JPH0161107B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to N-(1,3
-dioxolan-2-ylmethyl)-N-(2-
The present invention relates to a herbicidal antidote containing this compound (propenyl)-2,2-dichloroacetamide as an antidote, and a process for producing this compound.

Here, R is 2-propenyl.

As represented by the formula, the compounds of the invention are useful for protecting growing crops, such as corn, from the phytotoxic effects of active herbicides, especially S-alkylthiocarbamate and chloroacetanilide herbicides. It was found to be extremely suitable. The compounds of the invention have been found to exhibit particularly effective long-term detoxifying effects, ie lasting for 3 weeks or more after application;
-ylmethyl)-N-(2-propenyl)-2,
2-dichloroacetamide, a compound of formula.

Cyclic diacetal compounds of the formula are derived from diacetal compounds of the formula.

where R is 2-propenyl and
R ⁵ and R ⁶ are alkyl groups having up to 4 carbon atoms.

The compound represented by the formula is the following formula (where R, R ⁵ and R ⁶ are as specified above) appropriately substituted N-(2,2-
Dialkoxyethyl) amines may be produced by reacting a tertiary amine with at least an equimolar amount of dichloroacetyl chloride in the presence of an acid acceptor such as triethylamine. Preferably the reaction is carried out in the presence of an inert organic solvent such as methylene chloride or benzene. This reaction typically runs from 0°C to room temperature, i.e. 20°C to 23°C.
The reaction is carried out at a temperature in the range of 0.degree. C. for a period of time sufficient to obtain the desired degree of conversion. The time period may range from several minutes to several hours. Once this reaction is complete, the reaction mixture is washed with dilute acid, dried and
It is then removed from the solvent. The product is typically obtained in liquid, substantially pure form and generally requires no further purification.

Cyclic diacetal compounds of the formula are prepared by preparing a diacetal compound of the formula in the anhydrous state and in the presence of an inorganic or organic catalyst, such as sulfuric acid or p-
In the presence of something like toluenesulfonic acid,
It can be easily produced by reacting with at least equimolar amounts of ethylene glycol. This reaction is typically carried out at an elevated temperature, for example 90°C to 120°C, for a time sufficient to obtain the desired degree of conversion. The reaction product is then washed, dried and worked up in known manner.

EXAMPLES The following examples illustrate the production of certain detoxifying compounds of the present invention.

Example 1 (a) N-(2,2-dimethoxyethyl)-N-
Formation of (2-propenyl)-2,2-dichloroacetamide Place a three-necked flask in an ice bath and place 2.9 grams (0.02 mol) of N-(2,2-dichloroacetamide) in the flask.
-dimethoxyethyl)amine and 2.02 grams (0.02 moles) of triethylamine dissolved in 100 milliliters of methylene chloride. 2.95 grams (0.02 moles) in this stirred mixture
A solution of dichloroacetyl chloride dissolved in 5 milliliters of methylene chloride is added dropwise over a period of at least 15 minutes. Add this reaction mixture to 30
Stir for a minute, remove from ice bath, and stir for an additional 3 hours. By then the reaction mixture has reached room temperature. This reaction mixture is then
Washed with 50 ml portions of 10 percent aqueous hydrochloric acid, dried with magnesium sulfate,
It is then concentrated in a rotary evaporator at a temperature not exceeding 50°C to produce a pale pink liquid.
Obtained 4.96 grams. It was identified by NMR spectroscopy as N-(2,2-dimethoxyethyl)-N-(2-propenyl)-2,2-dichloroacetamide.

(b) Production of N-(1,3-dioxolan-2-ylmethyl)-N-(2-propenyl)-2,2-dichloroacetamide produced as described in (a) above.
15.0 grams (0.059 mol) of N-(2,2-dimethoxyethyl)-N-(2-propenyl)-
2,2-dichloroacetamide and 6.2 grams (0.1 mole) of ethylene glycol and two crystals of p-toluenesulfonic acid were placed in a round bottom flask. The reaction mixture was heated at about 110° C. for 4 hours, and the methanol generated was distilled off. The reaction mixture was then cooled, poured into 100 milliliters of methylene chloride, and washed once with 50 milliliter portions of 10 percent aqueous sodium hydroxide and twice with 100 milliliter portions of water. The washed reaction mixture was dried over sodium sulfate and concentrated on a rotary evaporator to yield 13.18 grams of a dark liquid. It is determined by NMR spectroscopy that N
-(1,3-dioxolan-2-ylmethyl)
It was identified as -N-(2-propenyl)-2,2-dichloroacetamide.

