JPS5984852A - Novel chloroacetanilide derivative and herbicide for paddy field - Google Patents

Abstract

NEW MATERIAL:A compound shown by the formula I (R and R' are methyl, ethyl, or isopropyl). EXAMPLE:2',6'-Diethyl-N-[2'-(2-butynyloxy)-ethyl]-2-chloroacetanilide. USE:A herbicide for paddy fields. Showing strong effect on Echinochloa crus-galli, extremely harmful weed, annual and perennial weeds, by application into water especially before germination or immediately after germination of weeds in cultivation of paddy rice plants, having almost no influence on rice plants. PROCESS:An N-substituted 2,6-dialkylaniline shown by the formula II is reacted with a chloroactylating agent, especially chloroacetic anhydride or halide, to give a compound shown by the formula I .

Description

[Detailed description of the invention] Concerning paddy field herbicides.

More specifically, the present invention provides 1', z' represented by the general formula (wherein, n and R' represent a methyl group, an ethyl group, or an isoprobyl group, which may be the same or different). -Dialkyl N (j/
The present invention relates to a paddy field herbicide containing -(2-ffnyloxy)ethyl-2-chloroaneptanilide (hereinafter referred to as the compound of the present invention) and the compound of the present invention as active ingredients.

The object of the present invention is to obtain this compound industrially and to provide a rice paddy herbicide that is extremely effective in rice cultivation compared to related compounds.

A large number of haloacetanilide derivatives having herbicidal activity are already known, and N-alkoxyethyl derivatives among them are also known in the literature. -3-
No. 31,060, special public Akihiro j4-3t, /l≠ issue, special public Akihiro tar! lI, No. 3.27, Special Publication 11th 3.3-, 23
, No. 372 is known.

Among these derivatives, the compounds actually used for paddy fields are 2/, l, /-diethyl-N-pro, JP.
xyethyl-chloroa heptanilide, λ′,
6'-Noethyl-N-ptoxymethyl--widely used with chloroacetanilide.

However, a serious drawback when applying these compounds in paddy fields is the fact that unless the paddy weeds are treated before and after germination, they will not be effective against weeds that have germinated and grown after the λ leaf stage. This means that after plowing, 2 to 3 leaves of fifi
In the current cultivation system in which $A seedlings are planted by machines, herbicides must be applied before and after rice planting, which is at the greatest risk of chemical damage, which is why there are many cases of chemical damage to paddy rice caused by these compounds.

Moreover, these compounds have strong activity against 49 grasses of the Phytophyllaceae family, such as crabgrass, barnyard grass, and foxtail grass, but they have the disadvantage that they are somewhat less effective against broad-leaved weeds, including yearlings, Mizono copae, Kikasigna, If the dosage is enough to completely kill annual weeds such as red pepper, Japanese azalea, Japanese aphrodisiac, Japanese horsetail, and other annual weeds, there is still a risk of chemical damage to paddy rice.

The present inventors conducted comparative research on many haloacetanilide derivatives and continued searching for further improved compounds for use in the rice fields.
Although the derivative has a strong inhibitory activity at low concentrations against Japanese grasshopper, a highly harmful weed in rice fields, it causes less chemical damage to rice than expected, and is effective against broad-leaved weeds. The inhibitory activity was also found to be stronger than expected.

That is, the present inventors investigated N-alkoxyethyl-710 acetanilide derivatives, particularly N-unsaturated alkoxyethyl substituted derivatives, and found that N-pro.
Contrary to the fact that the chemical damage to the sergyloxyethyl substituted product is strong, the terminal ψf of the
N-coptinyloxyethyl substituted product t of Fusugi with 75 methyl groups bonded to ff, N-alkenyloxyethyl substituted product or known N-propoxyethyl substituted product, N-
Compared to the proxyethyl-substituted product, it had very little phytotoxicity to rice and had strong inhibitory activity against paddy weeds.

This λ', t'-sialkyl-N-[λ'-(,2-butinyloxy)ethyl]-cochloroacetani 1-node conductor can control barnyard grass in paddy fields in extremely small amounts, but on the other hand, it is ioo times the lowest effective dose. It was confirmed that no chemical damage was caused to paddy rice even in small amounts.

Furthermore, it is possible to maintain sufficient activity against annual broad-leaved weeds for a long period of time at the lowest dosage for controlling barnyard grass.

