GB2072183A - Herbicidal 2-Haloacetanilides - Google Patents

Abstract

Hydrocarbyl or hydrocarbyloxyalkyl-2- haloacetanilide compounds, herbicidal compositions containing said compounds as the active ingredient and herbicidal method of use in various crops, particularly transplant rice. The herbicides herein are particularly effective against annual and perennial weeds commonly associated with rice.

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, particularly for use in transplant rice.

Description of the Prior Art The invention compounds are characterized as 2-chloroacetanilides having specific combination of an n-butoxy radical in one ortho position, an ethyl radical in the other position, and as a substituent on the anilide nitrogen ring a radical selected from the group consisting of allyl, chloroallyl, propargyl, 2- methoxyprop-2-yl or a radical of the formula -CH2OR1 wherein R1 is a C15 alkyl radical.

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/or on the anilide ring including alkyl, alkenyl, alkynyl, alkoxy, polyalkoxy, alkoxyalkyl, heterocyclyl, halogen, etc., radicals. The most relevant compounds of the prior art in this area appear to be those disclosed in the following references: U.S. Patent Numbers 3,268,584, 3,442,945, 3,547,620, 3,773,492,4,152,137 and Belgian Patent No.810,763. However, none of those prior art references disclose any data for compounds of the type disclosed herein as being useful transplant rice herbicides, nor do they disclose or suggest the particular species of this invention.

The 2-haloacetanilides of the prior art which are known to have utility as transplant rice herbicides differ significantly in structure from those disclosed herein. Specifically, said prior art herbicides all contain lower alkyl radicals in both ortho positions to the anilide nitrogen atom and an alkoxyalkyl radical on said nitrogen atom. Accordingly, those prior art rice herbicides are non-related and non-suggestive of those disclosed herein. However, in order to provide a basis for comparison, the relative herbicidal efficacy of compounds according to this invention is compared with that of Machete9 herbicide (registered trademark of Monsanto Company), the active ingredient of which is 2',6t-diethyl-N-(n-butoxymethyl)-2-chloroacetanilide (common name "butachlor").Butachlor and a homolog thereof ("ethyl butachlor" herein) are disclosed as rice herbicides in U.S. Patent Number 3,663,200. Of the known prior art of 2-haloacetanilide herbicides, only Machete herbicide has achieved commercial status to date.

While prior art rice herbicides have been found useful, there is a continuing need for improved rice herbicides which control resistant weeds of economical significance at lower rates of application, maintain control or suppression of such weeds for longer periods of time, while maintaining safety to the rice crop and improved toxicity with respect to fish and mammals.

The above prior art herbicides have been found to share one or more undesirabre properties as transplant rice herbicides. Among certain disadvantages of prior art transplant rice herbicides are their generally weak performance in the control and/or suppression of the economically-significant resistant perennial weeds Cyperus serotinus, Eleocharis kuroguwai and Sagittaria trifolia together with diminishing efficacy in the control or suppression of the annual weeds Echinochloa crus-galli and, to a lesser extent, Monochoria vaginalis, within a period from 2-6 weeks. These performance weaknesses are particularly apparent at lower rates of application, i.e. down to 0.17 Ib/A (0.19 kg/ha) and lower.In fact, field tests have shown that in some treatments some of the prior art herbicides failed to selectively control Eleocharis kuroguwai at rates below 5.36 Ib/A (6 kg/ha) or even 2.67 Ib/A (3 kg/ha) for periods as short as 2 or 3 weeks. Similarly, in field tests, it was also found that some prior art rice herbicides failed to provide any meaningful suppression of Sagittaria trifolia after four or five weeks.

It is, therefore, an object of this invention to provide a class of herbicides which is particularly useful in transplant rice.

A further object of this invention is the provision of selected herbicides which: (1) are safe (i.e., produce no more than about 15% injury) on transplant rice at rates up to at least 2.0 Ib/A (2.24 kg/ha); (2) selectively control Echinochloa crus-galli, Monochoria vaginalis, Cyperus serotinus and Eleocharis kuroguwai, and (3) provide increased suppression of Sagittaria trifolia.

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 reiates to herbicidally active compounds, herbicidal compositions containing these compounds as active ingredients and herbicidal method of use of said compositions in various crops, particularly transplant rice.

It has now been found that a selective group of 2-haloacetanilides characterized by specific combinations of radicals on the anilide nitrogen atom, a specific alkoxy radical in one ortho position and an ethyl radical in the other ortho position possess unexpectedly superior and outstanding selective herbicidal properties as transplant rice herbicides vis-a-vis prior art herbicides of related structure of the most relevant prior art, including a commercial rice herbicide.

A primary feature of the herbicidal compositions of this invention is their ability to control and/or suppress annual and perennial narrowleaf weeds in transplant rice, particularly the prevalent and economically-significant annuals such as Echinochloa crus-galli, Monochoria vaginalis and resistant perennial species such as Cyperus serotinus, Eleocharis kuroguwai and Sagittaria trifolia and other noxious weeds.

The compounds of this invention are characterized by the formula

wherein R is allyl, chloroallyl, propargyl, 1 -methoxy-prop-2-yl or a radical of the formula --CHOR,, where R, is allyl or a C15 alkyl, preferably C,, alkyl radical.

Preferred species of this inventior. are those where in the above formula R is propargyl, 1 - methoxyprop-2-yl and species wherein R1 is allyl, n-propyl, sec-butyl, 2-methylbutyl or isoamyl. Other species of this invention are those where R in the above formula is allyl, chloroallyl or -CH20R1 groups wherein R1 is methyl, isopropyl n-butyl or isobutyl.

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 an N-alkylation of the anion of the appropriate secondary 2haloacetaniiide with an alkylating agent under basic conditions.

Example 1 below illustrates the use of said N-alkylation to prepare one species of this invention.

A modified N-alkylation process is described in Example 2 for preparing another species of the invention. The modified N-alkylation process described in Example 2 herein involves the in-situ preparation of halomethyl alkyl or alkenyl ethers used as starting materials in the N-alkylation process.

