US3404976A - Herbicidal composition and method - Google Patents

Description

United States Patent O 3,404,976 HERBICIDAL COMPOSITION AND METHOD John F. Olin, Ballwin, Mo., assignor to Monsanto Company, St. Louis, M0,, a corporation of Delaware No Drawing. Application Feb. 1, 1966, Ser. No. 523,923, which is a continuation-in-part of applications Ser. No. 134,131, Ser. No. 134,158, and Ser. No. 134,160, Aug. 28, 1961. Divided and this application Nov. 21, 1966, Ser. No. 608,712

50 Claims. (Cl. 71-118) The portion of the term of the patent subsequent to Sept. 5, 1984, has been disciairned and dedicated to the Public ABSTRACT OF THE DISCLOSURE Compositions comprising alpha-haloacetanilides of the formula NH CHizX wherein R is tertiary alkyl of at least 4 and not more than carbon atoms, R is hydrogen, halogen, primary, secondary, and tertiary alkyl of not more than 8 carbon atoms or alkoxy of not more than 4 carbon atoms, R is hydrogen, primary and secondary alkyl of not more than 6 carbon atoms, chloride or nitro, and X is chloride, bromide or iodide, provided that one and not more than one of R and R is always hydrogen unless R is primary alkyl or secondary alkyl in which case R is as defined above and further provided that R is always primary alkyl or secondary alkyl when R is chloride or nitro, exhibit phytotoxic utility.

This application is a division of co-pending application Ser. No. 523,923, filed Feb. 1, 1966, which, in turn, is a continuation-in-part of applications Ser. No. 134,131, Ser. No. 134,158 and Ser. No. 134,160, all filed Aug. 28, 1961 and now abandoned.

This invention relates to a-haloacetanilides which are useful as biocides, particularly phytotoxicants, and to processes for preparing them. This invention further relates to phytotoxic compositions and to methods of controlling or modifying the growth of plants. r

The term phytotoxicant as used herein and in th appended claims means materials having a modifying effect upon the growth of plants. Such modifying effects include all deviations from natural development, for example, killing, retardation, defoliation, desiccation, regulation, stunting, tillering, stimulation, dwarfing, and the like. In like manner, phytotoxic and phytotoxicity are used to identify the growth modifying activity of the compounds and compositions of this invention.

The term plant as used herein and in the appended claims means germinant seeds, emerging seedlings and established vegetation including the roots and aboveground portions.

The novel a-haloacetanilides of this invention are represented by the formula wherein R is tertiary alkyl having from 4 to 10 carbon atoms, R is selected from the group consisting of H, halogen (Cl, Br, I and F), primary alkyl having from 1 to 8 carbon atoms, secondary alkyl of not more than 8 carbon atoms, tertiary alkyl of not more than 8 carbon atoms and alkoxy having from 1 to 4 carbon atoms, R is selected from the group consisting of H, primary alkyl having from 1 to 6 carbon atoms, secondary alkyl of not more than 6 carbon atoms, chloride and nitro and X is selected from the group consisting of chloride, bromide and iodide, provided that one and not more than one of R and R is always H unless R is primary alkyl or secondary alkyl in which case R is as defined above and further provided that R is always primary alkyl or sec"- ondary alkyl when R is chloride or nitro.

In the above formula the tertiary alkyl of R can be, for example, tert-butyl, tert-amyl, 1,1,2-trimethylpropyl, 1,1-dirnethylbutyl, 1,1-dimethylamyl, 1,1,2-trimethylbutyl, 1,1,3 -trimethylbutyl, 1,1,3,3-tetramethylbutyl, 1,1,2,3-tetrarnethylbutyl, 1,1,2,2-tetramethylbutyl, and 1,1-dimethyloctyl groups.

In the formula R can be H, Cl, Br, I, F, alkyl such as methyl, ethyl n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-amyl, n-hexyl, nheptyl, n-octyl, and the various homologues and isomeric forms of alkyl having not more than 8 carbon atoms or alkoxy such as methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, secbutoxy and tert-butoxy. In the formula R can be H, chloride, nitro and the primary alkyl and secondary alkyl listed above for R which have not more than 6 carbon atoms.

The a-halocetanilides of this invention can be prepared by haloacetylation of suitable nuclear-substituted aromatic amines. Suitable nuclear-substituted aromatic amines can be prepared, for example, by the process disclosed in application Ser. No. 824,455, filed July 2, 1959, and now abandoned. The haloacetylating agent is preferably either a haloacetic anhydride, such as chloroacetic anhydride or a haloacetyl halide, such as chloroacetyl chloride, bromoacetyl bromide, or the like. The choice of haloacetylating agent is determined to some extent by the nature of the ortho substitution of the aromatic amine to be acetylated. Thus, the haloacetic anhydride is ordinarily used with a difiicultly acetylated amine such as 2,6-di-tert-butylamine but it is usually preferrd to use a haloacetyl halide to acetylate the more reactive amines.

The haloacetylation reaction is preferably conducted in the presence of a suitable organic medium. The organic medium must be anhydrous if the acetylating agent is a haloacetic anhydride. However, either anhydrous media or media containing water can be used with haloacetyl halide acetylating agents. Suitable organic media for use with either acetylating agent include, for example, benzene, diethyl ether, hexane, methylethyl ketone, chlorobenzene, toluene, chloroform, and the xylenes. Preferably an acid acceptor is present in the reaction zone to neutralize the acid formed. Suitable acid acceptors for anhydrous systems include the aromatic amine reactants, which can be present in the reaction zone in an amount greater than that required for the acetylation, tertiary amines and pyridine. Acid acceptors in aqueous systems include alkali or alkaline earth hydroxides and alkali or alkaline earth metal carbonates or bicarbonates.

The haloacetylation reaction is generally carried out at temperatures below room temperature, and is preferably carried out in the range of from about 0 C. to about 15 C. The reaction is preferably carried out at atmospheric pressure although subatmospheric pressure and super-atmospheric pressure can be used. Although haloacetylation can be carried out using equimolar amounts of reactants, it is preferred that from 2 to 5% of an excess of the acetylating agent be used. The acet- Patented Oct. 8, 1968 anilide products can be separated from the reaction mixture by methods well known to those skilled in the art, for example, distillation or fractional crystallization from the reaction medium or from solvents.

The nitro-substituted ot-haloacetanilides of this invention are prepared by nitration of an ortho di-substituted a-haloacetanilide. Preferably, nitric acid is used as nitrating agent and the reaction is carried out at low temperature, ordinarily at a temperature below In accordance with this invention it has been found that the growth of germinant seeds, emerging seedlings, and established vegetation can be controlled and modified by exposing the seeds, emerging seedlings, or the roots or above-ground portions of established vegetation to the action of an effective amount of one or more of the a-haloacetanilides of this invention. These compounds are effective as general phytotoxicants including postemergent phytotoxicants and pre-emergent phytotoxicants, but their most outstanding utility is as pre-emergent phytotoxicants. Furthermore, these compounds are characterized by a broad spectrum of herbicidal or phytotoxic activity, i.e. they modify the growth of a wide variety of plant systems including both broadleaf and grass plants. For the sake of brevity and simplicity, the term active ingredient will be used hereinafter in this specification to describe the novel a-haloacetanilides of this invention.

The phytotoxic or herbicidal compositions of this invention contain at least one active ingredient and a material referred to in the art as a phytotoxic adjuvant in liquid or solid form. The phytotoxic 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 finelydivided particulate solids, granules, pellets, solutions and aqueous dispersions or emulsions. Thus the active ingredient can be used with an adjuvant such as a finelydivided particulate solid, a solvent liquid of organic origin, water, a wetting agent, dispersing agent, an emulsifying agent or any suitable combination of these.

The term phytotoxic composition as used herein and in the appended claims is intended to mean not only compositions in a suitable form for application but also concentrated compositions which require dilution or extension with a suitable quantity of liquid or solid adjuvant prior to application.

The a-haloacetanilides of this invention are also useful as fungicides, insecticides, nematocides, algecides, bactericides, bacteriostats, and fungistats.

The following examples will illustrate the invention. In these examples, as well as in the specification and appended claims, parts and percent are by weight unless otherwise indicated.

