CH625510A5 - Process for the preparation of novel N,N-dimethyl-O-(imidazol-5-yl)carbamates and their use in insecticides - Google Patents

Description

The present invention relates to a process for the preparation of new N, N-dimethyI-0- [imidazol (5) yl] carbamate and its use in insecticides.

It is already known that N, N-dimethyl-0-pyrazoilylcarbamic acid esters, e.g. N, N-dimethyl-0- [3-methyl-1-phenyl-pyrazole (5) yl] -carbamic acid esters have insecticidal properties (cf. Swiss patent specification 282 655).

It has now been found that the new N, N-dimethyI - 0- [imidazol (5) yl] -carbamic acid esters of the formula

3rd

625510

CH,

Acid acceptor h3c- ^ Î + CI-co-N (CH3) 2 7 ^ *

CH-

CH,

The starting materials to be used are generally defined by the formulas (II) and (III). However, are preferably in formula (II)

R for straight-chain or branched alkyl with I to 5, for straight-chain or branched alkenyl with 2 to 4, or dialkylamino with 1 or 2 carbon atoms per alkyl radical, for phenyl, benzyl or for 2-phenylethyl,

R1 for hydrogen, straight-chain or branched alkyl or alkylthio with 1 to 3 and for alkenylthio with 2 to 4 carbon atoms and R2 for hydrogen, phenyl and straight-chain or branched alkyl with 1 to 4 carbon atoms.

The N, N-dimethyl-carbamic acid chloride (III) to be used as the starting material is known from the literature and, like the 5-hydroxyimidazole derivatives, can be prepared by known processes. In the case,

a) that R1 stands for alkylthio or alkenylthio, 2-thiohydantoin derivatives are reacted with alkyl or alkenyl halides in the presence of tertiary butoxide according to the following formula:

10th

15

20th

25th

0-C0-N {CH3) 2

CH,

#: • -

Shark tert-butylate m /

r »s-f |

OH

in which

R and R2 have the meaning given above, R 'represents alkyl or alkenyl and

Hai is halogen, preferably bromine or iodine, and b) that R1 is hydrogen, cyclizing a-isocyanocarboxamide derivatives in the presence of e.g. of potassium tert-butoxide according to the following formula:

40

45

N = C

R2-CH-C0-NHR

Potassium tert-butoxide

->

K '

©

in which

R and R2 have the meaning given above.

The following may be mentioned as examples of the 5-hydroxyimidazole derivatives (II):

5-Hydroxy-l- [methyl, ethyl, n-propyl, iso-propyl, n-butyl, sec-butyl, iso-butyl, n-pentyl, allyl, butene (2nd ) yl-, buten- (3) yl-, dimethylamine-, diethylamine-, phenyl-, benzyl- and (2-phenyIäthyl)] - imidazole, 5-hydroxy-l- [methyl- or ethyl-, n-propyl -, iso-propyl-, n-butyl-, sec.-butyl-, iso-butyl-, n-pentyl-, allyl-, butene (2) yl-, butene (3) yl-, dimethylamine-, diethyl- amine, phenyl, benzyl and (2-phenylethyl)] - 2-methylthio-imidazole, 5-hydroxy-l- [methyl, ethyl, n-propyl, iso-propyl, n-butyl, sec-butyl, iso-butyl, n-pentyl, allyl, butene (2) yl, butene (3) yl, dimethylamine, diethylamine, phe-

Sînyl-, benzyl- and (2-phenylethyl)] - 2-ethylthioimidazole, 5-hydroxy-l- [methyl-, ethyl-, n-propyl-, iso-propyl-, n-butyl-, sec.-butyl- , iso-butyl, n-pentyl, allyl, butene (2) yl, butene (3) yl, dimethylamine, diethylamine, phenyl, benzyl and (2-phenyl-ethyl)] - 2 -n-propylthioimidazole, 5-hydroxy-l- [methyl, ethyl, 60 n-propyl, iso-propyl, n-butyl, sec-butyl, iso-butyl, n-pen-tyl -, allyl-, butene (2) yl-, butene (3) yl-, dimethylamine, diethylamine *, phenyl-, benzyl- and (2-phenylethyl)] - 2-isopropyl-thioimidazole, 5-hydroxy-l- [ methyl, ethyl, n-propyl, iso-propyl, n-butyl, sec-butyl, iso-butyl, n-pentyl, allyl, 65 butene (2) yl, butene (3) yl-, dimethylamine-, diethylamine-, phenyl-, benzyl- and (2-phenylethyl)] - 2-allylthioimidazole, 5-hydroxy- l- [methyl-, ethyl-, n-propyl-, iso- propyl, n-butyl, sec.-butyl, iso-butyl, n-pentyl, allyl, butene (2) yl, butene (3) yl, dime

