GB2072175A - Herbicidal 2-Haloacetanilides - Google Patents

Abstract

N-hydrocarbyloxymethyl-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 and bush beans. The herbicides herein are particularly effective against hard-to-kill perennial weeds such as quackgrass and yellow nutsedge and against annual weeds, including prickly sida, hemp sesbania, seedling Johnsongrass, shattercane, etc.

Description

SPECIFICATION Herbicidal 2-haloacetanilides Background of the Invention Field of the Invention This 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 having an alkoxymethyl radical on the anilide nitrogen, an alkoxy radical in one ortho position and a specific alkyl radical in the other ortho position, the closest prior art known to the inventor are U.S. Patent Numbers 3,442,945 and 3,547,620. The most relevant disclosures in the '945 and '620 patents are the compounds 2'-tertbutyl-2-chloro-N-methoxymethyl-6'-methoxyacetanilide and its bromo analog (Examples 18 and 34 of the '620 patent and Examples 1 8 and 36 of the '945 patent, respectively).

U. S. Patents 4,070,389 and 4,152,137 disclose a generic formula which encompasses compounds of the type disclosed in said '945 and '620 patents. However, the only disclosed species compound having an alkyl radical in one ortho position and an alkoxy radical in the other ortho position has an alkoxyethyl radical on the anilide nitrogen atom; compounds of this type are discussed in more detail below.

Other less-relevant prior art are Belgian Pat. No. 810,763 and German Application No.

2,402,983; the compounds of these references include compounds of the type disclosed in said '389 and '137 patents and are characterized by an alkoxyalkyl radical having two or more carbon atoms between the anilide nitrogen atom and the oxygen atom of the alkoxy moiety. The most relevant specific disclosures in said Belgian '763 patent and German '983 application appear to be compounds having an ethoxyethyl radical on the anilide nitrogen atom, a methoxy or ethoxy radical in one ortho position and a methyl or ethyl radical in the other ortho position; referring to the '763 patent, see Compound Numbers 7, 1 3 and 18; other less-relevant homologs of these compounds are also disclosed, e.g., Compounds 6, 9, 16 and 17, which have methoxyethyl or methoxypropyl radicals substituted on the nitrogen atom and a methoxy or ethoxy radical in one ortho position and a methyl radical in the other ortho position.

The above '945 patent contains some herbicidal data relative to those above-mentioned compounds having a chemical configuration most closely related to the invention compounds, and some data are presented in the other patents for other homologous and analogous compounds lessclosely related in chemical structure, e.g., said Compounds Numbers 6 and 9 in said '763 patent.More particular!y, 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 perennial weeds, quackgrass and yellow nutsedge and a broad spectrum of annual weeds including such hard-to-kill annual broadleaf weeds as prickly sida, hemp sesbania, jimson weed, etc. and annual grass weeds such as seedling johnsongrass, shattercane, alexandergrass (brachiaria), panicums (Texas, Fall and wild proso millet), red rice and itchgrass (Raoulgrass), while also controlling other noxious perennial and annual weeds, e.g., smartweed, lamsquarter, pigweed, foxtails, large crabgrass and barnyardgrass.

A highly useful and desirable 1property of herbicides is the ability to maintain weed control over an extended 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 disadvantage 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 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 organic matter or vice-versa. It is, therefore, advantageous that a herbicide be useful in all types of 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., by preemergence surface application or by 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 by soil incorporation.

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 object 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 heretofore unachieved in a single group of herbicides.

It is an object of this invention to provide herbicides which control hard-to-kill perennial and annual weeds such as quackgrass, yellow nutsedge, seedling johnsongrass, prickly sida, hemp sesbania, shattercane, alexandergrass, panicums, red rice, and itchgrass, as well as, and in addition to, a broad spectrum of other noxious weeds, e.g., smartweed, lambsquarters, pigweed, jimsonweed, foxtails, barnyardgrass and crabgrass, and also provide increased suppression of resistant weeds such as ragweed, velvetleaf, morningglory and cocklebur, while maintaining crop safety in a plurality of crops including soybeans, cotton, peanuts, rape and/or bush beans.

It is a further object of this invention to provide herbicidal effectiveness in the soil for periods ranging up to 18 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.

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 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.

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 particular crops.

It has now been found that a selective group of 2-haloacetanilides characterized by specific hydrocarbyloxymethyl radicals on the anilide nitrogen atom, specific alkoxy radicals in one ortho position and hydrogen or a methyl or ethyl radical in the other ortho position possess unexpectedly superior and outstanding herbicidal properties vis-a-vis prior art herbicides, including homologous 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 one or more of a plurality of crops including, particularly, soybeans, cotton, peanuts, rape and snap beans, and others as weil.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 perennial and annual weeds, such as the perennials quackgrass and yellow nutsedge, annual broadleafs such as prickly sida, hemp sesbania, jimsonweed, smartweed, lamsquarters, pigweed and annual grasses such as shattercane, alexandergrass, seedling johnsongrass, Texas panicum, wild proso millet, red rice, itchgrass, and other noxious weeds such as fall panicum, foxtails, barnyardgrass and crabgrass. Improved weed stand reduction has also been achieved in resistant weeds such as ragweed, velvetleaf, morningglory and cocklebur.

The compounds of this invention are characterized by the formula

wherein R is ethyl, n-propyl, isopropyl, isobutyl, sec-butyl, cyclopropylmethyl, allyl or propargyl; R, is methyl, ethyl n-propyl or isopropyl and R2 is hydrogen, methyl or ethyl; provided that; when R2 is hydrogen, R, is ethyl and R is allyl; when R2 is ethyl, R, is methyl and R is isopropyl; when R1 is methyl, R is ethyl, isopropyl, isobutyl, sec-butyl or cyclopropylmethyl; when R1 is ethyl, R is sec-butyl, allyl or propargyl; when R1 is n-propyl, R is ethyl and when R, is isopropyl, R is ethyl or n-propyl.

The preferred species of compound of this invention is 2'-methoxy-6t-methyl-N- (isopropoxymethyl)-2-chloroacetanilide.

Additional species of this invention are as follows: 2'-m ethoxy-6'-methyl-N-(ethoxymethyl)-2-chloroacetanilide, 2'-methoxy-6'-methyl-N-( 1 -sec-butoxy-methyl)-2-ch loroacetanilide, 2'-ethoxy-6'-methyl-N-(allyloxymethyl)-2-chloroacetanilide, 2'-ethoxy-6'-methyl-N-(propargyloxymethyl)-2-chloroacetanilide, 2'-ethoxy-N-(a llyloxymethyl)-2-chloro-acetanilide, 2'-methoxy-6'-ethyl-N-(isopropoxy-methyl)-2-chloroacetanilide, 2'-ethoxy-6'-methyl-N-( 1 -methylpropoxy-methyl)-2-chloroacetanilide, 2'-n-propoxy-6'-methyl-N-(ethoxymethyl)-2-chloroacetanilide, 2'-isopropoxy-6'-methyl-N-(ethoxymethyi)-2-chloroacetanilide and 2'-isopropoxy-6'-methyl-N-(n-propoxymethyl)-2-chloroacetanilide.

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 the azomethine route described in the above-mentioned U.S. Patent Numbers, 3,442,945 and 3,547,620. According to the azomethine process, the appropriate primary aniline is reacted with formaldehyde to obtain the corresponding methyleneaniline (substituted phenylazomethine), which is then reacted with a haloacetylating agent such as chloroacetyl chloride or chloroacetyl anhydride which, in turn, is reacted with the appropriate alcohol to obtain the corresponding N-alkoxymethyl-2-chloroacetanilide as the final product.

Another procedure described in more detail below involves the transetherification of the appropriate N-methylene ether-2-haloacetanilide with the desired alcohol to obtain the corresponding transetherified N-hyd rocarbyl methyl-2-haloacetanilide.

Still another process for producing compounds according to this invention involves an Nalkylation of the anion of the appropriate secondary 2-haloacetanilide with an alkylating agent under basic conditions. The N-alkylation process is described in more detail in Examples 11-14 herein.

Example 1 This example described the preparation of one preferred species, 2'-methoxy-6'-methyl-N (isopropoxymethyl)-2-chloroacetan ilide.

2'-methoxy-6'-methyl-N-(methoxymethyl)-2-chloroacetanilide (0.025 mole) in 100--150 ml of isopropanol containing about 0.02 mol of methane sulphonic acid was refluxed under a Soxhlet extraction apparatus the thimble of which contained activated 3A Molecular Sieves (25 g) to absorb the liberated methanol. The course of the reaction was followed by glc. When reaction was complete, the excess alcohol was removed in vacuo and the residue taken up in ether or chloroform. The solution was washed with 5% sodium carbonate solution, dried (Mg2SO4) and evaporated. The product was purified by Kugelrohr distillation. Yield, 55%; pale amber solid, m.p. 40-41 OC.

Anal: Calc'd for C,4H20CINO3(%): C, 58.84; H, 7.05; N, 4.90; CI, 12.41.

Found: C, 58.55; H, 7.08; N, 4.89; CI, 12.45 The product was identified as described in the lead sentence of this example.

Examples 2-9 Following substantially the same procedures, quantities of reactants and general conditions described in Example 1, but substituting the appropriate alcohols to effect the transetherification to obtain the end product, other N-hydrocarbyloxymethyl-2-haloacetanilides according to the above formula were prepared; these compounds are identified in Table I.