Synthetic methods for specific compounds of the invention have been illustrated in some detail by the Examples above. It is understood, however, that any compound considered to be within the scope of the invention can be readily made by one skilled in the art by varying the selection of starting materials and by varying the techniques described above or other suitable techniques. .

Compounds produced as described in Example 1 and other compounds within the scope of the invention include:
It is useful in mitigating phytotoxic damage caused by active herbicides to growing crops, especially corn. These active herbicides, which tend to phytotoxically damage corn when used in herbicidally effective amounts against weeds growing between corn crops, are S-alkylthiocarpamate-type herbicides or chloroform herbicides. Acetanilide-type herbicides, especially the former. Good examples of some S-alkylthiocarbamate-type herbicides are S-ethyldiethylthiocarbamate, S-
These are ethyl diisobutyl thiocarbamate, S-ethyl dipropyl thiocarbamate, and S-propyl dipropyl thiocarbamate. on the other hand,
2-chloro-2',6'-diethyl-N-(methoxymethyl)acetanilide, 2-chloro-N-isopropylacetanilide, 2-chloro-N,N-diallylacetamide, N-chloroacetyl-N ―
(2,6-diethylphenyl)glycine ethyl ester, 2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide, and 2-chloro-2' ，
3'-Dimethyl-N-(methoxymethyl)acetanilide is a good example of some chloroacetanilide-type herbicides.

These S-alkylthiocarbamate herbicides or chloroacetanilide herbicides are typically incorporated into the soil or growing medium before sowing the crop. This technology is commonly referred to as "preplant incorporation." These detoxifying compounds of the invention can be mixed separately into the soil, but are preferably treated with or mixed with S-alkylthiocarbamate herbicides or chloroacetanilide herbicides. Used as an antidote. In either case, a sufficient amount of the detoxifying compound of the present invention is present such that the weight ratio of herbicide to compound of the present invention is within the range of 18:1 to 6:1; Of course, a herbicidally effective amount is required, which can vary over a wide range depending on the weed species. Typically, the amount of herbicide used ranges from 0.56 kg per hectare (0.5 lbs per acre) or less to 11.2 kg per hectare (10 lbs per acre) or more.

It is also understood that mixtures of S-alkylthiocarbamate herbicides and chloroacetanilide herbicides and mixtures of compounds of the invention may be used. Additionally, the herbicide and detoxifying compound formulations of the present invention can contain other agronomically desirable adjuvants. These adjuvants may include inert carriers, herbicides other than S-alkylthiocarbamates or chloroacetanilides, or other commonly used agricultural compounds such as insecticides, stabilizers, fertilizers, soil life extenders, etc. It is something.

The compounds of the invention, whether used alone or as herbicidal antidotes mixed with herbicides or as described above or treated with other substances, can be used as powders. , granules, moistened powders, solutions, suspensions, mist, emulsions, dispersions,
etc. can be applied to the soil by techniques known in the art.

Example 2 below describes the effects of phytotoxic damage caused by a commercially available herbicide, namely S-ethyldipropylthiocarbamate (commonly referred to as EPTC).
Figure 2 illustrates the detoxifying effects exhibited by these compounds of the present invention in protecting Funk's G-4288 hybrid field corn.

Example 2 (a) Pulverized sandy loam topsoil that passes through a 0.475 cm mesh sieve and coarse-grained washed cement sand are mixed in a weight ratio of 1 part sand to 3 parts soil, and the mixture is The steam was sterilized using the Pasteur method to kill all plants, pathogenic microorganisms, and natural weed species.

A soil mixture sterilized by the Pasteur sterilization method was filled into a sallow container, commonly called a "flats," to within 0.95 cm from the top of the container. The soil is leveled but not compacted. The container was then passed under an atomizer equipped with a fixed fan nozzle.
This fan nozzle is suspended on a movable belt with speed adjustment. The fan nozzle operated with an air pressure of approximately 2,800 grams per square centimeter and sprayed 25 milliliters of distilled water in 4.6 seconds. The spray had a spray profile with a width of 45.7 cm at 25.4 cm above the soil surface. The speed of the belt was adjusted to move 76.2 centimeters per revolution in 8.3 seconds. These soil test vessels passed under the nozzle in less than 4.6 seconds. The sprayed area was 0.63 square meters. The volume of liquid injected corresponded to 400 liters per hectare and 0.7029 grams of 100 percent active test compound per 0.63 square meters applied at a rate of 11.2 kilograms of active test compound per hectare.