Example 1 2'-n-butoxy-6'-ethyl-2-chloroacetanilide, 5.4 g (0.02 mol), propargyl bromide, 2.6 g (0.022 mol) and 2.0 g of benzyl triethylammonium chloride were mixed in 1 50 ml of methylene chloride and chilled. To the mixture at 1 50C was added 45 ml of 50% NaOH all at once and stirred for 5 minutes, then 1 50 ml of cold water was added. The layers were separated, washed with water, then dried over MgSO4 and evaporated by Kugelrohr to obtain 4.45 g (73% yield) of yellow oil, b.p. 11 80C at 0.03 mm Hg.

Anal. Calc'd for C1,CINO3 (%): C, 66.33; H, 7.20; Cl, 11.52; Found: C, 66.35; H, 7.21; Cl, 11.50.

The product was identified as N-propargyl-2'-n-butoxy-6'-ethyl-2-chloroacetanilide.

Example 2 Following substantially the same procedure described in Example 1, but substituting allyl bromide as the alkylating agent, 4.9 g (79% yield) of yellow oil boiling at 1 280C (at 0.05 mm Hg Kugelrohr) was obtained.

Anal. Calc'd for C1tH24ClNO2 (%): C, 65.90; H, 7.81; Cl, 11.44; Found: C, 65.89; H, 7.81; Cl, 11.42.

The product was identified as N-allyl-2-n-butoxy-6'-ethyl-2-chloroacetanilide.

Example 3 This example describes a modification of the N-alkylation process described in Example 1. In this process embodiment, the alkylating agent is formed in-situ, thus effecting a more efficient, economic and simple operation.

To a chilled mixture of 6.96 g (0.12 mol) of allyl alcohol, 1.8 g (0.12 mol) of anhydrous paraformaldehyde and 1 50 ml of methylene chloride was added 4.71 g (0.06 mol) of acetyl chloride; the mixture was stirred for 90 minutes until all the paraformaldehyde was dissolved. To the mixture was then added 5.4 g (0.02 mol) of 2'-n-butoxy-6'-ethyl-2-chloroacetanilide, 2.0 g of benzyl triethylammonium chloride and 50 ml of methylene chloride. The mixture was cooled to 1 000C and 50 ml of 50% NaOH added all at once and stirred for 15 minutes. The layers were separated, washed with water, dried over Mg SO4 and evaporated by Kugelrohr to obtain 6.0 g (92% yield) of clear oil, b.p.

1220C at 0.04 mm Hg.

Anal. Calc'd for C18H26CINO3 (%): C, 63.61; H, 7.71; CI, 10.43; Found: C, 63.60 H, 7.74; Cl, 10.42; The product was identified as N-(allyloxymethyl)-2'-n-butoxy-6'-ethyl-2-chloroacetanilide.

Example 4 Following substantially the same procedure described in Example 3, but substituting 2-butanol as the alkylating agent, 4.15 g (78% yield) of clear oil was obtained, b.p. 11 80C at 0.02 mm Hg (Kugelrohr).

Anal. Calc'd for C19H30ClN03 (%): C, 64.12; H, 8.50; CI, 9.96; Found: C, 64.05; H, 8.52; CI, 9.90.

The product was identified as N-(sec-butoxymethyl)-2'-n-butoxy-6'-ethyl-2-chloroacetanilide.

The secondary anilide starting material used in the above examples is prepared according to known methods, e.g., by haloacetylation of the corresponding primary amine with such haloacetylation agents as a haloacetyl halide or anhydride. Typically, the appropriate quantity of the appropriate primary amine is dissolved in a solvent such as methylene chloride containing a base, e.g.,-10% NaOH, and stirred vigorously while mixing with a solution of the haloacetyl halide, e.g., chloroacetyl chloride, under external cooling, e.g., at 1 5-250C. The layers are separated and the organic solvent layer washed with water, dried and evaporated in vacuo.

The primary amines used to prepare the secondary anilides also may be prepared by known means, e.g., by catalytic reduction of the corresponding appropriately-substituted nitrobenzene, e.g., 2- alkoxy-6-alkyl nitrobenzene, in a solvent such as an alcohol, e.g., ethanol, using platinum oxide catalyst.

Example 5 This example describes the preparation of N-(2-methoxyprop-2-yl)-2'-n-butoxy-6'-ethyl-2- chioroacetanilide.

To a chilled solution of N-(2-methoxyprop-2-yI)-2'-n-butoxy-6'-ethylaniline, 4.42 g (0.016 mol), in 0.0176 mol of 10% NaOH and 100 ml CH2Cl2was added 2 g (0.0176 mol) of chloroacetyl chloride dropwise; the solution was stirred for 10 minutes, the formed layers separated and the organic phase washed with water, dried over MgSO4 and evaporated by Kugelrohr to obtain 3.5 g (65% yield) of a yellow oil, b.p. 1 320C at 0.07 mm Hg.

Anal. Calc'd for C18H28CINO3 (%): C, 63.24; H, 8.26; CI, 10.37; Found: C, 63.16; H, 8.27; CI, 10.36.

The product was identified as in the lead sentence of this example.

The secondary anilide starting material used in Example 5 is obtained by known means (e.g., as in Belgian Patent 810,763 mentioned above). Thus, 1 9.3 g (0.1 mol) of 2'-n-butoxy-6'-ethylaniline was heated at 500C in 1 5 ml of ethanol and 1 5 ml glacial acetic acid, then 9.68 g (0.11 mol) of methoxyacetone and 0.1 g PtO2 added and the mixture hydrogenated at 500C for 4 hours; the mixture was filtered, evaporated by Kugelrohr at 1 000C 0.07 mm Hg to obtain a yellow oil.

Anal. Calc'dfor C16H27N02(%): C, 72.41; H, 10.25; N, 5.28; Found: C, 72.36; H, 10.27; N, 5.23.

The product was identified as N-( 1 -methoxyprop-2-yl)-2'-n-butoxy-6'-ethylaniíine.