EXAMPLE 1 In this example, 2-tert-butyl-2,6-dichloroacetanilide was prepared by heating 10.4 g. (0.1 mole) of 2-tertbutyl-6-chloroaniline and 29 ml. of chloroacetic anhydride under reflux for 10 minutes. Thereafter, 100 ml. of water was added to the reaction mixture and the solvents removed by distillation. The residue was cooled to effect crystallization of the product which was recovered, washed with water, and crystallized from dilute methanol to obtain 19 g. of the 2'-tert-butyl-2,6-dichloroacetanilide which is a colorless solid having a melting point of 131.5-2" C.

EXAMPLE 2 Into a 1-liter reaction flask were placed 0.2 mole of 2-tert-butyl-S-methylaniline, 400 g. of benzene and 40 g. of pyridine. Thereafter, 0.22 mole of chloroacetyl chloride was added slowly with stirring over a period of 30 minutes while maintaining the temperature at 12 to 23 C. Upon completion of the addition of the chloroacetyl chloride the reaction mixture was stirred for an additional minutes. At the end of this time, the reaction mixture was diluted with 250 ml. of water. The oil layer formed was separated and washed first with 300 ml. of 3 hydrochloric acid and then twice with warm water. The solvents were removed by evaporation under a hood and the syrup obtained cut-back with 200 ml. of heptane. The heptane solution was cooled to effect crystallization of the product. Recrystallization from dilute methanol gave 41 g. of 2-tert-butyl-2-chloro-5'-methylacetanilide which is a light-tan colored material having a melting point of 102-5 C. Analysis of this product was found to be 15.22% chlorine as compared with the calculated value of 14.79% chlorine.

EXAMPLE 3 Into a reaction flask were placed 0.2 mole of 2-tertbutyl-S-methylaniline, 400 g. of benzene and 40 g. of pyridine. Thereafter, 0.22 mole of bromoacetyl bromide was added with stirring over a period of 30 minutes while maintaining the temperature at 5 to 15 C. Upon completion of the addition of the bromoacetyl bromide, the reaction mixture was stirred an additional 15 minutes. At the end of this time, the reaction mixture was diluted With 250 ml. of water. The oil layer formed was eparated and washed with 200 ml. of warm water. The reaction mixture was then diluted with an equal volume of heptane and cooled to effect crystallization of the product. Recrystallization of the product gave 36 g. of 2-bromo-2-tert-butyl-5'-methylacetanilide which is a cream-colored solid material having a melting point of 1335 C. Analysis of the product was found to be 28.30% bromine as compared with the calculated value of 28.12% bromine.

EXAMPLE 4 In this example, 2'-tert-butyl-2-chloro-6'-methyl-5- nitroacetanilide was prepared by nitration of 2-tertbutyl-2-chloro-6'-methylacetanilide which was prepared from 2-tert-butyl-6-methylaniline and chloroacetyl chloride. In preparation of the 2-tert-butyl-2-chloro-6-methylacetanilide, 163 g. (1.0 mole) of 2-tert-butyl-6-methylaniline, 100 g. of potassium carbonate, 100 ml. of water, 400 g. of ice, 200 ml. of benzene, and 100 ml. of diethyl ether were placed in a 2-liter reaction flask. Thereafter, 120 g. (1.05 mole) of chloroacetyl chloride in 100 ml. of benzene Was added slowly to the reaction flask with stirring over a period of 35 minutes. After about of the addition of .the chloroacetyl chloride was completed during which time the temperature was maintained from 46 C., 200 ml. of benzene was added to the reaction flask and the addition of the chloroacetyl chloride continued with the temperature maintained at 22 C. Thereafter, the oil phase in the reaction mixture was separated, washed with 1 liter of warm water, diluted with 250 ml. of water, and evaporated under a hood to remove the solvents. The residue was taken up in methanol and crystallization effected to obtain the 2'-tert-butyl-2-chloro- 6'-methylacetanilide having a melting point of 113.8- 114.2 C.

In the nitration step, 84 g. of the 2'-tert-butyl-2-chloro- 6'-methylacetanilide was pulverized and placed in a 1-liter flask with 68 ml. of acetic acid and 85 ml. of acetic anhydride. After cooling the contents of the flask to 10 C., 18 ml. of nitric acid in 55 ml. of acetic acid was added slowly over a period of 40 minutes while maintaining the temperature at 14 to 10 C. Upon completion of the addition of the nitric acid, the contents of the-flask were stirred for a period of 2 hours at a temperature of -10 C. and then 1 hour at a temperature in the range of from 10 to 0 C. At the end of this time, the reaction mixture was cooled with ice and the solid material formed separated and recovered by filtering and washing with water. The product was crystallized twice from 90% methanol to obtain 28 g. of the 2'-tert-butyl-2-chl0ro-6-methyl-5'-nitroacetanilide which is a cream-colored solid having a melting point of 1645 C. Analysis of this product was found to be 12.51%

EXAMPLE 5 In this example 2-bromo-2-tert-butyl-5'-chloro-6'- methylacetanilide was prepared from bromoacetyl bromide and 2-tert-butyl-5-chloro-6-rnethylaniline which was prepared by alkylation of 3-chloro-2-methylaniline with isobutene using a clay catalyst. In the bromoacetylation step, 99 g. (1.5 mole) of 2-tertabutyl-5-chloro-6-methylaniline was dissolved in 400 ml. of benzene and the mixture heated to boiling under reflux. Then, 125 g. of bromoacetyl bromide was added over a period of about minutes. Thereafter, the reaction mixture was heated for a period of 17 hours. At the end of this time the reaction mixture was cooled and the solid precipitate which formed was recovered by filtration. The product was crystallized from methanol to obtain 95' g. of the 2-bromo'-2'- tert-butyl-2-chloro-6-methylacetanilide which is an offwhite solid having a melting point of 178-9 C. Analysis of this product was found to be 25.28% bromine as compared with the calculated value of 25.08% bromine.

EXAMPLE 6 C. Upon completion of the addition of the bromoacetyl.

bromide, the reaction mixture was stirred for an additional 10 minutes. At the end of this timethe reaction mixture was heated to 40C. with stirring and maintained at that temperature for /2 hour. At the end of. this time, the reaction mixture was chilled to 10 C. and filtered. The filter cake was recovered and washed with heptane followed by several washings with water.

The filter cake was air dried to obtain 216 g. of 2'-tertbutyl-2-bromo-6-methoxyacetanilide as a white powder having a melting point of 147.5l48.5.C. Analysis of the product was found to be 26.71% bromine as compared with a calculated value of 26.61% bromine.

Following substantially the same procedure as in the foregoing examples and using the appropriate reactants, the following compounds are prepared.

Example No.:

7 2-tert-butyl-2,5'-dichloro 6 methylacetanilide. Y 8 2'-tert-butyl-2-chloro-5,6' dimethylacetanilide.

9..-- 2-chloro-5',6'-dimethyl 2' 1,1 dimethylpropyl) acetanilide.

10 2-bromo-2'-tert-butyl 5,6 dimethylacetanilide.

1l 2'-tert-butyl-2-iodo-5',6'-dimethylacetanilide.

12- -2-chloro-5',6-dimethyl-2'-(1,1-dirnethylbutyl)- acetanilide. 13 2-bromo5,6'-dimethyl 2 (1,1 dimethylbutyl) acetanilide.

l4 2'-tert-butyl-2chloro-6'-methylacetanilide.' l5 2-tert-butyl-2-chloro-6'-ethylacetanilide. l6 2'-tert-amyl-2-chloro-6f-rnethylacetanilide. 7 17. .2'-tert-butyl-2-chloro-6-isopropylacetanilide. 18- ..2-bromo-2'-tert-butyl-6'-methylacetanilide. 19- 2-tert-amyl-2-bromo-6-methylacetauilide.

20 2-bromo-2'-(1,1-dimethylbutyl) 6 methyl aniline.

21 2-chloro-2'-methyl 6(1,1,3,3 1 tetramethylbutyl) acetanilide.

22- 2-chloro-2',6-di-tert-butylacetanilide. 23 -2-bromo 2',6-di-tert-butylacetanilide.