Table I Example Empirical B.P. OC Analysis No. Compound Formula (mm Hg) Element Calculated Found 2 2'-methoxy-6'-methyl-N- C,3H18CIN03 170 C 57.46 57.19 (ethoxymethyl)-2- (0.1) H 6.67 6.70 chloroacetanilide N 5.16 5.11 CI 13.05 13.09 3 2'-methoxy-6'-methyl- C,5H22ClNo3 C 60.10 59.90 N-(1 -methylpropoxy- H 7.40 7.36 methyl)-2-chloroacet- N 4.67 4.62 anilide Cl 11.83 11.97 4 2'-ethoxy-6'-methyl- C10H20ClNO3 110 C 60.50 60.30 N-(allyloxymethyl)- (0.07) H 6.77 6.80 2-chloroacetanilide N 4.70 4.64 Cl 11.91 11.69 5 2'-ethoxy-6'-methyl- C,5H,8CiNo3 140 C 60.91 60.98 N-(propargyloxymethyl)- (0.1) H 6.13 6.14 2-chloroacetanilide N 4.74 4.74 Cl 11.99 11.94 6 2'-ethoxy-6-methyl- C,6H24CINo3 135 C 61.24 60.98 N-(1-methylpropoxy- (0.09) H 7.71 7.69 methyl)-2-chloroacet- N 4.46 4.42 anilide Cl 11.30 11.22 7 2'-methoxy-6'-methyl- Cr5H22CINO3 140 C 60.10 59.88 N-(isobutoxymethyl)-2- (0.1) H 7.40 7.41 chloroacetanilide N 4.67 4.62 Cl 11.83 11.82 8 2'-methoxy-6'-methyl-N- C,5H20CIN03 145 C 60.50 60.26 (cyclopropylmethoxy- (0.1) H 6.77 6.77 methyl)-2-chloroacet- N 4.70 4.66 anilide Cl 11.91 11.80 9 2'-methoxy-6'-ethyl-N- C,5H22CiNo3 oil C 60.10 59.81 (isopropoxymethyl)-2- H 7.40 7.46 chloroacetanilide N 4.67 4.61 Cl 11.83 11.71 Example 10 This example describes the preparation of the N-(methoxymethyl) tertiary anilide starting materials used to prepare the final products in Examples 1-9.

The N-methylene ether substituted 2-chloro-acetanilide starting materials used in Examples 19 were prepared by alkylating the appropriate secondary 2-haloacetanilide by the N-alkylation process referred to above. That process will be illustrated in this example with respect to the preparation of the starting material in Example 1.

2'-methoxy-6'-methyl-2-chloroacetanilide (0.025 mol), bromomethyl methyl ether (0.05 mol) and benzyltriethylammonium bromide (2 g) were dissolved in methylene chloride (70 ml). Sodium hydroxide solution (40 ml of 50%) was then added portionwise with stirring and cooling keeping the temperature between 20 and 250C. When addition was complete, the mixture was stirred for an additional 1.5 hours. Water (100 ml) was then added with cooling and the layers separated. The methylene chloride layer was washed twice with 30 ml saturated sodium chloride solution, dried (Mg2SO4) and evaporated. The residual product was crystallized or distilled in vacuo to obtain a yellow liquid, bp 1400C at 1.2 mm Hg.

Anal. Caic'd for C,2H,8CIN03 (%): C, 55.92; H, 6.26; N, 5.44; Found: C, 56.15; H, 6.33; N, 5.36 The product was identified as 2'-methoxy-6'-methyl-N-(methoxymethyl)-2-chloroacetanilide.

Similarly, the starting N-methylene ether substituted 2-chloroacetanilides of Examples 2-9 were prepared by alkylation of the corresponding secondary anilide with bromomethyl methyl ether, respectively; the analogous chloromethyl and iodomethyl methyl ethers can also be used.

The secondary anilide starting material used in this example to prepare the tertiary Nmethoxymethyl compound was prepared by the chloroacetylation of the corresponding primary amine as follows: 2-methoxy-6-methylaniline (0.03 mol) in methylene chloride (30 ml) was stirred vigorously with a 10% sodium hydroxide solution (0.05 mol) while a solution of chloroacetyl chloride (0.033 mol) in methylene chloride (20 ml) was added keeping the temperature between 1 5-250C with external cooling. The reaction mixture was stirred for a further 30 minutes after the addition was complete, the layers separated and the methylene chloride layer washed with water, dried and evaporated in vacuo.

The product was crystallized from a suitable solvent to obtain white needles, mp 130-131 CC.

Anal. Calc d for C,OHX2CINO2 (%): C, 56.21; H, 5.66; N, 6.56; CI, 16.59 Found: C, 56.16; H, 5.66 N, 6.57; CI, 16.55.

The product was identified as 2'-methoxy-6'-methyl-2-chloroacetanilide.

The secondary anilides used as starting materials in Examples 2-9 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 substituted nitrobenzene in ethanol using platinum oxide catalyst.

As mentioned above, the products of this invention may also be prepared directly from the secondary anilide by use of said N-alkylation process, without first preparing the Nhydrocarbyloxymethyl intermediate (as described in Example 10), which is then transetherified to the final product as described in Example 1. Examples 11-14 illustrate the preparation of species of this invention by said N-alkylation process.

Example 11 2'-n-propoxy-6'-methyl-2-chloroacetanilide (4.35 g), chloromethyl ethyl ether, 3.4 g, benzyltriethyl-ammonium chloride, (1.5 g) were mixed in 250 ml of methylene chloride and chilled. To the mixture was added 50 ml of 50% NaOH at 1 50C and stirred for 2 hours, then 100 ml of water was added. The layers were separated, washed with water, then dried over MgSO4 and evaporated. The product was purified by Kugelrohr distillation to obtain 4.8 g (89% yield) of clear liquid, bp. 1 300C at 0.07 mm Hg.

Anal. Calc'd for C,5H22CINO3 (%): C, 60.10; H, 7.40; CI, 11.83 Found: C, 59.95; H, 7.39; CI, 11.79 The product was identified as 2'-n-propoxy-6'-methyl-N-(ethoxymethyl)-2-chloroacetanilide.

Example 12 2'-isopropoxy-6'-methyl-2-chloroacetanilide, 5.55 g, chloromethyl ethyl ether, 4.4 g, benzyltriethylammonium chloride, 2.5 g in 250 ml of methylene chloride mixed and cooled to OOC. To the mixture was added 50 ml of 50% NaOH all at once, while maintaining the temperature below 1 50C. The mixture was stirred for 2 hours, cooled, then 100 ml water added. The layers were separated, washed with water, dried over MgSO4 and evaporated to obtain 4.7 g (69% yield) of the product, a yellow oil.

Anal. Calc'd for C15H22CINO3 (%): C, 60.10: H, 7.40; N, 4.67; Cl, 1 1.83; Found: C, 60.10; H, 7.40; N, 4.64; Cl, 11.73.

The product was identified as 2'-isopropoxy-6'-methyl-N-(ethoxymethyl)-2-chloroacetanilide.

Example 13 Following substantially the same procedure described in Examples 11 and 12, but using chloromethyl propyl ether as the alkylating agent, 5.0 g (88% yield) of a yellow oil was obtained.

Anal. CaIc'd for C16H24CINO3(%): C, 61.24; H, 7.71; N, 4.46; CI, 1 1.30.

Found: C, 61.18; H, 7.76; N, 4.43; Cl, 1 1.31.

The product was identified as 2'-isopropoxy-6-methyl-N-(n-propoxymethyl-2-chloroacetanilide.

Example 14 Following the same procedure described in Examples 1 11-1 3, but substituting the appropriate sec-anilide and halomethyl allyl ether, a yellow oil, b.p. 1 340C/0.08 mm Hg (Kugelrohr) was obtained.

Anal. Calc'd for C,4H8CINO3 (%): C, 59.26; H, 6.39; N, 6.94; CI, 12.49.

Found: C, 59.20; H, 6.41; N, 6.95; CI, 12.52.

The product was identified as 2'-ethoxy-N-(a Ilyloxym ethyl)-2-chloroacetanilide.

The herbicides of this invention have been found to possess unexpectedly superior properties as preemergence herbicides, most particularly in the selective control of hard-to-kill perennial and annual weeds, including such perennials as quackgrass and yellow nutsedge; annual broadleaf weeds such as prickly sida, hemp sesbania, jimsonweed, smartweed, lambsquarters, pigweed and annual grasses such as seedling johnsongrass, shattercane, alexandergrass (Brachiaria plantaginea), Texas panicum, red rice, wild proso millet, itchgrass, foxtails (e.g., green and giant), barnyardgrass and large crabgrass.

Improved weed stand reduction relative to prior art acetanilides has also been achieved on other resistant species such as ragweed, velvetleaf, morningglory and cocklebur.

Selective control and increased suppression of the above-mentioned weeds with the invention herbicides has been found in a variety of crops including soybeans, cotton, peanuts, rape and snap beans (bush beans). Selectivity has been shown in some tests in sugarbeets, field corn, sweet corn wheat, barley and sorghum; however, these crops are usually less tolerant to the invention herbicides than are the foregoing crops. It will be understood by those skilled in the art that not all of the abovenamed weeds are selectively controlled by all the invention compounds under all conditions of climate, soil type, moisture and/or herbicide application modes.

In order to illustrate the unexpectedly superior properties of the compounds of this invention both on an absolute basis and on a relative b3sis, comparative tests were conducted in the greenhouse and in the field with: (1) compounds of the prior art most closely related in chemical structure to the invention compounds, (2) other homologs within the scope of said prior art which have superior herbicidal properties, and (3) commercial herbicidal compounds of chemical structure generally related to that of the invention compounds. All of the compounds in the comparative tests below are generically defined as substituted phenyl-N-alkoxyalkyl-2-haloacetanilides.As used in the tables of data herein the compared prior art compounds are identified as follows: A. 2'-methoxy-6'-tert-butyl-N-(methoxymethyl-2-chloroacetanilide; (Example 18, U.S. Patents 3,442,945 and 3,547,620).