Examples 6-13 Following substantially the same procedure and conditions described in Examples 1-4 using the same secondary anilide but substituting the appropriate alkylating agent as starting material and quantities thereof, the corresponding products in Examples 6-1 3 corresponding to the formula in Table I were prepared. Thus, Examples 6-12 were prepared according to the N-alkylation process described in Examples 3 and 4 and the product of Example 13 was prepared by the N-alkylation process of Examples 1 and 2.

Table I

Analysis Ex. No. R1 BPOC (mmHg) Element Calculated Found 6 i-C5H11 137 (0.04) C 64.94 64.96 H 8.72 8.75 CI 9.58 9.58 7 i-C4Hg 120(0.03) C 64.12 64.06 H 8.50 8.53 Cl 9.96 10.06 8 n-C3H7 117(0.02) C 63.24 63.31 H 8.26 8.27 CI 10.37 10.42 CH3 9 CH2CHCH2CH3 134 134(0.03) C 64.94 64.86 9 8.72 CH H 8.72 8.72 Cl 9.58 9.62 10 n-C4Hg 128 (0.03) C 64.12 64.05 H 8.50 8.49 Cl 9.96 9.91 11 CH3 130(0.04) C 61.24 61.31 H 7.71 7.71 CI 10.30 10.33 12 i-C3H, 119 (0.02) C 63.24 63.41 H 8.26 8.31 Cl 10.37 10.46 Cl 13 -CH2C=CH2 136(0.1) C 59.31 59.47 H 6.73 6.78 CI 20.60 20.52 As noted above, the compounds of this invention have been found to be effective against major Asian weeds as transplant rice herbicides. However, pre-emergence and post-emergence herbicidal activity against other weeds in other crops has also been shown.Tables II and Ill summarize results of tests conducted to determine the pre-emergent herbicidal activity of the compounds of this invention.

The pre-emergent tests were conducted 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. Gn 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 moved into a greenhouse bench where they are watered by subirrigation as needed to give adequate moisture for germination and growth.

Approximately 2 weeks after seeding and treating, the plants were observed and the results recorded. Tables II and III below summarize such results. The herbicidal rating was obtained by means of a fixed scale based on the percent injury of each plant species. The ratings are defined as follows: % Control Rating 0-24 0 25-49 1 50-74 2 75-100 3 Undetermined 5 The plant species utilized in one set of tests, the data for which are shown in Table II are identified by letter in accordance with the following legend:: A Canada Thistle E Lambsquarters I Johnsongrass B Cocklebur F Smartweed J Downy Brome C Velvetleaf G Yellow Nutsedge K Barnyardgrass D Morningglory H Quackgrass Table II Pre-emergent Plant Species Compound of Example No. kg/ha A B C D E F G H I J K 1 11.2 3 2 1 2 3 3 3 3 3 3 3 5.6 3 2 1 2 3 2 3 3 0 3 3 2 11.2 3 2 2 3 3 3 3 3 3 3 3 5.6 2 1 1 1 1 1 3 2 0 3 3 3 11.2 5 0 1 1 2 2 3 3 3 3 3 5.6 5 0 0 0 3 2 2 3 3 3 3 4 11.2 3 0 0 0 2 1 3 2 0 3 3 5.6 3 0 0 0 1 2 2 3 0 3 3 5 11.2 5 0 1 0 3 2 3 3 5 3 3 5.6 5 0 0 0 2 3 1 3 5 3 3 6 11.2 5 0 0 0 0 1 0 3 0 3 3 5.6 5 0 0 0 0 0 3 0 0 3 3 7 11.2 2 0 3 2 3 3 3 3 1 3 3 5.6 3 1 2 3 3 3 2 3 1 3 3 8 11.2 3 0 0 0 2 1 3 2 1 3 3 5.6 3 1 0 0 2 1 3 2 0 3 3 9 11.2 5 0 0 0 0 1 1 2 0 3 3 5.6 5 0 0 0 0 0 0 0 0 3 3 10 11.2 3 0 1 1 1 2 2 3 3 3 3 5.6 1 0 0 0 3 1 1 1 1 3 3 11 11.2 3 1 2 3 3 2 3 3 2 3 3 5.6 0 0 2 2 2 1 3 2 3 3 3 12 11.2 2 0 1 3 3 1 3 3 2 3 3 5.6 1 0 1 1 1 1 3 2 1 3 3 13 11.2 0 0 1 0 2 0 3 2 0 3 3 5.6 0 0 0 0 1 0 0 1 0 3 3 The compounds were further tested by utilizing the above procedure on the following plant species: L Soybean R Hemp sesbania M Sugarbeet E Lambsquarters N Wheat F Smartweed O Rice C Velvetleaf P Sorghum J Downy brome B Cocklebur S Panicum Spp.

Q Wild Buckwheat K Barnyardgrass D Morningglory T Crabgrass The results are summarized in Table III.

Table III Pre-emergent Plant Species Compound of Example No. kg/ha L M N O P B Q D R E F C J S K T 1 5.6 2 3 3 3 3 1 2 3 3 3 3 2 3 3 3 5 1.12 0 2 3 3 3 0 2 0 3 3 2 0 3 3 3 5 0.28 1 2 3 2 2 0 1 0 3 3 3 0 3 3 3 5 0.06 0 0 1 1 0 0 0 0 0 0 0 0 2 1 3 5 0.01 Q 0 0 0 0 1 0 0 0 0 0 0 0 0 2 5 Table Ill (Continued) Pre-emergent Plant Species Compound of Example No. kg/ha L M N O P B Q D R E F C J S K T 2 5.6 0 3 3 3 3 0 2 1 2 3 3 0 3 3 3 5 1.12 0 3 2 3 3 0 1 0 1 3 2 0 3 3 3 5 0.28 0 2 2 3 1 0 0 0 0 1 0 0 3 2 3 5 0.06 0 1 0 1 0 5 0 0 0 0 0 0 1 0 2 5 0.01 0 1 0 0 0 0 0 0 0 0 0 0 0 0 2 5 3 5.6 0 2 3 3 3 0 3 0 1 3 3 1 3 3 3 5 1.12 5 1 2 2 1 0 1 1 0 2 1 0 3 3 3 5 0.08 0 1 1 2 1 0 0 0 0 1 0 0 3 3 3 5 0.56 0 0 0 0 0 0 0 0 0 0 1 0 0 0 3 5.

