DE2405833A1 - N-(1-Alkanoyloxy-2-halo-ethyl)-ureas - prepd e.g. by reacting ureas with haloacetaldehydes and esterifying the products - Google Patents

Abstract

Ureas of formula (I): (where R is 1-12C alkyl, 3-8C cycloalkyl, phenyl substd. by is not >2 F, Cl or Br atoms or CF3, NO2, lower alkyl or lower alkoxy residues, or phenylthio, phenoxy or phenylsulphonyl substd. by is not >2 F or Cl atoms; R1 is H or 1-4C alkyl; R2 is 1-4C alkyl; Z is Cl or Br; Y is H or Z; and R3 is H or 1-6C alkyl), e.g. 1-methyl-1-(1-formyloxy-2,2,2-trichloroethyl)-3-(3,4-dichlorophen- yl)-urea, are new cpds. They may be prepd. by reacting cpds. of the formula RR1N-CO-NH-R2 (II) with aldehydes for the formula O=CH-CZ2Y (III), treating the resulting cpd. of the formula RR1N-CO-NR2-CHOH-CZ2Y (IV) with SOCl2, and reacting the resulting cpd. of the formula RR1N-CO-NR2-CHCl-CZ2Y (V) with an ammonium salt of the formula NH4. OCOR3 (I; R3=H) may also be obtained by reacting (V) with formic acid in the presence of an acid acceptor. (I) are pre- and post-emergence herbicides active against both grassy and broadleaved weeds. Some of the cpds. (I) are selective.

Description

1-Alkanoyloxyhalogenäthylureas and herbicides containing the same Agents The invention relates to 1-alkanoyloxyhalogenoethyl ureas and the same containing herbicidal agents.

Chattaway et al, Proc. Roy. Soc. (London) A-134, pp. 372-84 (1931) and Chattaway at al, J. Chem. Soc. 1933, 30 describe compounds produced by condensation of chloral with aryl ureas and acetylation of the resulting condensation products with acetic anhydride to form diacetylureas and / or bisureido ethers were manufactured.

U.S. Patent 3,040,082 and Hoover et al., J.Org.Chem. 28 (7), 1825-30 (1953) describe β-polyhalo-α-hydrocarbyl isocyanates and their derivatives, such as 1- (1-hydroxy-2,2,2-trifluoroethylene) -3-phenylurea and 1- (1-hydroxy-2,2,2-trichloroethyl) -3-phenylurea and their use as Herbicides.

U.S. Patents 2,846,399, 2,902,356, 3,418,334 and 3,488 also describe 376 Urea and its uses.

The invention relates to 1-AlkanoyloxyhalogenEthylureas of the general formula (I) wherein R is an alkyl radical with 1 to 12 carbon atoms, a cycloalkyl radical with 3 to 8 carbon atoms, a phenyl radical which is substituted with up to 2Xpluor, chlorine or bromine atoms or trifluoromethyl, nitro, lower alkyl or lower alkyloxyreske or a Phenylthio, phenoxy or phenylsulfonyl radical which is substituted by up to 2 fluorine or chlorine atoms; R1 is a hydrogen atom or an alkyl radical having 1 to 4 carbon atoms; R2 is an alkyl radical with 1 to 4 carbon atoms; Z is a chlorine or bromine atom; Y denotes a hydrogen atom or Z and R3 denotes a hydrogen atom or an alkyl group with 1 to 6 carbon atoms. Preferably, R denotes an alkyl group with 1 to 6 carbon atoms, a cycloalkyl group with 5 to 6 carbon atoms or a phenyl group with 1 to 2 fluorine, chlorine or bromine atoms or trifluoromethyl, nitro, lower alkoxy or lower alkyl radicals. It is even more preferred if R is a phenyl radical which is substituted by 1 to 2 fluorine or chlorine atoms. A single trifluoromethyl radical or a small fluorine atom is preferably linked to the phenyl radical in the ortho position.

Y is preferably a chlorine or bromine atom and R1 is a hydrogen atom and R2 is an alkyl radical having 1 to 4 carbon atoms.

x) (0 to 2) A compound is particularly preferred where R2 is the methyl radical and R3 is a hydrogen atom.

The examples for R include / methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, decyl, dodecyl, cyclopropyl, cyclobutyl, Cyclopentyl, cyclohexyl, phenyl, 2-fluorophenyl, 2-chlorophenyl, 2-chloro-4-bromophenyl, 3-methylphenyl-, 4-methoxyphenyl-, 2-nitrophenyl-, 2-trifluoromethylphenyl-, 4-phenoxyphenyl-, 4-phenylthiophenyl, 4-phenylsulfonylphenyl and 4- (2-chlorophenoxy) phenyl radical.