In other words, the compound of the present invention has a strong effect on annual and perennial weeds, including the noxious weed, especially when applied to the water surface before or immediately after the germination of weeds in rice cultivation. is a selective herbicide that has almost no effect at any stage before or after transplanting, regardless of temperature.

The compounds of the present invention include (1), 2', j'-diederuN-[λ-(butynyloxy)ethyl]-λ-chloroacetanilide (e2) 2', t'-dimethyl-N-[: -2-(
butenyloxy)ethyl]---chloroacetanilito(3),2',t'-diisopropyl-N-(λ-
(Putinyloxy)ethyl]-λ-chloroacetanilide V) co'-methyl-2'-ethyl-N-(-2-(putinyloxy)ethyl)-2-chloroacetanilide.Among them, the compound (1) is Awarded.

The compounds of the invention can be prepared by unique methods.

According to the present invention, the chloroacetanilide d-conductor of general formula (13) is an N-substituted co, t-dialkylaniline represented by the general formula (wherein R and R' represent the above) with chloroacetyl aniline. It is produced by reaction with a chloroacetic acid anhydride or halide.

The compound represented by the general formula [■] is co, ip-dialkylaniline and λ-haloetasol t? React with cH ethylene oxide to form hydroxyalkyl chain -CHCHO
It is produced by introducing H and then etherifying the free OH group by the method described below.

(1) Etherification of /-halonobutine and free OH group by Williamson synthesis.

(I), 2-buten-7-ol and the OH group of I'S are etherified in a conventional manner under mild conditions in an acidic medium (eg Hα, H8O).

Of course, there are many other methods for producing the compounds of the present invention from λ,t-dialkylaniline, and the method is not limited to the above method.

Next, examples of synthesizing the compounds of the present invention including starting materials will be shown.

Example 1 (Compound No. 1) (a)2. A-diethylaniline blowfish yji (/M)
A mixture of ethylene chlorohydrin tig (/M) (7) was heated under reflux using a mantle heater for 7 hours. After cooling,
The reaction mixture was diluted with 200% ethyl ether,
The mixture was made alkaline with a 200% IJ solution (concentrated hydroxide). The ether layer was filtered, washed with water until neutral, and after drying, the ether was distilled off. When the residue is distilled under reduced pressure //J
-~//N boiling at 7℃/lffiwIHg (2
/ -hydroxyethyl)-,2,7-diethylaniline P/I was obtained.

(b) Formation eIJ as described in (a) in toluene 20d
60 sodium thihydride to 71 (0, OJM), 2.
017 (0, OJM) was added portionwise and the mixture was heated to reflux in an oil bath for 2 hours. After cooling, 7 g (0, θJ'M) of l-bromo-2-butyne was added, and the mixture was heated under reflux in an oil bath for 7 hours. After cooling, the reaction mixture was washed several times with jO- water. The organic layer was separated, dried, and toluene was distilled off under reduced pressure to give N-[λ'-(2-butenyloxy)-ether]-1.

0.1 g of crude product of 6-diethylaniline was obtained.

(C) Crude product 5i as described in (b) in benzene, 2Ome! 79 (0,0 g M) and pyridine l/l,
A solution of chloroacetyl chloride 1lji (0.0 gM) in benzene 10- was added portionwise to a solution of 9 (0.05M) and the mixture was stirred at room temperature for 1 hour. After the reaction was completed, the reaction mixture was washed several times with 30-mL water, the organic layer was taken, and after drying, benzene was distilled off under reduced pressure.

The residue was purified by silica dull column chromatography to give λ',t'-diethyl-N-(j'-(,2-butinyloxy)-ethyl]-2-chloroacetanilide 3.39
I got it.

Elemental analysis" 1812402Nlα, as) 11 1R (prepared) /GGa4-N-C) 10ri 0
(-0-)t4 NMRZol (jH,rn)
'AOO(-28,m)3.10(,2H,
m) 3.1.0 (,2)-1,S)j,J
-4(,2)-1,m),2. J-O(1-1, q
)/, 70 (JH,s) 7.20 (4)-1
, t) Refractive index (n o ) tj j J /Examples λ to Hiroshi Table 1 shows the physical property values of the compounds of the present invention synthesized in the same manner as in Example 1.