4 5.6 0 2 3 3 3 0 1 0 2 2 2 0 3 3 3 5 1.12 0 0 1 1 0 0 0 0 1 0 0 0 3 2 3 6 0.28 0 1 0 0 0 0 0 0 0 0 0 0 2 1 3 5 0.06 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 5 0.01 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 5 5 5.6 0 2 3 3 3 0 1 1 2 3 3 1 3 3 3 5 1.12 0 0 2 2 3 0 1 0 0 1 1 0 3 3 3 5 '0.28 0 0 0 1 0 0 0 0 0 0 0 0 2 3 3 5 0.06 0 0 0 0 0 0 0 0 0 0 0 0 1 0 2 5 0.01 0 0 0 0 0 0 0 0 0 0 0 0 1 0 1 5 6 5.6 0 1 2 1 1 0 0 1 0 0 0 0 3 3 3 5 1.12 0 0 0 0 0 0 0 0 0 0 0 0 3 3 3 5 0.28 0 0 0 0 0 0 0 0 0 3 0 0 2 0 3 5 0.06 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 5 7 5.6 1 3 2 3 3 2 2 3 3 3 3 1 3 3 3 3 1.12 0 2 1 2 3 0 1 1 3 3 1 0 3 3 3 3 0.28 0 1 0 1 3 0 1 0 2 0 0 0 3 3 3 3 0.06 0 1 0 0 1 0 1 0 1 0 0 0 1 2 3 3 0.01 0 0 0 0 0 0 1 0 1 0 0 0 0 1 2 1 8 5.6 1 2 3 3 3 0 3 1 2 3 3 0 3 3 3 5 1.1,2 0 0 2 3 2 0 2 0 2 0 1 0 3 3 3 5 0.28 0 0 0 1 1 0 0 0 0 0 0 0 3 3 3 5 0.06 0 0 0 0 0 0 0 0 0 0 0 0 1 0 3 5 0.01 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 5 9 5.6 0 1 1 1 1 0 1 0 1 1 0 0 3 3 3 5 1.12 0 1 0 0 0 0 0 0 2 3 1 1 3 1 3 5 0.28 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 5 0.06 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 5 10 5.6 0 1 2 2 3 0 1 0 1 1 1 0 3 3 3 5 1.12 0 0 1 0 1 0 0 0 3 0 0 0 3 2 3 5 0.28 0 0 0 0 0 0 0 0 0 0 0 0 2 1 3 5 0.06 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 5 11 5.6 0 3 3 3 3 0 1 3 3 3 3 1 3 3 3 5 1.12 0 3 2 3 3 0 1 1 1 2 2 0 3 3 3 5 0.28 0 2 0 2 2 0 1 0 2 2 1 0 3 3 3 5 Table Ill (Continued) Pre-emergent Plant Species Compound of Example No. kg/ha L M N O P B 0 D R E F C J S K T 12 5.6 0 3 3 3 3 0 2 1 2 2 2 0 3 3 3 5 1.12 0 2 2 3 1 0 1 0 1 2 1 0 3 3 3 5 0.28 0 1 0 2 0 0 0 0 0 0 0 0 3 1 3 5 0.06 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 5 0.01 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 5 13 5.6 0 2 3 3 2 0 2 1 2 3 1 0 3 3 3 5 1.12 0 1 2 2 1 0 2 0 2 1 0 0 3 3 3 5 0.28 0 0 1 1 0 0 0 0 1 0 0 0 3 1 3 5 0.06 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 5 0.01 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 5 The herbicides of this invention have been found to possess unexpectedly superior properties as transplant rice herbicides, most particularly in the effective selective control of the economically significant resistant annual weeds, Echinochloa crus-galli and Monochoria vaginalis and the perennials Cyperus serotinus (but for an exception or two) and Eleocharis kuroguwai, while in some instances suppressing the perennial weed Sagittaria trifolia to a greater extent than the commercial herbicide Machete, and also controlling or suppressing many other less-resistant perennial and annual weeds.

In order to illustrate the unexpectedly superior properties of compounds according to this invention both on an absolute basis and on a relative basis, comparative tests were conducted in the greenhouse. In these tests Machete herbicide (the only current commercial 2-haloacetanilide rice herbicide) was tested for comparative purposes.

In the discussion of test data below, occasional reference is made to herbicide application rates symbolized as "GR,5" and "GR8s"; these rates are given in kilograms per hectare (kg/ha) which are convertible into pounds per acre (Ibs/A) by dividing the kg/ha rate by 1.12. GR15 defines the maximum rate of herbicide required to produce 15% or less crop injury, and GR85 defines the minimum rate required to achieve 85% inhibition of weeds. The GR,5 and GR85 rate 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 relative degree of crop safety and weed injury and is expressed in terms of the GR,5/GR85 ratio, i.e., the GR,5 rate for the crop divided by the GR85 rate for the weed, both rates in kg/ha (Ib/A).

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 safety factors, i.e., herbicide 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., the herbicide possesses 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; the higher the numerical value, the greater selectivity of the herbicide for weed control in a given crop.

In one comparative test in the greenhouse, herbicidal activity data were obtained and are presented in Table IV comparing the relative efficacy of the compounds of Examples 1, 3-6, 8 and 9, representative compounds of this invention, with butachior, (active ingredient in Machete, a commercial rice herbicide) as selective herbicides against economically-significant Asian weeds commonly associated with transplant rice.

The test procedure used in this greenhouse test is as follows: Ray silt loam top soil containing about 0.05% by weight of krillium and sifted through a 0.5 in. (0.6 cm) screen and is fumigated about 5-10 days prior to use. Pots are then filled with said Ray silt loam soil to a ievel to allow for a 1 in.

