DD215535A5 - PROCESS FOR PRODUCING NEW DINITROPHENOLES - Google Patents

Abstract

The invention relates to a process for the preparation of novel dinitrophenols of the general formula (I) in which x is hydrogen, an alkali metal or an alkaline earth metal, an alkyl or an alkenylcarbonyl group having 1 to 10 carbon atoms, an optionally halogen-substituted phenylcarbonyl group or a group of the general formula H deep N high + R deep 1R deep 2Rtief 3, in which R deep 1, R deep 2 and R deep 3 independently of one another hydrogen, an alkyl, an alkoxyalkyl, an alkenyl, a hydroxyalkyl, a Cycloalkyl or an optionally substituted phenyl group. The novel compounds are obtained by reaction of 2-chloro-3,5-dinitrobenzotrifluoride with alkali metal or alkaline earth metal hydroxide in an aqueous medium without catalyst and have a biological activity.

Description

15 897 55

Process for the preparation of new dinitrophenols

Field of application of the invention;

The invention relates to a process for the preparation of novel dinitrophenols. The novel compounds correspond to the general formula (I) wherein

X is hydrogen, an alkali metal or an alkaline earth metal, an alkyl or alkenylcarbonyl group having 1 to 10 carbon atoms j is an optionally substituted by halogen Pheriyi'carbonyl * - group or a group of the general formula

HNR ₁ R ₂ R ₃ stands;

in which R ₁ , R ₂ and R _{3 are} independently of one another hydrogen, an alkyl, an alkoxyalkyl, an alkenyl, a hydroxyalkyl, a cycloalkyl or optionally a substituted phenyl group.

The new compounds have a herbicidal activity. ·. '. : -. , , , .. ..; :. ;! , .I- '. : - ".

Characteristic of the known technical solutions:

It is known that the compounds of general formula (I) structurally related 2-methyl-4,6-dinitrophenol (dinitro-ortho-cresol, DNOC) and its alkali metal salts have a herbicidal and acaricidal activity. Compositions containing this substance as an active ingredient are e.g. Novenda and cresonite. Another known herbicide is 2-sec-butyl-4,6-dinitrophenol (DN8P), a dinitro-ortho-cresol-related compound that can also be used as a biostimulator in maize crops in smaller doses (Uhlrogge, A.- CJ .: The Development of DNBP / Disoseb / as a Biostimulant for Corn in Plant Growth Regulators; Editor: Stutte CA 79 to 87 pp Advances in chemistry series; 159 American Chemical Society, Washinstein, 1977). Production processes have hitherto only become known for compounds which are structurally related to the compounds of general formula (I) according to the invention. The literature gives no indication whatsoever of the preparation of the compounds of general formula (I) and of their biological properties. British Patent 1,378,994 describes the preparation of 2,4-bis (trifluoromethyl) .6-nitrophenol and its derivatives. The preparation of 2,6-dinitro-4-trifluoromethylphenol and its derivatives is described in U.S. Patent 3,813,446. These known processes are carried out in organic solvents, if appropriate in the presence of a phase transfer catalyst. In this case, also run off unwanted side reactions, for example, the formation of ether derivatives in methanolic medium, or the hydrolysis of the trifluoroethyl group to the carboxyl group.

Aim; the invention:

The aim of the invention was a process for the production

to provide the compounds mentioned above, in which the side reactions to be recorded in the known processes do not occur, which is also economical on an industrial scale and leads to products of suitable purity.

Explanation of the essence of the invention;

The compounds of formula I are prepared by preparing in the first step from 2-chloro-3,5-dinitro-benzotrifluoride by reacting with an alkali or alkaline earth metal hydroxide, the corresponding alkali or Erdalkaliphenolat. The reaction is carried out without catalyst in an aqueous medium at 20 to 100 ⁰ C, preferably at 60 to 80 ° C, and a Laugenkonezntration of 5 to 20 wt .-%, preferably 10 to 15 % by weight. The phenolate obtained in the hydrolysis can be converted by means of an acid in a conventional manner into the phenol derivative. If desired, another compound of general formula (I) can be prepared from the resulting phenol (X = H) by reaction with a corresponding base.

The compounds of general formula (I) can be isolated from the reaction mix and R _e may then be processed to pesticides.

The compounds of the general formula (I) obtained by the process according to the invention were tested for their biological effectiveness in the form of different compositions in numerous scientific tests. The experiments have been successful in demonstrating that the compounds of general formula (I) can enrich the selection of pesticidal agents with new herbicidal acaricidal and growth regulating agents.

  , , '- 4 -

The compounds of the general formula (I) are used for the destruction of pests or for the regulation of plant growth.