B. 2'-methoxy-6'-tert-butyl-N-(methoxymethyl)-2-bromoacetanilide; (Example 34 of said '620 patent and Example 36 of said '945 patent).

C. 2',6'-diethyl-N-(methoxymethyl)-2-chloroacetanilide; (Example 5 of said '620 and '945 patents; this compound has the common name "alachlor" and is the active ingredient in the commercial herbicide Lasso, a registered trademark of Monsanto Company).

D. 2'-methyl-6'-ethyl-N-(ethoxymethyl)-2-chloroacetanalide; (Example 53 in said '620 patent; common name acetochlor").

E. 2,6'-dimethyl-N-(isopropoxymethyl)-2-chloroacetanilide; (Example 31 of said '620 patent and Example 33 of said '945 patent).

F. 2'-methoxy-6'-methyl-N-(methoxyethyl)-2-chloroacetanilide; (Compound No. 6 in said Belgian '763 patent).

G. 2'-methoxy-6'-methyl-N-(ethoxyethyl)-2-chloroacetanilide; (Compound No. 7 in Belgian Patent No. 810,763).

H. 2'-methoxy-6'-methyl-N-(1-methoxyprop-2-yl)-2-chloroacetanilide; (Compound No. 9 in said Belgian '763 patent) and 1. 2'-methyl-6'-ethyl-N-( 1 -methoxyprop-2-yl)-2-chloroacetanilide: (U.S. Patent No. 3,937,730; common name "metolachlor"; this compound is the active ingredient in commercial herbicide "Dual", a registered trademark of Ciba-Geigy Corporation).

In preemergence herbicidal tests, compounds of this invention were compared with compounds A--l of the prior art with respect to control of various perennial and annual weeds, with emphasis on the hard-to-kill species which are prevalent infestations on such important crops as soybeans, cotton, peanuts, rape and bush beans. Test results are presented below.

In the discussion of data below, reference is made to herbicide application rates symbolized as "GR15" and "GR85", these rates are given in pounds per acre (Ibs/A), which are convertible into kilograms per hectare (kg/ha) by multiplying the Ib/A rate by 1.12. GR15 defines the maximum rate of herbicide required to achieve 15% or less crop injury, and GR85 defines the minimum rate required to achieve 85% inhibition of weeds. The GR,5 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 factor" ("SF") for a herbicide in given crops and weeds. The selectivity factor is a measure of the degree of crop safety and is expressed in terms of the GR1WGR85 ratio, i.e., the GR15 rate for the crop divided by the GR85 rate for the weed, both rates in Ib/A.In the tables below, where used, selectivity factors are shown in parenthesis following the weed; the symbol "NS" indicates "non-selective"; marginal or undetermined selectivity is indicated by a dash (-) after the weed and a blank space indicates that the plant species was not in a particular test, that the data was not obtained for some reason or was less significant than other data present, e.g., some shorter term observations are omitted in favor of longer term data or longer term data omitted because shorter term data was definitive of a particular herbicidal activity.

Since crop tolerance and weed control are inter-related, a brief discussion of this relationship in terms of selectivity factors is meaningful. In general, it is desirable that crop tolerance values be high, since higher concentrations of herbicide are frequently desired for one reason or another. Conversely, it is desirable that weed control rates be small, i.e., have high unit activity, for economical and possibly ecological reasons. However, 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 selectivity of the herbicide for weed control in a given crop.

The preemergence 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 the pre-seeded test containers. In the field 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"x2.75" (24.13 cmxi3.34 cox6.99 cm) or plastic pots 3.75"x3.75"x3" (9.53 cmx9.53 cmx7.62 cm) having drain holes in the bottom, are level-filled with Ray silt loam soil then compacted to a level 0.5 inch (1.27 cm) from the top of the pots. The pots are then seeded with a plant species to be tested, then covered with an 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 I/ha, 2.11 kg/cm2); other sprayer means, e.g., a DeVilbiss sprayer, are also used on occasion.Each pot receives 0.25 inch (0.64 cm) water as overhead irrigation and the pots are then placed on greenhouse benches for subsequent sub-irrigation as needed. As an alternative procedure, the overhead irrigation may be omitted. Observations of 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 the soil is placed a 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 pans. After treatment, the pans are given an initial overhead irrigation of water, equivalent to one-fourth 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 three weeks after seeding and treating.

In a first series of tests, preemergence herbicidal activity data is presented in Table II comparing the relative efficacy of invention compounds with relevant prior art compounds against yellow nutsedge and quackgrass in soybeans, cotton and corn.

Table II Rate for GR85 {Lb/A) Rate for GR15 (Lb/A) Compound Nutsedge Quackgrass Soybean Cotton Corn A > 2.0 2.8 (-) > 2.0 (-) O.15(NS) 1.4 0.25 (NS) 0.25 (NS) B 0.62 0.5 (NS) > 2.0 ( > 2.0) 0.03 (NS) 2.5 1.0 (NS) 0.06 (NS) C 0.4 1.5(4) 0.7 (2) 0.5 1.0(2) 0.75(1.5) D 0.2 0.35(1.5) 0.22(1) 0.20 (1) 0.16 0.35 (2) 0.20 (1) E 0.15 O.19 (1) 0.43 (3) 0.08 (NS) F 0.30 0.19(NS) 0.19 (NS) < 0.2 (NS) 0.24 0.19 (NS) < 0.2 (NS) Tablet (cont.) Rate for GR85 (Lb/A) Rate for GR15 KLb/A) Compound Nutsedge Quackgrass Soybean Cotton Corn G 0.22 < 0.06 (NS) 0.35 (1.5) < 0.06 (NS) 0.18 < 0.06 (NS) < 0.06 (NS) H 1.3 1.96(1.5) 2.6 (2) < 1.3 (NS) 0.32 1.92 (6) 2.4 (7.5) 1.12(3.5) I 1.5 < 1.5 (NS) < 1.5 (NS) < 1.5 (NS) 0.8 1.2(1.5) 1.2(1.5) < 0.8 (NS) Ex. 1 0.09 0.25 (3) 0.25 (3) < 0.06 (NS) 0.18 0.25 (1.5) < 0.06 (NS) Ex.2 0.15 0.15(1) 0.15(1) < 0.15(NS) 0.06 0.12 (2) 0.06(1) < 0.06 (NS) Ex. 3 0.23 0.69 (3) 0.69 (3) < 0.23 (NS) 0.12 0.72 (6) < 0.12 (NS) Ex. 4 0.30 0.9 (3.0) 0.9 (3.0) < 0.30 (NS) 0.20 0.9 (4.5) < 0.20 (NS) Ex.5 0.25 3.0(12.0) 2.5(10.0) < 0.25(NS) 0.25 3.0 (12.0) < 0.25 (NS) Ex. 6 0.23 1.8(8.0) 2.3 (10.0) < 0.23 (NS) 0.25 2.0 (8.0) < 0.25 (NS) Ex. 7 0.20 0.80(4.0) 1.3 (6.5) 0.13 (NS) 0.5 0.80 (1.6) 0.13 (NS) Ex.8 0.33 0.50 (1.5) 0.64 (1.9) < 0.12 (NS) 0.15 0.50(3.3) < .12(NS) Ex. 9 0.50 5.0 (10.0) 1.5 (3.0) < 0.25 (NS) 0.42 5.0(11.9) < 0.25 (NS) Ex. 12 0.11 0.25 (2.5) 0.22 (2.0) < 0.11 (NS) 0.10 0.25 (2.5) < 0.10(NS) Ex. 13 0.20 0.40 (2.0) 2.4 (12.0) < 0.20 (NS) 0.25 0.50 (2.0) < 0.25 (NS) Ex. 14 0.32 > 5.0( > 15.6) 1.25(3.9) 5.0(15.6) 0.45 > 5.0( > 11.1) 5.0(11.1) Reference to the data in Table II will show that, in general, the compounds of this invention as a class are significantly more active, i.e, have a higher unit of activity, against both yellow nutsedge and quackgrass and exhibit greater crop safety in soybeans and cotton than the reference compounds.

More particularly, with respect to yellow nutsedge control, it will be noted that every invention compound tested was outstandingly more active against yellow nutsedge than Compounds A and B, which are structurally the most closely related of the reference compounds, and Compound H, which while less closely related than A and B may be considered more closely related in certain aspects to the invention compounds than are Compounds, C, D, E and I. In still more particular, it will be noted that the compound of Example 1, having a GR85 of 0.09 lb/A, was approximately twice as active as the most active reference compound, Compound E (GR850 0.15), while having a crop safety factor three times as great as Compound E in soybeans and equivalent safety in cotton. It will also be noted that the invention compounds of Examples 2 and 12 also had equivalent and greater, respectively, unit activity than Compound E against yellow nutsedge. Moreover, although reference Compounds F and G have a fairly high unit activity, neither compound was selective against yellow nutsedge in soybeans, nor was Compound F selective in cotton. Although Compound G did selectively control nutsedge in cotton, the degree of safety was less than that for all invention compounds except Example 2 and markedly less than that for Examples 5, 6 and 13. The selectivity factors of the compounds of Examples 9 and 14 against nutsedge in soybeans were particularly outstanding.

With respect to quackgrass control, the compound of Example 2 was almost three times as active as the most active reference chemical, Compound D, while maintaining equivalent crop safety in soybeans. Invention compound of Example 3 also had greater unit activity against quackgrass and three times the soybean safety as Compound D. Again, it will be noted that every invention compound tested against quackgrass had outstandingly superior unit activity relative to Compounds A and B, the most-closely related reference compounds tested. Although the unit activity of Compound H against quackgrass was slightly higher than that for the compounds of Examples 9 and 14, the selectivity factors for the latter compounds against quackgrass in soybeans was about twice that of Compound H, the next closest related of the reference compounds.Moreover, reference Compounds A, B, F and G were non-selective against quackgrass in soybeans.