(2.54 cm) flooding depth. Rice plants (Bluebelle) of 2 to 3 weeks age are transplanted to the pots and bulbs or seeds of the test weeds also planted in the pots. The pots are then flooded and the test chemical applied to the surface of the flood water. The flood water is reduced to allow for germination of the Echinochloa crus-galli (barnyardgrass) seed and subsequently reflooded and maintained in that I condition. Observations of percent inhibition using a scale of 0100% are made about 3 weeks after treatment (WAT).

Test data shown in Table IV below represent percent inhibition of the plants within the test rate limits of 0.28 kg/ha to 2.24 kg/ha (0.25-2.0 Ib/A). The data terms are expressed in terms of GR,5 and GR85 rates, respectively, for rice and the weeds, as explained above; selectivity factors are shown in parentheses below each weed: "NS" means non-selective within the test rate limits. The degree of control of Sagittaria trifolia, one of the most important commercial problem weeds and the most 2haloacetamide-resistant perennial of the test weeds, is shown in the last column of Table IV; the percent control shown is at the maximum test rate of 2.24 kg/ha. The weed species are identified as follows: Echinochloa crus-galli (EC), Monochoria vaginal is (MV), Cyperus serotinus (CS), Eleocharis kuroguwai (EK) and Sagittaria trifolia (ST).

Table IV GR,5 Rate RKg/Ha) GR85 Rate (Kg/HaJ ST Control at at 2,24 Kg/Ha Compound Rice EC MV CS EK ST (%) Butachlor 2.24 < 0.28 < 0.25 < 0.25 0.4 > 2.24 15 ( > 8.0) ( > 8.0) ( > 8.0) (5.0) (NS) Ex. 1 2.24 < 0.28 < 0.28 < 0.28 < 0.28 > 2.24 65 ( > 8.0) ( > 8.0) ( > 8.0) ( > 8.0) (NS) Ex. 3 > 2.24 < 0.28 < 0.28 < 0.28 < 0.28 > 2.24 30 ( > 8.0) ( > 8.0) ( > 8.0) ( > 8.0) (NS) Ex. 4 > 2.24 < 0.28 < 0.28 < 0.28 < 0.28 > 2.24 20 ( > 8.0) ( > 8.0) ( > 8.0) ( > 8.0) (NS) Ex. 5 > 2.24 < 0.28 < 0.28 < 0.28 < 0.28 > 2.24 10 ( > 8.0) ( > 8.0) ( > 8.0) ( > 8.0) (NS) Ex. 6 > 2.0 < 0.28 < 0.28 < 0.28 0.43 > 2.24 10 ( > 8.0) ( > 8.0) ( > 8.0) ( > 4.7) (NS) Ex. 8 1.96 < 0.28 < 0.28 < 0.28 < 0.28 > 2.24 70 ( > 7) ( > 7.0) ( > 7.0) ( > 7.0) (NS) Ex. 9 1.87 < 0.28 - < 0.28 0.31 0.86 > 2.24 25 ( > 6.7) ( > 6.7) (5.4) (1.9) (NS) Reference to the data in Table IV will show several important advantages of the invention compounds relative to butachlor as follows: (1) Examples 3-6 had higher rice safety factors; (2) Examples 1, 3-5 and 8 had higher selectivity factors against EK and (3) Examples 1, 3, 4, 8 and 9 all exhibited a higher percentage control of ST than butachior. The overall superiority of compounds according to this invention, particularly those of Examples 1 and 3-6, vis-a-vis the commercial herbicide, is clearly shown by the data in Table IV.

In another comparative test in the greenhouse, other compounds according to this invention were also compared with butachlor as a standard transplant rice herbicide. The compounds of Examples 2, 7 and 10-1 3 and butachlor were tested according to the above-described procedure; the test data are shown in Table V.

Table V GR,5 Rate GR85 Rate rKg/Ha) (Kg/Ha) ST Control --- at 2.24 Kg/Ha Compound Rice EC MV CS EK ST (%) Butachlor 1.68 0.99 1.3 > 2.24 .71 > 2.24 25 (1.7) (1.3) (NS) (2.4) (NS) Ex.2 1.8 < 0.28 < 0.25 0.78 < 0.28 > 2.24 10 ( > 7.2) ( > 7.2) (2.6) ( > 7.2) (NS) Ex. 7 > 2.24 < 0.28 < 0.43 < 0.52 .47 > 2.24 0 ( > 8.0) ( > 5.3) (4.3) (4.8) (NS) Ex. 10 > 2.24 < 0.28 < 0.28 > 2.24 < 0.28 > 2.24 0 ( > 8.0) ( > 8.0) (NS) ( > 8.0) (NS) Ex. 11 1.12 < 0.28 < 0.28 0.95 < 0.28 > 2.24 10 (4.0) ( > 4.0) (1.2) ( > 4.0) (NS) Ex. 12 0.75 < 0.28 < 0.28 1.8 < 0.28 > 2.24 15 ( > 2.7) ( > 2.7) (NS) ( > 2.7) (NS) Ex. 13 1.12 < 0.28 < 0.28 1.0 < 0.28 > 2.24 20 ( > 4.0) ( > 4.0) (1.1) ( > 4.0) (NS) Referring to the test data in Table V, it is again noted that each of the invention compounds exhibited one or more advantages over butachlor as follows: (1) Examples 2, 7 and 10 exhibited higher safety factors in rice and (2) every invention compound exhibited higher selectivity factors against EC, MV, CS (except Example 10) and EK than butachior. Although butachlor exhibited higher safety factors than Examples 11-1 3 and higher percentage control of ST than the invention compounds, these advantages were offset by significantly lower selectivity factors in most of the weeds in the test.It should be mentioned that although greenhouse and field test will vary from test to test (more in the greenhouse than the field usually), the comparative data shown in the tables herein were under identical conditions with respect to all herbicides in the test.

In other comparative tests in the greenhouse, one at a maximum test rate of 1.12 kg/ha and another a maximum test rate of 2.24 kg/ha, the compound of Example 3 and butachlor were tested in Upland seeded rice. It was found that as an average of the two tests, the compound of Example 3 selectively controlled Echinochloa crus-galli (barnyardgrass) at 0.31 kg/ha (0.277 Ib/A) while maintaining rice safety at a rate of > 1.43 kg/ha (1.23 Ib/A), resulting in a selectivity factor of at least 4.6.

