~ :r m m ~ m o ~ U ~ C~

, x I
~1~`3 X O ~C U O o ~ o o ~ ~ I
.C I O ~ O (~ Ql ,I X ~ ~ ~1 ~ I
J' ~ ~ ~ s o .s ~,~ ~ _l ~ I
O ~ h c~ ~ o X U
OJ O ~1 0 Q~ J I o J ~3,~ r Q '~ U ~ ~I Q ~
O - ~ ~ S ~:
N ~9 ~ N I N I ~ ~ ~ ~ N
s x o ,S ~ ~ .c ~ ~ s ~1 ~ ~ ; ~ 5 x o s ~ o o s~ ~ I-rl ~ O ~ ' ~ X ~ -o ~ ~ a) ~ o ~ o o ~ z ~ ~ z ~o ~ rz 1~ ~ Z ~ Z U~ 1~ Z ~ U Z Q V --a~
Q~
O 'I ~ ~ ~r Lr) ~D r~ co Z ~1 ~1 ~ ~ ~ ~

- L 2 ~ L~5 AG-l ~ 23 ;r ~
~ . . .
o ~ CO ,~
~4 U~
.,, ~
U~ ~ ~ o ~ ~1 I
_ ~ C) ~r co ~1 ,, ~v ,_ o l:i _~
U~
. ~ , ~o P~ ~ ~ o v m--H

O
Z;
~ ~ ~ ~1 El ~1 ~ N
O ~
E4 ~D
C~
-I O
~ O

~ l l _~
O
P' --IJ
~ I Ei~
~) ~ I
I . ., r~
I ~rl ~ ~1 ~
~X

ZQ ~

o Z , X
~3 The secondary anilides u~ ~a~s ~ ~rting materials in the above N-alkylation process are prepared by known methods, e.g., haloacetylation of the corresponding aniline. For example, the starting sec-anilide used in Example 1 was prepared as follows:
2-n-butoxy-6-methylaniline, 27.4 g tO.0153 mol), in 250 ml of methylene chloride was stirred vigorously with a 10% sodium hydroxide solution (0.25 mol) while a solution of chloroacetyl chloride, 17.4 gm (0.0154 mol), in methylene chloride was added over 30 minutes keeping the tempera-ture between 15-25C with external cooling. The reaction mixture was stirred for a further 60 minutes~ After the addition was complete, the layers separated and the methylene chloride layer washed with wa~er, dried and evaporated in vacuo to obtain 28.3 g of a white solid, ~.p. 127-128C.
Anal. Calc d for C13H18CINO2 (%): C, 61.05; H, 7.09;
Cl, 13.86.
Found: Cl 61.04; H, 7.08;
Cl, 13.86.
The product was identified as 2'-n-butoxy-6'-methyl-2-chloroacetanilide.
The secondary anilides used as starting materials in Examples 3-19 were prepared in a similar manner.
The primary amines used to prepare the above-mentioned secondary anilides may be prepared by known means, e.g., by catalytic reduction of the corresponding 2-alkoxy-6-alkyl-nitrobenæene in ethanol using platinum oxide catalyst.
As noted above, the compounds of this invention have been found to be e~fective as herbicides, particularly as pre-emergence herbicides, although post-emergence activity has also been shown. The pre-emergence tests referred to herein include both greenhouse and field tests. In the greenhouse tests, the herbicide is applied either as a surface application after planting the seeds or vegetative -:~
~ / .

propagules or by incorporation into a quantity of soil to be applied as a cover layer over the test seeds in pre-seeded test containers. In the Eield tests, the herbicide is pre-plant incorporated ("P.P.I.") into the soil, i.e., the herbicide is applied to the surface of the soil, then incorporated therein by mixing means followed by planting of the crop seeds.
The surface application test method used in the greenhouse is performed as follows:
Containers, e.g., aluminum pans typically 9.5"
x 5.25" x 2.75" (24.13 cm x 13.34 cm x 6.99 cm) or plastic pots 3.75" x 3.75" x 3" (9.53 cm x 9.53 cm x 7.62 cm3 having drain holes in the bottom, are level-filled with Ray silt loam soil then compacted to a level 15 0.5 inch (1.27 cm~ from the top of the pots. The pots are then seeded with plant species to be tested, then covered with a 0.5 inch layer of the test soil. The herbicide is then applied to the surface of the soil with a belt sprayer at 20 gal/A, 30 psi (187 1/ha, 2.11 20 kg/cm2). Each pot receives 0.25 inch (0.64 cm) water as overhead irrigation and the pots are ~hen placed on greenhouse benches for subsequent sub-irrigation as needed. As an alternative procedure, the overhead irrigati-on may be omitted. Observations o~ herbicidal effects are made about three weeks after treatment.
The herbicide treatment by soil incorporation used in greenhouse tests are as follows:
A good grade of top soil is placed in aluminum pans and compacted to a depth of three-eights to one-half inch from the top of the pan~ On the top of thesoil is placed a predetermined number of seeds or vegetative propagules of various plant species. The soil required to level fill the pans after seeding or adding vegetative propagules is weighed into a pan. The soil and a known amount of the active ingredient applied in a solvent or as a wettable powder suspension are thoroughly mixed, and used to cover the prepared O, ~

-15- ~2~
pans. After treatment, the pans are given an initial overhead irrigation of water, equivalent to one-fourtn inch (0.64 cm) rainfall, then watered by subirrigation as needed to give adequate moisture for germination and growth. As an alternative procedure, the overhead irrigation may be omitted. Observations are made about 2-3 weeks after seeding and treating.
Tables II and III summarize results of tests conducted to determine the pre-emergence herbicidal activity of the compounds of this invention; in these tests, the herbicides were applied by soil incorporation and sub-irrigation watering only; a dash (-) means that the indicated plant was not tested. The herbicidal rating was obtained by means of a fixed scale based on the percent injury of each plant species. The ratings are defined as follows:
% Control Rating _ _ 0-24 o The plant species utilized in one set of tests, the data for which are shown in Table II, are identified by letter in accordance with the following 25 legend: -A Canada Thistle E Lambsquarters I Johnsongrass B Cockelbur F Smartweed J Downy Brome C Velvetleaf G Yellow Nutsedge K Barnyardgrass D Morningglory H Quackgrass ~ i .~ `, -16~ S
Table II
Pre-Emergent Plant Species Co~pound of Example No. kg/h A B C D E F G H I J K

211.2 3 1 1 2 3 3 - 3333 5.6 30113 3 - 3 1 33 311.2 3 2 33 3 3 33333 5.6 313 2 3333233 4 11.2 32333333333 5.6 21323333333 11.2 3 2 333333333 5.6 32333333333 6 11.2 32 2 3 3333333 5.6 322033333233 7 11.2 333333 3 333 3 5.6 3123333 3 3 33 8 11.2 3 23333331 3 3 5.6 32223333333 9 11.2 30333333333 5.6 30 2 33333333 1.12202331 2 3 1 3 3 11 . 2 2 2 33333 3 333 - 5.6 31323223233 13 11.2 - 2 2 2 3 333 ~ 33 5.6 ~ 11133 2 3 - 33 14 11.2 31333233333 5.6 00233233133 11. ~ 11233333333 5.6 2012213203 3 16 11. 2 3 1 1 2 3 3 3 3 3 3 3 5.6 2000323 3 333 -17- ~2~6~6~
Table II (Cont'd) Pre-Emergent Plant Species Compound of xample No. kg/ha A B C D E F G H I ~ K
17 11.2 31102333333 5.6 30223233333 18 11.2 32333333333 5.6 32233333333 19 11.2 31223333233 5.6 30223333133 The compounds were further tested by utilizing the above procedure on the following plant species:
L Soybean R Hemp Sesbania M Sugarbeet E Lam~squarters N Wheat F Smartweed O Rice C Velvetleaf P Sorghum J Downy Brome B Cocklebur S Panicum Spp.
Q Wild Buckwheat K Barnyardgrass D Morningglory T Crabgrass The results are summarized in Table III.

