DE2040628A1 - Substd hydroxyguanidines prepn - Google Patents

Abstract

Hydroxyguanidines (I): (where R and R1 independently = H, C1-6 alkyl, aryl or aralkyl or NRR1 = a heterocyclic ring; R2 and R3 independently = alkyl, alkoxy, alkylthio, Hal, NO2 or opt. substd. NH2 and (m+n)=5) which are intermediates for drugs and plant protection products, are prepd. by reaction of arylimino-halogen-carbonic acid amides or their salts with 1-3 mol. equivs. of an oxime in a dry organic solvent or in water or in aprotic organic solvent. Water has the advantage of providing a soln. of the oxime e.g. acetoxime. (I) appears in the aqs. soln. as the H-halide salt from which the base is pptd. in the presence of basic cpds. e.g. alkali carbonates, ammonia or organic bases.

Description

New herbicidal compositions The invention relates to new herbicidal compositions which are characterized by a content of compounds of the general formula I or their salts with organic or inorganic acids.

In formula I, R and R1 independently represent hydrogen, Alkyl groups with 1 to 6 0 atoms, aryl radicals or aralkyl groups and also can together with the material atom, they are part of a ring which, if applicable is interrupted by further heteroatoms. R2 and stand independently of each other for alkyl radicals, halogen atoms, nitro groups, alcohol or alkylthio groups and amino respectively.

substituted amino groups; n and m are integers from 0 to 5, where n + m is c 5.

These compounds are obtained in the reaction of correspondingly substituted aryliminohal ogenkohlens acid amides of the formula II with hydroxylamine or, in the reaction, appropriately substituted isoureas or isothioureas of the formula III with hydroxylamine. These reactions correspond to the known synthesis of ganidines from isoureas or isothioureas and amines and can be carried out under the same conditions.

It was surprising and unforeseeable that the so produced Hydroxyguanidines of the formula I are excellent for total weed killing and for the selective control of unwanted vegetation in root crops and cereal crops as well as in other cultures.

The herbicidal compounds can, depending on the intended mode of application with suitable carriers and / or diluents and surface-active agents Substances for fuel powders, emulsifiable concentrates, granules or solutions be formulated, wa an optimal distribution and distribution of the funds To ensure the effectiveness of the active components. in addition, the active ingredients applied in the form of their water-soluble salts with organic or inorganic acids will.

Depending on the area of application, the active ingredients can be pre- or post-emergence in application rates between 0.5 kg / ha and 20 kg / ha asgsirrandt, the active ingredients act as total herbicides in the higher application levels.

The herbicidal compositions according to the invention can be used to broaden their Spectrum of activity and to achieve synergistic and selective effects with others suitable herbicides can be combined and applied.

When comparing the numerical values of the application example (3) recognizes one that the described hydroxyguanidine especially in the pre-emergence treatment exhibits equally good to better hertisidal properties in beet crops than zua Example the well-known beet herbicide Benzthiazuron.

The following are some of the general formula of Hydroxyguanidines I and their herbicidal action described in more detail, but without the invention limit the examples given. It takes similar to the corresponding Urea herbicides with increasing chain length of the radicals R and R1 are the herbicidal Effectiveness of the connections. On the other hand, it causes a substitution in the aromatic one Part of the molecule with chlorine, bromine, nitro, amino or substituted amino groups generally increased herbicidal effectiveness and often concurrently one Shift in the spectrum of action.

The synthesis of these compounds can be carried out according to the methods described in Example 1 and 2 carry out the procedure described. Table 3 shows some examples of these Compiled compound class, but without restricting the invention.

Example 1 4.1 g (0.05 mol) of hydroxylammonium chloride are in 30 mm Dissolved dry methanol and cooled to 0 to -5 ° C.

4.2 g (0.075 mol) of methanolic potassium hydroxide solution are added dropwise at this temperature to, whereby a finely crystalline precipitate is formed. The mixture is stirred for a further 30 minutes and the mixture is mixed with 4.0 g (0.025 mol) of N-phenyl-N ', N'.S-trimethylisothio urea, dissolved in 10 ml of dry methanol. The naatz is stirred for a further 3 hours and then warmed to room temperature. After most of the solvent has been distilled off the remaining residue is poured into water and the precipitated product sucked off.

After drying, it is made up of benzene / gasoline (1: 1). yield 0.8 g (18% of theory) mp 134-36.5 ° C.

Example 2 1-Hydroxy-2-phenyl-3.3-dimethylguanidine The procedure the reaction corresponds to Example 1 using N-rhenyl-N'.N'.0-trimethylisourea as a starting product.

