JPS604840B2 - Cyanomethylaminomethylphosphonate derivatives and herbicides containing the derivatives as active ingredients - Google Patents

Description

[Detailed description of the invention] The present invention is based on the general formula (1) (R in the formula represents a hydrogen atom, an alkyl group, or a group.

However, X represents a halogen atom, a lower alkyl group, a lower alkoxy group, or a lower alkoxycarbonyl group.

) and a herbicide containing the derivative as an active ingredient. Until now, only paraquat and glyphosphate have been put into practical use as foliar herbicides, but foliar herbicides are effective labor-saving agents, and the demand for them is expected to increase significantly in the future. is expected.

Although the paraquat agent is an excellent herbicide, it is highly toxic and must be treated with great care.
Furthermore, glyphosphite is an effective herbicide for perennial weeds, but there are many problems with the manufacturing method, especially the need for protective groups, so for consumers, neither of these drugs is a perfect herbicide. hard. The present inventors have conducted extensive research into herbicides containing as active ingredients compounds that have strong herbicidal activity comparable to paraquat agents or glyphosphate agents, and can be produced much more easily than glyphosphate agents. Having discovered that the novel compound of the present invention has excellent herbicidal activity, the present invention has been completed and proposed herein.

The compound of the present invention has the advantage that it can be obtained in high yield from inexpensive starting materials by the method shown in the following formula and does not require a protective group.

○ Reaction route when R in general formula (1) is a substituted phenyl group (X in the formula represents a substituent.

) As shown in the reaction route above, substituted phenol and phosphorus trichloride are reacted to produce tri(substituted phenyl) phosphite, which is further hydrolyzed with water to obtain di(substituted phenyl) phosphite (reaction formula reference).

It goes without saying that the di(substituted phenyl) phosphite can also be obtained by other methods. The resulting di(substituted phenyl)phosphite and methyleneaminoacetonitrile are reacted in the presence of an acid catalyst such as BF3 to obtain a phosphonate corresponding to general formula (b) in high yield. Hydrolysis of this phosphonate gives the compound of the present invention,
The substituted phenol produced in this reaction step can be easily recovered, which is an advantage of the production method of the present invention compared to the conventional method of introducing a carboxymethyl group as a protecting group without the outflow of raw materials (reaction process). (See formula@). ○ R in general formula (1)
Reaction path Q when is hydrogen Ratio P030Me3SI
CI→(Me3Sj0)2POH (Me in the formula represents a methyl group.

) As shown in the reaction route above, di(trimethylsilyl)phosphite is produced by reacting head phosphoric acid with trimethylchlorosilane, and the phosphite is reacted with methyleneaminoacetonitrile in the presence of BF3 to form the general formula (m). The corresponding phosphonate is obtained.

The compound of the present invention can be obtained by decomposing the phosphonate with a compound having active hydrogen, such as acetic acid, methanol, ethanol*, water, etc. (see reaction formulas ① and ＠). This reaction yields the target product almost quantitatively in high yield. The silyl compound used in the reaction has the advantage that it can be recovered and reused by using acetic acid or the like.

○ Reaction route when R in general formula (1) is an ethyl group As shown in the reaction route above, a heterogenization reaction between di(trimethylsilyl) phosphite and dialkyl phosphite is performed to produce ethyltrimethylsilyl phosphite. (See reaction formula @).

When the obtained phosphite is reacted with methyleneaminoacetonitrile in the presence of an acid catalyst as described above, the general formula (W
) is obtained. The phosphonate (W) is decomposed with ethanol to produce the monoethyl phosphonate of the compound of the present invention (see Reaction Scheme 6). This reaction 6 is also a method that can produce the target product in a very high yield. The compound of the present invention can be easily produced from methylene aminoacetonitrile as a raw material, which is easily obtained from formalin, ammonium chloride, and sodium cyanide, and without the use of a solvent in the reaction.