Further observations to note in the data of Table II are that of all compounds tested, the compounds of Example 5, 6, 9 and 14 had the outstandingly highest safety factors in soybeans relative to both yellow nutsedge and quackgrass. The compounds of Examples 5, 6 and 13 had by far the highest safety factors in cotton relative to yellow nutsedge. It is further to be noted that the outstanding crop safety factors of the compounds of Examples 5, 6, 9, 13 and 14 are accompanied by very low GR85 rates, indicating high unit activity against yellow nutsedge and quackgrass. In these tests, most of the invention compounds were non-selective in corn as were all but three of the reference compounds. However, the compound of Example 1 4 exhibited outstandingly superior selectivity relative to both quackgrass and yellow nutsedge in corn.

In other comparative tests, the preemergence herbicidal activities of reference Compounds C and D and the compound of Example 1 were tested against various annual broadleaf weeds at an application rate of 3.0 Ib/A (3.36 kg/ha). Observations were made 6-7 weeks after treatment (WAT) and the percent control of the weeds recorded; the data from these tests are shown in Table Ill.

Table Ill Annual Broadleaf Weed Control Preemergence 6-7 WAT Percent Con trol a t 3.0 tb/A Compound Weed Example 1 C D Prickly sida 93 35 73 Hemp sesbania 100 0 69 Pigweed 83 62 88 Smartweed 88 64 76 Lambsquarter 75 61 81 Ragweed 72 53 43 Jimsonweed 98 68 98 From the data in Table Ill, it is apparent that the compound of Example 1 exhibited outstandingly superior activity relative to Compound C against very annual broadleaf weed tested. Similarly, the compound of Example 1 exhibited markedly superior activity relative to Compound D against prickly sida, hemp sesbania, smartweed and ragweed, while exhibiting equivalent activity against jimsonweed, and slightly less unit activity against pigweed and lambsquarters.

In further comparative tests, field tests were conducted to determine the relative preemergence herbicidal activities and crop selectivities of the compound of Example 1 relative to reference Compounds C, D, E and I against barnyardgrass, prickly sida and hemp sesbania in soybeans. These tests were conducted in discrete plots of clay (Sharkey) soil containing 2.0% organic matter and treated with various concentrations of each herbicide applied as an emulsifiable concentrate at an application volume of 30 gal/A (280.5 kg/ha). Observations were made 4 weeks and 7 weeks after treatment.Based upon three replications, the test data show that at the 7 weeks observation, the only compound which selectively controlled hemp sesbania was the compound of Example 1; such control (GR85) was achieved with only 1.75 Ib/A (1.96 kg/ha), whereas the GR85 for each of Compounds C, E and I was 5.0 Ib/A (5.6 kg/ha) and 4.5 Ib/A (5.0 kg/ha) for Compound D. The GR15 in soybeans was 3.5 Ib/A (3.9 kg/ha) resulting in a 2.0 fold safety factor for the compound of Example 1. Thus, it required about 3 times as much of the reference compounds to achieve GR85 as required by the compound of Example 1, but without selectivity in soybeans.

Compounds C and D were non-selective against prickly sida in soybeans at 7 WAT. Compound I required 3.75 Ib/A (4.2 kg/ha) and Compound E required 2.5 Ib/A (2.8 kg/ha) to achieve GR85 and selectivity factors of 1.1 fold and 1.5 fold, respectively. In contrast, the compound of Example 1 achieved GR85 with only 0.75 Ib/A (0.8 kg/ha) and a selectivity factor of 4.7 fold in soybeans.

Compounds C, D and E were non-selective against barnyardgrass in soybeans at 7 WAT.

Compound I and the compound of Example 1 had substantially equivalent safety factors, i.e., 1.5 fold vs. 1.4 fold, respectively.

Thus, the above field tests show that, but for comparable control of barnyardgrass relative to Compound I, the compound of Example 1 was significantly superior to reference Compounds C, D, E and I in the selective control of all three annual weeds in soybeans at 7 weeks after treatment.

In further tests to determine relative herbicidal activities and selectivities for still longer periods of time, the same herbicides used in the preceding test were again tested in the field, this time in discrete plots of soil of silty clay to silty clay loam containing 3.0-3.5% organic matter. In parallel tests, emulsifiable concentrates of the respective herbicides were surface applied and pre-plant incorporated for preemergence control again at 30 gal/A containing the appropriate concentration of herbicide as active ingredient. In these tests, the herbicides were compared against the perennial weed quackgrass and the annual broadleaf weeds ragweed, pigweed and smartweed in soybeans.These tests were exposed to heavy rainfall measuring 1.75 in. (4.45 cm) on the fifth day after treatment ("DAT") and 0.9 in. (2.29 cm), 0.6 in. (1.52 cm), 0.5 in. (1.27 cm) and 0.5 in. of rain on succeeding days. The test data are shown in Table IV.

Table IV Preemergence Activity Pre-plant Incorporated GRa5 FLb/AJ GR,s (Lb/A) Compound WA T Quackgra-s Ragweed Pig weed Smartweed Soybeans Ex. 1 3 2.0 1.5 6 2.0 5.25 2.0 2.25 2.25 9.5 2.25 > 6.0 3.0 > 3.0 C 3 > 6.0 > 4.0 6 > 6.0 > 6.0 > 6.0 > 6.0 > 4.0 9.5 > 6.0 > 6.0 > 6.0 > 4.0 D 3 5.0 3.5 6 > 6.0 > 6.0 > 6.0 5.0 3.75 9.5 6.0 > 6.0 > 6.0 4.0 E 3 > 6.0 2.0 6 > 6.0 > 6.0 3.75 4.0 2.5 9.5 > 6.0 > 6.0 4.0 3.75 1 3 > 6.0 1.5 6 > 6.0 > 6.0 > 6.0 > 6.0 3.5 9.5 > 6.0 > 6.0 5.25 4.5 Surface-Applied Ex. 1 3 2.25 1.5 6 2.25 4.0 4.0 3.0 3.0 9.5 4.0 4.5 3.0 4.25 3.75 C 3 5.25 3.5 6 > 6.0 > 6.0 4.0 > 6.0 2.0 9.5 > 6.0 > 6.0 4.5 5.25 > 4.0 D 3 > 6.0 0.3 6 > 6.0 > 6.0 6.0 6.25 3.5 9.5 > 6.0 > 6.0 4.5 6.0 4.75 E 3 5.0 2.25 6 > 6.0 > 6.0 5.0 4.0 1.75 9.5 > 6.0 > 6.0 4.5 5.0 4.25 1 3 > 6.0 4.0 6 > 6.0 > 6.0 > 6.0 > 6.0 4.0 9.5 > 6.0 > 6.0 > 6.0 > 6.0 4.0 Referring to the data in Table IV, it will be noted that in the pre-plant incorporated tests none of the reference compounds selectively controlled any of the test weeds in soybeans at rates up to 6.0 Ib/A (6.7 kg/ha), the maximum test rate, at the 6 weeks and 9.5 weeks observations. As indicated hereinabove, selectivity is indicated by a selectivity factor, or GR1wGR85 ratio, of 1.0 or greater; the greater the value, the greater the selectivity.In contrast, the compound of Example 1 exhibited selective control of quackgrass, pigweed and smartweed at 6.0 weeks and control of quackgrass and smartweed at 9.5 weeks. The herbicidal activity of the compound of Example 1 is shown to be on the order of 3 or more times as great as the reference compounds against quackgrass and pigweed (except for Compound D) and approximately 2 or more times as active as the reference compounds (except Compound D at 6 and 9.5 weeks and Compound E at 9.5 weeks). None of the herbicides selectively controlled ragweed in this test, but the compound of Example 1 was more active against this weed than the reference compounds at 6 weeks.

In the test data based on surface application of the herbicides, again, none of the reference chemicals selectively controlled any of the weeds in the test in soybeans at rates of 6.0 Ib/A or less at the 6 weeks or 9.5 weeks observations, except for Compound D in pigweed at the 9.5 weeks observation. In these tests, selective weed control was observed for the compound of Example 1 in quackgrass and smartweed at 6 weeks and in pigweed at 9.5 weeks; the safety factor here was slightly greater than that for Compound D, i.e., 1.3 vs. 1.1 fold. Again, the compound of Example 1 exhibited much more herbicidal activity than the reference compounds in these tests.

From the data in Table IV, it is apparent that from the criteria of unit activity against weeds, soybean tolerance to the herbicides, safety factors and modes of herbicide application, the compound of Example 1 exhibited substantially superior properties as a preemergence herbicide than did the compared reference compounds.

The persistent weed control exhibited by the compound of Example 1 under the heavy rainfall conditions noted above demonstrated that the compound was not readily leached.

In further comparative field tests, the compounds of Example 1 and reference Compounds D and E were tested for selective control of prickly sida and crabgrass in cotton under both surface application and pre-plant incorporation modes of herbicide application; yellow nutsedge was included in the preplant incorporated tests. The soil in these tests was silt loam having 1.7% organic matter. Observations were taken at 2, 6 and 9 weeks after treatment. Based upon three replications, data from the surfaceapplied tests showed that the compound of Example 1 had over twice the unit activity against prickly sida as Compounds D and E at 6 weeks and 1.5 times their activities at 9 weeks. Compound D was non-selective against prickly sida in cotton at 6 and 9 weeks.The selectivity factors for Compound E at 6 and 9 weeks, respectively, were 1.1 and 1.2 compared with 3.3 and 1.8 for the compound of Example 1. Although the unit activities of each tested compound were comparable against crabgrass at 6 weeks, the compound of Example 1 was more active than Compound E.at 9 weeks and more selective (i.e., S.F. of > 4.0) than Compound D having an S.F. of 2.8.