Examples of R1, R² and R3 include the hydrogen atom, the Methyl, ethyl, n-propyl, isopropyl, butyl or hexyl radical.

The compounds according to the invention include: 1-methyl-1- (1-formyloxy-2,2,2-trichloroethyl) -3- (4-phenoxyphenylthurea, 1-methyl-1- (1-formyloxy-2,2,2-trichloro-thyl) -3- (4- / T'-chlorophenoxy7phenyl) urea, 1-ethyl-1- (1-formyloxy-2,2,2-tribromomethyl) -3- (4-phenylsulfonylphenyl) urea, 1-methyl-1- (1-formyioxy-2,2,2-trichloroethyl3-3-phenylurea, 1-ethyl-1- (1-formyloxy-2,2,2-trichloroEthyl) -3- (2-trifluoromethylphenyl) urea, 1-methyl-1- (1-formyloxy-2,2,2-tribromoethyl) -3- (2-fluorophenyT) -urea, l-butyl-l- (l-formyloxy-2,2-dichloro-2- bromogthyl3-3- (2-nitrophenyl ) urea, 1-methyl-1- (1-formyloxy-2,2-dichloroethyl) -3- (4-methylphenyl) urea, 1-butyl-1- (1-formyloxy-2,2,2-tr-.fluorethyl) -3- (4-methoxyphenyl) urea, 1-methyl-1- (1-formyloxy-2,2,2-trichloroethyl) -3-methylurea, 1-methyl-1- (1-formyloxy-2,2a2-triehloroethyl) -3-dodecylurea, 1-methyl-1 (1-formyloxy-2,2,2-trichlorosthyl) -3-cyciopentylurea, 1-methyl-1- (1-propionyloxy-2,2,2-trichloroethyl) -3-cyclohexylurea, 1-methyl-1- (1-formyloxy-2,2,2-trichloroethyl) -3- (4-phenylthiophenyl) urea, 1-methyl-1- (1-formyloxy-2,2,2-trichloroethyl) -3 - (2-bromophenyl ) urea, 1-methyl-1- (1-acetoxy-2,2,2-tribromoEthyl) -3- (2-chlorophenyl) urea, 1-methyl-1- (1-acetoxy-2,2,2-trichloroethyl) -3- (4-nitrophenyl) -urea, 1-methyl-1- (1-acetoxy-2-bromo-2,2-dichloroethyl ) -3- (3-chloro-4-methoxyphenyl) urea, 1-methyl-1- (1-propionyloxy-2,2,2-trichloroethyl) -3- (2-fluorophenyl) urea, 1-methyl-1- (1-butyryloxy-2-bromo-2,2-dichloroethyl) -3- (3-chlorophenyl) urea, 1-methyl-1- (1-pentanoyloxy-2,2-dichloroethyl) -3- (2,4-dichlorophenyl) urea, 1-methyl-1- (1-n-hexanoyloxy-2,2,2-trichloroethyl) -3- (2-nitrophenyl) urea and 1-ethyl-1- (1-acetoxy-2,2,2-trichloroethyl) -3- (2-methyl-4-chlorophenyl) urea.

The preferred compounds according to the invention are those in which R, R1 and R2 are as defined above and R3 is a hydrogen atom and Y and Z are chlorine atoms. The preparation of the compound x of the present invention begins with the w-hydroxy compounds represented by the formula (IV). Such compounds are produced by reacting a urea with an aldehyde according to the following reaction equation (1): wherein R, R1, R2, Y and Z have the above meanings.

The carbon reactants (II) used for reaction (1) are compounds known in the art. The aldehyde (III) can be a compound such as chloral (trichloroacetaldehyde), dichloroacetaldehyde, dichlorobromoacetaldehyde or Be tribromoacetaldehyde. The reaction (1) can be carried out in the presence of a solvent or can be carried out without a solvent. Generally stoichiometric close to urea and aldehyde used. A small amount of acid, preferably Sulfuric acid or perchloric acid can be used. The reaction temperature lies between 20 and 100 ° C. In general, the reaction is very quick and is completely finished after a few minutes. Response times from 30 seconds to 10 hours are considered sufficient.

The α-hydroxy compound (1V) is then converted to the α-chlorine compound of the formula (V) by mixing the α-hydroxy compound (IV) either in purified form or in the reaction mixture of reaction (1) with thionyl chloride according to the following reaction equation (2 ) implements: wherein R, R1> R2, -Y and Z have the above meanings.