24- ..2'-tert-butyl-2-iodo-6-methylacetanilide. 25. 2'-tert-butyl-6'-ethyl-2-iodoacetanilide. 26 ..2-bromo-2'-tert-butyl-6'-isopropylacetanilide. 27 2-ch1oro-2'-(l,l-dimethylbutyl) 6' methylacetanilide. 28 2-bromo-2'-tert-butyl-6'-ethylacetanilide. 29-.. .2-tert-butyl-2-chloro-6-methoxyacetanilide. 30- 2'-tert-butyl-2-iodo-6'-methoxyacetanilide.

EXAMPLE 31 The pre-emergence phytotoxic activity of representatlve a-haloacetanilides of this invention was determined In greenhouse tests in which a specific number of seeds of a number of different plants, each representing a principal botanical type, were planted in greenhouse flats. A good grade of top soil was placed in either 9 /2" or 5%" x 2%" or 9" x 13" x 2" aluminum pans and compacted in a depth of /s-inch from the top of the pan. On top of the soil were placed five seeds of each of radish, morning glory, and tomato; 10 seeds of each of sugar beet, sorghum, and brome grass; 20 seeds each of wild buckwheat, giant foxtail, rye grass, and wild oat; approximately 20 to 30 (a volume measure) of each of pigweed and crab grass; and either 2 or 3 seeds of soybean. Two different type plantings were made; one wherein the phytotoxic composition was applied to the surface of the soil and the other wherein the phytotoxic composition was admixed with or incorporated in the top layer of soil. In the surface application plantings, the seeds were arranged with 3 soybean seeds across the center of the large aluminum pan, the monocotyledon or grass seeds scattered randomly over one-third of the soil surface, and the dicotyledon or broadleaf seeds scattered randomly over the remaining one-third of the soil surface at the other end of the pan. The seeds were then covered with %-inch of prepared soil mixture and the pan leveled. In the soil incorporation plantings, 450 g. of prepared soil mixture was blended with the phytotoxic composition in a separate mixing container for covering the seeds which were planted in the smaller of the two aluminum pans. The seeds in this planting were arranged with a soybean seed planted in diagonal corners and the monocotyledon seeds and the dicotyledon seeds each scattered randomly over one-half of the soil surface. The phytotoxicant-incorporated soil mixture was used to cover the seeds. The phytotoxic composition wasv applied in the surface-application plantings prior to the watering of the seeds. This application of phytotoxic composition was made by spraying the 7 surface of the soil with an acetone solution containing a suflicient quantity of the candidate chemical to obtain the desired rate per acre on the soil surface. The watering of the seeds in both type plantings was accomplished by placing the aluminum pans in a sand bench having /2- inch depth of water thereon and permitting the soil in the pans to absorb moisture through the perforated bottom of the pans.

' The planted pans were thereafter placed on a wet sand bench in a greenhouse and maintained there for 14 days under ordinary conditions of sunlight and watering. At the end of this time, the plants were observed and the results recorded by counting the number of plants of each species which germinated and grew. The phytotoxic activity index is based on the average percent germination of each seed lot. The activity index is converted to a relative numerical scale for the sake of brevity and simplicity in the examples. The pre-emergent phytotoxic activity index used in this example is defined as follows:

Average Percent Numerical Phytotoxic Activity Germination Scale 76-100 0 N o phytotoxieity. 51-75 1 Slight phytotoxieity.

2 Moderate phytotoxicity. 3 Severe phytotoxicity.

The pre-emergence phytotoxic activity of the a-halo- AGeneral Grass B-General Broadleaf CMorning Glory ICrab Grass K-Pigweed L-Soybean M-Wild Buckwheat N-Tomato O-Sorghum Individual phytotoxic ratings for each plant type are D-Wilcl Oats reported in Table 1. In addition, the total phytotoxic rat- E--Brome Grass ing for all grass plants and the total phytotoxic rating for F-Rye Grass 10 all broadleaf plants are also reported in Table I. For GRadish grasses, the maximum total is 18 for the 6 grass plants HSugar Beet at ratings of 3. For broadleafs, the maximum total is 21 I-Foxtail for the 7 broadleaf plants at rating of 3.

TABLE I.P1'c-Emergence Phototoxic Activity Plant Total Phyto- Ratc, toxic Rating Compound lbJacre Comments B C D E F G 1-1 I J K L M N Grass B{oa;1-

2-tert-butyl-2-cl11oro-6-methy1acetanilide 25 3 3 3 3 3 3 3 3 3 3 3 3 18 21 5 3 3 3 3 3 3 '3 3 3 3 3 3 18 21 1 3 3 3 3 3 3 3 3 3 3 3 3 18 21 0. 3 3 3 3 1 2 3 0 1 3 3 3 3 15 Z 13 0. 05 2 0 0 0 0 3 0 0 3 3 2 0 9 3 2 2-tert-butyl-2-chloro6-ethylacetanilide 25 3 3 3 3 3 3 3 3 3 3 3 3 18 21 5 3 3 3 3 3 3 3 3 3 3 3 3 18 3 18 1 3 3 3 3 3 3 2 3 3 3 3 3 l8 3 17 0. 3 2 0 l 2 0 3 0 0 2 3 0 2 12 3 A 0. 05 2 0 2 0 0 3 0 0 3 3 0 0 0 0 3 2 2-chl0r0-2-(Ll-dimetliylpropyl)-G-metl1yl 5 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 18 21 acetanilide. 0. 25 3 1 1 2 2 3 0 1 3 3 3 3 0 1 2 l5 9 0. 07 2 0 1 0 2 3 0 0 3 3 2 O 0 2 v 0 11 5 2'-tert-butyl-2-chloro-6-isopropylacetanilide. 5 3 0 0 3 3 3 (l 0 3 3 3 0 O 0 3 18 3 1 2 1 1 0 0 3 0 3 3 3 3 0 0 2 0 9 9 0. 25 1 1 0 1 1 1 0 1 2 3 3 0 0 2 0 8 6 2-brom0-2-tert-buty1-6-1nethylacetanilide 5 3 3 0 3 3 3 3 3 3 3 3 1 2 3 3 18 15 1 3 3 2 3 3 3 2 3 3 3 3 0 2 3 3 13 15 0. 25 3 2 0 1 3 3 2 3 3 3 3 0 0 2 3 16 0. 02 3 0 0 2 0 2 0 0 3 3 0 0 0 0 3 13 0 2-tert-amyl-2-bromo-(Y-methylacotanilide 5 3 2 0 3 3 3 2 3 3 3 3 3 0 3 3 18 14 1 3 2 0 3 3 3 2 3 3 3 3 0 3 3 3 18 14 0. 25 3 3 0 2 3 3 3 3 3 3 3 3 0 3 3 17 0.02 2 0 0 1 0 3 0 0 3 3 1 0 O 0 2 12 1 2-b1'om0-2(l,l-dimethylbutyl)-ti-1netl1ylac0t 5 3 2 0 3 3 3 3 3 3 3 3 1 0 3 3 18 13 anilide. I 1 3 2 0 3 3 3 3 2 3 3 3 0 2 3 3 18 13 0.25 3 1 0 1 0 3 1 1 3 3 3 0 1 1 3 13 7 1 0. 05 2 0 0 0 1 2 0 1 2 3 2 0 0 0 2 10 3 2-cl1loro-2-methyl-6-(1,1,3,3-tetramethylbu l)- 25 3 0 0 3 0 3 0 0 3 3 3 0 O 0 3 15 3 acetanilide. 5 3 0 1 2 0 3 0 1 3 3 3 0 0 0 3 14 5 1 2 0 0 0 0 3 0 0 3 3 3 0 1 0 0 0 4 2-bromo-2,6-di-tert-butylacetanilide 25 3 0 0 3 0 3 0 0 3 3 3 0 0 0 3 15 3 5 3 0 1 2 0 3 0 1 3 3 3 0 0 0 3 14 5 1 2 O 0 0 0 3 0 0 3 3 3 0 1 0 0 9 4 2-tert-butyl-2-i0do'6-methylacetanilide 5 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 18 21 I 1 3 3 3 3 3 3 3 3 3 3 3 3 2 3 3 18 0. 2 3 3 0 0 3 3 3 3 3 3 0 3 3 3 12 18 2-tert-butyl-8-ethyl-2-iodoac0tanilide 5 3 2 2 3 3 3 1 1 3 3 3 2 1 3 3 18 13 1 3 1 0 3 3 3 0 1 3 3 3 1 0 3 3 18 8 0. 25 3 0 0 3 1 2 0 0 3 3 3 0 0 0 2 14 3 0. 05 3 0 0 2 2 0 0 0 3 3 3 0 0 0 3 l3 3 2-bromo-2-tert-butyl-6"isopropylacetaniliden 5 3 0 0 3 2 3 0 0 3 3 3 0 0 2 3 17 5 1 3 0 0 3 3 3 0 0 3 3 3 0 0 0 3 18 3 3 0. 25 3 0 0 1 0 3 0 0 3 3 0 0 0 0 3 13 0 0.07 2 1 0 0 0 3 0 0 3 I 3 3 0 1 2 1 10 6 2-chl0r0-2-(1,l-dimethylbutyl)-6-methylacet- 5 3 3 1 3 3 3 2 3 3 3 3 3 1 3 3 18 16 nnilide. 1 3 2 1 3 3 3 3 3 3 3 3 1 1 2 3 18 14 0. 25 3 1 0 1 3 3 0 3 3 3 3 0 0 0 3 16 0 2-bromo-2-tert-butyl-6-ethylacetanilide 5 3 1 2 3 3 3 1 0' 3 3 3 0 1 2 3 18 9 1 3 2 1 3 3 3 2 2 3 3 3 0 2 3 3 18 13 0.25 3 0 0 3 3 3 0 0 3 3 3 1 0 0 3 18 4 0. 05 3 0 0 3 3 3 0 0 3 2 2 0 0 0 3 17 2 2tert-buty1-2-chlor0-6-metl10xyacctanilide 5 3 2' 0 3 0 3 1 1 1 3 3 3 0 2 3 3 15 10 1 2 0 0 0 0 3 0 0 3 3 0 0 0 3 12 0 2"tert-butyl-2-iodo-6-methoxyacetanilide 5 3 1 0 3 I 3 3 0 0 3 3 3 0 O 3 3 18 6 1 3 1 0 3 2 3 2 1 3 3 3 1 0 1 3 17 S 0.25 3 0 0 3 1 3 0 0 3 3 3 1 0 0 3 16 4 2-brom0-2-tert-butyl-6-methoxyacetanilide.. 5 3 2 1 3 3 3 2 1 3 3 3 1 0 3 2 18 11 1 3 1 0 3 3 3 1 2 3 3 3 0 0 3 3 l8 9 0. 25 3 1 0 3 3 3 2 1 3 3 3 0 0 2 3 -18 8 0.05 .2 0 0 2.0 2 0 O 3 3 0 0 0 0 1 11 0 2-ter-tbutyl-l-cl1l0ro-6-mothyl-5'nitroacetanilid. 5 3 2 3 3 3 3 0 0 3 3 3 1 0 3 3 18 10 1 3 0 3 3 3 3 0 3 3 1 0 0 0 3 l8 4 2-bromo-2-tort-butyl-5-chloro-6-methylacetanilide. 1 3 0 0 3 3 3 1 0 3 3 2 0 1 l 2 17 5 0. 5 3 1 0 1 2 2 1 1 3 3 3 1 1 1 3 14 8 See footnotes at 0nd of table.