625510

4th

thylamine, diethylamine, phenyl, benzyl and (2-phenyl-ethyl)] - 2-butene (2) ylthioimidazole, 5-hydroxy-l- [methyl, ethyl, n-propyl, isopropyl, n-butyl, sec.-butyl, iso-butyl, n-pentyl, allyl, butene (2) yl, butene (3) yl, dimethylamine, diethylamine, phenyl, benzyl and (2-phenylethyl)] - 2-buten- (3) ythioimidazole and the corresponding ones in the 4-position of the imidazole ring by methyl, ethyl, n- and iso-propyl, n-, sec.- and iso- Butyl or phenyl substituted compounds.

The manufacturing process is carried out using solvents or diluents. Practically all inert organic solvents can be considered as such. These include in particular aliphatic and aromatic, optionally chlorinated, hydrocarbons, such as benzene, toluene, xylene, petrol, methylene chloride, chloroform, carbon tetrachloride, chlorobenzene, or ether, e.g. Diethyl and dibutyl ether, dioxane, tetrahydrofuran, also ketones, for example acetone, methyl ethyl, methyl isopropyl and methyl isobutyl ketone, and also nitriles, such as aceto and propionitrile.

All customary acid binders can be used as acid acceptors. Alkaiic carbonates and alcoholates, such as sodium and potassium carbonate, methylate or ethylate and potassium tert-butoxide, and also aliphatic, aromatic or heterocyclic amines, for example triethylamine, trimethylamine, dimethylaniline, dimethylbenzylamine and pyridine, have proven particularly useful.

The reaction temperature can be varied within a wide range. Generally one works between -20 and 60 ° C, preferably at -10 to 40 ° C.

The reaction is generally carried out at normal pressure.

To carry out the process, the starting materials are generally used in equimolar ratios. An excess of one or the other reaction component generally has no significant advantages. The N, N-dimethylcarbamoyl chloride is preferably added dropwise to the reaction solution of the 5-hydroxyimidazole component in the presence of an acid acceptor, without isolating it in the meantime, in such a way that the temperature of the reaction solution does not exceed 5 ° C. However, the salts of the 5-hydroxyimidazole component can also be used in the form of solutions. After the end of the reaction, the reaction mixture can be worked up as usual by shaking the reaction solution in succession with water and an organic solvent, such as methylene chloride. The organic phase is dried and the solvent is distilled off.

The compounds obtained according to the invention are obtained in part in the form of oils which cannot be distilled without decomposing, but by so-called «distillation», i.e. can be freed from the last volatile constituents by prolonged heating under reduced pressure to moderately elevated temperatures and cleaned in this way. The refractive index is used to characterize them. Some of the compounds are obtained in crystalline form with a sharp melting point.

As already mentioned several times, the new N, N-dimethyl-0- [imidazol (5) yl] -carbamic acid esters are characterized by an excellent insecticidal activity. Some of the compounds have an anti-development effect.

With good plant tolerance and favorable warm-blood toxicity, the active substances are suitable for combating animal pests, in particular insects, arachnids and nematodes, which occur in agriculture, in forests, in the protection of stored goods and materials, and in the hygiene sector. They are normally sensitive and resistant

Species as well as against all or individual stages of development. The pests mentioned above include:

From the order of the Isopoda e.g. Oniscus asellus, Ar-madillidium vulgare, Porcellio scaber.

5 From the order of the Diplopoda e.g. Blaniulus guttulatus.

From the order of the Chilopoda e.g. Geophilus carpo-phagus, Scutigera spec.

From the order of the Symphyla e.g. Scutigerella immaculata.