The novel compounds of general formula (I) enrich the choice of compounds of similar mode of action. Accordingly, they represent an enrichment of the art. The chemical process according to the invention has the advantages of providing these compounds in an economical, simple and readily reproducible manner. A further advantage is that run through the reaction in an aqueous medium, without catalyst, in the hydrolysis no harmful side reactions.

EXAMPLES

The invention will be explained in more detail with reference to the following examples, but is not limited to these examples

Preparation of the compounds of general formula (I)

example 1

In a flask of lOOO cm volume, which is equipped with stirrer, dropping funnel, reflux condenser and thermometer, 300 g of 10 % ± Na NaOH solution ("0.75 moles of NaOH) are introduced g of 2-chloro-3,5-dinitrobenzotrifluoride of 95% purity (= 0.3 mol) The mixture is warmed to 60 ° C. and stirred at 60 to 65 ° C. for 4 hours to give the aqueous suspension a Emulsion.

The reaction mixture is cooled with stirring to room temperature (20 to 25 ° G) and treated within one hour with a 0.83 mol of HCl corresponding amount of 37% hydrochloric acid. During the evenly made

Dosage, the mixture is stirred vigorously. The deposited precipitate is filtered off, washed with water and dried at room temperature to constant weight. 68.1 g of 2-trifluoromethyl-4,6-dinitrophenol having a purity of 94 % (identified with a mass spectrometer connected to the gas chromatograph) are obtained. Yield: 90 %.

Example 2

In a provided with stirrer and reflux condenser enamelled reactor of 250 liters volume 60 kg of water are filled. 32.5 kg of 2-chloro-3,5-dinitro-benzotrifluoride are stirred into the water with stirring through a powder funnel. The reaction mixture is heated to 75 ⁰ C. By means of a metering pump 65 kg 20% sodium hydroxide solution are pumped into the reactor at a uniform rate, the temperature is maintained at 75 to C. The reaction mixture is stirred for another 3.5 hours at the indicated temperature and then cooled to room temperature. Within one hour, 9.5 kg of concentrated hydrochloric acid are added at a uniform rate. The precipitate is collected by centrifugation, washed with water and dried in the air to constant weight. This gives 28 kg of 94.3 % pure 2-trifluoromethyl-4,6-dinitro-phenol . Yield: 92.4%.

Preparation of the compositions:.

Example 3 60% strength by weight emulsion concentrate (EC 60)

433 g of 2-trifluoromethyl-4,6-dinitrophenol (97%) are dissolved at 40 ° C in a mixture of 200 g of isophorone and 25 g of xylene. The solution is cooled to room temperature

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and filtered through a pore size GAF filter O, l. 36 g of Tensiofix B 7425 and 6 g of Tensiofix LS are added with stirring to the filtrate as emulsifier.

Example 4 ^v 60% strength by weight emulsion concentrate (EC 60)

It works in the manner described in Example 3, but uses instead of isophorone cyclohexanone and instead of xylene, the solvent aroraatol. The emulsifiers used are the products mentioned in the following table

emulsifier in g: A B C Tensiofix AS Tensiofix LS Emuisogen EL Sapogenate T 180 Sapogenate: T 500 18 24 12 10 20 10 25 7 Example 5

20% strength by weight water-soluble concentrate (WSC 20)

To 300 g of a 30% aqueous solution of 2-trifluoromethyl-4 _# 6-dinitro sodium saponate are added as emulsifier 50 g of xylene glycol and 4 g of Tensiofix CG-21. The solution is made up with stirring with desalted water to 450 g.

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Example 6 20% by weight oily paste

620 g of 2-trifluoromethyl-4,6-dinitrophenol are dissolved in 500 g of cyclohexanone and added to the solution 120 g of cosmetic Vaseline oil. With the aid of an Ultra-turrax mixer, the resulting solution is emulsified with a 10% solution of the emulsifier Tensiofix PO-132, wherein the temperature is maintained at 30 ⁰ C. The mixture is cooled to 15 ⁰ C. Within one hour, the 0.2% solution of Kelsan S in ethylene glycol in an amount of 50 g in the Geraisch is distributed with slow stirring.

Vvi rkungsunt requests

Example 7 Examination of the herbicidal action in the greenhouse

The seeds of white mustard, curly amaranth, white goosefoot (reporting), Italian fennich, winter wheat and corn were sown in seed pots. After emergence, the plants were sprayed in the 2-4 leaved stage with 0.2% spray liquor (prepared by diluting 10% EC and WSC preparations prepared from the test compounds), each compound being applied in the amounts of 2.5 , 5 and 10 kg / ha was tested. On the 14th day after the treatment, the damage to the plants was determined in percent. The results are summarized in Table 1.