- and .2-bromo-2-tert-butyl-5',6' dimethylacetanilide TABLE IContinne(l Plant 1 31311 1310- Rate, toxic Rating Compound lb./acre Comments A C D E F G H I .I K L M N 0 Grass Broadleaf 2-tert-butyl-2,5-dichloro-fimothylacetanilide.. 1 3 1 1 2 1 3 0 1 3 3 "2 0 0 2 2 3' 14 l .6 0.5 2 1 1 2 0 l 0 1 3 3 1 1 0 2 1 6 0. 25 3 0 0 3 3 3 0 0 3 3 1 0 0 0 3 18 1 2-tert-butyl-2-chloro-5,6-dimethylacetanilide 5 3 3 .2 3 2 3 2 2 3 3' 3 2 1 3 3 3 17 1 3 2 3 3 3 3 1 1 3 3 3 2 0 3 3 18 13 0.25 2 0 1 2 0 2 0 1 3 3 2 1 0 0 1 11 5 2-chloro-5 ,6-dirnethyl-2- (1 ,l-dimethylpropyl) l acetanilide. 5 3 2 3 3 2 3 2 2 3 3 3 1 1 3 3 17 13 1 3 2 3 2 2 3 1 1 3 3 3 1 1 3 3 16 13 0.25 2 0 1 0 0 3 0 0 3 3 1 0 0 1 3 12 3 2-bromo-2-tert-butyl-5,6-dimetl1ylacetanilide 5 3 1 0 3 2 3 2 0 3 3 3 0 0 2 3 17 7 i 1 3 0 0 3 3 3 0 1 3 3 3 0 0 1 3 18 5 0.25 3.1. 0 0 3 3 3 .0 0 3 3, 3 0 0.. 0 3. .18 3. (2 0. 05 3 0 0 0 3 2 0 1 3 3 2 0 o 0 3 14 3 2-tert-butyl-2-iodo-5,6-dimethylacetanilide 5 3 0 0 3 3 2 0 O 3 3 2 0 0 0 3 17 2 1 3 0 0 3 3 3 0 0 3 3 3 0 0 0 3 l8 3 0.25 3 0 0 1 3 2, 0 0 3 3 2 0 0 0 3 15 2 v 0.05 2 0 0 o 3 0 0 0 3 3 1 0 0 0 2 11 1 2 2-chloro-5,fif-dimethyl-W-(1,1-dimethylb11tyl)- aeetanillde, 5 3 2 1 3 3 3 2 3 3 3 3 1 3 3 3 18 16 1 3 1 1 3 3 3 0 0 3 3 3 0 0 1 3 18 5 0.25 3 0 0 3 3 3 0 0 3 3 1 0 0 0 3 18 1 2-bromo-5,6-dimethyl-2-(1,1-dimethylbutyl)- acetanilide. 5 3 1 0 3 3 3 2 1 3 3 3 1 3 0 3 18 10 I 1 3 1 0 3 3 3 1 0 3 3 2 0 1 0 3 1s 4 I 0.25 3 1 0 3 3 3 2 0 3 3 3 0 1 0 3 18 6 2tert-butyl-2,6-dieholoracetanilide 3 2 2 3 2 3 1 2 3 3 3 3 1 3 3 17 15 1 5 2 1 1 3 0 3 0 0 3 3 3 0 1 1 0 12 3 1 2 0 0 1 0 2 0 0 3 3 3 0 0 1 0 9 4 2-tert-butyl-2-chloro-5-methylacetanilide 5 3 1 0 3 2 3 0 2 3 3 3 0 0 1 3 17 6 1 3 0 0 3 1 3 0 0 3 3 0 0 0 0 3 10 0 0.25 2 0 0 3 1 2 0 0 3 3 3 0 0 0 0 12 0 2-br0m0-2-tert-butyl-5'-methylacetanilide 5 2 1 0 2 0 2 0 1 3 3 3 1 0 0 1 11 5 1 Surface application. 2 Incorporated in soil.

The data in Table I illustrate the general phytotoxic activity as well as the selective phytotoxic activity of the a-haloacetanilides of this invention. It will be noted that the a-haloacetanilides demonstrate very outstanding general phytotoxic activity at several rates of application,- including rates as low as one pound per acre and lower. Thus, these a-haloacetanilides are particularly useful in soil sterilization applications. It will also be noted from the data in Table I that unusual grass specificity can be obtained at lower levels of application. Such grass specificity is achieved at extremely low application rates, for example, at rates as low as 0.05 lb. per acre with 2'-tert-butyl-2-chloro-6'-meth'ylacetanilide so that very economical treatment is possible. The .three botanical types or genera of grasses effectively controlled 3 One species missing.

by the u-haloacetanilides of this invention embrace a large number of plants frequently found in vegetable crops. But these a-haloacetanilides are not limited to removing grasses from broadleaf plants, since the selective action is such that certain genera of grasses can be removed from corn, which is also a genusof grass.