10 From the order of the Thysanura e.g. Lepisma saccharina.

From the order of the Collembola e.g. Onychiurus arma-

tus.

From the order of the Orthoptera e.g. Blatta orientalis, Periplaneta americana, Leucophaea maderae, Blattella ger-15 manica, Acheta domesticus, Gryllotalpa spp., Locusta migratoria migratorioides, Melanoplus differentialis, Schistocerca gregaria.

From the order of the Dermaptera e.g. Forficula auricu-Iaria.

20 From the order of the Isoptera e.g. Reticulitermes spp.

From the order of the anoplura e.g. Phylloxéra vastatrix, Pemphigus spp., Pediculus humanus corporis, Haematopinus spp., Linograthus spp.

From the order of the Maliophaga e.g. Trichodectes spp., 25 Damulinea spp.

From the order of the Thysanoptera e.g. Hercinothrips femoralis, Thrips tabaci.

From the order of the Heteroptera e.g. Eurygaster spp., Dysdercus intermedius, Piesma quadrata, Cimex Iectularius, 30Rhodnius prolixus, Triatoma spp.

From the order of the Homoptera e.g. Aleurodes brassi-cae, Bemisia tabaci, Trialeurodes vaporariorum, Aphis gossy-pii, Brevicoryne brassicae, Cryptomyzus ribis, Doralis fabae, 3J Doralis pomi, Eriosoma lanigerum, Hyalopterus arundinis, Macrosiphum avenae, Rhodumophiumo, myodon sppuli, Phuson sppuli, Ph. Empoasca spp., Euscelis bilobatus, Nepho-tettix cincticeps, Lecanium corni, Saissetia oleae, Laodelphax striatellus, Nilaparvata lugens, Aonidiella aurantii, Aspidio- ^ tus hederae, Pseudococcus spp. Psylla spp.

From the order of the Lepidoptera e.g. Pectinophora gossypiella, Bupalus piniarius, Cheimatobia brumata, Litho-colletis blancardella, Hyponomeuta padella, Plutella maculi-pennis, Malacosoma neustria, Euproctis chrysorrhoea, Lyman- <5 tria spp., Bucculatrix thocrnistisis, Ph ., Feltia spp., Earias insulana, Heliothis spp., Laphygma exigua, Mamestra brassicae, Panolis flammea, Prodenia litura, Spodoptera spp., Trichoplusia ni, Carpocapsa pomonella, Pieris spp., Chilo spp., Pyrausta nu-50ia kuehniella, Galleria mellonella, Cacoecia podana, Capua reticulana, Choristoneura fumiferana, Clysia ambiguella, Homona magnanima, Tortrix viridana.

From the order of the Coleoptera e.g. Anobium puncta-tum, Rhizopertha dominica, Bruchidius obtectus, Acantho-55 scelides obtectus, Hylotrupes bajulus, Agelastica alni, Leptino-tarsa decemlineata, Phaedon cochleariae, Orabrotica spp ., Sitophilus spp, Otiorrhynchus sulcatus, Cosmopolites sordidus, Ceuthorrhyn-60 chus assimilis, Hypera postica, Dermestes spp., Trogoderma spp., Anthrenus spp., Attagenus spp., Lyctus spp., Meligethes aeneuc., Ptinus, Ptinus, Ninus Gibbium psylloides, Tribolium spp., Tenebrio molitor, Agriotes spp., Conoderus spp., Melolontha melolontha, Amphimallon solstitialis, Coste-65 lytra zealandica.

From the order of the Hymenoptera e.g. Diprion spp., Hoplocampa spp., Lasius spp., Monomorium pharaonis,

Vespa spp.

From the order of the Diptera e.g. Aëdes spp., Anopheles spp., Culex spp., Drosophila melanogaster, Musca spp., Fannia spp., Calliphora erythrocephala, Lucilia spp., Chrysomyia spp., Cuterebra spp., Gastrophilus spp., Hyppobosca spp., Stomoxys Oestrus spp., Hypoderma spp., Tabanus spp., Tannia spp., Bibio hortulanus, Oscinella frit, Phorbia spp., Pegomya hyoscyami, Ceratitis capitata, Dacus oleae, Tipula paludosa.