In contrast, butachlor (a commercial rice herbicide), required 0.7 kg/ha (0.625 Ib/A) to selectively control the same weed with rice safety maintained at > 1.68 kg/ha ( > 1.5 Ib/A) resulting in a selectivity factor of at least 2.4 i.e., about one-half that of the compound of Example 3.

In further tests in the greenhouse, the compound of Example 3 was tested for its activity against annual weeds in sugarbeets at test rates within the range of 0.07 to 1.12 kg/ha (0.0625 to 1.0 Ib/A).

The GR,5 and GR85 rates for sugarbeets and the various weeds are shown in Table VI; the selectivity factors for the herbicide against the weeds in sugarbeets are shown in parenthesis below the weeds; "NS" means non-selective within the test limits. The following abbreviations are used in the table: barnyardgrass (BYG), wild oats (WO), downy brome (DB), redroot pigweed (RRP), blackgrass (BG), large crabgrass (LCG) and yellow foxtail (YFT).

Table VI GR,5 Rate RKg/ha) GR85 Rate (Kg/ha) Sugarbeets BYG WO DB RRP BG LCG YFT > 1.12 < 0.07 0.28 0.21 > 1.12 0.14 0.14 0.14 ( > 16) ( > 4) ( > 5.3) (NS) ( > 8) ( > 8) ( > 8) The data in Table VI show that the compound of Example 3 selectively controlled every weed in the test, except redroot pigweed, at rates well below 1.12 kg/ha, thus proving the versatility of that compound as an effective herbicide in important crops.

The invention compounds may be safely used with the normal degree of care required for handling herbicidal compounds; no special precautions are required.

Therefore, it will be appreciated from the foregoing detailed description that compounds according to to this invention have demonstrated unexpected and outstandingly superior herbicidal properties both absolutely and relative to structurally-relevant compounds of the prior art, one of which (butachlor) is the active ingredient in a commercial herbicide. More particularly, the compounds of this invention have proven to be outstanding selective herbicides, particularly in the control of economically-significant Asian annual and perennial weeds in transplant rice.In more particular, compounds according to this invention exhibit outstanding control of the annual grasses Echinochioa crus-galli and Monochoria vaginalis and perennials such as Cyperus serotinus, Eleocharis kuroguwai and some members are particularly effective against Sagittaria trifolia, while controlling and/or suppressing other less-resistant annual grasses and perennials, including those mentioned in Tables II, III and VI above, and others.

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 solidus, 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 suitable combination of these.

The compositions of this invention, particularly liquids and wettable powders, preferably contain as a conditioning agent one or more surface-active agents in amounts sufficient to render a given composition readily dispersible in water or in oil. The incorporation of a surface-active agent into the compositions greatly enhances their efficacy. By the term "surface-active agent" it is understood that wetting agents, dispersing agents, suspending agents and emulsifying agents are included therein.

Anionic, cationic and non-ionic agents can be used with equal facility.

Preferred wetting agents are alkyl benzene and alkyl naphthalene sulfonates, sulfated fatty alcohols, amines or acid amides, long chain acid esters of sodium isothionate, esters of sodium sulfosuccinate, sulfated or sulfonated fatty acid esters, petroleum sulfonates, sulfonated vegetable oils, ditertiary acetylenic glycols, polyoxyethylene derivatives of alkylphenols (particularly isooctylphenol and nonylphenol) and polyoxyethylene derivatives of the mono-higher fatty acid esters of hexitol anhydrides (e.g., sorbitan). Preferred dispersants are methyl cellulose, polyvinyl alcohol, sodium lignin sulfonates, polymeric alkyl, naphthalene sulfonates, sodium naphthalene sulfonate, and the polymethylene bisnaphthalene sulfonates.

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 both.

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 emuiqification agent until uniform and then homogenized to give 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 suspension, 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 theaqueous 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 microcapsuies 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 waterimmiscible solvents, together with a surface active agent. Suitable solvents for the active ingredient of this invention include dimethylformide, dimethylsulfoxide, N-methylpyrrolidone, hydrocarbons and water-immiscibel 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 emuisifiable 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 heat 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. Other herbicidal compounds useful in combination with the active ingredients of this invention, particularly for use in tranplant rice, include, for example, methyl-5-(2,4dichlorophenoxy)-2-nitrobenzoate (common name "bifenox", active ingredient in Modown herbicide), 1 -3-Dimethyl-4-(2,4-dichlorobenzoyl)-5-pyrazolyl paratoluene sulfonate (code designation "SW- 751"), cr-(,B-naphthoxy)propionanilide (coded "MT-101"), 2,4-dichloro-3'-methoxy-4'-nitrodiphenyl ether (coded "X-52"), 3,4-dichloropropionanilide (common name "propanil"), etc. For use in other nonrice crops, other herbicidal compounds may also be combined with compounds according to this invention. For example, such other compounds include 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-Ch loro-4-ethylamino-6-isopropyla mino-s-triazine 2-Chloro-4,6-bis(isopropylamino)-s-triazine 2-Chloro-4,6-bis(ethylamino)-s-triazine 3-lsopropyl-1H-2,1 ,3-benzothiadiazin-4-(3H)-one 2,2 dioxide 3-Amino-1 ,2,4-triazole 6,7-Dihydrodipyrido( 1 ,2-a::2', 1 '-c)- pyrazidiinium salt 5-Bromo-3-isopropyl-6-m ethyluracil 1,1 '-Dimethyl-4,4'-bipyridinium 5-tert-butyl-3-(2,4-dichioro-5-isopropoxyphenyl)- 1 ,3,4-oxadiazol-2-one Ureas N'-(4-chlorophenoxy) phenyl-N,N-dimethylurea N,N-di methyl-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 dipropylthiolcarba mate Acetamides/Acetanilides/Anilines/Amides 2-Chloro-N,N-diallylacetamide N,N-dimethyl-2,2-diphenylacetamide N(2,4-dimethyl-5-[[(trifluornmethyl)suIfonyHamino]phenyI)acetamide N-lsopropyl-2-chloroacetanilide 2',6'-Diethyl-N-methoxymethyl-2-chloroacetanilide 2'-Methyl-6'-ethyl-N-(2-methoxyprop-2-yl)-2-chloroacetanilide a,,x,a-Trifluorn-2,6-dinitro-N,N-diprnpyl-p-t6lu idine No(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)phenoxyjpropionate 3-Amino-2,5-dichlorobenzoic acid 2-Methoxy-3,6-dichlorobenzoic acid 2,3,6-Trichlorophenylacetic acid N-1-naphthylphthalamic acid Sodium 5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoate 4,6-Dinitro-o-sec-butylphenol N-(phosphonomethyl) glycine and its C1 monoalkyl amine and alkaline metal salts and combinations thereof Ethers 2,4-Dichlorophenyl-4-nitrop henyl ether 2-Chloro-a -trifluoro-p-tolyl-3-ethoxy-4-nitrodiphenyl ether Miscellaneous 2,6-Dichlorobenzonitrile Monosodium acid methanearsonate Disodium methanearsonate The herbicides of this invention may be used singly, as mixtures with other herbicides and may be used in sequential use with other herbicides.For example, treatments of a transplant rice crop with the herbicides of this invention may be followed with treatments of other herbicides or mixtures such as S4-chlorobenzyl diethyithiocarbamate (common name "benthiocarb") plus 2-chloro-4,6-di(ethylamino)1,3,5-triazine (common name "Simazine") or 3-isopropyl-(1 H)-benzo-2,1 ,3-thiadiazine-4-one-2,2- dioxide (common name "bentazone") or 4-(4-chloro-2-methylphenoxy)butyric acid (common name "MCPB").