Further, the reaction temperature is not particularly limited, but generally a range from room temperature to 120° C. is suitable, and although the reaction can be produced in the absence of a catalyst, an acid catalyst, particularly BF3, is preferred. Note that although the phosphonate produced after the reaction is usually separated and subjected to a post-decomposition reaction, a product close to the pure product can be obtained even if the decomposition reaction is subsequently performed without separation. Next, synthesis examples of the compounds of the present invention will be specifically explained.

Synthesis Example 1 p-Chlorphenylcyanomethylaminomethylphosphonate.

Tri-p-trichloride obtained by reacting 20.02 (0.145 mol) of phosphorus trichloride, 56.1 (0.437 mol) of p-chlorophenol, and 44.1 (0.437 mol) of triethylamine. 58.6 mols of chlorphenyl phosphite (0.142 mol) was dissolved in 80 ml of dry tetrahydrofuran, 2.5 ml of pure water (0.139 mol) was added, and the mixture was heated at 40 to 50°C for 1 hour. I worshiped a heated rope.

After the reaction solution was brought to room temperature, 9.5 methylene aminoacetonitrile (0.139 mol) and 47% boron trifluoride ethyl ether solution 3' were added and heated at 50°C for 1 hour. After the reaction, the solvent was removed, the oily residue was dissolved in 150% of acetone, 4.0% of pure water was added, and the mixture was left at room temperature overnight. White crystals are formed by reconsolidation with sulfoxide 17.
I got 3 nights. The crystals began to brown at 170 oo, and at 18
It completely turned black and decomposed at 1°C.

In addition, the crystal has an infrared absorption spectrum of 250
Hydrogen bonds were observed near 0 skin-, 1592 skin-, 1490 skin-, phenyl groups, and absorption indicating the presence of phosphonates was observed at 1230 arc-, 1080 skin-. In addition, the IH nuclear magnetic resonance spectrum measured in trifluoroacetic acid is
64.10 shows the doublet peak at J=14.0HZ indicating the presence of a methylene group adjacent to the phosphorus atom, and 67.25 shows the peak showing the presence of p-chlorosubstituted phenyl in a hydrogen number ratio of 1:1. Shown at a ratio of 1:2. Based on the above results, the white crystals were confirmed to be Synthesis Example 2 p-10 methoxycarbonylphenyl cyanomethylaminomethylphosphonate.

Tree p- obtained by reacting 20.0 moles (0.145 moles) of phosphorus trichloride, 66.4 moles (0.437 moles) of methyl paraoxybenzoate, and 44.1 moles (0.437 moles) of triethylamine. Methoxycarbonylphenyl phosphite (69.3 moles) was dissolved in 80 moles of dry tetrahydrofuran, and 2.6 moles (0.144 moles) of pure water was dissolved in 80 moles of dry tetrahydrofuran.
mol) was added and heated for 2 hours at 40:00.

After the reaction solution was brought to room temperature, 10.0 mol (0.147 mol) of tyreneaminoacetonitrile and 3 ml of a 47% ethyl boron trifluoride solution were added, and the mixture was heated at 40 to 50°C for 2 hours. After the reaction, the solvent was removed, the residue was dissolved in 150 ml of acetone, 4.0 ml of pure water was added, and the mixture was allowed to stand overnight at room temperature. The crystals were recrystallized with a mixed solvent of 1:1 of hydrogen and pyridine to obtain 16.52 white crystals. The temperature of the crystal is 179℃
It started to change color at 186℃ and completely turned black and decomposed at 186℃.

In addition, the crystal has an infrared absorption spectrum of 250
Urei-, nearby hydrogen bond, 1720-, benzoic acid ester, 1605-, 150&res--, phenyl group,
122 ratio 1-, 1076-, showed absorption indicating the presence of phosphonate. In addition, the H nuclear magnetic resonance spectrum measured in trifluoroacetic acid shows a doublet peak at J=14.4HZ at 64.12, indicating the presence of a methylene group adjacent to the phosphorus atom, and a doublet peak at 84.16. The singlet peak indicating the presence of the methyl group of carboxylic acid methyl ester is
．． The singlet peak at 66 indicates the presence of the methylene group in acetonitrile, and the peaks at 7.32 and 68.12 indicate the p-substituted phenyl group, with a hydrogen number ratio of 2:3, respectively.
:2:4 ratio. From the above results, it was confirmed that the white crystal was.