EXAMPLE 32 This example illustrates the surprising phytotoxic superiority of compounds of this invention as compared to closely related compounds which do not have the structure of the a-haloacetanilides of this invention. Pre-emergent greenhouse tests were used and the planting of the seeds was accomplished in the same manner as described in Example 31. The data obtained are reported in Table II wherein the identification of seeds and phytotoxic activity index are .as defined above.

acetanilide.

See footnote at end of table.

TABLE II.-COMPARISON 0F PRE-EMERGENCE PHYTOTOXIC ACTIVITY OF VARIOUS a-HALOACETANILIDES Total Phyto- Plant toxic Rating Com ound Comments p. ABCDEFGHIJKLMNOGrassBroad- 1 leaf 2A3 rt-buty1-2-ehloro-W-methylacetanilide 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 18 21 At 5 1b /aer 2-tert-butyl-2-chloro-4-Inetl1ylacetanilide. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 D 0. 4-tert-b11tyl-2-ehloro-2-methylacetanilide. O 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Do. 2-tert-buty1-2-chloro-6-methy1acetanilide 3 3 3 3 3 3 3 v3 3 3 3 3 3 3 3 18 21 At 1 IbJacre. 2-tert-butyl-2-chloroacetanilide 1 0 0 0 0 0 0 0 0 3 0 0 0 0 0 3 0 Do. 2-tert-butyl-2-chloro-6-methylacetanilide. 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 18 21 Do. 2-ch1oro-2,6-dimethylacetanilide 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Do. 2-tert-buty1-2-0111oro-6-methylacetanil1d 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 18 21 At 5 IbJacre. 2-tert-butyl-2ch1oroacetani1ide- 3 1 1 3 3 3 0 2 3 3 2 0 0 2 3 18 13 Do. 2-tert-b11ty1-2-chloropropionanilide 0 0 '0 0 0 0 0 O 0 0 0 0 0 0 0 0 0 At 25 lbJacre. 2-tert-butyl-3-chloropropionanilide.. O 0 0 Q 0 0 0 0 0 0 0 0 0 0 0 0 0 Do. 2-tert-buty1-2-chl0ro-6-methylacetan 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 18 21 At 5 lb./aere. 2-tert-butyl-2-bromo-6-methylacetan1lid 3 3 0. '3 3 3 3 3 3 3 3 1 2 3 3 18 15 Do. 2'-tert-butyl-2-iodo-G nethylacetanilide. '3 3 .3 .3 3 3 3 3 3 3 3 3 3 3 3 18 21 Do. .2!tert-buty1-2-fluoro-6-m'ethylacetanilide 0 0 0 O 0 0 0 O 0 0 0 0 0 0 0 0 0 At 25 IbJacrel 2-tert-butyl-2-chloro-6-methylacetanilide 13 3. 3 .1 2 3 0 1 3 3 3 3 3 3 15 1 13 At 0.3 1b./acre. N -tert-butyl-2-chlor0-2-methylacetanilid 1 0 0 0 0 2 0 0 1 3 3 0 0 0 6 1 3 Do.

N -tert-butyl-2-ch1oro-4'-methylacetanilid 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 O 0 At 0.5 1b./acre. 2-tert-butyl-2,5-d1chloro-6-methylaeetan 3 1 1 2 1 3 0 1 3 3 2 0 0 2 2 14 6 At 1 lb./acre. N -tert-butyl-2,5-rlichlor0-2-methylacetan1lide 1 0 0 0 0 2 1 1 2 2 1 1 0 0 2 8 4 D o. 2'-t rt-butyl-2,4-dichloroacetanilide 0 l 0 0 0 0 0 0 0 0 2 0 0 0 0 0 2 0 At 51b /aer 4'-bromo-2-tert-butyl-2-chl0ro-6-methylacetamhd 1 0 0 0 0 0 0 0 2 2 0 0 0 0 2 6 0 D N-tert-butyl-2,3-dichloro-2-methylacetanilide. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 D0. 2-bromo-2'-tert-butyl-5-chl0ro-6-methylacetamlide. 3, 0 O 3 3 3 1 0 3 3 2 0 1 1 2 17 5 At 1 IbJacre. 2-bromo-N-tert-butyl-2,3-dichloro-2-methyl- 0 0 0 0 O 0 0 0 1 1 0 0 O 0 0 2 0 At 5 lb./acre.

TABLE II-Continuetl Total Phyto- Plant toxic Rating Compound Comments A B C D E F G H I J K L M N Grass Bi'oatd- 2,4-di-bromo-2-tert-butyl-6-methylacetanilide 1 O 0 0 0 1 2 0 2 2 2 0 1 0 2 7 At 1 lb./acre. 2,4'-di-bromeN-methylacetanilide 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Do. 2-bromo-2-tert-butyl-5,6-dimethylacetanilide. 3 0 0 3 3 3 0 1 3 3 3 0 0 1 3 18 5 At 1 1b./ecre. 2-bromo-N-tert-butyl-5',6-dimethylacetanilide 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Do. 2-tert-butyl-2-chlor0-5,6dimethylacetanilide. 3 3 2 3 2 3 2 2 3 3 3 2 1 3 3 17 At 5 lb./acre. 2-tert-butyl-2-chloro-4-methylacetanilide 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Do. 2'-tert-butyl-2,6-dichlor0acetanilide 2 0 0 1 0 2 0 0 3 3 3 0 0 1 0 9 4 At 1 1b./acre. 4-tert-butyl-2,2-dichloroaeetanilide 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 At 1b./acre. N-tert-butyl-2,2-dichloroacetanilide (J 0 0 0 0 0 0 0 1 0 0 0 0 0 0 l 0 At 1 lb./acre. 2-tert-butyl-2,4-dichloroacetanilide 0 0 0 0 0 0 0 U 0 2 0 0 0 0 0 2 0 At 5 lb.lacre. 2-tert-butyl-2,4,5-trichloroacetanili 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 At 25 IbJacre. 2-tert-butyl-2-ch1oro-5-methylacetanilide 3 O 0 3 1 3 0 0 3 3 O 0 0 0 3 16 0 At 1 lb./acre. 2'-tert-butyl-2-cl1loro-4'-methylacetanilide 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 At 5 lbJacre. 2-tertbuty1 chloroacetanilide 1 0 0 0 0 0 0 0 0 3 0 0 0 0 0 3 0 At 1 lbJacre. 4-tert-butyl-2-chloro-2-methylacetanil 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 At 5 lb./acre.

1 One species missing.

EXAMPLE 33 EXAMPLE 34 The post-emergence phytotoxic activity of representative a-haloacetanilides of this invention was determined in greenhouse tests as follows. The a-haloacetanilide to be tested was applied in spray form to 21-day old specimens of the same grasses and broadleaf plants as used in the pro-emergent tests described in Example 31. The same number of seeds of the same plants used in Example 31 were planted in the 9 /2" x 5% x 2%" aluminum pans arranged in the same manner with a soybean seed in diagonal corners as described above. After the plants were 21-days old, each aluminum pan was sprayed with 6 ml. of a 0.5% concentration solution of the candidate chemical, corresponding to a rate of ap proximately 9 lbs. per acre. This herbicidal solution was prepared from 1.5 ml. of a 2% solution of the candidate compound in acetone, 0.2 ml. of a 3:1 cyclohexanone-emulsifying agent mix, and suflicient water to make a volume of 6 ml. The emulsifying agent was a mixture comprising 35 wt. percent butylamine dodecylbenzene sulfonate and 65 wt. percent of a tall oil-ethylene oxide condensate having about 6 moles of ethylene oxide per mole of tall oil. The injuries to the plants were observed after 14 days and are reported in Table III. The postemergent phytotoxic activity index used in this example is based on the average percent injury of each plant species and is defined as follows:

Average percent injury Numelrical Phytotoxlc activity sea e 0 No ghytotoxicity. 1 Slig t phytotoxielty. 2 Moderate phytotoxicity. 3 Severe phytotoxicity. 4 Plants dead.