From the order of the Siphonaptera e.g. Xenopsylla cheopis, Ceratophyllus spp.

From the order of the Arachnida e.g. Scorpio maurus, Latrodectus mactans.

From the order of the Acarina e.g. Acarus siro, Argas spp., Ornithodoros spp., Dermanyssus gallinae, Eriophyes ribis, Phyllocoptruta oleivora, Boophilus spp., Rhipicephalus spp., Amblyomma spp., Hyalomma spp., Ixodes spp., Psorop-tes spp.,. Sarcoptes spp., Tarsonemus spp., Bryobia praetiosa, Panonychus spp., Tetranychus spp.

Plant parasitic nematodes include Pratylen-chus spp., Radopholus similis, Ditylenchus dipsaci, Tylen-chulus semipenetrans, Heterodera spp., Meloidogyne spp., Aphelenchoides spp., Longidorus spp., Xiphinema spp., Tri-chodor.

The active ingredients can be converted into the customary formulations, such as solutions, emulsions, wettable powders, suspensions, powders, dusts, foams, pastes, soluble powders, granules, aerosols, suspension emulsion concentrates, seed powders, active ingredient-impregnated natural and synthetic substances , Fine encapsulation in polymeric substances and in coating compositions for seeds, also in formulations with fuel sets, such as smoking cartridges, cans, spirals, etc. as well as ULV cold and warm fog formulations.

These formulations can be prepared in a known manner, e.g. by mixing the active ingredients with extenders, that is to say liquid solvents, pressurized liquefied gases and / or solid carriers, if appropriate using surface-active agents, that is to say emulsifiers and / or dispersants and / or foam-generating agents. If water is used as an extender, e.g. organic solvents can also be used as auxiliary solvents. The following are essentially suitable as liquid solvents: aromatics, such as xylene, toluene, or alkylnaphthalenes, chlorinated aromatics or chlorinated aliphatic hydrocarbons, such as chlorobenzenes, chloroethylene or methylene chloride, aliphatic hydrocarbons, such as cyclohexane or paraffins, e.g. Petroleum fractions, alcohols, such as butanol or glycol, and their ethers and esters, ketones, such as acetone, methyl ethyl ketone, methyl isobutyl ketone or cyclohexanone, strongly polar solvents, such as dimethylformamide and dimethyl sulfoxide, and water; liquefied gaseous extenders or carriers mean liquids which are gaseous at normal temperature and pressure, e.g. Aerosol propellants, such as halogenated hydrocarbons and butane, propane, nitrogen and carbon dioxide; as solid carriers: natural rock powder, such as kaolins, clays, talc, chalk, quartz, atta-pulgite, montmorillonite or diatomaceous earth and synthetic rock meals, such as highly disperse silica, aluminum oxide and silicates; as solid carriers for granules: broken and fractionated natural rocks such as calcite, marble, pumice, sepiolite, dolomite as well as synthetic granules from inorganic and organic flours as well as granules from organic material such as sawdust, coconut shells, corn cobs and tobacco stalks; as emulsifying and / or foaming agents: nonionic and anionic emulsifiers, such as polyoxyethylene fatty acid esters, polyoxyethylene fatty alcohol ethers, e.g. Alkylaryl polyglycol ether,

5 625510

Alkyl sulfonates, alkyl sulfates, aryl sulfonates and protein hydrolysates; as a dispersant: e.g. Lignin, sulfite liquor and methyl cellulose.

Adhesives such as carb-5 oxymethyl cellulose, natural and synthetic polymers in the form of powders, granules or latices, such as gum arabic, polyvinyl alcohol and polyvinyl acetate, can be used in the formulations.

Dyes such as inorganic pigments, e.g. Iron oxide, titanium oxide, ferrocyan blue and organic dyes such as alizarin, azo metal phthalocyanine dyes and trace nutrients such as salts of iron, manganese, boron, copper, cobalt, molybdenum and zinc can be used.

The formulations generally contain between 0.1 and 95 percent by weight of active compound, preferably between 0.5 and 90%.

The new active compounds are usually used in the form of their commercially available formulations and / or the use forms prepared from these formulations.