Yield 2.1 g (48% of theory) F. 134-136 ° C.

Example 3 In an field test, the 1-Hydroxy-2-phenyl-3.3-dimethylguanidines as a selective herbicide in beets in a Application rate of 5 and 10 kg of a 50% formulation in 1000 l of water / ha The pre- and post-emergence treatment achieved the following results, which are shown in Table 1 are shown. The rating was carried out 8 weeks after the beets had risen.

The numbers given in Table 1 are rating values, which are as follows The key is based on: Score control success in the case of damage to weeds, crop plants 1 Weed population totally no damage destroyed 2 approx. 90% of the conspicuous plants low mass destroys traces of damage 3 approx. 70 s of the plants - plants low im mass destroys growth inhibited 4 approx. 50% of plants - plants medium strength mass destroyed inhibited or 15% of the leaf mass destroyed 5 approx. 30% of the plant Plants strongly inhibited mass destroyed or 30% of the leaf mass destroyed 6 approx. 15% of the plant-plants strongly inhibited mass destroyed or 50% of the leaf mass destroys 7 weed pests a few plants inclined greatly reduced inhibits or 70 % of the leaf mass destroyed. 8 Effect very low Plants almost completely dead 9 no effect plants totally destroyed Table 1 Pre-emergence treatment 1st attempt 2nd attempt 3rd attempt U K U K U K Application rate 5 kg / ha (50%) 2 1 4 1 3 1 application rate 10 kg / ha "1 1 2 1 2 1 untreated control 9 1 comparison agent Bensthia- 3 1 zuron (6 kg / ha) commercial spray powder Post-emergence treatment 1st attempt 2nd attempt 3rd attempt U K U K U Application rate 5 kg / ha (50%) 3 1 3 1 4 1 Application rate 10 kg / ha (50%) 2 4 2 4 2 3 untreated control 9 1 comparison agent Phenmedi- 3 1 pham (6 kg / ha) commercially available emulsifiable concentrate U = weed plants K = crop plants The damage to the individual weed species is shown in Table 2 in which, as a result of an experiment with three repetitions, the number of plants that are still viable at the time of rating are indicated.

Table 2 Pre-emergence treatment of weed species Ch Th St M Pl Lp Cp grasses Application rate 5 kg / ha 5 6 1 1 1 10 - 2 Application rate 10 kg / ha - 1 1 - - 7 - 1 untreated Control 12 10 5 16 1 12 2 6 Reference agent (8 kg / ha) - 3 1 3 1 2 - -combination preparation Proximpham-Diuron-Propham post-emergence treatment Application rate 5 kg / ha 1 7 2 4 1 5 1 application rate 10 kg / ha 1 2 1 1 1 1 1 1 untreated control 11 19 6 14 3 6 1 5 Comparison means 1 1 1 6 - 1 - 1 Phenmedipham (6 kg / ha) Ch Chenopodium album Th Thlapsi arvense St Stellaria media M Matricaria chamomilla Pl Polygonum spec.

Lp Lamium spec.

Cp Capsella bursa-pastoris Patent claims 1. New herbicidal agents, characterized in that they contain compounds of the general formula or their salts, where R and R1 independently represent hydrogen, alkyl groups with 1 to 6 carbon atoms, aryl radicals or aralkyl groups and, together with the nitrogen atom, can also be components of a ring which is optionally interrupted by further heteroatoms, and R2 and R3, independently of one another, represent alkyl radicals, halogen atoms, nitro groups, alkoxy or alkylthio groups and amino or substituted amino groups, where m and n are integers from 0 to 5 and n + m is P 5.

2. Herbicidal agents according to claim 1, characterized in that the effective compounds with suitable carriers and / or diluents and surface-active substances into wettable powders, emulsifiable concentrates, Granules or solutions can be formulated.

3. herbicidal agents according to claim 1 and 2, characterized in that that they additionally contain other herbicidally active compounds as combination components contain.

Claims (1)

Table 3 Cl- / f7 \ 3 Z.138139,5OO (decomp OH Nile 3 oa -N = kos 142.5-14350G decomposed- NH ctl OH Br- N ~ a ~ o 3 F. 140-14200 1 P, Nile OH 3rd OH F. P, 31.5-3300 E a2R5 OH -N-01-N 0 r. 161 - i630a NE OH ) -EsC-E) 3 r. 14O-142.50a Nile OH 13th a L4E XEt CilH3 '2 r. 102-10400 EEI ca2, 44R) OH 0il3 O N. X2 C: E. 9 ° N ° C N CHa, RE ,; OH