Compound General General Grass 2-tert-butyl-Z-chloro-6'-methylaeetanilide 2-tert-butyl-2-chl0ro-6ethylacetanilide 2chlor0-2-(1,1-dimethylpropyl) -6-methylacetanilide 2-bromo2'-tert-butyl-6'-methylacetanilide 2-tert-amy1-2-bromo-6-methylacetaullide 2-bromo-2-(1,1-dimethylbutyl) -6-methylacetanilide. 2-chloro-2- ethyl-6'-(1,1,3,3-tetramethyl) acetanilide. 2-br0mo-2,6-dl-tert-butylacetanillde 2 -tert-butyl-2-iodo-6'-methylaeetanilide 2'-tert-butyl-6'-ethyl-2-io doacetanilide 2-chloro-2-(1,1-dirnethylbutyl) -6'-rnethylacetanilide 2-bromo-2'-tert-butyl-fiethylacetanilide 2-brom0-2-tert-butyl-6'-rnethoxyacetanillde. 2-tert-butyl-2-chloro-6-1nethyl-5'- nitroacetanillde Z-bromo-2-tert-butyl-5'-chloro-6-rnethylacetanilide 2-tert-butyl-2-chloro-5',6-dlmethylacetanilide. i'rchloro-5,6-dlmethyl-2(1,I-dimethylpropybacetanilide 2-bromo-2-tert-butyl-5 ,6dimethylacetan1lide 2'-tert-butyl-2-iodo-5,6'-dimethylacetan1lide 2ch1oro-5 ,6-dimethyl-2- (1,1-djmethylbutyl) acetauilido *2-tert-butyl-2,6-dichloroacetanlllde 2'-tert-butyl-2-chloro-5'-methylacetanillde. 2-bron1o-2-tert-butyl-5'-methylacetanillde c CHO o-- o coo 06cc 0 COM Broadleaf Percent by wt. 2' tert butyl 2 chloro 6-methylacetanilide (98.5% pure) 25.180 Xylene 17.452 Cyclohexanone 52.353 Surface active agent A 5.000

Surface active agent A is a nonionicanionic surfactant blend of a long-chain alkylphenol-etliylcne oxide condensate (5-15 moles) and an alkylarylsulfonate available from Antara Chemicals Co. as Antarate 0181.

Peanuts were planted at Clayton, NC. in the spring and treated 29 days later with the emulsifiable concentrate diluted with water to apply the 2-tert-butyl-2-chloro-6'- methylacetanilide at rates of 3, 6 and 9 lbs./ acre. Three 20-ft. long rows were sprayed at each rate with a spray 12-inches wide. The crop was then inspected by three individuals 34 days later and a herbicidal rating obtained by each individual based on a rating of 1 for no control and a rating of 5 for complete control of the weeds growing in the peanut crop. The average phytotoxicities obtained were 2.6, 4.0, and 4.5 at rates or 3, 6 and 9 lbs/acre, respectively. Crab grass 'and goose grass were the main weeds in the peanut crop.

EXAMPLE as In this example, the pre-emergence phytotoxic activity of the a-haloacetanilides of this invention was determined in a field test. For this test, the following liquid concentrate compositions were prepared:

Concentrate composition A having solution temperature 1 Surface active agent A is a non-ionic and ionic blend of surface active agents of a longchain alkylphenol-ethylcne oxide condensate (5-15unoles) and an alkylaryl-sulfonate available from Antnm Chemicals Co. as Auturatc 9181.

2 Surface active agent I.- is a non-ionic surface active agent comprising a fatty acid-ethylene oxide condensate available from Gcigy Chemical Co. as Alrodyne 610-1.

13 Concentrate composition B' having solution temperature of l C. and containing 1 lb./gal. active ingredient Wt. percent 2-tert-butyl-2-chloro-6'methylacetanilide (99% 1 Surface active agent A is a non-ionic and ionic blend of surface active agents of a long-chain alky1phen0l-ethylene oxide condensate (5-15 moles) and an alkylaryl-sulfonate available from Antara Chemicals Co. as Antarate 9181.

2 Surface active agent B is a non-ionic surface active agent comprising a fatty acidethylene oxide condensate available from Geigy Chemical Co. as Alrodyne 6104.

Concentrate composition C having solution temperature of -8 C. and containing 1 lb./ gal. of active ingredient Wt. percent 2-bromo-2'-tert-butyl-6-methylacetanilide 12.85 Xylene 41.08 Cyclohexanone 41.07 Surface active agent A 1 5.0

1 Surface active agent A is a nondonic and ionic blend of surface active agents of a long-chain alkylphenol-ethylene oxide condensate (5-15 moles) and an alkylaryl-sulfonate available from Antara Chemicals Co. as Antarate 9181. Certain crop plants and weed plants (listed in Table IV) were planted in l00-ft. rows one foot apart at Hazelwood, M0. in the spring. The emulsifiable concentrate was applied the day following the planting parallel to the rows at a decreasingly logarithmic rate starting at 6 lbs/acre at one end of the rows and decreasing to 0.015 lbs/acre at the other end of the rows. Water was used as the carrier in applying the concentrate. The plants were inspected approximately 3 weeks and 6 weeks after planting to pin-point the minimum rates at which slight injury and complete kill occurred. The data obtained are reported in Table IV.

effects can be obtained by modifying the method of use of the herbicidal or phytotoxic compositions of this invention. Thus, unusual grass specificity can be achieved at lower levels of application Whereas at higher levels of application a more general phytotoxic effect or soil sterilization takes place. Therefore, an essential part of this invention is the formulation of phytotoxic compositions that permit a uniform predetermined applicationof active ingredient to the soil or plant system to produce the desired effect.

In general, the a-haloacetanilides of this invention are insoluble in water and somewhat soluble in many organic solvents. The active ingredient need not be dissolved in the extending agent but can merely be dispersed or sus pended therein as a suspension or emulsion. Also, the a-haloacetanilides can first be dissolved in a suitable organic solvent and the organic solution of the active ingredient then incorporated in water or an aqueous extending agent to form a heterogenous dispersion. Examples of some suitable organic solvents for use as extending agents include hexane, benzene, toluene, acetone, cyclohexanone, methylethylketone, isopropanol, butanediol, methanol, diacetone alcohol, xylene, dioxane, isopropyl ether, ethylene dichloride, tetrachloroethane, hydrogenated naphthalene, solvent naphtha, petroleum fractions (e.g., those boiling almost entirely under 400 F., at atmospheric pressure and having flask points above about 80 F., particularly kerosene), and the like. Where true solutions are desired, mixtures of organic solvents have been found to be useful, for example 1:1 and 1:2 mixtures of xylene and cyclohexanone.

Solid adjuvants in the form of particulate solids are very useful in the practice of the present invention because of the low solubility properties of the oc-h3l0- acetanilides of this invention. In using this type of adjuvant, the active-ingredient is either adsorbed or dispersed on or in the finely-divided solid material. Preferably the solid materials are not hygroscopic but are materials which render the composition permanently dry 40 and free flowing. Suitable particulate solids include the TABLE IV.-PRE-EMERGENCE FIELD TESTS Concentrate Concentrate Concentrate Composition A Composition B Composition 0 Rate For Rate For Rate For Rate For Rate For Rate For Complete Sl ght Complete Slight Complete Slight K n ury, Kill, Injury, Kill, Injury, 1b./acre lb./aero lbJacre 1b./aere lb./aere lb./acre 0 72 0. 14 0. 23 0. 05 4. 8 0. 56 1 26 0.15 1. 14 0. 29 6 3. 83 4 0. 29 1. 78 0. 26 6 1. 39 2. 1 0. 05 0. 98 0. 1 1. O 0. 16 0. 16 0. 09 1. 17 0.4 4. 2 0. 63 3. 95 0. 28 5. 0 1. 0 Johnson Grass 0. 76 0. 14 0. 76 0. 1 1. 25 0. 20 Barnyard Grass. 0.35 O. 05 0. 19 0. 03 1. 72 0. 22 Crabgrass 0. 57 0. 03 0. 09 0. 02 l. 20 0. 14 Brome 0. 29 0. 07 0. 16 0. 06 1. 35 0. 10

EXAMPLE 36 natural clays, such as china clays, the bentomtes and the 2-tert-butyl-2chloro-6'-methylacetanilide, applied as Concentrate Composition A of Example 35 at 5 1b./acre in surface application and soil incorporation tests, was found to demonstrate 95.3% control and 99.2% control, respectively, of nut grass, i.e., Cyperus rotundus and Cyperus esculentus. The composition was applied to the soil the day after planting of the seeds and observations made 15 days later by observers of 4 test plots.