The active substance content of the use forms prepared from the commercially available formulations can vary within wide ranges. The active substance concentration of the use forms can be from 0.0000001 to 100% by weight of active substance, preferably between 0.01 and 10% by weight.

The application is generally carried out in a customary manner adapted to the 23 application forms.

When used against hygiene pests and pests of stored products, the new active ingredients are distinguished by an excellent residual action on wood and clay and by a good stability to alkali on limed substrates.

30th

Example A Myzus test (contact effect)

Solvent: 3 parts by weight of dimethylformamide 35. Emulsifier: 1 part by weight of alkylaryl polyglycol ether

To produce a suitable preparation of active compound, 1 part by weight of active compound is mixed with the stated amount of solvent and the stated amount of emulsifier, and the concentrate is diluted with water to the desired concentration.

Cabbage plants (Brassica oleracea) which are heavily infested with peach aphids (Myzus persicae) are sprayed to runoff point with the preparation of active compound.

After the specified times, the kill is determined in%. 100% means that all aphids have been killed; 0% means that no aphids have been killed.

Active substances, active substance concentrations, evaluation times and results are shown in the table below:

625510

TABLE 1 (plant-damaging insects)

Myzus test

Active ingredients

CH

3rd

in 0

O

(known)

3> -c-n (ch,)

3 2

3rd

ch-0 '

i 0-C-N (CH,) o CH3 3 2

n_

CH.S / I ^

^ iï-Lo-c-: 6h,

n (ch3) 2

ch3s ch3s n-ph3

41 0

n ^ o-c-n (ch3) 2

N C3H7iso

-4 | ? , N

^ o-c-n (ch3) 2

Ö o

(O CS

0.1 0.01

0.1 0.01

0.1 0.01

0.1 0.01

0.1 0.01

98 0

100 99

100 85

100 90

100 80

TABLE 1 (continued)

00

mêSH

3.C -

u CO

<00 G.

Active ingredients

ch

0 S, N

w-, 0-c- (ch,) o Ö3H7iso 3 2

15

2och3s

<

ch3

s, \

0-c-n (ch3) 2

C3H7-iso

25th

f

30 n ~ \

ch-0

tt o-c-n (ch3) 2

ch2-ch = ch2

35

ch3s ch,

- <ft;

i

40

• N-I

ch2-ch = ch2

k0-c-n (ch3) 2

chr

45

tt 0

1 o-c-n (ch3) 2

C4H9-iso or

^ 4

O

co G "

£ «£ 8.5

0.1

0.01

0.1 0.01

0.1

0.01

0.1

0.01

0.1 0.01

60

§> è8H § e -: 2-aJ5 5 2 p

<M C

100 100

100 99

100 100

100 100

100 100

50

CH,

CHP = CH-CH2-S-fI 0

0.1

<k

0-e-N (CH5) 2o.01

Ö

0

i 0-c-n (ch,) «C3H7-iso

0.1 0.01

0.1 0.01

100

99

100

95

Example B Doralis test (systemic effect)

55 Solvent: 3 parts by weight of dimethylformamide emulsifier: 1 part by weight of alkylaryl polyglycol ether To produce a suitable preparation of active compound, 1 part by weight of active compound is mixed with the stated amount of solvent and the stated amount of 0 emulsifier and the concentrate is diluted with water to the desired concentration.

Bean plants (Vicia faba), which are heavily infested with black bean louse (Doralis fabae), are watered on with the active substance preparation, so that the active substance -65 preparation penetrates into the soil without wetting the leaves of the bean plants. The active ingredient is taken up from the soil by the bean plants and thus reaches the infected leaves.

7

625510

After the specified times, the kill in%

certainly. 100% means that all aphids are killed.

have been tested; 0% means that no aphids have been killed.