-18~ ?~
Table III
Pre-Emergent Plant Species Compound of Example No. k~/ha L M N O P B Q D R E F C J S X T
1 5.6 3333333333333333 1.12 2323312233313333 0.28 0213312123303333 0.06 0111312012203333 0.01 0000001011100133 0.006 00000 - 0011000232 2 5.6 123331123331333 -1.12 023330103330333 -0.28 012220003110333 -0.06 000200003000113 -0.01 000100001000001 -

3 5.6 2333323333333333 1.12 1333322023323333 0.28 1223~3010 ~ 3303333 0.06 0111000003100333 0.01 0000301000002333 0.006 0000000001100011

4 506 2333333333323333 1.12 0223313233223333 0.2~ 02333 - 1333113333 0.06 01113 - 0010003333 0.01 0000000 - 00000123

5.6 3333323333333333 1.12 2333313333323333 0.~8 0222311133323333 0~05 0112200033312333 0.01 0000000011100133 0.006 0100000021100012

6 5.6 333332323333333 -1.12 233331222332333 -0.28 02133 ~ 112322333 -0.06 010000001310333 -.01 000100101100203 -

7 5.6 1333313333333333 1.12 0333303333323333 : 0.28 0232202223213333 : 0.06 0211110322111333 0.01 1101000110001023 ~: ~ 0.006 0000000120001022 ~' i'~i' - .

Table III (Cont'd) Pre-Emergent Plant Species Compound of Example No. kg/ha L M N O P B Q D R E F C J S K T

8 5.6 2 33331 2 333333333 1.112 0 2 2 3302 2 2 3 2 1 3333 0.28 0 2 2 33010 2 3 2 0 3333 0.06 0 1 0 2301001001 2 33 0.01 0100000013 2 0 0 1 3 3

9 5.6 33333 2 33333333 3 3 1.12 1 2 3331 2 2 2 3113333 0.28 0 1 2 2 2 0 1 3 2 3 2 1 2 2 33 0.06 0 1 2 1 1 0 0 0 2 0 2 0 0 2 33 0.01 0 1 2 0 0 0 0 0 2 1 1 0 0 0 2 3 5.6 2 2 33303333 2 33333 1.12 0 2 2 3311233 2 2 3333 0.28 0 2 1 3302 2 2 30 2 3333 0.06 0 1 0 1 2 0 0 0 3 2 0 2 3333 0.01 0100000010010003 11 5.6 1 333313333313333 1.12 0 1 2 33022 2 3303333 0.28 0 1 2 33-0113303333 0.06 - 00121000 2 3202233 0.01 0000000000000013 12 5.6 2 2 33313133313333 1.12- 0 2 33313 2 33313333 0.28 0 2333000132033 3 3 0.06 0 0 2 3302001203333 0.01 0000000020001033 13 5.6 1 23 2 32333332333 -1.12 0223312 2 3331333 -0.28 0 2230011 2 3 2 0 2 33 -0.06 0 1 1 1 0 0 0 0 1 210033 -0.01 000000000010101 -14 5.6 33333133333 2 3333 1.12 23 2 33023333 2 3333 0.2~ 22 2 2 3023 2 2 2 1 3333 0.06 0 2 1 2 1 0 1 2 1 2 2 0 2233 0.01 0 1 1 1 0 0 1 1 1 1 0 0 0 0 2 3 0.006 0 1 0 1 0 0 1 1 1 1 0 0 0 0 1 3 5.6 23333133333 2 333 3 1.12 0 2 3331 2 1 1 3203333 0.28 0 :L 1 1 1 0 1 0 0 1 1 0 3333 0.06 0 1 0 0 0 0 0 0 0 1 0 0 0 2 3 3 0.01 0 0 0 0 0 0 0 0 0 1 1 0 0 0 2 2 , ~ .