The compounds of this invention have their primary utility in transplant rice. However, as indicated by the test data for the compound of Example 3 in Table V, at least some members of this class may also be used in direct-seeded rice. However, because of the high unit activity of compounds according to this invention, direct-seeded rice may be less tolerant of some members of the invention compounds. Accordingly, it is within the purview of this invention to combine these herbicides with safeners or antidotes to enhance the tolerance of both transplanted and direct-seeded rice thereto.

Exemplary safeners contemplated as useful with the herbicides of this invention include the phenylglyoxylonitrile-2-oxime cyanomethyl ether described in U.S. Patent No. 4,152,137, 2,4- disubstituted-5-thiazolecarboxylic acids and derivatives thereof as described in U.S. Patent No.

4,199,506 and other known safeners for 2-haloacetanilides in rice.

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 1 50.0 Phosphate ester of ethoxylated alcohols (e.g. GAFACO RE-610) 4.125 Ethoxylated tertiary amine derived from fatty oils such as palm oil (e.g.) Ethomeen(B) C/1 2) 0.875 Mononchlorobenzene 13.5 Cg aromatic solvent (T-400) 31.5 100.00 B. Compound of Example 3 46.45 GAFAC RE-610 4.125 Ethomeen C/12 0.875 MCB 48.55 100.00 C. Compound of Example No.4 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.5 10.0 Xylene 90.0 100.00 B. Compound of Example No. 6 85.0 Dimethylsulfoxide 15.0 100.00 C. Compound of Example No. 7 50.0 N-methylpyrrolidone 50.0 100.00 Weight Percent D.Compound of Example No. 8 5.0 Ethoxylated castor oil 20.0 Rhodamine B .5 Dimethyl formamide 74.5 100.00 III. Emulsions Weight Percent A. Compound of Example No. 9 40.0 Polyoxyethylene/polyoxypropylene block copolymer with butanol (e.g., Tergitol XH) 4.0 Water 56.0 100.00 B. Compound of Example No. 10 5.0 Polyoxyethylene/polyoxypropylene block copolymer with butanol 3.5 Water 91.5 100.00 IV. Wettable Powders Weight Percent A. Compound of Example No. 1 25.0 Sodium lignosulfonate 3.0 Sodium N-methyl-N-oleyl-taurate 1.0 Amorphous silica (synthetic) 71.0 100.00 B. Compound of Example No. 3 80.0 Sodium dioctyl sulfosuccinate 1.25 Calcium lignosulfonate 2.75 Amorphous silica (synthetic) 16.00 100.00 C. Compound of Example No. 4 10.0 Sodium lignosulfonate 3.0 Sodium N-methyl-N-oleyl-ta urate 1.0 Kaolinite clay 86.0 100.00 V. Dusts Weight Percent A. Compound of Example No. 10 2.0 Attapulgite 98.0 100.00 B. Compound of Example No. 11 60.0 Montmorillonite 40.0 100.00 C. Compound of Example No. 12 30.0 Bentonite 70.0 100.00 D. Compound of Example No. 13 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. 3 30.0 Diatomaceous earth (20/40) 70.0 100.00 C. Compound of Example No. 4 0.5 Bentonite (20/40) 70.0 100.00 D. Compound of Example No. 5 5.0 Pyrophyllite (20/40) 95.0 100.00 VII. Microcapsules A.Compound of Example No. 1 encapsulated in polyurea shell wall 49.2 Sodium lignosulfonate (e.g. Reax 888B) 0.9 Water 49.9 100.00 B. Compound of Example No. 3 encapsulated in polyurea shell wall 10.0 Potassium lignosulfonate (e.g., Reax(3 C-21) .5 Water 89.5 100.00 C. Compound of Example No. 4 encapsulated in polyurea shell wall 80.0 Magnesium salt of lignosulfate (TreaxB 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 use in aqueous or soil media, the plant species and stage of development thereof, the type and condition of soil, the amount of rainfall and the specific anilide 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 suffice or be required in some instance.For example, in some upland-seeded rice tests, compounds according to this invention have shown a measurable amount of injury to barnyardgrass at extremely low rates.