Active substances, active substance concentrations, evaluation times 5 active substances and results are shown in the table below:

TABLE 2 (continued)

c o

$ 3

TABLE 2 (plant-damaging insects) Doralis test (systemic effect)

Active ingredients m ii 0

- o-8-n (ch3) 2

(known)

n- / 3rd

(1 0 VVc-

ch-

c-n (ch3) 2

ch, s-3 xn-

Vt ch, _7 '

0 »

0-c-n (ch3) 2

n (ch3) 2

CH3S "V

k_ / ch3

0

ii ch30-c-n (ch3) 2

G

O

C / 3 CO

£ 8.5

0.1 0.01

0.1 0.01

0.1 0.01

0.1 0.1

Ä

co c ^

n e? y ^ ä u 2 <, 00 ö

100

100 100

100 100

100 100

SP

oo e5-.®

c

3.Ö- *: 3-o-g

<WJ c io |

ch,

ch3s

0 h

15

20th

Ii ijjl0-c-n (ch3) 2

ch2-ch = ch2

0.1 0.01

100 100

Example C

Limit concentration test / root systemic effect

Test insect: Phaedon cochleariae larvae. Solvent: 3 parts by weight of acetone emulsifier: 1 part by weight of alkylaryl polyglycol ether.

The active ingredient preparation is intimately mixed with the soil. The concentration of the active ingredient in the preparation is practically irrelevant, the only decisive factor is the amount of active ingredient per unit volume of soil, which is given in ppm (= mg / I). The treated soil is filled into pots and planted with cabbage (Brassica oleracea). The active ingredient can be taken up from the soil by the plant roots and transported to the leaves.

To prove the root systemic effect, only the leaves are populated with the above-mentioned test animals after 7 days. After a further 2 days, the evaluation is carried out by counting or estimating the dead animals. The root systemic effect of the active ingredient is derived from the number of killings. It is 100% if all test 45 animals have been killed and 0% if as many test insects are still alive as in the untreated control.

Active ingredients, application rates and results are shown in Table 3 below:

50

ch3s ch,

- [t s i "~ ^ 0-c-n (ch,) o

'H -ion d-

C3Hy — iso

0.1 0.01

100 100

55

MI

o-c-n (ch3) 2 ch2-ch = ch2

0.1 0.01

100 95

60

65

625510

8th

TABLE 3 Root systemic activity of Phaedon cochleariae larvae

Active substance (constitution)

Degree of killing in% of an active ingredient concentration of 50 ppm

TABLE 4 Root systemic effects of Myzus persicae

Active substance (constitution)

io

CH3-C- CH 0

N c-0-C-N (CH,) p \ N / 5 *

0

(known)

/ irch3

ch3-s-ti °,

• 0-C-N (CH,) 2 CH3

100

Degree of killing in% with an active ingredient concentration of 10 ppm ch, -ç — çh ç

3 ftnn £ -0-c-n (ch3) 2

15

O

(known)

ch,

20th

ch-

1 + Q?

tS30-C-N (CH3) 2

100

25th

ch-

'0

II

Example D

Limit concentration test / root systemic effect

Test insect: Myzus persicae

Solvent: 3 parts by weight of acetone

Emulsifier: 1 part by weight of alkylaryl polyglycol ether

To produce a suitable preparation of active compound, 1 part by weight of active compound is mixed with the stated amount of solvent, the stated amount of emulsifier is added and the concentrate is diluted with water to the desired concentration.

The active ingredient preparation is intimately mixed with the soil. The concentration of the active ingredient in the preparation is practically irrelevant, the only decisive factor is the amount of active ingredient per unit volume of soil, which is given in ppm (= mg / 1). The treated soil is filled into pots and planted with cabbage (Brassica oleracea). The active ingredient can be taken up from the soil by the plant roots and transported to the leaves.

To demonstrate the root systemic effect, only the leaves are populated with the test animals mentioned above after 7 days. After a further 2 days, the evaluation is carried out by counting or estimating the dead animals. The root systemic effect of the active ingredient is derived from the number of killings. It is 100% when all test animals have been killed and 0% when as many test insects are still alive as in the untreated control.

Active ingredients, application rates and results are shown in Table 4 below:

ch3-s "uo-c-n (ch,) 2

d_3HZ4so 3 2

100

ch3-s- <

35

^ CH3

■ w 0

100

n-fl J0

CHo = CH-CH0-S-C Ii »

«L2 ^" W112 ch

100

0-C-N (CH3) 2

n-

«4

o »

, o-c-n (ch3) 2

C3Hy-iso

100

50

N-3

<"1

55

XN-

i ch, 3

0 h

O-c-n (ch3) 2

100

ch2-ch = ch2

60

65

9

625510

Manufacturing examples

example 1

a)

ch

V

ch.

