JPH021832B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention is based on the general formula [In the formula, A represents groups a and b

[expression] and

[Formula] (wherein R ³ represents halogen, m represents 1 or 2, B represents -CH= or nitrogen), and R ¹ represents a group d

The present invention relates to an oxime ester compound represented by the formula: (wherein R ⁶ and R ⁷ represent lower alkyl, and n represents 1 or 2). The present invention also relates to processes for making compounds of the formula, pre- and post-emergence herbicidal compositions, processes for making such compositions and their use, and also the use of such herbicides themselves. The method for producing a compound of the formula is the general formula A compound of ^{the general} formula It consists of reacting with compounds of the formula in which A has the meaning indicated above or their alkali metal salts, if necessary in the presence of a base. The term "lower alkyl", unless specified otherwise, refers to straight-chain as well as branched-chain hydrocarbon radicals having from 1 to 6 carbon atoms, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert. .--Includes butyl, etc. 1-3 carbon atoms
Preferred are alkyl groups having . The term "halogen" means fluorine, chlorine, bromine and iodine, with chlorine and iodine being preferred. Preferred compounds of the formula are those in which A represents the group b. Furthermore, preference is given to those compounds in which R ⁶ and R ⁷ represent an alkyl group having 1 or 2 carbon atoms, especially a methyl group. The symbol Z as the group to be removed (the formula includes especially chlorine, bromine, iodine, mesyloxy and tosyloxy, and also reactive hydroxy groups, especially triphenylphosphine and azodicarboxylic acids or their esters, especially diethylazodicarboxylate) [For example, the Journal of the Chemical Society of Japan (Bull.
Chem.Soc.Japan) 46, 2833 (1973) or Angewante. Hemy (Angew.Chem.) 88, 111
(1976)]. Because of the asymmetric carbon atom between oxygen and the group -COR ¹ in the compounds of the formula, these compounds can exist as racemates or in the form of optical isomers. The D-form of compounds of formula is preferred in view of its particular active characteristics. Preferred specific compounds are: [(isopropylideneamino)oxy]methyl 2
-[p-[(6-fluoro-2-quinolyl)oxy]phenoxy]propionate, and [(isopropylideneamino)oxy]methyl 2
-[p-[(6-chloro-2-quinoxalinyl)
Oxy]phenoxy]propionates, especially the D-isomers of these compounds. The process of the invention for the preparation of compounds of formula
A compound of the formula is reacted with a compound of the formula or an alkali metal salt thereof in a manner known per se, if necessary in the presence of a base. The reaction is carried out in an inert organic solvent such as a hydrocarbon (e.g. benzene or toluene), an ether (e.g.
(diethyl ether, tetrahydrofuran or dimethoxyethane) or hexamethylphosphoric triamide, etc. Temperature and pressure are not critical and the reaction is carried out from -20° to the reflux temperature of the reaction mixture, preferably from -10 to 30°C.
It is suitably carried out at temperatures between . As mentioned above, the compound of the general formula has an asymmetric carbon atom at the α-position and therefore can exist as optical isomers. The ester component may further contain asymmetric carbon atoms. If desired, the racemate can be separated into dextrorotatory and levorotatory compounds according to known methods. Such methods are used, for example, in industrial and engineering chemistry.
Chemistry) 60 , (8), 12-28.
All isomers and racemic mixtures have herbicidal activity, but the degree of this activity varies. The activity is greatest in the case of the D-isomer, followed by the racemic mixture and then the L-isomer. Isomers, especially D-isomers, can also be prepared synthetically from the corresponding optically active starting materials. The following formula

As a result of the nitrogen-carbon double bond in the radical of the formula, in each case (when R ⁶ and R ⁷ have different meanings) two geometric isomers, called the syn-form and the anti-form is obtained. In some cases it is possible to isolate such isomers. These isomers are also objects of the present invention. The invention also relates to herbicidal compositions containing as active ingredient one or more compounds of the formula defined above. The herbicidal composition conveniently contains at least one of the following substances: a carrier material, a wetting agent, an inert diluent and a solvent. Compounds of the formula are useful in cereals such as barley, oats and wheat, and in rice, cotton, soybeans, sugar beets and weeds in vegetable farms, especially slender foxtail (Alopecurus myosuroides).
myosuroides] and millet types such as cock's foot (Echinochloa crus-galli, great foxtail millet)
It is particularly suitable for controlling the weeds foxtail millet (Setaria faverii) and hair-like millet (Panicum capillare). The compounds of the formula are particularly suitable for controlling weeds in sugar radish farms without causing damage to the farm. Typically,
A concentration of 0.1 to 6 Kg/ha, preferably 0.6 to 2.0 Kg/ha and particularly preferably 1 to 1.5 Kg/ha is sufficient to lead to the desired herbicidal effect with a compound of formula. The compounds according to the invention are particularly active against Alopecruz.