As demonstrated in the examples above, quite different 75 attapulgites; other minerals in natural state, such as talc, pyrophyllite, quartz, diatomaceous earth, fullers earth, chalk, rock phosphate, kaolin, kieselguhr, volcanic ash, salt, and sulfur; the chemically modified minerals, such as acid-washed bentonite, precipitated calcium phosphate, precipitated calcium carbonate, calcined magnesia, and colloidal silica; and other solid materials such as powdered cork, powdered wood and powdered pecan or walnut shells. These materials are used in finely-divided form,

15 at least in a size range of 20-40 mesh and preferably in much finer size.

The surface active agent, that is the wetting, emulsifying, or dispersion agent, used in the phytotoxic compositions of this invention to serve in providing uniform dispersions of all formulation components in both liquid and particulate solid form can be anionic, cationic, nonionic, or mixtures thereof. Suitable surface active agents are the organic surface active agents capable of lowering the surface tension of water and include the conventional soaps, such as the water-soluble salts of long-chain carboxylic acids; the amino soaps, such as the amine salts of long-chain carboxylic acids; the sulfonated animal, vegetable, and mineral oils; quaternary salts of high molecular weight acids; rosin soaps, such as salts of abietic acid; sulfuric acid salts of high molecular weight organic compounds; algin soaps; ethylene oxide condensated with fatty acids, alkyl phenols and mercaptans; and other simple and polymeric compositions having both hydrophilic and hydrophobic functions.

The liquid phytotoxic compositions of this invention generally comprise 0.01% to 99% by weight of the active ingredient with the remainder being phytotoxic adjuvant which can be liquid extending agent or surface active agent (including adhesive agent), but preferably is an admixture thereof. Normally it is preferred that the phytotoxic adjuvant be the major component in the composition, i.e. be present in the composition in excess of 50% by weight. Preferably, the surface active agent comprises from 0.1% to 15% by weight of the total composition. The remainder of the composition is the liquid extending agent.

The concentration of active ingredient in the particulate solid or dust compositions of this invention can vary over wideranges depending upon the nature of the solid adjuvant and the intended use of the composition. Since the active ingredients of this invention have very high toxicities and are applied at very low rates in order to obtain selectivity, the concentration of the active ingreclient in the dust composition can be very low and may comprise as little as 1% or less by weight of the total dust composition. By contrast, when the dust composition is to be used for soil sterilization, it may be desirable to have a very high concentration of active ingredient and for such use the active ingredient can comprise as much as to 98% by weight of the total composition. The remainder of the composition is the phytotoxic adjuvant which is usually only the particulate solid extending agent. Normally it is preferred that the solid phytotoxic adjuvant be the major component in the composition, i.e. be present in the composition in excess of 50% by weight. Thus, the surface active agent is not usually required in dust compositions although it can be used if desired. However, if the particulate solid compositions are to be applied as a wettable powder, a surface active agent must be added. Ordinarily the amount of surface active agent is from about 0.01% to about 15% by Weight of the phytotoxic composition.

The phytotoxic compositions of this invention can also contain other additaments, for example fertilizers, pesticides and the like used as adjuvant or in combination with any of the above-described adjuvants. Phytotoxicants useful in combination with the above-described compounds include, for example, 2,4-dichlorophenoxyacetic acids, 2,4,S-trichlorophenoxyacetic acid, 2-methyl-4- chlorophenoxyacetic acid and the salts, esters and amides thereof; triazine derivatives, such as 2,4-bis(3-methoxypropylamino)-6-methylthio-S-triazine, 2-chloro-4-ethylamino-G-isopropylamino-S-triazine and 2-ethylamino-4- isopropylamino-6-methylmercapto-S-tri'azine, and. urea derivatives, such as 3 -(3,4'dichlorophenyl)-l,1-dimethyl urea and 3-(pchlorophenyl)-1,1-dimethyl urea. Fertilizers useful in combination with the active ingredients include, for example, ammonium nitrate, urea and superphosphate. Other useful additaments include materials in which plant organisms take root and grow such as compost, manure, humus, sand and the like.

The phytotoxic compositions of this invention are applied to the plants in the conventional manner. Thus, the dust and liquid compositions can be applied to the plants by the use of power-dusters, broom and hand sprayers and spray-dusters. The compositions can also be applied from airplanes-as a dust or a spray because they are effective in a very low dosage. In order to modify or control growth of germinating seeds or emerging seedlings, the dust and liquid compositions are applied to the soil according to conventional methods and are preferably distributed in the soil to a depth of at least /2 inch below the soil surface. It is not absolutely necessary that the phytotoxic compositions be admixed with the soil particles and these compositions can be applied merely by spraying or sprinkling the surface of the soil. The phytotoxic compositions of this invention can also be applied by addition to irrigation water supplied to the field to be treated. This method of application permits the penetration of the compositions into the soil as the water is absorbed therein. Dust compositions sprinkled on the surface of the soil can be distributed below the surface of the soil by conventional means such as discing, dragging or mixing operations.

The application of an effective amount of active ingredient to the plant is essential in the practice of the present invention. The exact dosage to be applied is dependent not only upon the specific a-haloacetanilide but also upon the particular plant species to be controlled and the stage of growth thereof as well as the part of the plant to be contacted with the toxicant. In non-selective foliage treatments, the phytotoxic compositions of this invention are usually applied at a rate sufiicient to obtain from 5 to 50 lbs. of u-haloacetanilide per acre but lower or higher rates can be applied in some cases. In non-selective pre-emergence treatments, the phytotoxic compositions are usually applied at a somewhat lower rate than in foliage treatments but at a rate which is ordinarily within the same general range, that is at a rate in the range of l to 25 lbs. per acre. However, because of the unusually high unit activity possessed by the active ingredients of this invention, soil sterilization is ordinarily accomplished at a rate of application in the range of l to 10 lbs. per acre. In selective pre-emergence applications to the soil, a dosage of from 0.005 to 5 lbs. of active ingredient per acre is usually employed but lower or higher rates may be necessaryin some instances. It is believed that one skilled in the art can readily determine from the disclosure, including the examples, the optimum rate to be applied in any particular case.

The terms soil and growth media are employed in the present specification and claims in their broadest sense to be inclusive of all conventional soils as defined in Websters New International Dictionary, Second Edition, Unabridged (1961). Thus the terms refer to any substance or media in which vegetation may take root and grow, and are intended to include not only earth but compost, manure, muck, humus, sand and the like, adapted to support plant growth.

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

1. Phytotoxic composition comprising an adjuvant and a herbicidal effective amount of a u-haloacetanilide of the formula 0 IIIHiiCHzX 17.. wherein R is tertiary alkyl of at least 4 and not more than 10 carbon atoms, R is'selected'fro'rnthe group consisting of hydrogen, halogen, primary, secondary and tertiary alkyl of not more than 8'carbon atoms'and alkoxyof not more than 4 carbon atoms, R is selected from the group consisting of hydrogen, primary and secondary alkyl" of not more than 6 carbon atoms, chloride and nitro, andX is selected from the group consisting of chloride; bromide and iodide, provided that one and not more than one of R and R is always hydrogen unless R is primary alkyl or secondary alkyl in which case R is as defined above and further provided that R is primary alkyl or secondary alkyl when R is chloride ornitro.

2. Phytotoxic compositions of. claim 1 wherein R is tertiary alkylof at least 4 and not more than 5 carbon atoms, R is halogen, R is hydrogen and X is 01.