-20~
Table III (Cont'd) Pre-~mergent Plant Species Compound of Example No. kg/ha L M N O P B Q D R E F C J S K T
16 5.6 133331223331333 -1.12 022330212230333 -0.28 021330001330233 -0.06 010100003100323 -0.01 000000000000111 -17 5.6 033330113331333 -1.12 022330102220333 -0.28 021320001010333 -0.06 000100001100113 -0.01 0 0 0 0 0 - O O O O O O O O 1 -18 5.6 3333333333323333 1.12 0333200333223333 0.28 0223302023213338 0.06 0200202002303333 0~01 0200000000 - 00033 -21- ~Z~ 5 The herbicides of this invention have 'Deen found to possess unexpectedly superior properties as pre-emergence herbicides, most particularly in the selective control of the hard-to-kill annual weeds, Texas panicum, seedling johnsongrass, shattercane, alexanderyrass, wild proso millet, red rice and itchgrass, while also controlling or suppressing many other less-resistant perennial and annual weeds.
Selective control and increased suppression of the above-mentioned weeds with the invention herbicides have been found in a variety of crops including soybeans, cotton, peanuts, rape and snap beans (bush beans). Selectivity has been shown in some tests at varying rates of application in sugarbeets and garden peas; however, some crops, particularly grass crops, are usually less tolerant to the invention herbicides than are the foregoing cropsn In order to illustrate the unexpectedly superior properties of the compounds of this invention both on an absolute basis and on a relative basis, comparative tests were conducted in the greenhouse with compounds of the prior art most closely related in chemical structure to the invention compounds~ The prior art compounds are identified as follows-A. N-tert-butyl-2-methoxy-2-chloroacetanilide.
(E~ample 13, U.S. Patent No 3,268,584) B. 2'-t-butyl-6'-methoxy-2-chloroacetanilide.
(Example 67, U.S. Patent No. 3~442,945) C. N-isopropyl-2-chloroacetanilide (common name "propachlor'l~. U.S. Patent NoO 2,863l752 (Re Patent No. 26,961);
Propachlor is referenced in the above-me~tioned U.S. Patent Nos. 3,773,492 and 4,152,137 and is the activ~ ingredient in the commercial hexbicide "Ramrod~", a registered trademark of Monsanto Company.
In the discussion of data below, reference is -22- ~ 6~
made to herbicide application rates symbolized as "GR15"
and "GR85", these rates are given in kilograms per hectare Skg/ha) which are convertible into pounds per acre (lbs/A) by dividing the kg/ha rate by 1.12. GR15 defines the maximum rate of herbicide required to produce 15% or less crop injury, and GR85 defines the minimum rate required to achieve 85% inhibition of weeds. The GR15 and GR85 rates are used as a measure of potential commercial performance, it being understood, of course, that suitable commercial herbicides may exhibit greater or lesser plant injuries within reasonable limits.
A further guide to the effectiveness of a chemical as a selective herbicide is the "selectivity lS factor" ("SF") for a herbicide in given crops and weedsO
The selectivity factor is a measure of the relative degree of crop safety and weed injury and is expressed in terms of the GR15/GR85 ratio, i.e., the GR15 rate for the crop divided by the GR85 rate for the weed, both rates in kg/ha (lb/A). In the tables below, selectivity factors are shown in parenthesis following the GR85 rate for each weed; the symbol "NS" indicates "non-selective." Marginal or questionable selectivity is indicated by a dash (-); a blank space means that the indicated plant was not in the test or that the plant failed to germinate.
Since crop tolerance and weed control are inter-related, a brief discussion of this relationship in terms of selectivity factors is meaningful. In -30 general, it is desirable that crop safety factors, i.e., herbicide tolerance values, be high, since higher concentrations of herbicide are frequently desired for one reason or anothex. Conversely, it is desirable that weed contxol rates be small, i.e., the herbicide possesses high unit activity, for economical and possibly ecological reasons. ~owever, small rates of application of a herbicide may not be adequate to control certain weeds and a larger rate may be required. Hence the best herbicides are those which control the greatest number of weeds with the least amount of herbicide and provide the greatest degree of crop safety, i.e., crop tolerance. Accordingly, use is made of "selectivity factors" (defined above) to quantify the relationship between crop safety and weed control. With reference to the selectivity factors listed in the tables, the higher the numerical value, the greater selec-tivity of the herbicide for weed control in a given crop.
In a first comparative test, greenhouse pre-emergence herbicidal activity data are presented in Table IV comparing the relative efficacy of the compound of Example 1, representative compounds of this invention, with relevant compounds of the prior art, vi~., Compounds A, B and C, as selective herbicides against particular weeds commonly associated with soybeans. The test data in Table IV for all compounds was obtained under identical test conditions, i.e., soil incorporation with an initial overhead irrigation; the data represent the averages of two replicate runs for each compound; two different samples o~ the compound of Example 1 were used and the data in the table represent - the average from both test samples. The weeds used in -25 the tests herein have the following abbreviations in the tables: Texas panicum (TP), seedling johnsongrass (SJG), shattercane (~C), alexandergrass (A&), wild proso millet (WPM), fall panicum (FP), red rice (RR) and itchgrass (IG).

-~4- AC; 1223 ~ô
V I I I ~
H _ _ _ _ ~ ~ ~ O
J~

P~ I I I
~_ _ _ _ ~ ~ ~ Co . A A ~
~ ~
o ~ _ a~ ~
~ I I A A
c~
,~ ~ ~ o r-i ~1 0 D
~ J~ V
~1 ~^ ~ I I I U~
1~ ~ r~
K -- ~ ~ A
~ ~ ~ o ~ . ,V¢

~ ~ ~ o .
~) ~
o A A `~
_ ~ I I I A
tn ~ ~ c~
o ~ ~ ~ o /~ ~\ A V
U~
~ ~,, ~D .
,~ ,1 .~ i o /~ A A

u~ ~ Q
~ ~ X ~ /~

~ ~ m c~

-25- ~2~6~
Reference to the data in Table IV will sho~7 that with respect to weed control, none of the prior art compounds exhibited positive selective weed control against any weed in soybeans at the maximum rate of application, i.e., 1.12 kg/ha, but for the sole exception of Compound C against fall panicum, and even there, the selectivity factor was one-fold less than that for the compound of Example 1. In marked contrast, the compound of Example 1 selectively controlled every weed in the test at extremely low rates of application~
while maintaining soybean safety up to 0.71 kg/ha. Of particular note is the fact that the compound of Example 1 controlled seedling johnsongrass, shattercane, alexandergrass, fall panicum and itchgrass; at 0.07 kg/ha (the minimum rate used) or less and also controlled the remaining weeds, i.e., Texas panicum, wild proso mille~ and red rice a~ rates of only 0.10, 0.14 and 0.18 kg/ha, respectively.
Additional tests were conducted in the greenhouse in order to compare the relative herbicidal efficacy of prior art compounds A-C with the compounds of Examples 1, 3-5 and 8-17, representative of the invention compounds. The tests were conducted by soil incorporation of the herbicide at application rates within the range of from 0.07 to 1.12 kg/ha (0.0625-1.0 lb/A) and an initial overhead irrigation followed by subsequent subirrigation watering as needed.
Observations were made 19 days after treatment. The data from the additional tests are shown in Table V; the names of the weeds are abbreviated as in Table I~ and selectivity factors are shown in parentheses after the GR85 rates for each weed.

~3~
- 2 6 - A~1223 o o ~n ~ o o i o ~ _ O o _ _ ,i ~ ~ co co ,iu~ J
A ~ Z ~ A i i O ~ a:~ o 1`
i ~i ~ ~ ~i ~ ner In O ~
,i O O O o ,i~1 0 0 o O O o _ ~ ô o o ô ~ _ o o o o o o o ~ o ~ O ~ O ~O
oa~ r 5~
o o o o o o o o o o o o ~i~iooooooooooooo V V V Y V V V V V V V V
O O o o O , o O
ri I i I ~ ~ A A A,i A f~ r ,i A
i~ _ _ _ _ _ _ _ __ _ ~_ _ _ _ ~i ~~-i O O O O O~i 0 00 0 ~ O
A/~ V
_ ~ ô o ô ô _ o ô
o o ~ Oo~ ~ o c~ ~
A
o ,i o,i o o o o ,i i Oo , ~ ~:~ ~ i ~ V
~_ _ ~ ~ _ ~ ~ o _ o ~ w ~ _ ô
C~ ~ O O
~ ^ ~ r-lCO r--i ~ir i ~ ~ ~r1~ ~ ~i C) I I I A A ~ ~ J~ A A ~ ~ A
t~ ~i ~ 1~ ~ o )ct:~ oo~
r-i r--i~i O ~i O O O In ~i r-i~i O C) O O O O O O O O O r i A A ~ V V
_ _ _ OOO~ OOO
~D ~ O ~9 ~ ~ O O
i;~ '` Ai XX ~ ~; co ;; X 5;; oo co A
~ r5~
r-lr--i ~i OO O O O r iO O ~i O ~i ~I~i~i OO O~ C) OO OO O O O
VV VV V V
_ ~
_ o o a o ~ __ _ _ r~ ,, ,, o ~ OO O _ ~ O
' ~ ~ ~ ,O ~ O O
_ --~r i ~i~i ~ir-l C0 ~ t~i J\ A
r~ir~i~i O O O O ~i ~i U') ~i~~1 r~
~~i~i~i O O O O C~ O OC:~ O O O O
a~ A A V

lf ) ~ ~ ~i r i r~i ~i t- i ~i ~i r-l r~i ~i ~i r~i ~i L0 r-i t--i '~ ~ ~i r-i ~i r-i r~i ~i ~i --i --i --i ~Di ~1 .~i O ~i A/~ A A ~~ , A
O
~ ~i~ ~Il ~ ~n ~I r~ 1~i r i ~i 6~