In the pre-plant incorporated tests, after 9 weeks the unit activity of the compound of Example 1 was more than twice that of the reference chemicals against yellow nutsedge, slightly less than twice the unit activity of the reference chemicals against crabgrass and greater than one and one-third times the unit activity of the reference chemicals against prickly sida. In this field test, the compound of Example 1 selectively controlled yellow nutsedge in cotton up to 6 weeks after treatment, but the reference chemicals showed no selectivity even at the 2-weeks observation. Although none of the test chemicals selectively controlled prickly sida in this P.P.I. test, the margin of selectivity was much closer for the compound of Example 1 than for the other compounds.The compound of Example 1 and Compound E narrowly controlled crabgrass at 2 weeks, but were non-selective thereafter; Compound D was not selective against crabgrass at any of the observation dates.

Therefore, the salient conclusions derived from the above-mentioned field tests in cotton are that the compound of Example 1 was markedly more active than the reference compounds against the weeds yellow nutsedge and prickly sida, while maintaining that activity for a longer period of time, and that the compound of Example 1 had superior selectivity factors with respect to these weeds.

Moreover, the compound of Example 1 had superior unit activity relative to Compound E and superior selectivity relative to Compound D against crabgrass in cotton at 9 weeks.

Further comparative tests between the compound of Example 1 and Compounds D and E were conducted to determine their relative herbicidal activities and soil life against the perennial weeds yellow nutsedge and quackgrass. Compounds D and E are among the most active selective herbicides of the 2-haloacetanilides of the prior art and have been considered as standards for the class in tests for other herbicides against nutsedge and quackgrass and other weeds. In the tests discussed here, two replicates of each treatment were planted with 25 yellow nutsedge tubers and 25 quackgrass rhizome fragments.The herbicides were incorporated in the cover layer of soil at rates sufficient to determine the GR, rate, i.e., the minimum rate (Ib/A) required to achieve 50% control of the weeds; 10 Ib/A (11.2 kg/ha) was the maximum and 1.25 Ib/A (1.4kg/ha) the minimum rates actually applied.

Observations were made at 3, 6, 1 2 and 1 8 weeks. After each observation, the cover layer of soil was removed, the old tubers and rhizome fragments removed and replanted and placed in the greenhouse for the succeeding cycle. Test results are shown in Table V; "WAT" means "weeks after treatment".

Table V Soil Life GR50 Lb/A (Kg/Ha) Yellow Compound Nutsedge Quackgrass WA T Example < 1.25 ( < 1.4) < 1.25( < 1.4) 3 < 1.25 ( < 1.4) < 1.25 ( < 1.4) 6 1.25(1.4) 1.25 (1.4) 12 7.5 (8.4) 10.0(11.2) 18 D < 1.25 ( < 1.4) < 1.25( < 1.4) 3 1.0 (1.12) < 1.25 ( < 1.4) 6 5.25 (5.9) 5.0 (5.6) 12 > 10.00 ( > 11.2) > 10.0 ( > 11.2) 18 E < 1.25 ( < 1.4) < 1.25 ( < 1.4) 3 1.25(1.4) 1.5 (1.7) 6 7.0 (7.8) 10.0 (11.2) 12 > 10.0 ! > 11.2) > 10.0 ( > 11.2) 18 Reference to the data for yellow nutsedge control in Table V indicates that at 3 weeks after treatment the GR, rate of each compound was less than 1.25 Ib/A, with some definite differences appearing after 6 weeks. By 12 weeks major differences in the control of yellow nutsedge were manifest. Thus, where it required only 1.25 Ib/A of the compound of Example 1 to control 50% of the weed, it required 5.25 Ib/A of Compound D and 7.0 Ib/A of Compound E to achieve the same degree of control of yellow nutsedge. Also, at 18 WAT, it required only 7.5 Ib/A of the compound of Example 1 to control 50% of the nutsedge as against some indeterminate amount above 10 lb/A (the maximum rate used) of Compounds D and E.

Similarly, the quackgrass data in Table V show that at 6 WAT, the compound of Example 1 and Compound D had slightly superior activity relative to Compound E. However, at 12 WAT, the outstanding supremacy of the compound of Example 1 is shown in requiring only 1.25 Ib/A to achieve the same control of quackgrass as required by 5.0 Ib/A of Compound D and 10.0 Ib/A of Compound E.

The superior herbicidal activity of the compound of Example 1 was also apparent at 1 8 WAT.

A distinct advantage of a herbicide is its ability to function in a wide variety of soil types.

Accordingly, data is presented in Table VI showing the herbicidal effect of the compound of Example 1 on yellow nutsedge in cotton and soybeans in a wide variety of soil types of varying organic matter and clay content. The herbicide treatments were soil incorporated with seeds planted 0.375 in. (0.95 cm) deep, with 0.25 in (0.64 cm) overhead irrigation. Observations were made 1 8 days after treatment.

Table VI OR65 OR15 Lb/A RKg/ha) Lb/A (kg/Ha) Organic Yellow Compound Type Matter% Clay% Nutsedge Cotton Soybeans Ex. 1 Ray silt loam 1.0 9.6 0.20 (0.22) 0.65 (0.73) 0.50 (0.56) Sarpy clay loam 2.3 - 0.06 (0.07) 0.85 (0.95) 0.85 (0.95) Georgeville Silty clay loam 2.9 37.0 0.11(0.12) 0.42 (0.47) 0.50 (0.56) Wabash clay loam 4.3 33.0 0.20 (0.22) 1.0 (1.12) 0.85(0.95) Drummer silty clay loam 6.0 37.0 0.20 (0.22) 0.85 (0.95) 0.78 (0.87) Florida Sand 6.8 1.8 0.24 (0.27) 0.50 (0.56) 0.43 (0.48) The data in Table VI show that the compound of Example 1 appears to be quite insensitive to soil type and organic matter content, exhibiting selective control of yellow nutsedge on both cotton and soybeans in soils ranging from 1.06.8% organic matter and 1.89.6% clay. Selectivity factors were greatest in Sarpy clay loam.

Additional tests were conducted to determine the herbicidal performance of compound of Example 1 in soils containing a large amount of organic matter. In three replicate field tests, the activity of the compound of Example 1 was tested against pigweed and lambsquarters in soybeans planted in muck soil. Compounds C, D, E and I were also tested for comparative purposes. These tests were conducted in both preplant incorporated and surface applied modes of application in muck soil containing twenty-three percent (23%) organic matter.In these tests, in both the P.P.I. and surface application modes, the compound of Example 1 exhibited the highest unit activity against lambsquarters at 4 WAT and, in the P.P.I. mode, the highest selectivity factor in soybeans, i.e., > 2.7 vs. 1.1 for each of compounds C and D; Compounds E and I were non selective at 4 WAT. All compounds were non-selective against lambsquarters at 7 WAT in either mode of herbicide application; Compound E was slightly more active than the compound of Example 1 at 7 WAT in both modes of herbicide application.Against pigweed, Compound D had the highest unit activity and selectivity factor (1.9) 7 WAT in both the P.P.I. and surface application modes; in the latter mode the selectivity factor of Compound D was almost twice that of the compound of Example 1 and Compound E; no other compounds selectively controlled pigweed 7 WAT in P. P. I. or surface application modes. The compound of Example 1 (S.F:2.0) and Compounds C and E (S.F. 1.0) for each selectively controlled pigweed 4 WAT in the P.P.I. mode.

Therefore, the above tests indicate that relative to the reference compounds, in muck soil the best selective control of lambsquarters in soybeans is provided by the compound of Example 1 applied P.P.I.; this compound had the highest unit activity and selectivity factor at 4 WAT of all compounds in the test. Moreover, the compound of Example 1 selectively controlled pigweed up to about 7 WAT in the surface application mode and up to 4 WAT in the P.P.I. mode. Compound D provided the best control of pigweed at 7 WAT in both modes of application.The relative performance of the compound of Example 1 and Compound D in muck soil should be further compared with the relative performance of these two compounds in soils having lesser organic matter, e.g., 3.0-3.5%, wherein the compound of Example 1 exhibits superior unit activity and soil longevity coupled with selectivity in soybeans, in both the surface-applied and P.P.l. modes of application as shown in Table IV.

The foregoing description has emphasized the outstanding herbicidal efficacy of the compounds of this invention to control perennial weeds and annual broadleaf weeds in soybeans and cotton.

Further, it has also been indicated above and occasionally demonstrated, e.g., in the tests involving barnyardgrass and crabgrass, that the compounds of this invention also have outstanding herbicidal activity against annular narrowleaf weeds, i.e., grasses. In fact, as will be demonstrated below with respect to certain annual grasses, compounds of this invention exhibit marked superiority vis-a-vis the most herbicidally efficaceous and/or commercially available 2-haloacetanilides of the prior art. As will be evident from test data herein, there are instances wherein a relevant prior art 2-haloacetanilide exhibits superior herbicidal efficacy vis-a-vis the invention compounds with respect to specific annual weeds under comparable conditions.However, it will also be evident from the comparative test data herein that compounds according to this invention, overall. are at least comparable to and frequently are superior, sometimes outstandingly so, to the best 2-haloacetanilides as selective herbicides to control annual and perennial narrowleaf weeds in soybeans, cotton, peanuts and other crops.

In one preemergence test in the greenhouse, the compounds of Examples 1 and 11 were compared with Compounds C and I (both commercial 2-haloacetanilides) for their relative herbicidal efficacy against annual narrowleaf weeds, i.e., grasses in soybeans. In this test, the herbicides were incorporated into the soil prior to planting seeds and obsrevations made and recorded 1 7 days after treatment; the test data are shown in Table VII and represent the averages of duplicate trials.