In order to use the compound of the present invention as a herbicide, it can be formulated into emulsions, wettable powders, powders, granules, etc. by blending various auxiliaries such as diluents, solvents, surfactants, etc. It is used by formulating it in the form of a drug.

It may be appropriate to add other herbicides to reduce spraying effort or to broaden the range of grass species that can be effectively controlled.

Although formulation examples of the compounds of the present invention will be described, the types and blending ratios of compounds and additives are not limited to these formulation examples, and can be varied within a wide range. Moreover, parts in the examples mean parts by weight.

Formulation example / Wettable powder (compound of the present invention) -0 parts, diatomaceous earth 3j parts, talcrylic 0 parts
1 part, 3 parts of sodium ligninsulfonate, and λ part of sodium dodecylbenzenesulfonate are mixed and ground to obtain a wettable powder.

Formulation Example λ Granules 5 parts of the compound of the present invention (1), 1 part of bentonite, 52.5 parts of talc, 1 part of Clay JJ, 1 part of sodium ligninsulfonate, 0.0 parts of sodium dodecylbenzenesulfonate. j′
The mixture is mixed and pulverized uniformly, water is added, the mixture is made into granules using an extrusion granulator, and the mixture is dried and sieved to form granules.

Formulation Example 3 Emulsion Compound G2) of the present invention is dissolved in 20 parts of xyl, 2 parts of fufu, 3 parts of polyoxyethylene alkyl ether, and alkylbenzene sulfonic acid calcium salt λt[[-Kl] to prepare an emulsion.

Next, the effects of the compounds of the present invention will be explained using test examples, and these results show that the compounds of the present invention have superior medicinal efficacy compared to commercially available similar compounds, and have reduced phytotoxicity to paddy rice. is clear.

Test example/ Novie control test in direct sowing by flooding//600
Paddy soil was filled in a 0 are Wagner pot, and after plowing, 20 paddy rice seeds (variety Nihonbare) and 10 wildflower seeds were sown. When paddy rice seeds and wild field seeds germinate, and when they reach 10 days/m period after sowing, the compound of the present invention is made into an emulsion according to Formulation Example 3, diluted with water to a predetermined amount, and uniformly spread on the water surface. processed. After sowing, the water was kept at a depth of 3 mm, and after chemical treatment, the weeding effect and the effect on rice were examined. Further, for testing purposes, similar tests were conducted on related compounds. The results are shown in Table 2.

Test example λ Soil treatment test for paddy fields 4 ■ 300
07. - Fill a Wagner pot with water and soil.
- Two-leaf stage (violet height approximately 10 cr) water lily young sprouts (variety: Nipponbare) were transplanted per pot. Soil containing 14 seeds of wild grass and major paddy weeds was uniformly inoculated within 2 cm of the surface layer, and then submerged with water at 3 cm. When the wild grass grew around the one-leaf stage, the compound of the present invention was added to Formulation Example 3. An emulsion prepared according to the method was diluted with a predetermined amount of water, spread uniformly, and stored at an average temperature of 2 g°C. Drug 1! cloth 21
A day later, the herbicidal effect and chemical damage to paddy rice were investigated. The results are shown in Table 3.

Evaluation of efficacy and evaluation of chemical damage to paddy rice was performed at the next step t.

j゛: Weed killing rate for untreated area ♂(17% or more)
(Rice damage rate to untreated area) ≠: Weed killing rate to untreated area 60-7 tachi (Rice damage rate to untreated area) 3: Weed killing rate to untreated area 1i-o-'-s tachi (untreated area) 2: Herbicidal rate of rice against the untreated area λO~32 (Rice damage rate of rice against the untreated area) /: Kill rate of rice against the untreated area 2Q- or less (Weed killing rate of rice against the untreated area with traps) Chemical damage rate) O: Completely the same as the untreated area

Claims (1)

[Claims] V) 2',6'-sialkyl represented by the general formula (wherein R1R1 represents an ethyl group, an ethyl group, or an isoprobyl group, which may be the same or different) -N-C12-(
Coptinyloxy)ethyl]-2-chloroacetanilide. -) λ', t'-dialkyl N-(λ' −(
,! A paddy field herbicide comprising -[y-dyloxy)ethyl]-cochloroacetanilide as an active ingredient and containing °C.