Thus, the compound of Example 3 exhibited 5% control of barnyardgrass at 0.035 kg/ha (0.0313 Ib/A) and the compound of Example 5 exhibited 10% control of barnyardgrass at 0.0175 kg/ha (0.01563 Ib/A). 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 (37)

Claims

1. Compound having the formula

wherein R is allyl, chloroallyl, propargyl, 1 -methoxyprop-2-yI or a hydrocarbyloxymethyl radical of the formula -CH2OR1,wherein R, is allyl or a C15 alkyl radical.

2. Compound according to Claim 1 which is N-propargyl-2'-n-butoxy-6'-ethyl-2chloroacetanilide.

3. Compound according to Claim 1 which is N-(1-methoxyprop-2-yl)-2'-n-butoxy-6'-ethyl-2chloroacetanilide.

4. Compound according to Claim 1 which is N-(a llyloxymethyl)-2'-n-butoxy-6'-ethyl-2- chloroacetanilide.

5. Compound according to Claim 1 wherein R1 is a C35 alkyl radical.

6. Compound according to Claim 5 which is N-(n-propoxymethyl)-2'-n-butoxy-6'-ethyl-2chloroacetanilide.

7. Compound according to Claim 5 which is N-(sec-butoxymethyl)-2'-n-butoxy-6'-ethyl-2chloroacetanilide.

8. Compound according to Claim 5 which is N-(2-methylbutyl)-2'-n-butoxy-6'-ethyl-2chloroacetanilide.

9. Compound according to Claim 5 which is N-(isoamyloxymethyl)-2'-n-butoxy-6'-ethyl-2chloroacetanilide.

10. Compound according to claim 5 which is N-(isobutoxymethyl)-2'-n-butoxy-6'-ethyl-2chloroacetanilide.

11. Compound according to Claim 5 which is N-(n-butoxymethyl)-2'-n-butoxy-6'-ethyl-2chloroacetanilide.

12. Herbicidal compositions comprising an adjuvant and a herbicidally effective amount of a compound of the formula

wherein R is allyl, chloroallyl, propargyl, 1 -methoxyprop- 2-yl or a hydrocarbyloxymethyl radical of the formula-CH2OR1, wherein R1 is ally or a C,, alkyl radical.

13. Composition according to Claim 12 wherein said compound is N-propargyl-2'-n-butoxy^6'- ethyl-2-chloroacetanilide.

14. Composition according to Claim 12 wherein said compound is N-(1-methoxyprop-2-yl)-2'-nbutoxy-6'-ethyl-2-chloroacetanilide.

1 5. Composition according to Claim 12 wherein said compound is N-(allyloxymethyl)-2'-nbutoxy-6'-ethyl-2-chloroacetani lide.

1 6. Composition according to Claim 12 wherein in said compound R1 is a C35 alkyl radical.

1 7. Composition according to Claim 16 wherein said compound is N-(n-propoxymethyl)-2'-nbutoxy-6'-ethyl-2-chloroacetanilide.

18. Composition according to Claim 16 wherein said compound is N-(sec-butoxymethyl)-2'-nbutoxy-6'-ethyl-2-chloroacetanilide.

19. Composition according to Claim 1 6 wherein said compound is N-(2-methylbutyl)-2'-n butoxy-6'-ethyl-2-chloroacetanilide.

20. Composition according to Claim 1 6 wherein said compound is N-(isoamyloxymethyl)-2'-nbutoxy-6'-ethyl-2-chloroacetanilide.

21. Composition according to Claim 16 wherein said compound is N-(isobutoxymethyl)-2'-n butoxy-6'-ethyl-2-chloroacetanilide.

22. Composition according to Claim 16 wherein said compound is N-(n-butoxymethyl)-2'-nbutoxy-6'-ethyl-2-chloroacetanilide.

23. Method for combatting undesirable plants in crops which comprise applying to the locus of said plants a herbicidally effective amount of a compound of the formula

wherein R is allyl, chloroallyl, propargyl, 1 -methoxyprop-2-yl or a hydrocarbyloxymethyl radical of the formula -CH20R1, wherein R1 is allyl or a C15 alkyl radical.

24. Method according to Claim 23 wherein said crop is transplanted rice.

25. Method according to Claim 24 wherein said compound is N-propargyl-2'-n-butoxy-6'-ethyl2-chloroacetanilide.

26. Method according to Claim 24 wherein said compound is N-(1-methoxyprop-2-yl)-2'-n butoxy-6'-ethyl-2-chloroacetanilide.

27. Method according to Claim 2-; wherein said compound is N-(allyloxymethyl)-2'-n-butoxy-6'ethyl-2-chloroacetanilide.

28. Method according to Claim 24 wherein in said compound R, is a C35 alkyl radical.

29. Method according to Claim 28 wherein said compound is N-(n-propoxymethyl)-2'-n-butoxy6'-ethyl-2-chloroacetanilide.

30. Method according to Claim 28 wherein said compound is N-(sec-butoxymethyl)-2'-n-butoxy6'-ethyl-2-chloroacetanilide.

31. Method according to Claim 28 wherein said compound is N-(2-methylbutyl)-2'-n-butoxy-6'ethyl-2-chloroacetanilide.

32. Method according to Claim 28 wherein said compound is N-(isoamyloxymethyl)-2'-n-butoxy6'-ethyl-2-chloroacetanilide.

33. Method according to Claim 28 wherein said compound is N-(isobutoxymethyl)-2'-n-butoxy6'-ethyl-2-chloroacetanilide.

34. Method according to Claim 28 wherein said compound is N-(n-butoxymethyl)-2'-n-butoxy6'-ethyl-2-chloroacetanilide.

35. Method for combatting weeds in transplant rice which comprises applying to the locus thereof a herbicidally effective amount of N-(a I lyloxymethyl)-2'-n-butoxy-6'-ethyl-2-chloroacetanilide.

36. Method for combatting weeds in transplant rice which comprises applying to the locus thereof a herbicidally effective amount of N-propargyl-2'-n-butoxy-6'-ethyl-2-chloroacetanilide.

37. Method for combatting weeds in transplant rice which comprises applying to the locus thereof a herbicidally effective amount of N-( 1 -methoxyprop-2-yl)-2'-n-butoxy-6'-ethyl-2-chloroacetanilide).