Table Vll GR1 5 Rate GR85 Rate (LB/A) (LB/A) Seedling Johnson- Shatter- Alexander- Wild Pro so Compound grass Cane grass Millet Red Rice Itch grass Soybeans Ex. 1 0.125 0.75 0.25 0.50 0.85 0.75 1.0 Ex.11 0.25 0.25 0.125 0.50 1.0 0.25 > 1.0 C 0.50 0.25 0.25 0.50 1.0 1.0 > 1.0 1.0 1.0 0.50 > 1.0 > 1.0 > 1.0 > 1.0 Referring to the data in Table VII, salient features to be noted are that: (1) Compound I exhibited the least unit activity and selectivity of all compounds against every weed in the test and exhibited no selectivity in soybeans with respect to wild proso millet, red rice or itchgrass; (2) Compound C was as active as the more active of the compounds of Examples 1 and 11 against shattercane and wild proso millet; (3) the compounds of Examples 1 and 11 were both superior to the prior art compounds in seedling johnsongrass and itchgrass and (4) the compound of Example 11 was more active against alexandergrass and the compound of Example 1 was more active against red rice than the prior art compounds.

Thus, to summarize the comparative test data in Table VII, one or the other or both invention compounds were as he. bicidaly efficacious as the best prior art reference compound against two annual narrowleaf weeds (shattercane and wild proso millet) and markedly superior against four narrowleaf weeds (seedling johnsongrass, alexandergrass, red rice and itchgrass). Particularly noteworthy is the outstanding unit activity of the compound of Example 1 against seedling johnsongrass (GR85=0.1 25 Ib/A (0.14 kg/ha), providing an outstanding selectivity factor of 8.0 fold in soybeans compared with a selectivity factor of > 2.0 fold for Compound C, the better of the tested prior art compounds.Similarly, the compound of Example 11 exhibited outstanding unit activity against alexandergrass and itchgrass, providing selectivity factors of > 8.0 fold and > 4.0 fold, respectively, in soybeans, compared with corresponding selectivity factors of > 4.0 fold and > 1.0 fold respectively, for Compound C.

Still another test was conducted in soybeans, this time the Texas and Fall panicum seeds were included together with the other annual grasses mentioned in the preceding test. In this test, the compounds of Examples 1 and 12 were compared for preemergence herbicidal efficacy against prior art Compounds C, D and I. The herbicides were soil incorporated and subirrigated as required. The maximum amount of herbicide used in the test was at the rate of 1.0 Ib/A, hence the exact GR85 and GR,5 rates above 1.0 Ib/A would be somewhat indeterminate. Observations were made 2 weeks after treatment. The data from this test are shown in Table VIII.

Tab!e VIII GR,5 Rate GR85 Rate FLbiAi FLb/A) Wild Com- Texas S. John. Shatt. Alex. Proso Fall Red Itch pound Pan. grass cane grass Millet Pan. Rice grass Soybeans Ex. 1 1.0 < 0.0625 0.125 0.5 0.5 < 0.0625 0.25 0.5 > 1.0 Ex.12 0.25 < 0.0625 0.125 0.125 0.5 < 0.0625 0.19 0.0625 > 1.0 C 0.5 0.0625 0.25 0.5 1.0 < 0.0625 0.25 > 1.0 > 1.0 D 0.125 0.0625 0.25 0.0625 0.5 < 0.0625 < 0.0625 0.5 1.0 1 > 1.0 0.25 0.45 0.45 1.0 < 0.0625 0.5 0.75 > 1.0 Analysis of the data in Table VIII shows that the invention compounds of Examples 1 and 12 exhibited the highest unit activities and selectivities of all compounds in the test against seedling johnsongrass and shattercane: the compound of Example 12 had the highest activity and selectivity against itchgrass and the compounds of Examples 1 and 12 shared the highest activities againt wild proso millet with Compound D and against Fall panicum with each of the prior art compounds. However, the invention compounds were more selective in soybeans than Compound D with respect to wild proso millet.

Moreover, the compound of Example 12 was the second most active compound against Texas panicum and red rice and the compound of Example 1 shared the second highest activity with Compound D against itchgrass. Compound D was the most active of the test compounds against Texas panicum, alexandergrass and red rice.

Therefore, it will be appreciated from the preceding comparative test data relative to herbicidal activity involving annual grasses, that compounds of this invention have herbicidal efficacy superior to that of the leading relevant prior art compounds against certain annual grasses, e.g., barnyardgrass, crabgrass (S.I.), shattercane and itchgrass, and equivalent or generally comparable herbicidal efficacy against others, e.g., crabgrass (surface applied), the panicums, alexandergrass and red rice.

Other tests in the greenhouse and/or in the field have shown selective control by compounds of this invention of additional weed species in soybeans, cotton and/or other crops. For example, the compound of Example 1 has been shown to selectively control purple nutsedge and giant foxtail in cotton and giant foxtail and velvetleaf in soybeans. Further, as compared with relevant acetanilide herbicides of the prior art, the compound of Example 1 has shown improved weed suppression against such resistant weeds as ragweed, morningglory and cocklebur. Additional weeds against which tne compounds of this invention have proven to be herbicidally active include Canada thistle, field bindweed, downy brome, wild buckwheat, etc.

As indicated above, compounds of this invention have been found to be efficaceous herbicides in a plurality of crops. The preceding discussion and test ciata were directed primarily to weed control in soybeans and cotton, crops of primary interest and utility herein. Additional tests have demonstrated the utility of compounds of this invention in other crops as illustrated below.

In one greenhouse test the preemergence herbicidal efficacy of the compounds of Examples 11 and 12 were tested, soil incorporated, against quackgrass in rape, snap beans, sorghum and wheat.

Both tested compounds selectively controlled quackgrass in rape and snap beans, the selectivity factor of the compound of Example 11 being 3.5 fold in both crops and that of the compound of Example 12 being 3.0 fold in both crops. In this test, both compounds were non-selective against quackgrass in sorghum and wheat.

In separate greenhouse tests, the compound of Example 1 was also tested for its herbicidal efficacy against yellow nutsedge and quackgrass, respectively, in rape, peanuts, sugarbeets, sorghum, wheat and barley; the herbicide was applied in the soil incorporated mode. In these tests, Compound D was included as a reference compound against quackgrass and Compound E was included as a reference compound against yellow nutsedge. Observations in the quackgrass test were made 19 DAT and in the yellow nutsedge test 1 8 DAT; the test data are shown in Table IX; selectivity factors for the herbicides are shown in parenthesis after the GR15 rates for the respective crops.

Table IX Weed Crop GR8s GRt5 (Lb/A) (Lb/A) Ouack Compound grass Peanuts Rape Sugarbeet Sorghum Wheat Barley Ex. 1 0.04 0.25 (6.0) 0.12(3.0) 0.25 (6.0) < 0.03 (NS) 0.05(1.0) 0.06 (1.5) D 0.03 0.03 (1.0) 0.05(1.5) 0.05 (1.5) < 0.03 (NS) 0.03(1.0) 0.1 (3.0) Yellow Nutsedge Ex. 1 0.11 0.78 (7.0) 0.43 (4.0) 0.02 (NS) 0.12 (1.0) 0.12 (1.0) 0.25 (2.0) E 0.11 0.85 (8.0) 0.78 (7.0) 0.02 (NS) 0.01. (NS) 0.04(NS) 0.12(1.0) Referring to the data in Table IX, it is seen that the compound of Example 1 and Compound D both selectively controlled quackgrass in peanuts, rape, sugarbeets, wheat and barley, but the selectivity factor of the compound of Example 1 was significantly greater than that for Compound D in peanuts, rape and sugarbeets, equivalent in wheat and less in barley. The compound of Example 1 selectively controlled yellow nutsedge in each crop in the test, except sugarbeets, whereas Compound E did not selectively control yellow nutsedge in sugarbeets, sorghum or wheat.

The high unit activity of Compounds D and E shown in Table IX is generally characteristic of the short-term greenhouse performance (i.e., 2-6 weeks) for these compounds against quackgrass and yellow nutsedge. However, as shown herein, all relevant test data, both in the greenhouse and in the field have established the uniformly superior unit activity against quackgrass and yellow nutsedge and crop selectivity of the compound of Example 1 vis-a-vis Compounds D and E for outstandingly longer periods of time.In this connection, reference should be made again: (1) to Table IV which contains comparative field test data for up to 9.5 weeks for the performance of these compounds against quackgrass and other weeds in soybeans; (neither Compound D nor E selectively controlled quackgrass in soybeans even at the 3 WAT observation); (2) to the above discussion of the comparative field test data for the performance of these compounds against yellow nutsedge and other weeds in cotton for up to nine weeks (neither Compound D nor E selectively controlled yellow nutsedge in cotton even at the 2 WAT observation); and (3) to Table V which sets forth comparative soil life data for the compound of Example 1 and Compounds D and E against yellow nutsedge and quackgrass for 3, 6, 12 and 1 8 weeks, wherein the compound of Example 1 had units of activity higher than those of Compounds D and E at 3 WAT (by orders of magnitude at the 12 WAT observation) and by an indeterminate amount at 1 8 WAT observations. It should also be mentioned here that the combined superior unit activity, soil life and crop selectivity of the compound of Example 1 vis-a-vis Compounds D and E relative to yellow nutsedge and quackgrass is also applicable to the relative performance of these compounds in many other weeds, notably, seedling johnsongrass, hemp sesbania, prickly sida, smartweed, lambsquarters, etc.