O In oo n ~ r~
o o _ o o r-- t~
o o V V
o ~r r) o o _ _ o ~

ô

o o ~ o ~ r--I A
O ~
V
,~ O
Q~ ~ ~
_ _ CO ~D
U~
O O
~ ~; ~

-28~ 6~
Referring to the data in Table V, it will be noted that within the limits of the herbicide test rates, Compound A did not selectively control any of test weeds in soybeans CGmpound B only marginally selectively controlled fall panicum (not a particularly-resistant weed) and Compound C selectively controlled only fall panicum and, marginally, Texas panicum, alexandergrass and red rice. But for the sole exceptions of Compound C against fall panicum (GR~5 of 0.28 kg/ha) and Compound B against alexandergrass and fall panicum (GR85 of 1 00 kg/ha), none of the prior art compounds controlled any of the weeds in the test at less than 1.12 kg/ha (1.0 lb/A).
In sharp contrast, but for isolated instances against certain weeds, all of the invention compounds exhibited outstanding positive selective control of every weed in soybeans. In only a few instances was the selective control marginal, e.g~, that of the compounds of Examples 8 and 17 against red rice; Example 9 against wild proso millet and red rice; Example 14 against wild proso millet and Example 15 against shattercane.
Moreover, in contrast with the prior art compounds and again with the noted exceptions, all of the invention compounds controlled all-of the weeds at extremely low rates of application, ranging from no greater than 0.56 kg/ha t0.5 lb/A) downwardly to less than ~.07 kg/ha (0.0~25 lb/A) a remarkable performance in absolute terms in view of the highly-resistant nature of the weeds tested (excepting fall panicum) and particularly relative to the inability of the most relevant compounds of the prior art to control any of the test weeds, except as noted above.
Preferred compounds o~ this invention were further tested in the field to determine their selective preemergence herbicidal activity and soil longevity against the annual weeds Texas panicum, bristly starbur and Florida pusley in peanuts tFlorunner). Observations -29- ~2~ S
were made at 4, 8 and 12 weeks after treatment (WAT) by surface application of the herbicides; soil type was a Dothan sandy loam with 1.3~ organic matter; the results are shown in Table VI.

:~%~ 5 P~12~3 ~ , $U~ o, U~$

.~ ~ u~ ~ c~ c~ ~ u~ r oo LO co oo co '~ o l~ I ~ ,,,, ou~ o I I Ln Ln ~ I
~ j o ~ ~o o ~o~
.~ ~1 er ~ ~ 1~ o ~o ~1 ~ ~ I ~
P o ~ o u~ ~ ~ o ~ o In c~ O
er 00 ~

~ ooo,1 oo~u~ ooo~ ~
~I ~
~1 o~ 0~0~ oO~
~!
o ~ ~ o o ~ s) o u~
er ~ O ~ ' The data in Table VI show ~ha~ ~ eS compound of Example 2 selectively controlled all three weeds in peanuts-at rates within the range of 2.24 to 4.48 kg/ha for up t.o 12 WAT. Selective control of one or more of the test weeds was also exhibited by the compounds of Examples 1 and 3 at lesser rates for up to 12 WAT, indicating that of the three test compounds, the compound of Example 2 had the highest safety factor in peanuts under conditions of this test.
Yet other tests were conducted in the field to determine the relative efficacy of the compounds of Examples 1, 3 and 4 against wild proso millet in soybeans for a period up to 12 weeks after treatment when applied either as surface applications (SA) or pre-plant incorporated (PPI). The soil was a sandy loam with 1.7% organic matter; a 2.5 inch (6.35 cm) rainfall occurred 2 days after treatment, the results of this test are shown in Table VII.

s -32- AG~1223 ~1 oo o o o o ~ ~ ~ o 1` ~ co E~ ~

~1 ~1 ~ '` ~ ~ ~ ~ u~ ~ ~ co ~ ~n U~l ~ r~ co 1~ ~ ~` co co ~D In C

H I ~ CO O CO ~ ~ O O Lr) 1~ O CO

.~ CO
~ O CO O U~ O CO C~ 00 Cl~ O ~ O
ul U~ ~ ~ ~ co ~ ~o c~ ~o ~9 CO CO ~
O
,~, H¦ t'`l CO Lt~ t~l ~ 11~ 1~ 00 Lt~ ~r) O O
a~ ~: ~ Gl ~ I` co ~n 1` 1` c~ co oo c~ co ~
3 ~
~1 Q
H ~ :
H~ H
~ ~ O O O ~ O ~ O Co O O O O
2 ~ ~ ~ ,~ ~
~ ~1 Q ~
U~

j.~ ~ ~ ~ o co u~ ~ l`

R co ~ 1 ~ o 0 0 1` ~ a~ 1~ o L~1 :~ V~
u~ a~
O 1` 1` 0 0 L~ ~ I
, E~ ~
~ .,~
~I Ln~ oLn~o ~u~
u~
a~
~r ~D 0 ~ er ~ CO
. . . . . . . . . . . . .,~
O

O ~1 ~ ~
.. ' O S~ X X
C~ 1~

-33- ~ Z~
The data in Table VII show that a 3.36 kg/ha rate of each compound selectively controlled wild proso millet in soybeans for 3, 8 and 12 WAT in the surface applications. Thus, certain treatments of the crop with the invention compounds provided season long control of wild proso millet, since germination and emergence of this species increases progressively with the growing season. The greater degree of injury to soybeans in the PPI treatments was deemed to be due to excessively deep and uneven incorporation by the disc harrow and the rainfall occurring 2 days after treatment. In this test, the surface application treatments provided superior weed control and crop safety.
In yet another field test, the compounds of Examples 1, 3 and 4 were tested for their herbicidal activity on the very resistant annual weed seedling johnsongrass with both surface application and pre-plant incorporation herbicide treatments. This field test was conducted in a clay soil (58% clay and 3.1~ organic matter). Observations were made at 4 and 8 weeks aEter treatment; the results are shown in Table VIII.

- 34- ~ C6~ i AG 1223 ¢1 o o o co ~ ~ co ooco co oo u~ 0 C'~l ~ co co 1~ c~ ~D r--~o 1~ co co ~
0 ~ h ~f ~0 o H ~ ~ o u~ C~') ~ r~ oo o co 0 O rl ~L
~I ~ r~
a~ ~ o u~ ~ ~1 1` u~ oo o r~ 1~ o co r~ V ~ u~ bO
~ P~
.,_ ~ C~
.
.
~1 l ~ o r~
~ L) E~ U~

¢ au H ~ 00 ~ 00 ~') ~) C~l ~ CO CO O 00 E~ P~ ~ P~

o ¢1 ~ C~ ~ ~ ~ CO ~ o ~ c~
E~ ~ I ~ ~ ~ ~ ~ ~ , ~ , H ul C') ~) OO C~l CO C~l O ~') ' ) c~
I:~j t~l OC .... .... ....