3? - ^ oh ch,

. A solution of 14.4 g (0.1 mol) 1.4 is added dropwise to a suspension of 12.4 g (0.11 mol) potassium tert-butoxide in 100 ml tetrahydrofuran with stirring at -10 ° C -Dimethyl - 2-thiohydantoin (production see T. Wieland, R. Müller, E. Niemann, L. Birkhofer, A. Schöberl, A. Wagner and H. Söll in Houben-Weyl-Müller, methods of the organic chemistry volume 11/2, Georg Thieme Verlag, Stuttgart 1958, p. 267 ff) and then 14.2 g (0.1 mol) of methyl iodide and allowed to stir for 1 hour at -10 ° C. The 5-hydroxy-2-methylthio-1,4-dimethylimidazole formed is not isolated from the solution, but is immediately processed further.

b)

0-c0-n (ch3) 2

10th

A - 10 ° C cold solution of 0.1 mol of 5-hydroxy-2-methylthio-l, 4-dimethylimidazole in tetrahydrofuran prepared under 1 a) is stirred with 12.4 g (0.11 mol) of potassium tert. - Butylate added and stirred at 0 ° C for 30 minutes. A solution of 10.85 g (0.1 mol) of N, N-dimethyIcarbaminoyl chloride in 25 ml of tetrahydrofuran is then added dropwise in such a way that the temperature does not exceed + 5 ° C.

After stirring for one hour at about 5 ° C, the solvent is evaporated at 40 ° C on a rotary evaporator in a vacuum. The residue is shaken with 50 ml of water, extracted twice with 75 ml of methylene chloride, the combined organic phases are dried over magnesium sulfate and the solvent is distilled off in vacuo. 16 g (70% of theory) of N, N-dimethyl-0- [1,4-dimethyl-2-methyl-25thio-imidazole (5) yl] -carbamic acid ester are obtained in the form of a yellow oil with the refractive index nD24: 1 , 5258.

The compounds of the formula

30th

r

35

, d-co-n (ch,) 9

R * *

(i)

getting produced:

40

Example No.

R

R1

R2

Physical. Data (refractive index; melting point ° C)

Yield (% of theory)

3rd

ch3s-

-ch3

n 22-nD.

1.5135

82

2nd

-ch2 = ch-ch2

ch3s-

n 21-nD.

1.5600

68

4th

-ch3

ch3s-

-CaH7-iso n 22 ■

nD.

1.5420

76

5

■ ©

ch3s-

-H

n 24-

nD.

1.5200

71

6

-chs chas-

-H

n 2e-

"D.

1.5180

65

7

-N (CH3) 2

ch3s-

-CHs

117

49

8th

-cjh ^ iso

CH, S-

-CH3

nD26:

1.5110

84

9

-CH2-CH = CH2

CHsS-

-CHs nD25:

1.5210

96

10th

-ch3

ch2 = ch-ch2s-

-CHs nD25:

1.5299

86

625510

10th

a)

Example 11

ch,

ok ch,

A solution of 6.72 g (60 mmol) of N-methyl-a is added dropwise to a suspension of 6.8 g (60 mmol) of potassium tert-butoxide in 200 ml of tetrahydrofuran at 5 ° C. in the course of 10 minutes -isocyano-propionic acid amide (for production see H. Henecka and P. Kurtz in Houben-Weyl-Mül-ler, Methods of Organic Chemistry, Volume 8, Georg Thieme Verlag, Stuttgart 1952, p. 667 ff) and then allow 15 minutes Stir 5 ° C. The potassium salt of 5-hydroxy-1,4-dimethylimidazole is not isolated, but is immediately reacted further.

b)

ce ch,

ch,

o-co-n (ch3) 2

A solution of 6.5 g (60 mmol) of N, N-dimethylcarbamoyl chloride was added dropwise to a solution of 10 60 mmol of 5-hydroxy-1,4-dimethylimidazole potassium salt in tetrahydrofuran prepared at approx. 0 ° C. under IIa) that the temperature does not exceed 5 ° C. After stirring for two hours at 0-5 ° C, the tetrahydrofuran is removed in vacuo at 40 ° C on a rotary evaporator. The residue is shaken with 50 ml of water, extracted twice with 75 ml of methylene chloride and the combined organic phases are dried over magnesium sulfate. The solvent is distilled off in vacuo and 8 g (73% of theory) of 20 N, N-dimethyl-O- [1,4-dimethylimidazole (5) yl] -carbamic acid ester are obtained as a light yellow oil which is left to stand after a few days crystallized at room temperature (melting point 68-70 ° C).