In one multi-crop/weed test, the preemergence activity of the compound of Example 1 was further tested in the field against certain annual weeds in several crops. In parallel tests the herbicides were surface applied and pre-plant incorporated. Observations were made and recorded 33 days after treatment for the pre-plant incorporated test and 34 DAT for the surface-applied tests. In both tests, the compound of Example 1 selectively controlled barnyardgrass and green foxtail in field corn, soybeans, cotton, bush beans and peanuts; lambsquarters were also controlled in soybeans.

Additionally, in the P.P.I. test, barnyardgrass and foxtail were also selectively controlled in sorghum and sweet corn.

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, other related homologs and analogs and commercial 2-haloacetanilides of the prior art. More particularly, compounds of this invention have demonstrated outstanding unit activity, soil longevity and crop safety with respect to perennials and annual broadleaf and narrowleaf weeds in soybeans, cotton, peanuts, rape, and snap beans and other crops.Still more particularly, compounds of this invention have demonstrated superior herbicidal activity against the perennials yellow nutsedge and quackgrass; annual broad leafs such as hemp sesbania, prickly sida, lambsquarters and smartweed and annual narrowleaf weeds such as barnyardgrass, crabgrass (P.P.I.), shattercane and itchgrass. Moreover, compounds of this invention have been shown to be generally comparable to the best of the relevant prior art compounds in the control of other annual grass weeds such as seedling johnsongrass, crabgrass (surface applied), the foxtails, Texas panicum, fall panicum, wild proso millet, alexandergrass and red rice and annual broadleaf weeds such as pigweed and jimsonweed.Finally, compounds of this invention have also demonstrated increased activity and suppression of resistant annual broadleaf weeds such as morningglory, cocklebur, ragweed and velvetleaf.

Toxicology studies on the compound of Example 1 have indicated the compound to be quite safe.

It was slightly toxic by ingestion (single dose OLD502,60û mg/kg), slightly toxic through single dermal applications (DLD50-5,010 mg/kg), a slight eye and skin irritant. No special handling procedures beyond normal precautions are deemed necessary.

The herbicidal compositions of this invention including concentrates which require 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 ingredient with an adjuvant including diluents, extenders, carriers and conditioning agents to provide compositions in the form of finely-divided particulate solids, granules, 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 suitabie 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, 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 nonylphenoi) 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 1.0--1 5 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 born.

Other formulations include dust concentrates 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 0.110% by weight.

Aqueous suspensions or emulsions may be prepared by stirring an aqueous mixture of a waterinsoluble 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 0.160% preferably 550% by weight of active ingredient, the upper limit being determined by the solubility limit of active ingredient 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 containing a lignin sulfonate emulsifier and a waterimmiscible 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 range from about 480 to 700 g/l of total composition, preferably 480 to 600 g/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 this invention include dimethylformide, dimethylsulfoxide, 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 matrix 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 neat expanded, particulate vermiculite and the finely-divided clays such as kaolin 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 clay and O 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:: Heterocyclic Nitrogen/Sulfur Derivatives 2-Chloro-4-ethylam ino-6-isopropyla mino-s-triazine 2-Chloro-4,6-bis(isopropylamino) -s-triazine 2-Ch loro-4,6-bis(ethylamino) -s-triazine 3-lsopropyl-1H-2,1 ,3-benzothiadiazin-4-(3H)-one 2,2-dioxide 3-Amino-l ,2,4-triazole 6,7-Dihydrodipyrido( 1,2-a ::2', 1 '-c)-pyrazidiinium salt 5-B romo-3-isopropyl-6-methyluracil 1,1 '-Dimethyl-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)-1 ,1 -dimethylurea 1 Butyl-3-(3,4-dichlorophenyl)-1 -methylurea Carbamates/Thiolcarbamates 2-Chloroallyl diethyldithiocarbamate S-(4-chlorobenzyl)N,N-diethylthiolcarbamate Isopropyl N-(3-chlorophenyl)carbamate S-2,3-dichloroallyl N,N-diisopropylthiolcarbamate Ethyl N,N-dipropylthiolcarbamate S-propyl dipropylthiolcarbamate Acetamides/Acetanilides/Anilines/Amides 2-Chloro-N,N-diallylacetamide N,N-dimethyl-2,2-diphenylacetamide N(2,4dimethyl5[[(trifIuornmethyl)suIfonyUamino]phenyI)acetamide N-lsopropyl-2-chloroacetanilide 2',6'-Diethyl-N-methoxymethyl-2-chloroacetanilide 2 '-M ethyl-6'-ethyl-N-(2-methoxyprop-2-yl)-2-chloroacetanilide cE,a,-Trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine N-(1,1 -dimethylpropynyl)-3,5-dichlorobenzamide Acids/Esters/Alcohols 2,2-Dichloropropionic acid 2-Methyl-4-chlorophenoxyacetic acid 2,4-Dichlorophenoxyacetic acid Methyl-2-[4-(2,4-dichlorophenoxy)phenoxy]propionate 3-Amino-2,5-dichlorobenzoic acid 2-Methoxy-3,6-dichlorobenzoic acid 2,3,6-Trichlorophenylacetic acid N- 1 -naphthylphthalamic acid Sodium 5-[2-chio ro-4-(trifluoromethyl)phenoxy]-2-n itrobenzoate 4,6-Dinitro-o-sec-butylphenol N-(phosphonomethyl)glycine and its C16 monoalkyl amine and alkaline metal salts and combinations thereof.

Ethers 2,4-Dichlorophenyl-4-nitrophenyl ether 2-Ch loro- -trifluoro-p-tolyl-3-ethoxy-4-nitrodiphenyl ether.

Miscellaneous 2,6-Dichlorobenzonitrile Monosodium acid methanearsonate Disodium methanearsonate Fertilizers useful in combination with the active ingredients include, for example, ammonium nitrate, urea, potash and superphosphate. Other useful additaments include materials in which plant organisms take root and grow such as compost, manure, humus, sand and the like.

Herbicidal formulations of the types described above are exemplified in several illustrative embodiments below.

I. Emulsifiable Concentrates Weight Percent A. Compound of Example No. 1 50.0 Calcium dodecylbenzene sulfonate/polyoxyethylene ethers blend (e.g., Atlox 3437F and Atlox 3438F) 5.0 Monochlorobenzene 45.0 100.00 B. Compound of Example No. 12 85.0 Calcium dodecyl sulfonate/alkylaryl poiyether alcohol blend 4.0 C9 aromatic hydrocarbons solvent 11.0 100.00 C. Compound of Example No. 13 5.0 Calcium dodecylbenzene sulfonate/polyoxyethylene ethers blend (e.g., Atlox 3437F) 1.0 Xylene 94.0 100.00 II. Liquid Concentrates Weight Percent A. Compound of Example No.1 10.0 Xylene 90.0 100.00 B. Compound of Example No. 2 85.0 Dimethyl sulfoxide 15.0 100.00 C. Compound of Example No. 3 50.0 N-methylpyrrolidone 50.0 100.00 Weight Percent D.Compound of Example No. 4 5.0 Ethoxylated castor oil 20.0 Rhodamine B .5 Dimethyl formamide 74.5 100.00 Ill. Emulsions Weight Percent A. Compound of Example No. 1 40.0 Polyoxyethylene/polyoxypropylene block copolymer with butanol (e.g., TergitolXH) 4.0 Water 56.0 100.00 B. Compound of Example No. 5 5.0 Polyoxyethylene/polyoxypropylene block copolymer with butanol 3.5 Water 91.5 100.0 IV. Wettable Powders Weight Percent A. Compound of Example No. 1 25.0 Sodium lignosulfonate 3.0 Sodium N-m ethyl-N-o leyl-taurate 1.0 Amorphous silica (synthetic) 71.0 100.00 B. Compound of Example No. 6 80.0 Sodium dioctyl suifosuccinate 1.25 Calcium lignosulfonate 2.75 Amorphous silica (synthetic) 16.00 100.00 C.Compound of Example No.7 10.0 Sodium lignosulfonate 3.0 Sodium N-methyl-N-oleyl-taurate 1.0 Kaoiinite clay 86.0 100.00 V. Dusts Weight Percent A. Compound of Example No. 1 2.0 Attapulgite 98.0 100.00 B. Compound of Example No. 8 60.0 Montmorillonite 40.0 100.0 C. Compound of Example No. 9 30.0 Bentonite 70.0 100.00 Weight Percent D. Compound of Example No.11 1.0 Diatomaceous earth 99.0 100.00 VI. Granules Weight Percent A. Compound of Example No.1 15.0 Granular attapulgite (20/40 mesh) 85.0 100.00 B. Compound of Example No. 12 30.0 Diatomaceous earth (20/40) 70.0 100.00 C. Compound of Example No.13 0.5 Bentonite (20/40) 99.5 100.00 D. Compound of Example No. 14 5.0 Pyrophyllite (20/40) 95.0 100.00 Vll. Microcapsules A.Compound of Example No. 1 encapsulated in polyurea shell wall 49.2 Sodium lignosulfonate (e.g. Reax 880B) 0.9 Water 49.9 100.00 B. Compound of Example No. 12 encapsulated in polyurea shell wall 10.0 Potassium lignosulfonate (e.g., Reax C-21) .5 Water 89.5 100.00 C. Compound of Example No. 13 encapsulated in polyurea shell wall 80.0 Magnesium salt of lignosulfate (Treax LTM) 2.0 Water 18.0 100.00 When operating in accordance with the present invention, effective amounts of the acetanilides of this invention are applied to the soil containing the plants, or are incorporated into aquatic media 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 dusters, boom and hand sprayers and spray dusters.

The compositions can also be applied from airplanes as a dust or a spray because of their effectiveness at low dosages. The application of herbicidal compositions to aquatic plants is usually carried out by adding the compositions to the aquatic media in the area where control of the aquatic plants is desired.