Synthesis Example 3 Synthesis of N-(phosphonomethyl)aminoacetonitrile 24.5 moles of phosphorous acid (0.3 mol) and 50 moles of dry benzene were placed in a Mitsuro flask equipped with a calcium chloride tube and a Dimroth, and the mixture was heated to 5,000 ml. At the same time, 97.8 mol (0.9 mol) of trimethylsilyl chloride was added dropwise over 1 hour.

After the dropwise addition, the mixture was heated under reflux until no more hydrochloric acid gas was generated, and then distilled to remove the benzene under reduced pressure.
/11 o/3 rib Hg, literature value: 74-75 o/3 rib Hg, Chemical Abstracts, 52 萱, 7128 pages, 19 plateaus). Yield: 87.0% A mixture of 29.4 moles (0.13 moles) of the above bistrimethylsilyl phosphite and 9.02 moles (0.13 moles) of 98% methyleneaminoacetonitrile was placed in a three-meter flask with a calcium chloride tube. 4
Boron nitride ethyl ether solution 5' was added dropwise while stirring at 0 to 50 pm, followed by heating for 2 hours.

After the reaction is complete, cool to room temperature and add 100 parts of methanol and 5 parts of water.
．． Upon addition of 0.3 moles, white crystals were precipitated. The crystals were collected in a furnace, washed with methanol, and dried under reduced pressure to obtain 17.01 cm of white crystals. The crystals were reconsolidated with water. (Melting point: 185-187 pm). Yield 87.2%.
The crystal has an infrared absorption spectrum of 1170 skin-
・, 1070 arc-, 950 arc-, showed strong absorption. In addition, the proton nuclear magnetic resonance spectrum measured in heavy water solvent shows a methylene proton signal adjacent to the phosphorus atom at 63.28 (J=13.0HZ, double line), and 64
．． 30 shows the methylene proton signal (single line) adjacent to the cyano group. In addition, the actual value of differential analysis is
N: 18.40%, C: 24.10%, H: 4.32%
The theoretical values of phosphonomethyleneaminoacetonitrile are N: 1866%, C: 24.01%, H: 4.70%
There was good agreement. From the above results, it was confirmed that the crystal was.

Next, Table 1 shows the compounds of the present invention produced according to the above examples.

However, the compounds of the present invention are not limited to these. In addition, the compound numbers shown in Table 1 are test examples,
Referenced in the Examples. When putting the compound of the present invention into practical use, the compound of the present invention is diluted with a suitable carrier, and if necessary, emulsifiers, dispersants, suspending agents, spreading agents, wetting agents, etc. are added to prepare powders, It is used in various forms such as granules, wettable powders, and emulsions.

It can also be used in combination with other herbicides, fungicides, insecticides or fertilizers. Next, a test example for confirming the herbicidal effect of the compound of the present invention will be shown.

Test example 1 ± Weeding effect test by soil treatment In a plastic box with 15 skins vertically, 22 sections horizontally, and 6 skins deep,
Sterilized Hongtong soil was added and mixed with rice, grasshopper, crabgrass, cyperus, koakaza, purslane, doggrass, tomato, and cucumber, and after approximately 1.5 skins were covered, the compound of the present invention was added at a rate of 25 m/a. It was sprinkled on the surface of the soil in a spreading motion.

The chemical solution used for spraying was the emulsion of Example 1 described later, which was diluted with water to 50% and then sprayed over the entire surface with a small sprayer. After spraying the chemical solution three times, the herbicidal effect on rice and various weeds was longitudinally investigated using the following criteria.