'O
O X X X

C~

,~

~L2~

The compound of Example 4 selectively controlled seedling johnsongrass in soybeans at the 2.24 kg/ha for as long as ~ weeks after treatment under PPI
conditions and at the 3.36 and 4.48 kg/ha rates under surface application conditions. The compound of Example 1 selectively controlled seedling johnsongrass at the 3.36 kg/ha rate for at least 4 weeks after treatment under surface application conditions.
As indicated by data in the above tables, compounds according to this invention are suitable used under either surface application or soil incorporation treatments, the preferred treatment depending upon various factors such as soil, climate, etc.- Generally however, surface application of the herbicides are preferred over soil incorporation.
In laboratory tests to determine the resistance of the herbicide to leaching into the soil and resulting herbicidal efficacy, the compound of Example 1 was formulated in acetone and then sprayed at different concentra~ions onto a weighed amount of Ray silt loam contained in pots having filter paper covering drainage holes in the pot bottoms. The pots containing the treated soil were subjected to leaching by placing on~a turntable which rotated under two nozzle tips of a water container calibrated to deliver one inch (2.5 cm) of water per hour simulating rainfall. ~eaching rates were adjusted by varying the amount of time on the turntable. Water was delivered to the soil in the pots and allowed to percolate through the filter paper and drainage holes. The pots were then allowed to sit for three days at ambient room temperature. The treated soil in the pots was then removed, crumbled and placed as a surface layer on top of other pots containing Ray silt loam soil seeded with barnyardgrass seeds. The pots were then placed on greenhouse benches, sub-irrigated and allowed to grow for 2-3 weeks. Visual ratings of percent growth inhibition compared to control (untreated) pots and fresh weights for barnyardgrass were made 18 days after treatment and recorded; the data -36- ~2~6~
from three replications of these tests are shown in Table IX.
Table IX
- Barnyardgrass Percent Fresh Percent Compound Rate Rain Inhibition Weight of of Ex. 1 (Kg/Ha) (Cm) (Avg. of 3 replications) Controls 2.24 0 100 0 0 0.64 100 0 0 1.27 100 0 0 2.54 100 0 0 5.08 100 0 0

10.16 95 0 0 0.56 0 100 0 0 0.64 100 0 0 1.27 100 0 0 2.54 100 0 0 5.08 95 0 0 10.1695 ~ 0 0 0~14 0 100 0 0 0.64 100 0 0 1.27 100 0 0 2.54 95 0 0 5.0~ 95 0.20 3.3 10.16 ~0 0.83 14.1 The data in Table IX indicate that the compound of Example 1, representative of the invention~
compounds, was quite resistant to leaching into the soil under conditions of heavy rainfall and exhibited-no less than 90~ control of barnyardgrass at application rates as low as 0.14 kg/ha (0.125 lb/a) under 10.16 cm of rainfall.
A distinct advantage of a herbicide is its ability to function in a wide variety of soil types.
Accordingly, data is presented in Table X showing the herbicidal effect of the compounds of Examples 1 and 3 on alexandergrass (AG) and barnyardgrass (BYG) in soybeans in a wide variety of soil types and organic matter content. The herbicide treatments were applied by surface application with overhead irrigation as ;~. ', ,i,, .:~, described above; selectivity factors for the weeds are shown in parentheses after the GR85 rates for the weeds.

~2~6~5 _ C ~ .,. .. , o o o o o O
~A N U~ 1 Z--I Z;
Co ~
__ _ _ __ ____ __ ~D ~ ~r co ~ ~r q~ e~ er ~
.. . .. . .. . - ~3 :` o o o o o o ~ t`l ~J ~`I o O
00 ~ ,a ~, v U~
; C
-- O
~!1 ~ ~ O 1` o o o oo o c:~ o ~1 .. , ,, .. . -~ CO CO O
~p 00 ~1 ~ ~r ~ ~~ ~ er ~r Q
~1 ~1 r~ ~ ,~ ,1 ~ ~~ ~ ~ ~1 0 .. .. .. .. ..
V V ~ O o o o ,~ o ~ "
,~~ ~ ~ ~
~a~ ~: ~ .,, r~~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~r ~ ~ ~ , E~ ~ ~ _I ,1 ~ ~ ~ ~ r-l ~ ~ ~~1 ~1 In ~ ~ .. . .. .. .. .. Q~
_ o~ ~ y C~ U~

4~
I O
o 0 C7 tO
~I 0~ . I O .
a~ ~ I O ~ a~
s~ ~
S~
~ ~1 o r7 0 a~
O ,I t~l ~D u~ ~ t' a~ ~
5~ 0 Q~
aJ U~

: o O
C
~ O ~ ~ C) 0 1:
O ~ 0:
ul X X :~ X X F: X X ~1 X X ~I X X ~1 O X
.,, ~) ~ ~ ~ ~ o o ~ ~ ~
O ~ O
u~r~ u~ a v -39- ~6~
The data in Table X show that the invention compounds were largely insensitive to soil type. In more particular, the compound of Example 1 exhibited positive selective control of alexandergrass and barnyardgrass in soybeans in all soil in the test containing organic matter ranging from 1.0~ O.M. content in ~ay silt loam to 22.1% O.M. in Florida muck soil. Similarly, the compound of Example 3 exhibited positive selective control of the weeds in test in soybeans in all soil types, except against barnyardgrass in Florida sand (6.8% O.M.) and Florida muck. Since the compound of Example 3 did selectively control both alexandergrass and barnyardgrass in Drummer silty clay loam soil having approximately the same organic matter content as Florida sand, but a much higher clay content (37.0~) and in soils having higher O.M. and clay content as in Brazilian sandy clay loam, it is believed that the low clay content (1.8%) in the Florida sand contributed to non-selective control of barnyardgrass in that soil.
The compounds of this invention have their most important application in soybeans and peanuts.
However, selective weed control has been established in a variety of other crops as indicated in Table III
above. In yet other tests, the compound of Example 1 was also shown to be useful in snap beans and garden peas at rates up to 1.0 lb/a, in cotton, rape, carrot and red beet up to 0.5 lb/a or more and in alfalfa, flax and cabbage on the order of 0.25-0.5 lb/a.
Toxicology studies on the compounds of Examples 1, 3 and 4 have indicated the following properties:

-40~ 5 Compound o~
Toxicoloyy Example No.