The application of an effective amount of the compounds of this invention to the locus of undesired weeds is essential and critical for the practice of the present invention. The exact amount of active ingredient to be employed is dependent upon various factors, including the plant species and stage of development thereof, the type and condition of soil, the amount of rainfall and the specific acetanilide employed. In selective preemergence application to the plants or to the soil a dosage of from 0.02 to about 11.2 kg/ha, preferably from about 0.04 to about 5.60 kg/ha, or suitably from 1.12 to 5.6 kg/ha of acetanilide is usually employed. Lower or higher rates may be required in some instances. One skilled in the art can readily determine from this specification, including the above example, the optimum rate to be applied in any particular case.

The term "soil" is employed in its broadest sense to be inclusive of all conventional "soils" as defined in Webster's New International Dictionary, Second Edition, Unabridged (1961). Thus the term refers to any substance or media in which vegetation may take root and grow, and includes not only earth but also compost, manure, muck, humus, sand and the like, adapted to support plant growth.

Although the invention is described with respect to specific modifications, the details thereof are not to be construed as limitations except to the extent indicated in the following claims.

Claims (45)

Claims

1. A compound of the formula

wherein R is ethyl, n-propyl, isopropyl, isobutyl, sec-butyl, cyclopropylmethyl, allyl or propargyl; R, is ethyl, ethyl, n-propyl or isopropyl and R2 is hydrogen, methyl or ethyl; provided that; when R2 is hydrogen, R, is ethyl and R is allyl; when R2 is ethyl, R, is methyl and R is isopropyl; when R1 is methyl, R is ethyl, isopropyl, isobutyl, sec-butyl or cyclopropylmethyl; when R1 is ethyl, R is sec-butyl, allyl or propargyl; when R1 is n-propyl, R is ethyl and when R1 is isopropyl, R is ethyl or n-propyl.

2. Compound according to Claim 1 which is 2'-methoxy-6'-methyl-N-(isopropoxymethyl)-2chloroacetanilide.

3. Compound according to Claim 1 which is 2'-methoxy-6'-methyl-N-(ethoxymethyl)-2chloroacetanilide.

4. Compound according to Claim 1 which is 2'-methoxy-6'-methyl-N-(1-methylpropoxymethyl)2-chloroacetanilide.

5. Compound according to Claim 1 which is 2'-ethoxy-6'-methyl-N-(allyloxymethyl)-2chloroacetanilide.

6. Compound according to Claim 1 which is 2'-ethoxy-6'-methyl-N-(propargyloxymethyl)-2chloroacetanilide.

7. Compound according to Claim 1 which is 2'-ethoxy-6'-methyl-N-(1-methylpropoxymethyl)-2chloroacetanilide.

8. Compound according to Claim 1 which is 2'-n-propoxy-6'-methyl-N-(ethoxymethyl)-2chloroacetanilide.

9. Compound according to Claim 1 which is 2'-isopropoxy-6'-methyl-N-(ethoxymethyl)-2chloroacetanilide.

10. Compound according to Claim 1 which is 2'-isopropoxy-6'-methyl-N-(n-propoxymethyl)-2chloroacetanilide.

11. Compound according to Claim 1 which is 2'-ethoxy-N-(allyloxymethyl)-2-chloroacetanilide.

12. Compound according to Claim 1 which is 2'-methoxy-6'-ethyl-N-(isopropoxymethyl)-2chloroacetanilide.

1 3. A herbicidal composition comprising an adjuvant and a herbicidally effective amount of a compound having the formula

wherein R is ethyl, n-propyl, isopropyl, isobutyl, sec-butyl, cyclopropylmethyl, allyl or propargyl; R1 is methyl, ethyl, n-propyl or isopropyl and R2 is hydrogen, methyl or ethyl; provided that; when R2 is hydrogen, R, is ethyl and R is allyl; when R2 is ethyl, R, is methyl and R is isopropyl; when R, is methyl, R is ethyl, isopropyl, isobutyl, sec-butyl or cyclopropylmethyl; when R, is ethyl, R is sec-butyl, allyl or propargyl; when R, is n-propyl, R is ethyl and when R, is isopropyl, R is ethyl or n-propyl.

14. Composition according to Claim 13 wherein said compound is 2'-methoxy-6'-methyl-N (isopropoxymethyl)-2-chloroacetanilide.

1 5. Composition according to Claim 13 wherein said compound is 2'-methoxy-6'-methyl-N (ethoxymethyl )-2-chloroaceta nilide.

16. Composition according to Claim 13 wherein said compound is 2'-methoxy-6'-methyi-N-(l- methylpropoxymethyl)-2-chloroacetanilide.

1 7. Composition according to Claim 13 wherein said compound is 2'-ethoxy-6'-methyl-N (allyloxymethyl)-2-chloroacetanilide.

18. Composition according to Claim 13 wherein said compound is 2'-ethoxy-6'-methyl-N (propargyloxymethyl)-2-chloroacetanilide.

19. Composition according to Claim 13 wherein said compound is 2'-ethoxy-6'-methyl-N-(1methylpropoxymethyl)-2-chloroacetanilide.

20. Composition according to Claim 13 wherein said compound is 2'-n-propoxy-6'-methyl-N (ethoxymethyl)-2-chloroacetanilide.

21. Composition according to Claim 13 wherein said compound is 2'-isopropoxy-6'-methyl-N (ethoxymethyl)-2-ch loroacetanilide.

22. Composition according to Claim 13 wherein said compound is 2'-isopropoxy-6'-methyl-N-(npropoxymethyl)-2-chloroacetaniiide.

23. Composition according to Claim 13 wherein said compound is 2'-ethoxy-N-(allyloxymethyl)2-chloroacetanilide.

24. Composition according to Claim 13 wherein said compound is 2'-methoxy-6'-ethyl-N (isopropoxymethyl)-2-chloroacetan ilide.

25. Method for combatting undesirabie plants associated with crop plants which comprises applying to the locus of said plants a herbicidally effective amount of a compound having the formula

wherein R is ethyl, n-propyl, isopropyl, isobutyl, sec-butyl, cyclopropylmethyl, allyl or propargyl; R, is methyl, ethyl, n-propyl or isopropyl and R2 is hydrogen, methyl or ethyl; provided that; when R2 is hydrogen, R, is ethyl and R is allyl; when R2 is ethyl, R, is methyl and R is isopropyl; when R, is methyl, R is ethyl, isopropyl, isobutyl, sec-butyl or cyclopropylmethyl; when R1 is ethyl, R is sec-butyl, allyl or propargyl; when Rl is n-propyl, R is ethyl and when R, is isopropyl, R is ethyl or n-propyl.

26. Method according to Claim 25 wherein said compound is 2'-methoxy-6'-methyl-N (isopropoxymethyl)-2-chloroa ceta nilide.

27. Method according to Claim 25 wherein said compound is 2'-methoxy-6'-methyl-N (ethoxymethyl)-2-chloroacetanilide.

28. Method according to Claim 25 wherein said compound is 2'-methoxy-6'-methyl-N-(1 methyipropoxymethyl)-2-chloroacetanilide

29. Method according to Claim 25 wherein said compound is 2'-ethoxy-6'-methyl-N (aliyloxymethyl)-2-chloroacetanilide.

30. Method according to Claim 25 wherein said compound is 2'-ethoxy-6'-methyl-N (propargyioxymethyl)-2-chloroaceta nilide.

31. Method according to Claim 25 wherein said compound is 2'-ethoxy-6'-methyl-N-(1methylpropoxymethyl)-2-chloroaceta nilide.

32. Method according to Claim 25 wherein said compound is 2'-n-propoxy-6'-methyl-N (ethoxymethyl)-2-chloroacetanilide.

33. Method according to Claim 25 wherein said compound is 2'-isopropoxy-6'-methyl-N (ethoxymethyl)-2-chlo roaceta nilide.

34. Method according to Claim 25 wherein said compound is 2'-ethoxy-N-(allyloxymethyl)-2chloroacetanilide.

35. Method according to Claim 25 wherein said compound is 2'-methoxy-6'-ethyl-N (isopropoxymethyl)-2-ch loroaceta nilide.

36. Method according to Claim 25 wherein said crops are soybeans, cotton, peanuts, rape, bush beans, sugarbeets, sorghum, wheat or barley.

37. Method according to Claim 36 wherein said undesirable plants are perennial grass and sedge weeds and annual weeds.

38. Method according to Claim 37 wherein said perennial weeds are quackgrass and yellow nutsedge.

39. Method according to Claim 37 wherein said annual weeds are broadleaf weeds.

40. Method according to Claim 39 wherein said broadleaf weeds are prickly sida, hemp sesbania, pigweed, smartweed, lambsquarters, and jimsonweed.

41. Method according to Claim 37 wherein said annual weeds are grasses.

42. Method according to Claim 41 wherein said grasses are foxtails, barnyardgrass, crabgrass, panicums, shattercane, alexandergrass, red rice and itchgrass.

43. Method according to any of Claims 361 or 42 wherein said compound is 2'-methoxy-6' methyl-N-(isopropoxymethyl)-2-chloroacetanilide.

44. Method for selectively controlling the growth of weeds in soybeans, cotton, peanuts, rape, snap beans, sugarbeets, sorghum, wheat or barley which comprises applying to the locus of said weeds a herbicidally-effective amount of 2'-methoxy-6'-methyl-N-(isopropoxymethyl)-2chloroacetanilide.

45. Method for suppressing weed stands of ragweed, imorningglory, cocklebur and velvetleaf which comprises applying to the locus thereof a herbicidally-effective amount of 2'-methoxy-6' methyl-N-(isopropoxymethyl)-2-chloroacetanilide.