Analogously to Example 11, the compounds of the formula

25th

30th

(I)

-co-n (ch3) 2

getting produced:

Example No.

R

Rl

R2

Physical. Data (refractive index; melting point ° C)

Yield (% of theory)

12th

-ch3

H-

-h nD24: 1.4865

86

13

-c3h7 — ISO

H-

-h nD25: 1.4982

97

14

-CsJi7-ÌSO

H-

-ch3

nD25: 1.4869

71

15

-ch2-ch = ch2

H-

-ch3

nD20: 1.4991

86

16

-C4H9-iso h-

-cha nD20: 1.4841

90

17th

-ch2 ^>

H-

-ch «

120-125

88

Claims (3)

625510 2nd PATENT CLAIMS 1. Process for the preparation of new N, N-dimethyl - 0- [imidazoI- (5) -yl] -carbamic acid esters of the formula -r2 (I) (I) 0-c0-n (ch3) 2 r 0-c0-n (ch5) 2 in which R represents alkyl, dialkylamino, alkenyl or aralkyl with 1 to 4 Carbon atoms in the alkyl part or for aryl, R1 stands for hydrogen, alkyl, alkylthio or alkenylthio, while R2 represents hydrogen, phenyl, alkyl or alkenyl, characterized in that 5-hydroxyimidazole derivatives of the formula 10th 15 in which R represents alkyl, dialkylamino, alkenyl or aralkyl with 1 to 4 carbon atoms in the alkyl part or for aryl, R1 stands for hydrogen, alkyl, alkylthio or alkenylthio, while R2 represents hydrogen, phenyl, alkyl or alkenyl, have an excellent insecticidal effect. Furthermore, it was found that the new N, N-dimethyl - 0- [imidazol (5) yl] -carbamic acid esters of the formula (I) according to the invention are obtained if 5-hydroxyimide-azole derivatives of the formula 20th r1-fif ö » oh r as such or in the form of their alkali metal, alkaline earth metal or ammonium salts with N, N-dimethylcarbamic acid chloride of the formula Cl-CO-N (CHa) 2 (III) in the presence of a solvent or diluent. 2. The method according to claim 1, characterized in that the compound of formula II, which is present as a free base, is reacted with compounds of formula III in the presence of an acid acceptor. 3. Use of new N, N-dimethyl-0- [imidazol- (5) yl] -carbamic acid esters of the formula (II) in which R, R1 and R2, which have the meaning given above, as such, optionally in the presence of an acid acceptor, 30 or in the form of their alkali metal, alkaline earth metal or ammonium salts with N, N-dimethylcarbamic acid chloride of the formula Cl-CO-N (CH3) 2 (III) 1T ^ o-co-n (ch3) 2 r (i) 35 in the presence of a solvent or diluent. Surprisingly, the new N, N-dimethyl - 0- [imidazol (5) yl] -carbamic acid esters (I) show a better insecticidal action than the previously known N, N-dimethyl-0- [3-me-40thyl-l-phenylpyrazole (5) yl] -carbamic acid esters of analogous constitution and the same direction of action. The fabrics mentioned are a real asset to the technology. If, for example, 1,2,4-trimethyl-5-hydroxyimidazole and N, N-dimethylcarbamic acid chloride are used as starting materials, the course of the reaction can be represented by the following formula: in which R represents alkyl, dialkylamino, alkenyl or aralkyl with 1 to 4 Carbon atoms in the alkyl part or for aryl, R1 stands for hydrogen, alkyl, alkylthio or alkenylthio, while R2 represents hydrogen, phenyl, alkyl or alkenyl, as at least one active component in insecticidal compositions. 50 55