, OLD50, Mg/Kg 3370 2300 2400 DLD, Mg/Kg. >2000>1000<1260 >3100<5010 ~ye irritation slightsevere moderate Skin irritation nonecorrosive corrosive The corrosive nature of the compound of Example 3 may be due to a contaminant, dimethyl sulfate, found in the preparation of the sample on which toxicology studies ~ere conducted. It is apparent that the above compounds may be safely used with the normal degree of care re~uired for compounds having the indicated toxicological properties. The indicated relative degree of safe handling characteristics for the compounds of the respective examples appears to be:
Example 1 > Example 4 > Example 3.
Therefore, it will be appreciated from the foregoing detailed description that compounds according to this invention have demonstrated unexpected and outstandingly superior herbicidal properties both absolutely and relative to the most structurally-relevant compounds of the prior art, one of which(Compound C) is a commercial herbicide. More particularly, the compounds of this invention have proven to be outstanding selective herbicides, particularly in the control of hard-to kill annual grasses in soybeans, peanuts and other crops. In more particularr compounds according to this invention exhibit outstanding control of the annual grasses Texas panicum, itchgrass, wild proso millet, alexandergrass, seedling johnsongrass, shattercane and red rice, while controlling and/or suppressing other less-resistant annual grasses and perennials, including those mentioned in Tables II and III above and others such as bristly starbur, Florida Pusley, etc, ~Z~6~6~;

The herbicidal compositions of this invention including concentrates which requi,re dilution prior to application contain at least one active ingredient and an adjuvant in liquid or solid form. The compositions are prepared by admixing the active ingredi.ent with an adjuvant including diluents, extenders, carriers and conditioning agents to provide cornpositions in the form of Einely-divided particulate solids, yranules, pellets, solutions, dispersions or emulsions. Thus the active ingredient can be used with an adjuvant such as a finely-divided solid, a liquid of organic origin, water, a wetting agent, a dispersing agent, an emulsifying agent or any suitable combination of these.
The compositions of this invention, particularly liquids and wettable powders, preferably contain as a conditioning agent one or more surface-active agents in amounts sufficient to render a given composition readily dispersible in water or in oil. The incorporation of a surface-active agent into the compositions greatly enhances their efficacy. By the term "surface-active agent" it is understood that wetting agents, dispersing agents, suspending agents and emulsifying agents are included- therein. Anionic, -42- ~206~S
cationic and non-ionic agents can be used with equal facility.
Preferred wetting agents are alkyl benzene and alkyl naphthalene sulfonates, sulfated fatty alcohols, amines or acid amides, long chain acid esters of sodium isothionate, esters of sodium sulfosuccinate, sulfated or sulfonated fatty acid esters, petroleum sulfonates, sulfonated vegetable oils, ditertiary acetylenic glycols, polyoxyethylene derivatives of alkylphenols (particularly isooctylphenol and nonylphenol) and polyoxyethylene derivatives of the mono-higher fatty acid esters of hexitol anhydrides (e.g., sorbitan).
Preferred dispersants are methyl cellulose, polyvinyl alcohol, sodium lignin sulfonates, polymeric alkyl, naphthalene sulfonates, sodium naphthalene sulfonate, and the polymethylene bisnaphthalene sulfonate.
Wettable powders are water-dispersible compositions containing one or more active ingredients, an inert solid extender and one or more wetting and dispersing agents. The inert solid extenders are usually of mineral origin such as the natural clays, diatomaceous earth and synthetic minerals derived from silica and the like. Examples of such extenders include kaolinites, attapulgite clay and synthetic magnesium silicate. The wettable powders compositions of this invention usually contain from about 0.5 to 60 parts (preferably from 5-20 parts) of active ingredient, from about 0.25 to 25 parts (preferably 1-15 parts) of wetting agent, from about 0.25 to 25 parts (preferably 30 1.0~15- parts) of dispersant and from 5 to about 95 parts (preferably 5-50 parts) of inert solid extender, all parts being by weight of the total composition. Where required, from about 0.1 to 2.0 parts of the solid inert extender can be replaced by a corrosion inhibitor of anti-foaming agent or both.
; Other formulations include dust concentrates ~2~

comprising from 0.1 to 60% by weight of the active ingredient on a suitable extender; these dusts may be diluted for application at concentrations within the range of from about 0.1-10% by weight.
Aqueous suspensions or emulsions may be prepared by stirring an aqueous mixture of a water-insoluble active ingredient and an emulsification agent until uniform and then homogenized to give stable emulsion of very finely-divided particles. The resulting concentrated aqueous suspension is characterized by its extremely small particle size, so that when diluted and sprayed, coverage is very uniform.
Suitable concentrations of these formulations contain from about 0.1-60% preferably 5-50% by weight of active ingredient, the upper limit being determined by the solubility limit of active ingre~ient in the solvent.
In another form of aqueous suspensions, a water-immiscible herbicide is encapsulated to form microencapsulated phase dispersed in an aqueous phase.
In one embodiment, minute capsules are formed by bringing together an aqueous phase con-taining a lignin sulfonate emulsifier and a water-immiscible chemical and polymethylene polyphenylisocyanate, dispersing the water-immiscible phase in the aqueous phase followed by addition of a polyfunctional amine. The isocyanate and amine compounds react to form a solid urea shell wall around particles of the water-immiscible chemical, thus forming microcapsules thereof. Generally, the concentration of the microencapsulated material will 30 range from about 480 to 700 g/1 of total composition, preferably 480 to 600 q/l.
Concentrates are usually solutions of active ingredient in water-immiscible or partially water-immiscible solvents together with a surface active agent. Suitable solvents for the active ingredient of '',, .

_44~ 5 this invention include dimethylformide, dimethylsulfo~ide, N-methylpyrrolidone, hydrocarbons and water-immiscible ethers, esters or ketones. However, other high strength liquid concentrates may be formulated by dissolving the active ingredient in a solvent then diluting, e.g., with kerosene, to spray concentration.
The concentrate compositions herein generally contain from about 0.1 to 95 parts (preferably 5-60 parts) active ingredient, about 0.25 to 50 parts (preferably 1-25 parts) surface active agent and where required about 4 to 94 parts solvent, all parts being by weight based on the total weight of emulsifiable oil.
Granules are physically stable particulate compositions comprising active ingredient adhering to or distributed through a basic matr~x of an inert, finely-divided particulate extender. In order to aid leaching of the active ingredient from the particulate, a surface active agent such as those listed hereinbefore can be present in the composition. Natural clays, pyrophyllites/ illite and vermiculite are examples of operable classes of particulate mineral extenders. The preferred extenders are the porous, absorptive, preformed particles such as preformed and screened particulate attapulgite or heat expanded, particulate vermiculite and the finely-divided clays such as ~aolin clays, hydrated attapulgite or bentonitic clays. These extenders are sprayed or blended with the active ingredient to form the herbicidal granules.
The granular compositions of this invention may contain from about 0.1 to about 30 parts preferably from about 3 to 20 parts by weight of active ingredient per 100 parts by weight of cla~ and 0 to about 5 parts by weight of surface active agent per 100 parts by weight of particulate clay.
The compositions of this invention can also contain other additaments, for example, fertilizers, other herbicides, other pesticides, safeners and the like used as adjuvants or in combination with any of the above-described adjuvants. Chemicals useful in combination with the active ingredients of this invention include, for example, triazines, ureas, carbamates, acetamides, acetanilides, uracils, acetic acid or phenol derivatives, thiolcarbamates, triazoles, benzoic acids, nitriles, biphenyl ethers and the like such as:
Heteroc clic Nitro en/Sulfur Derivatives Y g 2-Chloro-4-ethylamino-6-isopropylamino-s-triazine 2-Chloro-4,6-bis(isopropylamino)-s-triazine 2-Chloro-4,6-bis(ethylamino)-s-triazine 3-Isopropyl-lH-2,1,3-benzothiadiazin-4-(3H)-one 2,2 dioxide 3-Amino-1,2,4-triazole 6,7-Dihydrodipyrido(1,2-a:2'rl'-c)-pyrazidiinium salt 5-Bromo-3-isopropyl-6-methyluracil 1,1'-~imethyl-4,4'-bipyridinium Ureas N'-(4-chlorophenoxy) phenyl-N,N-dimethylurea N,N-dimethyl-N'-(3-chloro-4-methylphenyl) urea 3-(3,4-dichlorophenyl)-1,1-dimethylurea 1~3-Dimethyl-3-(2-benzothiazolyl) urea 3-(p-Chlorophenyl)-l,l-dimethylurea l-Butyl-3-(3,4-dichlorophenyl)-1-methylurea ~Z~16S