S-alkylthiocarbamate i.e.
The carrier solvent used for EPTC and the specific detoxifying compound was a mixed solvent of acetone, methanol, and dimethyl formamide in a volume ratio of 90:8:2, respectively. After spraying the test container with the test compound or mixture of compounds, the container is immediately transferred to a clean plastic bag, the lid is closed, and the contents are thoroughly mixed by shaking the plastic bag by hand; The contents were then transferred to the original test container. The soil is then leveled, compacted, and Funk' S
G-4288 Hybrid Field Corn was sown and the soil mixture was covered with a 2.54 cm layer of Pasteur sterilized and screened sand. The treated flats were then transferred to a plant growth room.
There, the water needed for growth was lightly sown overhead onto these flats. The grow room was illuminated with an average light intensity of 27,000 lumens per square meter at the growth level.
The growth room was maintained at 29°C to 30°C during the 16-hour photoperiod and 20°C to 23°C at night.
was maintained. The relative humidity in the grow room averaged 50 to 55 percent when less than one-third full.

These treatment flats were allowed to grow and damage, if any, to the corn was determined by visual inspection periodically thereafter. Lesions were noted as stunted growth and/or hormonal abnormalities compared to untreated subjects.

This hormonal damage manifests as abnormal growth of the stem tip. The reason for this is that the leaves do not spread and develop from the growing bud. As the apex continues to grow, the secondary apex tissue becomes dense and abnormal until a break occurs in the surrounding leaf tissue. Hormone damage can occur either at the initial sowing stage when high concentrations of S-alkylthiocarbamate are applied, or at later growth stages when the herbicide is at lower concentrations. This abnormality does not appear until the developing stem tip is above the soil line or begins to branch and form female flowers. Hormone damage can also weaken the plant's root system, causing the entire plant to collapse under its own weight.

(b) EPTC (S-Ethyldipropylthiocarbamate) applied at a rate of 6.72 kg per hectare by Preplant Inc. as mentioned in paragraph (a) without the addition of compounds with detoxifying effect; , as mentioned above, the corn showed 90 percent damage. This means that the 14th, 25th, 28th and
Manifested by stunted growth and hormonal abnormalities after 42 days. Additionally, after 42 days, the erosion had also spread and deepened the damage to the corn crop.

(c) EPTC at a rate of 6.72 kg/ha and N-(1,3-dioxolane-2
-ylmethyl)-N-(2-propenyl)-
2,2-dichloroacetamide (produced as described in Example 1) at a rate of 1.12 kg/ha, i.e.
When applied by Preplant Inc. as described in paragraph (a) in a ratio of 1 part by weight of detoxifying compound to 6 parts by weight of EPTC, the corn herd remains healthy and normal after 42 days. , and showed no signs of stunting or hormonal abnormalities.

Although this invention has been described in considerable detail with respect to specific illustrative embodiments thereof, it is not intended that the invention be limited thereto;
The only intention is to be limited by the scope of the claims appended hereto.

Claims (1)

[Claims] A compound represented by the following formula: Here, R is 2-propenyl. 2 S-ethyl diethyl thiocarbamate, S-
a herbicidally effective amount of an S-alkylthiocarbamate herbicide selected from the group consisting of ethyl diisobutyl thiocarbamate, S-ethyl dipropyl thiocarbamate, and S-propyl dipropyl thiocarbamate; A herbicidal composition containing a compound represented by the following formula: Here, R is 2-propenyl. cubic formula (where R is 2-propenyl and R ⁵ and R ⁶ are alkyl having up to 4 carbon atoms)
reacting a substituted N-(2,2-dialkoxyethyl)amine with at least an equimolar amount of dichloroacetyl chloride in an inert organic solvent and in the presence of an acid acceptor to form a diacetal of the formula: and reacting this diacetal with at least an equimolar amount of ethylene glycol under anhydrous conditions and in the presence of an acid catalyst: Here, R is 2-propenyl.