Table 1

connection

Dose mustard Amakg / ha ranth

Goose Fen- wheat corn foot nich

2-trifluoromethyl-4,6-dinitrophenol 1.25 45 50 8th 75 O O O 2.55 75 85 90 10 5 5 5.0 95 100 100 30 10 15 2-trifluoromethyl-4,6-dinitrophenol diethanolamine 1.25 2.5 5.0 40 60 80 50 60 85 70 75 80 O 10 O 10 O 10 2-trifluoromethyl-4,6-dinitrophenyl dimethylamine 1.25 2.5 5.0 45 55 75 50 65 80 70 75 85 O O 20 O O 10 O O 10 2-trifluoromethyl-4,6-dinitrophenol-sodium. 1.25 2.5 5.0 50 80 100 60 85 100 70 90 100 O lo 15 O O 15 O 10 15 2-trifluoromethyl-4,6-dinitrophenol potassium 1.25 2.5 5.0 65 75 90 45 85 100 70 90 100 O 10 15 O O 15 O 10 15 example

Determination of inhibition of the Hill reaction

Using the method of Arnon et al., Chloroplasts were isolated from spinach. To one gram of the strains of purified spinach leaves was added 6 ml of 0.35 molar saline and 0.6 ml of 0.2M TRIS buffer. The whole was ground, filtered through several layers of gauze and then centrifuged at a speed of 200 for 5 minutes. The chloroplast precipitate. was suspended in 0.035 molar saline, homogenized in the Potter tube and the resulting chloroplast suspension stored at ⁰ ° C. until use.

  ·. '_ g _

A mixture is prepared from the chloroplast suspension and K ₃ Fe (CN) ₆ , K TRIS.HCl buffer and MgCl 2

Solutions of the compounds of the general formula (I) (as inhibitors) or solutions of N- (3,4-dichlorophenyl) -N *, N'-dimethylcarbamide (corresponding to standards) are prepared in the concentration range from 10 to 10 ~ mol. DCMU) and dinicroortho-cresol (ONOC). The resulting mixtures are exposed for 20 minutes to an illuminance of 5000 lux. Then the reaction is stopped by the addition of 25% trichloroacetic acid (TCA). The precipitate is removed by centrifugation and the absorbance of the solution is measured at 420 nm with a Spectrophotometer 204 spectrophotometer. The series of measurements is repeated with samples kept in the dark. Inhibition of the Hill reaction was determined by the difference in absorbance of light and dark samples and converted to μg / ml of potassium ferrocyanide by a calibration curve. (The Pozentwerte of inhibition was plotted against concentration and from the curve belonging to a 50% inhibition concentrations were read (I _50).

The results are shown in Table 2.

I (Mikcomol / compound ^DUJ drri)

2-trifluoromethyl-4,6-dinitrophenol 0.21

2-4,6-dinitrophenol Triflüormethyl-

diethanolamine 0.57

2-trifluoromethyl-4,6-dinitrophenol

dimethylamine 0.52

2-trifluoromethyl-4,6-dinitrophenol-NH ₄ 0.25

2-trifluoromethyl-4,6-dinitrophenol-Na 0.20

2-trifluoromethyl - ^^ e-dinitroghenol-K _ _ 0 ^ 31 ^

Comparison substances:

Dinitro-oitho-cresol-Na 0.86

rN ¹ , N'-dimethylcarbamide 0.071

From these data it can be seen that 2-trifluoromethyl-4,6-dinitrophenol and its salts are similar to the N- (3,4-dichlorophenyl) -N *, N'-dimethylcarbamide inhibitors of the second photochemical system and their effectiveness is approximately between that of N- (3,4-dichlorophenyl) -N ', N'-dimethylcarbamide and dinitro-ortho-cresol. Of the new compounds in this test, the amine salts are more efficient than the alkali and ammonium salts.

Example 9 Investigation of herbicidal activity on maize (field)

The investigations were carried out with the formulated according to Example 5 2-trifluoromethyl-4,6-dinitrophenol-Na WSC 20 or formulated according to Example 3 2-trifluoromethyl-4,6-dinitrophenol EC 60. On 25./26. In April, brown kernels of the variety Pioneer 3950 were seeded in brown forest soil containing 1.8 % of organic matter, with a bacterial count of 7300OO / ha 8-10 cm deep. On May, sprayed with a Parzellensprühvorrichtung (spray head Tee-Det 11 002, 1.5 atm pressure) and a Wasseraufnandmenge of 300 liters / ha. At this time, most corn plants had 3, -4 leaves, most weeds 2-4 leaves. The composition was tested in four parallel experiments. At the time of treatment, the area was 87.5 % covered with weeds. Of these, 58 % were amaranth, 27 % goosefoot and the remainder ranunculus. The effect was evaluated on 15, Ouni. The herbicidal activity on the weeds and the phytotoxic effect on maize were determined using the EEAC scale.

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Table 3 shows the rating scale, in Table 4 the results are summarized. Oeder value is the mean of 4 parallel experiments.