【table】

【table】

Table The above tests were carried out with a 1% solution of the active ingredient in a 1:1 mixture of acetone/water.

Table 1 Compounds of formula are generally insoluble in water and can be formulated according to any method conventional for insoluble compounds. When desired, the compound of formula can be dissolved in a water-immiscible solvent, such as a high-boiling hydrocarbon, conveniently containing a dissolved emulsifier so that it acts as a self-emulsifying oil upon addition to water. The compounds of the formula can also be mixed with a wetting agent in the presence or absence of an inert diluent to form a wettable powder that is soluble or dispersible in water, or they can be mixed with a wetting agent in the presence or absence of an inert diluent. can be used to form solid or powder formulations. Inert diluents with which compounds of formula can be formulated include:
A solid inert medium containing powder or finely divided solid substances such as clay, sand, talc, mica, fertilizers, etc.; such formulations are used as dust or products with larger particle size. exists in any of the following forms. Wetting agents include anionic wetting agents such as soap,
fatty sulfate esters such as sodium dodecyl sulfate, sodium octadecyl sulfate and sodium cetyl sulfate, fatty-aromatic sulfonates such as alkylbenzene sulfonates or butylnaphthalene sulfonates, more complex fatty sulfonates such as the amide condensation products of oleic acid and N-methyl-taurine or It can be the sodium sulfonate of dioctyl succinate. Wetting agents or non-ionic wetting agents, such as condensation products of fatty acids, fatty alcohols or fatty substituted phenols with ethylene oxide, fatty acid esters or ethers of sugars or polyhydric alcohols, obtained from the latter by condensation with ethylene oxide. It may be a product known as a block copolymer of ethylene oxide and propylene oxide. The wetting agent can also be a cationic wetting agent, such as cetyltrimethylammonium bromide. Herbicidal compositions can also be formulated as aerosols, where co-solvents and wetting agents are used in addition to the propellant gas, suitably a polyhalogenated alkane (eg dichlorodifluoromethane). The herbicidal compositions provided by this invention may contain, in addition to the compounds of formula, synergists and other active insecticides, fungicides, herbicides and fungicides. The compounds of the formula can be used in different amounts in their different applications. The herbicidal compositions provided by the present invention may be formulated in a form suitable for storage and transportation. Such forms may contain, for example, from 2 to 90% of one or more compounds of formula. These forms can then be diluted with the same carrier or another carrier to provide the appropriate concentration for practical use. In a ready-for-use composition, then
Active ingredient concentrations of 2 to 80% (weight percent) may be present. However, the active ingredient concentration also
It can be in smaller amounts or in larger amounts. Depending on the purpose of use, active ingredient concentrations of 2-80% or 50-80% are particularly preferred. The following examples illustrate the invention: Example 1 [(isopropylideneamino)oxy]methyl L
1.75 g of (-)-lactate, 2.65 g of triphenylphosphine and 2.72 g of p-[(6-chloro-2-quinoxalinyl)oxy]phenol are dissolved in 10 ml of anhydrous tetrahydrofuran at 0°C. Add 1.75 g of diethyl azodicarboxylate to the resulting solution.
is added dropwise while cooling and stirring. The mixture is then stirred for 0.5 h, poured into 100 ml of water and extracted twice with ethyl acetate. The organic layer is washed with dilute hydrochloric acid and water, dried over sodium sulfate and evaporated. The residue was transferred onto 20 times its volume of silica gel with hexane/ethyl acetate 8:2 as elution solvent.
Chromatography using The eluted product is recrystallized from methylene chloride/n-hexane. Thus, [(isopropylideneamino)
Oxy]methyl D-2-[p-[(6-chloro-
2-quinoxalinyl)oxy]phenoxy]propionate is obtained; [α] ²⁰ _D +20.05° (C = 1.93%, in CHCl ₃ ), melting point 75
~77℃. Similarly, p-[(6-fluoro-2-quinoxalyl)oxy]phenol and p-[(7
-fluoro-2-quinoxalinyl)oxy]phenol from a 1:1 mixture of [(isopropylideneamino)oxy]methyl D-2-[p-[(6-
Fluoro-2-quinoxalinyl)oxy]phenoxy]propionate and [(isopropylideneamino)oxy]methyl D-2-[p-[(7
A 1:1 mixture of -fluoro-2-quinoxalinyl)oxy]phenoxy]propionate is obtained; [α] ²² _D +21.18° (C=1.14% in CHCl ₃ ). The following compound was further obtained by the above method. 2-[(isopropylideneamino)oxy]ether D-2-[p-[(6-chloro-2-quinoxalinyl)oxy]phenoxy]propionate, mp62-64℃, [α] ²⁰ _D = +29.3゜( _CHCl3 ,C
=0.10%); [(isopropylideneamino)oxy]methyl D-2-[p-[[5-(trifluoromethyl)
-2-pyridyl]oxy]phenoxy]propionate, [α] ²² _D = +21.79° (C = 1.59%, CHCl ₃
2-[(isopropylideneamino)oxy]ethyl D-2-[p-[(7-bromo-2-quinolyl)oxy]phenoxy]propionate, [α]
²⁰ _D = +23.5° (C = 1.8%, in CHCl ₃ ), mp74-74.5
°C; 2-[(isopropylideneamino)oxy]ethyl D-2-[p-[[5-(trifluoromethyl)-2-pyridyl]oxy]phenoxy]propionate. Formulation Example A An emulsifiable concentrate is prepared by mixing the following ingredients with each other: 500 g of a compound of formula condensation product of alkylphenol and ethylene oxide; 100 g of calcium dodecylbenzenesulfonate with an oxirane oxygen content of approximately 6% Epoxidized soybean oil 25g Butylated hydroxytoluene 10g Make the mixture 1 with xylene.