3. Phytotoxic composition of claim 1 wherein R is tertiary alkyl of at least 4 and not more than 5 carbon atoms, R is H, R is primary alkyl'ofnot more than 6 carbon atoms and X is Cl. v I

4. Phytotoxic composition of claim 1 wherein R is tertiary alkyl of at least 4 and not more than 5 carbon atoms, R is primary alkyl, R is primary alkyl and X is Cl.

5. Phytotoxic composition of claim 1 wherein the m-haloacetanilide is 2-tert-butyl-2-chloro6'-methyl-5'- nitroacetanilide.

6. Phytotoxic composition of claim 1 wherein the othaloacetanili-de is 2-bromo-2'-tert-butyl 5' chloro-6'- anethylacetanilide.

7. Phytotoxic composition of claim 1 wherein the d.- haloacetanilide is 2'-tert-butyl-2,5'-dichloro-6'-methylacetanilide.

8. Phytotoxic composition of claim 1 wherein the ahaloacetanilide is 2'-tert-butyl-2-chloro-5',6'-dimethylacetanilide.

9. Phytotoxic composition of claim 1 wherein the haloacetanilide is 2-chloro ,6 dimethyl-2'-(1,l-dimethyl-propyl)acetanilide.

10. Phytotoxic composition of claim 1 wherein the ahaloacetanilide is 2-bromo2'-tert-butyl-5',6'-dimethylacetanilide.

11. Phytotoxic composition of claim 1 wherein the ochaloacetanilide is 2'-tert-butyl-2-iodo-5',6'-dimethyl-acetanilide.

12. Phytotoxic composition of claim 1 wherein the uhaloacetanilide is 2-chloro 5',6' dimethyl-2'-(l,1-dimethyl-butyl acetanilide.

13. Phytotoxic composition of claim 1 wherein the othaloacetanilide is 2-bromo-5',6-dimethyl 2' (1,1-dimethylbutyl)acetanilide.

14. Phytotoxic composition of claim 1 wherein the ahaloacetanilide is 2-br0mo-2'-tert-butyl-6'-methoxyacetanilide.

15. Phytotoxic composition of claim 1 wherein the u-haloacetanilide is 2'-tert-butyl-2i-chloro- 6-methylacetanilide.

16. Phytotoxic composition of claim 1 wherein the ct-haloacetanilide is 2-bromo-2'-tert-butyl-6-rnethylacetanilide.

17. Phytotoxic composition of claim 1 wherein the a-haloacetanilide is 2'-tert-a'myl-2-bromo-6'-methylacetanilide.

18. Phytotoxic composition of claim 1 wherein the ahaloacetanilide is 2-tert-butyl-2-iodo-6 '-methylacetanilide.

19. Phytotoxic composition of claim 1 wherein the a-haloacetanilide is 2'-tert-butyl-2,6'-dichloroacetanilide.

20. Phytotoxic composition of claim 1 wherein the ochaloacetanilide is 2'-tert-butyl-2-chloro-5'-methylacetanilide.

21. Phytotoxic composition of claim 1 wherein the a-haloacetanilide is 2-bromo-2'-tert-butyl-5'-methylacetanilide.

22. Method which comprises exposing plants to a herbicidal amount-oi an a-haloacetanilide of the formula I v IIIH CHzX wherein R is tertiary alkyl of at least 4 and not more than 10 carbon atoms, R? is selectedfrom the group consisting of hydrogen, halogen, primary, secondary and tertiary alkyl of not more than 8 carbon atoms and alkoxy of not more than 4 carbon atoms, R is selected from the group consisting of hydrogen, primary and secondary allcyl of not more than 6 carbon atoms, chloride and nitro, and X is selected from the group consisting. of chloride, bromide andiodide, provided that one and not more than one of R and R? is always hydrogen unless R is primary alkylor'secondary alkyl in whichcase R is as defined above andfurther provided that R is primary alkyl or secondary alkyl when R is chloride or nitro.

23. Composition of claim 1 wherein the adjuvant is a particulate solid.

24. Composition of claim 1 wherein the adjuvant is a liquid.

25. Composition of claim 1 wherein the adjuvant is a surface active agent.

26. Method of claim 22 wherein R is tertiary butyl, R is halogen, R is hydrogen and X is chlorine.

27. Method of claim 22 wherein R is tertiary butyl, R is hydrogen, R is primary alkyl of not more than 6 carbon atoms and X is chlorine.

28. Method of claim 22 wherein R is tertiary butyl, R is primary alkyl, R is primary alkyl and X is chlorine.

29. Method of claim 22 wherein the plants are exposed pre-emergently by application of the alpha haloacetanilide to the soil.

30. Method of claim 22 wherein the plants are exposed post-emergently by application of the alpha-haloacetanilide to the plants.

31. Method which comprises exposing plants to a selectively effective herbicidal amount of an alpha-haloacetanilide of the formula wherein R is tertiary alkyl of at least 4 and not more than 10 carbon atoms, R is selected from the group consisting of hydrogen, halogen, primary, secondary and tertiary alkyl of not more than 8 carbon atoms and alkoxy of not more than 4 carbon atoms, R is selected from the group consisting of hydrogen, primary and secondary alkyl of not more than 6 carbon atoms, chlorine and nitro, and X is selected from the group consisting of chlorine, bromine, and iodine, provided that one and not more than one of R and R is always hydrogen unless R is primary alkyl or secondary alkyl in which case R is as defined above and further provided that R is primary alkyl or secondary alkyl when R is chlorine or nitro.

32. Method of claim 31 wherein the plants are exposed pre-emergently by application of the alpha-haloacetanilide to the soil.

33. Method of claim 31 wherein the plants are exposed post-emergently by applicationof the alpha-haloacetanilide to the plant.

34. Method of claim 22 wherein the a-haloacetanilide is 2'-tert-butyl-2-chloro-6 -methyl-5-nitroacetanilide.

35. Method of claim 22 wherein the a-haloacetanilide is 2-br0mo-2'-tert-butyl-5-chloro-6'-methylacetanilide.

\ 36. Method of claim 22 wherein the ot-haloacetanilide is 2'-tert-butyl-2,5'-dichloro-6 -methylacetanilide.

37. Method of claim 22 wherein the u-haloacetanilide is 2'-tert-butyl-2-chloro-5,6'-dimethylacetanilide.

38. Method of claim 22 wherein the m-haloacetanilide is 2-chloro 5 ',6-dimethyl-2-(1,1-dimethylpropyl) acetanilide.

39. Method of claim 22 wherein the a-haloacetanilide is 2-bromo-2'-tert-butyl-5,6-dimethylacetanilide. v

40. Method of claim 22 wherein the a-haloacetanilide is 2'-tert-butyl-2-iodo-5',6'-dimethylacetanilide.

41. Method of claim 22 wherein the a-haloacetanilide is 2 chloro-5 ,6'-dirnethy1-2'-( 1,1-dimethylbutyl) acetamilide.

' 42; Method of claim 22 wherein the a-haloacetanilide is 2-bromo-5,6"-dimethyl-2'-(1,1-dimethylbutyl) acetani lide.

43. Method of claim 22 wherein the a-haloacetanilide is 2-br0m0-2-tert-butyl-6-methoxyacetanilide.

44. Method of claim 22 wherein the a-haloacetanilide is 2-tert-butyl-2-chloro-6-methylacetanilide.

45. Method of claim 22 wherein the a-haloacetanilide is 2-bromo-2-tert-butyl-6'-methylacetanilide.

46. Method of claim 22 wherein the ot-haloacetanilide is 2'-tert-amyl-2-br0m0-6 '-methyl'acetanilide.

47. Method of claim 22 wherein the u-haloacetanilide is 2-tert-butyl-2-iodo-6'-methylacetanilide.

48. Method of claim 22. wherein the ot-haloacetanilide is 2-tert-butyl-2,6-dichloroacetanilide.

49. Method of claim 22 wherein the a-haloacetanilide is 2'-tert-butyl-2-chloro-5'-methylacetanilide.

50. Method of claim 22 wherein the a-haloacetanilide is 2-bromo-2'-tert-butyl-5'-methylacetanilide.

References Cited U ITED STATES PATENTS FOREIGN PATENTS 139,051 2/1953 Sweden.

JAMES O. THOMAS, IR., Primary Examiner.