Carbamates/Thiolcarbamates 2-Chloroallyl diethyldikhiocarbamate S-(-4-chlorobenzyl)N,N-diethylthiolcarbamate Isopropyl N-t3-chlorophenyl) carbamate S-2,3-dichloroallyl N,N-diisopropylthio~carbamate Ethyl N,N-dipropylthiolcarbamate S-propyl dipropylthiolcarbamate Acetamides/Acetanilides/Anil-nes/Amides 2-Chloro-N,N-diallylacetamide N,N-dimethyl-2,2-diphenylacetamide N (2,4-dimethyl-5- [[(trifluoromethyl)sulfonyl]
amino]phenyl)acetamide N-Isopropyl 2-chloroacetan~lide 2'~6'-Diethyl-N-methoxymethyl-2-chloroacetanilide 2'-Methyl-~' ethyl-N-(2-methoxyprop-2-yl)-2-chloroacetanilidea,~,a -Trifluoro-2,6-dinitro-N,N-dipropyl-~-toluidine N-(l,l--dimethylpropynyl)-3,5-dichlorobenzamide Acids/Esters/Alcohols 2,2-Dichloropropionic acid 2-Methyl 4-chlorophenoxyacetic acid 2,4-Dichlorophenoxyacetic acid Methyl-2-e4-(2,4-dichlorophenoxy)phenoxy]
propionat~
3-Amino-2,5-dichlorobenzoic acid 2-Methoxy-3,6-dichlorobenzoic acid 2s3,6-T.richlorophenylacetic acid Sodium 5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoate .~

~2~3~

~,6-~initro-o-sec-bu~yipnenol N-(phosphonomethyl) g1~cine and its C
monoalkyl amil~ and alk1ine m~ta1 sa~.~ and combinations thereof :5 Ethers 2,4-Dichlorophenyl-4-nitrophenyl ether 2-Chloro~ , a -trif1uoro-p-tolyl-~-ethoxy- .
4-nitrodiphenyl ether Miscellaneous 2,6-Dichlorobenzonitrile Monosodium a~id methanearsonate Disodium me~hanearsonate Fertilizers useful in combination with tAe active ingredients include, for example, ammonium nitrate, urea, potash ana superphosphale. Other useful aaditaments include materials in which plant org~nisms take root and grow such as compost, manure, humus, s~nd and the like~
Herbicio~l formulations of the types described above are exemplified in several illustrative em~od~ments below.

I. Emulsifl~le Concentrates _ EC's~

Wei~ht Percent A. Compound of Example No. l 35O6 C~lcium dodecylbenzene 5ul-fonate/polyoxyethylene ethers blend (e.g., Atlox~ 3437F) 5.0 Mono~hlorobenzene 29.7 C~ aromatic hyarocar~on 29.7 10(~. 0 ,~

-48- 12~6~65 AG~

B. Compound of Example ho. 3 ~5.U
Calcium dodecyl sulfonate/al-kylaryl polyether alcohol blend ~.U
Cg aromatic hydrocarbons solvent li.0 1~0.

C. Compound of Example No. 4 5.0 Calcium dodecylbenzene sulfonate~
polyoxyethylene ethers blend (e.g., Atlox 3437F) 1.0 Xylene 94.0 10~. ()O

II. _i~uid Concentrates Weight Percent A~ Compound of Example No. 5 10.0 Xylene gO.0 100.00 B. Compound of Example No. 6 ~5.0 Dimethy1 suifoxi~e 15.0

11~O . O() ~:20~ C. Compound of Example No. 18 50.0 N-methylpyrrolidone 50.0 130.

D. Compound of Example No~ 19 5.0 : Ethoxylated castor oii 2000 Rhodamine B .5 Dimetnyl formami~e 74.5 , ~ : i00.00 -49- 3~Z~S ~G~

IIl. Er.lulsions ~eignt Per~ent A. Compound of Exdmple No. 7~0.0 Polyoxyethylene/polyoxy-propylene block copolymer with butanol (e.g., Tergitol~ XH) ~.0 Water 56.0 100. 00 B. Compound of Example No~ 8 5.0 Polyoxyethylene~polyoxy~
propylene block copolymer with butanol 3~5 Water 91.5 100. OU

IV. Wettable Powders Weight pe~-cent A. Compound of Example No. 925.0 Soaium lignosulfonate 3~0 : Sodium N-methyl-N-oleyl-taurate 1.0 Amorphous siiica (synthetic) 71.0 lOOoO0 B. Compound of Example No. 10 80.0 Sodium dloctyl sulfosuccinate 1.25 :~ Calcium lignosulfonate 2.75 ~norphous si~ica (synthetic) 1~.0~
~25 100.00 C. Compound of Example No. 11 10.0 Soàiulll lignosul~onate 3.0 Sodium ~-methyl-N-oleyl-taurate l.0 : Kaolinit~ clay 86.0 100.~0 ~50~ ~ 2~.

V. Dusts weiyh~ Per~ent A. Compound of Example No. 12 2.0 Attapulg ite 9~3 . 0 iO0. 00 B. Compound of Example No. 1360.0 Montmorillonite 40.0 100. 00 C. Compound of Example No. l~30.G
lQ ~entonite 70.0 lQ0.0 D. Compound of Example No. 15 l.0 Diatomaceous earth 99.0 100. 00 }5 VI. Granules Weiyht Per~ent ~ ~ A. Compound of Example No. 1615~0 : Granular attapulgi~e (20/40 mesh) 85.0 100. 00 B. ompound of Example No. 17 30.0 Diatomaceous earth (20/40) 70.0 1 0 0 . O () C. Compound o Example NoO 18 0.5 Bentoni~ (20/40) 99.S
10~.00 D. Compound ol ExampLe No. 1~5.0 ~: : Pyrophylllte ~;20/40) ~5.() lOU. OC

' ~Z(36~i5 A~ J

VLI. ~1crocapsuies A. Compound of Example No. 1 encapsulated in polyurea snell wall 4~.
Sodium lignosulfonate (e.g.
~~eax ~a~ ) Water ~9 9 lUOo OO

B. Compound of Example No. 3 encapsulated in polyurea shell wall 10.0 10Potassium lignosulfonate (e.g., Re~as C-21~ ) .5 Wa~er 89.5 10~. 0 C. Compound of Example No. 4 en-15capsu~ated in polyurea shell wail ~0.0 : Magnesium salt of lignosulfate (Treax ~ ~ 2.0 : Water 1~.0 1()0. 0~