Claims (1)

[Claims] 1. General formula [In the formula, A represents groups a and b [Formula] and [Formula] (wherein, R ³ represents a halogen, and m is 1 or 2
, B represents -CH= or nitrogen), and R ¹ represents a group d [Formula] (wherein R ⁶ and R ⁷ represent lower alkyl, and n represents 1 or 2); oxime ester compound of 2. Compounds according to claim 1, in which R ⁶ and R ⁷ represent an alkyl group having 1 or 2 carbon atoms, in particular methyl. 3. A compound according to claim 1 or 2 which is the D-isomer. 4. The compound of claim 1 which is 4[(isopropylideneamino)oxy]methyl 2-[p-[(6-fluoro-2-quinolyl)oxy]phenoxy]propionate. 5 [(isopropylideneamino)oxy]methyl 2-[p-[(6-chloro-2-quinoxalinyl)
The compound of claim 1 which is oxy]phenoxy]propionate. 6. A compound according to any one of claims 4 or 5 which is the D-isomer. 7 General formula [In the formula, A is a group a and b [Formula] and [Formula] (In the formula, R ³ represents a halogen, m is 1 or 2
, B represents -CH= or nitrogen), and R ¹ represents a group d [Formula] (wherein R ⁶ and R ⁷ represent lower alkyl, and n represents 1 or 2); A herbicidal composition comprising a compound of [showing]] and an inert carrier substance. 8 Compound [(isopropylideneamino)oxy]methyl 2-[p-[(6-fluoro-2-quinolyl)oxy]phenoxy]propionate,
[(isopropylideneamino)oxy]methyl 2-
The herbicidal composition of claim 7 selected from [p-[(6-chloro-2-quinoxalinyl)oxy]phenoxy]propionate and the D-isomer of these compounds. 9 General formula [In the formula, A is a group a and b [Formula] and [Formula] (In the formula, R ³ represents a halogen, m is 1 or 2
, B represents -CH= or nitrogen), and R ¹ represents a group d [Formula] (wherein R ⁶ and R ⁷ represent lower alkyl, and n represents 1 or 2); In the method for producing a compound of the general formula [In the formula, Z represents a leaving group, and R ⁶ and
R ⁷ has the meaning given above] with the general formula A process characterized in that it is reacted with a compound of the formula in which A has the meaning indicated above or an alkali metal salt thereof, if necessary in the presence of a base. 10. The process according to claim 9, wherein a compound of the formula 10 Z represents chlorine, bromine, iodine, mesyloxy or tosyloxy is used. 11. The process of any one of claims 9 or 10, wherein the D-isomer is used as a starting material in the formula or the D-isomer is isolated from the resulting racemate. Claims 9 and 10, in which A represents the group b, are used as starting materials of formula 12.
or the method of any one of paragraph 11. 13 R ⁶ and R ⁷ are 1 carbon atom as starting materials
13. The process according to claim 9, wherein a compound of the formula exhibiting an alkyl group having or two alkyl groups, in particular methyl, is used.