The reaction (2) can be carried out using a molar amount of thionyl chloride up to an excess of 20 mol, based on the urea, can be carried out. The reaction temperature is 20 to 1000 ° C. and the reaction time is 1 to 20 hours. If necessary, reactions (1) and (2) can be used to prepare the α-chlorine compound (V) by simply mixing the urea reactant (II), the aldehyde reactant (III) and the thionyl chloride are combined. The α-chlorine product (V) can through Slurry in a solvent such as diethyl ether or methylene chloride, collect the product on a filter and purifying by recrystallization from inert Solvents such as a 1: 1 mixture of 1,2-dimethoxymetban and methylene chloride or a 1: 1 mixture of acetone and methylene chloride.

The compounds according to the invention are prepared by reacting the α-chloro compound (V) with ammonium formate or alkanoate, as shown in the following reaction equation (3): wherein, R1, R2, R3, Z and Y are as defined above.

The above reaction (3) can be easily carried out by mixing the Reactants, preferably in a solvent such as 1,2-dimethoxyethane, in an amount of 2 to 50% by volume for about 0.25 to 20 hours at one temperature from about 20 to 100 ° C. The solvent is then removed and that Product isolated and by customary methods such as extraction, filtration, recrystallization etc., cleaned. Generally the ammonium formate or alkanoate is in excess in an amount of from 5 to 100% of the alpha-chlorourea reactant (V).

The formyloxy-substituted ureas of the formulas (I), (II) or (III) can also be prepared by reacting the α-chlorinating bond (V) with formic acid in the presence of an acid acceptor according to the following reaction equation (4): wherein R, R1, R2, Z and Y have the above meanings and B is an acid acceptor.

The above reaction (4) can be easily brought into contact of α-chlorourea (V) with an excess of formic acid up to 20 mol, based on the urea (V), at a temperature of 0 to 500C.

Suitable acid acceptors are organic nitrogen bases, which are not have free N-H groups, such as trialkylamines, e.g.

Trimethylamine and triethylamine, and pyridine compounds, e.g.

Pyridine and 2-methylpyridine. The molar ratios of acid acceptor to urea (V) are essentially equimolar, e.g. 1.5: 1 to 1: 1.5. The α-formyloxy product (VII) is isolated and 'by customary methods, such as filtration, extraction or Crystallization purified.

The following examples serve to further illustrate the invention.

Example 1 Preparation of 1-methyl-1- (1-formyloxy-2,2,2-trichloroethyl) -3- (3,4-dichlorophenyl) urea 2 g (0.02 mol) of triethylamine were slowly added to a slurry of 4.4 g (0.02 mol) 1-methyl-1- (1,2,2,2-tetrachloroethyl) -3- (3,4-dichlorophenyl) urea in 50 ml of formic acid. added. After stirring for 15 minutes, a precipitate of triethylamine hydrochloride formed. The reaction mixture was then poured into 300 ml of water, filtered and dried. The resulting crude product had a melting point of 136 to 145 ° C. That Crude product was then diluted with 15 to 20 ml of benzene and filtered. The filtrate was concentrated to about 10 to 15 ml and diluted with 50 ml of hexane, the product as a white solid with a melting point of 138 to 1400 ° C.

Analysis: -Calculated: C 33.5%, H 2.3%, N 7.1%, Found C 33.8%, H 2.1 8, N 7.1%.

Example 2 Preparation of 1-methyl-1- (1-formyloxy-2,2,2-trichloroethyl) -3- (2-fluorophenyl) urea Following the procedure of Example 1 but using of the corresponding fluorophenyl derivative of urea as a starting compound the title compound obtained as a product. Melting point: 124-127 ° C.

Analysis for halogen: Calculated: 38.4% Found: 38.8% the In general terms, ureas according to the invention are both pre-emergence as also post-emergence herbicides. For pre-emergence control of unwanted vegetation the ureas according to the invention in herbicidal amounts on the environment, for example the soil interspersed with seeds and / or seedlings of such vegetation, upset.

Such an application inhibits the growth or kills the seeds, the germinating seeds or seedlings. In post-emergence applications, the Urea applied directly to the foliage or other parts of the plant. In general they are effective on weed grasses as well as broad-leaved weeds. Some of the ureas according to the invention can in relation to the type of application and / or be selective for the type of weed.

It was pre and 'na'chauflau herbicide tests using representative ureas according to the invention carried out according to the following methods: Pre-emergence test An acetone solution of the test urea was made by mixing 750 mg of urea, 220 mg of a nonionic surfactant and 25 ml of acetone. To this solution was added about 125 ml of water containing 156 mg of surfactant contained.

Seeds of the test vegetation were placed in a pot with soil, and the urea solution was applied uniformly at a dose of 100 pg per cm2 to the Sprayed the surface of the earth.