The results are shown in Table 2. Criterion 0: No herbicidal activity (
Same as untreated) 2...Compare above-ground grass wings with untreated area 90% or more2
… 〃 〃 60-90%3…
〃 〃 20-60%4...
・ 〃 〃 20% or less 5...Complete withering test example 2 Weeding effect test by stem collection treatment In a plastic box with 15 arcs vertically, 22 skins horizontally, and 6 arcs deep,
Sterilized diluvial soil was placed in the soil, and seeds of rice, Japanese knotweed, crabgrass, cyperus japonica, Koakaza, purslane, dogberry, leafminer, tomato, and cucumber were sown in spots to cover about 1.5 liters of soil.

When paddy rice, tomatoes, radish, and weeds reached the 2nd to 3rd mulberry stage, the compound of the present invention was sprayed onto the stem straw at a rate of 25 m/a. The chemical solution used for spraying was the emulsion of Example 1 described below diluted 150 times with water and sprayed using a small sprayer over the entire surface of the stems of paddy rice, tomatoes, radishes, and weeds. Two weeks after spraying the chemical solution, the herbicidal effects on rice, tomatoes, radish, and weeds were investigated according to the criteria described in Test Example 1. The results are shown in Table 2. 2nd expression) Processing method. "Soil" described in this column represents the herbicidal effect of soil treatment, and "stem and foliage" represents the herbicidal effect of foliage treatment.

A×sheep-. ．． ．． ．． 、． ．． The following structural formula represents a control compound.

B. Firefighter. ．． ...Represents a control compound with the following structural formula.
Test Example 3 Testing the herbicidal effect of pots in a greenhouse Seeds of the weeds listed in Table 3 were sown in 4-inch clay pots and grown in a greenhouse until the 3rd to 4th straw stage, when the specified amount of the compound of the present invention was observed. was made into an aqueous solution (with the addition of a commercially available spreading agent) and sprayed on the entire surface in an amount of 15 times per area (2 repetitions).

The investigation was conducted 3 weeks after the drug treatment according to the criteria of Test Example 1. The results are shown in Table 3.

Table 3 (Kotoaki) Paraquat *...A commercially available herbicide with the following structural formula.

Test Example 4 Outdoor herbicidal effect test A colony of weeds listed in Table 4 was selected, divided into 1 areas, and a prescribed amount of the compound of the present invention was dissolved in 150ml of water (with the addition of a commercially available spreading agent). and sprayed it all over the area.

The investigation was conducted on the 50th day after the drug treatment according to the criteria of Test Example 1. The growth level of weeds during chemical treatment is as follows. ○ Weed growth status during chemical treatment Plant height: 40 to 5 yen (approx.・・・・・・
・・・Oxalis in the beginning of flowering・・・・・・・・・〃 Silver grass in peak season・・・・・・・・・・・・・Plant height 90～looo skin・・・・・・・・・・・〃 40～90 Results are 4th Shown in the table.

Table 4 shows examples of the present invention, but the present invention is not limited thereto.

Note that "part" means part by weight.

Example 1 Emulsion A compound of the present invention, 7...5 parts of dimethyl formamide...35 parts Toximal 500 (trade name of Sanyo Oil & Fats)...15 parts or more are mixed and dissolved to prepare an emulsion.

Dilute this emulsion with water by 70 to 100 centimeters to 50 to 2
Spread 00 so/1 pile. Example 2 Hydrating agent Compound of the present invention. 5 ... 5 parts Zikrite ... 45 parts Solpol 8048 (Toho Chemical brand name) ... 3 parts Lunox 1000 (Toho Chemical brand name) ... 2 or more parts are uniformly mixed and ground to make a wettable powder shall be.

Claims (1)

[Claims] 1 General formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (R in the formula represents a hydrogen atom, an alkyl group, or ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ group. However, X is a halogen atom , a lower alkyl group, a lower alkoxy group, or a lower alkoxycarbonyl group. 2 General formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (In the formula, R is a hydrogen atom, an alkyl group, or ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ group. However, X is a halogen atom, a lower alkyl group, a lower A herbicide containing as an active ingredient a compound represented by (representing an alkoxy group or a lower alkoxycarbonyl group).