20 ~ When operating in accordance with the present : invention, effective amounts of the acetaniiides of this invention are applied to the soiL containing the : : plants, or are incorporated into aquatic rlledia in any : convenient fashion. The application of liquid and particulate solid compositions to the soil can be carried out by conventional methods, e.g., power d~s~ers, boom and hand sprâyers and spray dusters. The compositions can also be applied f~om airplanes as a dust o a spray because of t}~eir e~fectiveness at ïow 30: ~osages. The application of herbicidal compositions : ~ to aquatic pl~nts is usually carried out by a~ding t~le co~positions to the aquatic media in the area where ~ control of t~e a~uatic plants is desired.
: ~, - 5 2 - ~2~6~5 Tne application of an efEective amoun~ of the compounds of this invention to the locus of unàesired weed~ is essential and cri~ical ~or the practice o~ th~
present invention. The exact amount o~ active ingredient to be employe~ is dependent upon various factors, including the plant species and stage of developn~ent thereof, the type and condition of 50il, the amount of rainfall and the specific acetanilide employed. In selectlve preemergence application to the plants or to the soil a dosage of rom 0.~2 to about 11.2 ~g/ha, preferably from about 0.04 to about 5.6 kg/ha, or suitably from 1.1~ to 5.6 kg/ha of acetaniLide is usually employed. Lower or higher rates may be required in some instarlces. One skilled in the arf can readiiy determi~ne from this specification, including the above example, the optimum rate to be applied in any particuiar case.
The term l'soil" is employed in its broadest sense to be inclusive o~ all conventional "soils" as defined in Webster's New International Dictionary, Second Edition, Unabrldged (1961). 'rhus the term refers to any substance or media in which vegetation may take root and grow, and includes not only ear~h but also compost, manure, muckj humus, sand and the like, adapted to support plant growth.
Although the inv~ntion is described with respect to speci~ic modifications, the details t~lereof are not to be construed as limitations except to the extent _ndi-a~ea in ~le foilovlrg clairs.

:

Claims (25)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. Compounds having the formula wherein R is methyl or ethyl;
R1 is a C1-6 alkyl radical;
R2 is methyl, ethyl or t-butyl and R3 is hydrogen or methyl in a meta position;
provided that;
when R is ethyl, R1 is n-butyl, R2 is methyl and R3 is hydrogen;
when R3 is methyl, R and R2 are also methyl and R1 is isopropyl or n-butyl;
when R3 is hydrogen and R and R2 are both methyl, R1 is ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, n-pentyl, isopentyl, 2-methylbutyl, 1-methylpentyl, 2-methylpentyl or 1,3-dimethylbutyl;
when R2 is ethyl, R is methyl and R1 is isopro-pyl and when R2 is t-butyl, R and R1 are both methyl.

2. Compounds according to Claim 1 wherein R1 is a C3-5 alkyl radical and R and R2 are methyl radicals.

3. Compound according to Claim 2 which is N-methyl-2'-isopentyloxy-6'-methyl-2-chloroacetanilide.

4. Compound according to Claim 2 which is N-methyl-2'-n-propoxy-6'-methyl-2-chloroacetanilide.

5. Compound according to Claim 2 which is N-methyl-2'-n-butoxy-6'-methyl-2-chloroacetanilide.

6. Compound according to Claim 2 which is N-methyl-2'-sec-butoxy-6'-methyl-2-chloroacetanilide.

7. Compound according to Claim 2 which is N-methyl-2'-isopropoxy-6'-methyl-2-chloroacetanilide.

8. Compound according to Claim 2 which is N-methyl-2'-isobutoxy-6'-methyl-2-chloroacetanilide.

9. Compound according to Claim 1 which is N-ethyl -2'-n-butoxy-6'-methyl-2-chloroacetaniliae.

10. Compound according to Claim 1 which is N-methyl-2'-isopropoxy-6'-ethyl-2-chloroacetanilide.

11. Method for controlling undesirable plants in crop plants which comprises applying to the locus thereof a herbicidally effective amount of a compound having the formula wherein R is methyl or ethyl;
R1 is a C1-6 alkyl radical;
R2 is methyl t ethyl or t-butyl and R3 is hydrogen or methyl in a meta position;
provided that:
when R is ethyl, R1 is n-butyl, R2 is methyl and R3 is hydrogen;
when R3 is methyl, R and R2 are also methyl and R1 is isopropyl or n-butyl;

when R3 is hydrogen and R and R2 are both methyl, R1 is ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, n-pentyl, isopentyl, 2-methylbutyl, 1-methylpentyl, 2-methylpentyl or 1,3-dimethylbutyl;
when R2 is ethyl, R is methyl and R1 is isopropyl and when R2 is t-butyl, R and R1 are both methyl.

12. Method according to Claim 11 wherein in said compound R1 is a C3-5 alkyl radical and R and R2 are methyl radicals.

13. Method according to Claim 12 wherein said compound is N-methyl-2'-isopentyloxy-6'-methyl-2-chloroacetanilide.

14. Method according to Claim 12 wherein said compound is N-methyl-2'-n-propoxy-6'-methyl-2-chloroacetanilide.

15. Method according to Claim 12 wherein said compound is N-methyl-2'-n-butoxy-6'-methyl-2-chloroacetanilide.

16. Method according to Claim 12 wherein said compound is N-methyl-2'-sec-butoxy-6'-methyl-2-chloroacetanilide.

17. Method according to Claim 12 wherein said compound is N-methyl-2'-isopropoxy-6'-methyl-2-chloroacetanilide.

18. Method according to Claim 12 wherein said compound is N-methyl-2'- isobutoxy-6'-methyl-2-chloroacetanilide.

19. Method according to Claim 11 wherein said compound is N-ethyl-2'-n-butoxy-6'-methyl-2-chloroacetanilide.

20. Method according to Claim 11 wherein said compound is N-methyl-2'-isopropoxy-6'-ethyl-2-chloroacetanilide.

21. Method according to Claim 11 wherein said crops are leguminous crops.

22. Method for controlling undesirable plants in soybeans, peanuts, rape, cotton, snap beans, alfalfa and vegetable crops which comprises applying to the locus thereof a herbicidally effective amount of N-methyl-2'-isopentyloxy-6'-methyl-2-chloroacetanilide.

23, Method for controlling undesirable plants in soybeans, peanuts, rape, cotton, snap beans, alfalfa and vegetable crops which comprises applying to the locus thereof a herbicidally effective amount of N-methyl-2'-n-propoxy-6'-methyl-2-chloroacetanilide.

24. Method for controlling undesirable plants in soybeans, peanuts, rape, cotton, snap beans, alfalfa and vegetable crops which comprises applying to the locus thereof a herbicidally effective amount of N-methyl-2'-n-butoxy-6'-methyl-2-chloroacetanilide.

25. Method for controlling undesirable plans in soybeans, peanuts, rape, cotton, snap beans, alfalfa and vegetable crops which comprises applying to the locus thereof a herbicidally effective amount of N-methyl-2'-isobutoxy-6'-methyl-2-chloroacetanilide.