Table 3

EWRC value scale 100 90 Damage to crops in percent I. V / Q VVe r t Un herbiv ers destroying effect % 99 75 none O L excellent 98 50 very weak 1 2 excellent , satisfactory 95 25 weak 2 3 Well adequately O weak to moderate 5 4 insufficient Table 4 mäßij 10 5 bad mediocre 25 6 very bad , strongly 50 7 unusable very strong 75 8th complete destruction 100 9 EWRC-We r te ϊ for different plants

Active substance and dose of 2-trifluoromethyl-4,6-2-trifluoromethyl

dinitrophenol-Na 4,6-dinitrophenol

Plant 20 WSC 60 EC

5 l / ha 10 l / ha 1.6 l / ha 3.2 l / ha

Amaranth 3 1 10 »5 4 2 white geanut foot 2 1 3.5 1 Echinpchloa 2 7 3, 5 Corn 1.5 1 , 5 1 .1 example

Growth and earnings support for corn

On April 20, maize of the MVSC 3780 variety with a germination

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number of 55 OOO / ha, sown. At the beginning of the flowering period, on the 22nd Duii, a helicopter was sprayed with 2-trifluoromethyl-4,6-dinitrophehol ~ Na (20 VVSC). The application rate was 0.25 liters / ha (= 0.05 kg / ha). Both of the parallel experiments were carried out on a 4 hectare plot. Per hectare 50 liters of water were used. The corn was harvested on 3 November. The

 ..! * '' '. - '' ·

Results are summarized in the following Table 5.

  · ·. ι. . · '. , '... ·

Table 5 Parameters Experiment I Experiment II Control

Flask length 7 cm 16.07-2.19 17.06-2.71 17.33-1.87

Proportion of not completely

filled with grains

Piston, '.% 62 66' 84

filled with grains

Part, of the piston _{cm lAt52} t ₂ , 80 15.35 i 3.93 15.33 Ϊ 2.48

% 90.35 93.34 89.97

Weight of a piston, g 229.6 i 6 208.4 - 5 191.6-4

Crop yield, t / ha 4.25 4.08 3.55

in the

Control 119.5 114.9 100

The experiments have shown that the 2-trifluoromethyl-4,6-dinitorphenol-Na exerts its yield-increasing effect over larger grains and better occupation of the flask with grains.

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Example 11

Investigation of the acaricidal activity

The tests were carried out on apple trees (Golden delicius) planted at intervals of 7.5 m χ 4.5 m. On 16 March, before the sprouts were sprouted, sprayed from a Haflinger sprayer with a high-pressure spray gun (20 bar). 48 hours after the treatment, 5 × 10 fruit shoots were collected from each plot, whether treated or untreated (5 trees grew on each plot) and observed in the laboratory until all the mite mites had hatched in the case of untreated control (12 , Day). Mortality was calculated from the number of exfoliated mites as a percentage of the control and the results are given in Table 6.

composition

Table 6 ·

Conc. Hatched respiratory Disease in% Mites (pieces) bene eggs of Conaus 5x10 shoots % trolls

2-trifluoromethyl-4,6-dinitrophenol-Na 20 WSC

2-trifluoromethyl-4,6-dinitrophenol EC 60

2.5

0.8

Dinitro-orthocresol

(DNOC-25) paste 2.0

untreated control -

27

521

96, 35

95.59

94.82

3.65

4.41

5.18

100

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! You exceed compounds of general formula (I) As the table shows, the effect of the reference substance uinitro-ortHQ-cresol (paste Novenda 25).

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ο-χ

O ₂ N

^CF 3 I

NO,

Claims (3)

Claim of invention: 1. A process for the preparation of dinitrophenols of the general formula (I) wherein X represents hydrogen, an alkali metal or an alkaline earth metal, an alkyl or alkenylcarbonyl group having 1 to 10 carbon atoms, an optionally halogen-substituted phenylcarbortyl group or a group of the general formula HNR ₁ R ₂ R ₃ is, ^ in which R-, R ₂ and R ₃ independently of one another represent hydrogen, an alkyl, an alkoxyalkyl, an alkenyl, a hydroxyalkyl, a cycloalkyl or an optionally substituted phenyl group, characterized in that hydrolyzed 2-chloro-3,5-dinitro-benzotrifluoride with an alkali or alkaline earth metal hydroxide in an aqueous medium in the absence of catalysts and the phenolate obtained, if desired, to give phenol or other compounds of general formula (I). 2. The method according to item 1, characterized in that one dia hydrolysis at a liquor concentration of 5 to 20 wt. ->%, preferably 10 to 15 wt .-%, performs. 3. The method according to item 1 or 2, characterized in that one carries out the hydrolysis at temperatures of 20 to 100 ⁰ C, preferably 60 to 80 C, performs. - For this purpose 1 formula sheet - - 16 r- ·