The pot was watered and placed in a greenhouse. From time at time the pot was watered and placed on the casserole of the seedlings for three weeks, observed their health etc. After this period the herbicidal became effectiveness of urea is evaluated based on the physiological observations. Here a scale from 0 to 100 was used; 0 meant no phytotoxicity, 100 meant uil constant killing.

Post-emergence test The test urea was tested in the same way as described above for the pre-emergence test. The concentration of the Urea in this formulation was 5,000 ppm. This formulation became uniform on two equal pots with -24-day-old plants (about 15 to 25 plants per Pot) at a dose of 100 po per cm2. When the plants were dry they were placed in a greenhouse and then from time to time as needed poured down. The plants were periodically tested for phytotoxic effects as well as physiological and morphological responses to treatment are observed. After three weeks the herbicidal effectiveness of urea was evaluated based on these observations. A scale from 0 to 100 was used; 0 meant no phytotoxicity, 100 meant complete killing.

The results of these tests are shown in the table. T a b e l l e Herbicidal effect compound pre-emergence / post-emergence O W C M P L 1-methyl-1- (1-formyloxy-2,2, - 60/65 95/90 100/100 100/100 100/100 100/100 trichloroethyl) -3- (3,4-dichlorophenyl) urea 1-methyl-1- (1-formyloxy-2,2,2-100/60 100/30 100/0 100/65 100/90 100/75 trichloroethyl) -3- (2-fluorophenyl) urea O = wild oats (avena fatua) W = chicken millet (Echinochloa crusgalli) C = blood millet (Digitaria sanginallis) M = wild mustard (Brassica arvensis) P = bow amaranth (Amaranthus retroflexus) L = white goosefoot (Chenopodium album) The amount The amount of urea administered will vary depending on the particular part or plant of the plant Plant growth medium with which it is intended to be brought into contact, the general one Application area, i. protected areas, such as greenhouses, in contrast to outdoor areas, such as fields, as well as the desired type of control. In the pre-emergence application for most plants, doses of about 0.56 to 22.4 kg / ha are used. Such Administration amounts result in a concentration of about 2 to 80 ppm urea, which are distributed over 1.23 ha x cm (soil area x soil depth). For post-emergence use, such as foliar spraying, agents are used that are about 0.06-0.96 kg / 100 liters Spray solution included. This application corresponds to about 0.56 to 22.4 kg / ha.

The herbicidal compositions according to the invention contain a herbicidal amount one or more of the ureas described above, intimately with a biologically inert carrier material are mixed. The carrier can be a liquid Diluent such as water or acetone, or a solid. The Festst.off can be in the form of a dust powder or granules. These funds included usually also auxiliaries, such as wetting agents or dispersants, to ensure penetration in the plant growth media or the plant tissue'Zu so that im their effectiveness is generally promoted. These agents can also contain other pesticides, Contain stabilizers, conditioning agents or fillers.

Claims (8)

P a t e n t a n s p r ü c h e: oil 1-Alkanoyloxyhalogenäthylureas of the general formula where R is an alkyl radical with 1 to 12 carbon atoms, a cycloalkyl radical with 3 to 8 carbon atoms> a phenyl radical which is substituted by up to 2 fluorine, chlorine or bromine atoms or trifluoromethyl, nitro, lower alkyl or lower alkoxy radicals, or a phenylthio, phenoxy or phenylsulfonyl radical which is substituted by up to 2 fluorine or chlorine atoms; R1 is a hydrogen atom or an alkyl radical having 1 to 4 carbon atoms; R2 is an alkyl radical having 1 to 4 carbon atoms; .Z is a chlorine or bromine atom; Y is a hydrogen atom or Z and R3 is a hydrogen atom or an alkyl radical having 1 to 6 carbon atoms. 2. Compound according to claim i, orfn R1 and R3 is a hydrogen atom mean. 3. A compound according to claim 2, wherein Z and Y represent a chlorine atom. 4. A compound according to claim 3, characterized in that R is a Phenyl radical means with 1 to 2 fluorine, chlorine or bromine atoms or trifluoromethyl, Nitro, lower alkoxy or lower alkyl radicals. 5. advertising according to claim 4, wherein R is a phenyl radical, which is substituted with 1 to 2 fluorine or chlorine atoms. 6. 1-Methyl-1- (1-formyloxy-2,2,2-trichloroethyl) -3- (3,4-dichlorophenyl) urea. 7. 1-Methyl-1- (1-formyloxy-2,2,2- * riehloroethyl) -3- (2-fluorophenyl) urea. 8. Herbicidal agent, characterized by a content of at least one of the compounds of claims 1 to 7 as an active ingredient.