DE4206767A1 - Pesticide compsn. contg. (poly)thiophene deriv. - Google Patents

Abstract

Pesticide compsns. contain thiophene or polythiophene derivs. of formula (I) and inert additives: R1-R3 = H or 1-18C alkylthio; n = 0-5; R3 gps. may be different if n is more than 1. Cpds. (I) are new provided that: (i) R1-R3 are not all H; and (ii) R1 is not H when R2 = MeS and n = 0. More specifically R1-R3 = H or 1-8C alkylthio (esp. MeS); n = 0-4 (esp. 0-3).

Description

The present invention relates to thiophenes and polythio phene of formula I.

in which the substituents and the index have the following meaning:
R ¹ , R ² and R ³ independently of one another are hydrogen and C ₁ -C ₁₈ -alkylthio,
n
0, 1, 2, 3, 4 or 5, where the radicals R ³ can be different if the value of n is <1,
where R ¹ , R ² and R ^{3 are} not simultaneously hydrogen and where R ^{1 is} not hydrogen if R ^{2 is} methylthio and n is 0.

Furthermore, the invention relates to methods for the manufacture position of these compounds, containing at least agents a thiophene or polythiophene of the formula I ′

in which the substituents and the index have the following meaning:
R ¹ , R ² and R ³ independently of one another are hydrogen and C ₁ -C ₁₈ -alkylthio,
n
0, 1, 2, 3, 4 or 5, where the radicals R ³ can be different if the value of n is <1,
and inert additives and pest control methods.

It is known that certain bis and terthienylver bindings are nematicidal (US-A 30 50 442; WO-A 86/0 05 949; Tetrahedron 44, 2403-2413 (1988)). Furthermore were such compounds with herbicidal properties described (EP-A 3 53 667).

The invention was new, suitable for pest control Active substances as a task.

Accordingly, the thiophenes and poly thiophene found. In addition, processes for their manufacture position, compositions containing them and their use for Pest control found.

The connections are different according to themselves Literature known methods accessible. Essentially The following general procedures are used:

A: Halogenation of thiophene or polythiophenes (Gronowitz et al., Acta Chem. Scand., 13, 1045 (1959); MacEachern et al., Tetrahedron 44 (9), 2403 (1988); Taylor et al., J. Org. Chem., 50, 1002 (1985).

Starting from an unsubstituted or substituted Thiophene will introduce the halogen substituent in generally according to the method described by Taylor et al. described method (P. 1003) in the presence of N-bromosuccinimide or N-chlorine succinimide performed.

The reaction temperatures are usually from 0 ° C to 50 ° C, preferably 10 ° C to 40 ° C.  

The halogenating agents can generally be equimolar or used in excess.

Halogenated Koh are particularly suitable as solvents Hydrogen oils such as methylene chloride and tetrachloroethane so like protic polar solvents like acetic acid.

Mixtures of the solvents mentioned can also be used be det.

B: Production and implementation of the Grignard connections (MacEachern et al., Tetrahedron 44 (9), 2403 (1988); Jayasuriya et al., Heterocycles 24 (10), 2901 (1986))

Starting from a halogenated thiophene, the manufacturer development and implementation of the Grignard connection advantageous according that of MacEachern et al. described method leads.

The reaction temperatures are usually from 10 ° C to 60 ° C, preferably 20 ° C to 50 ° C.

The amount of magnesium shavings or magnesium grits' is in generally at least equimolar, commonly used one in excess, however.

Suitable solvents are in particular ethers such as diethyl ether, diisopropyl ether, tert-butyl methyl ether and dioxane, particularly preferably diethyl ether and tert-butyl methyl ether.

Mixtures of the solvents mentioned can also be used be det.

With regard to the implementation speed and the Aus It can be advantageous to loot the reaction mixture Add catalyst.

In this sense, catalysts like
Pd (dppf) Cl ₂ (dppf = 1,1′-bis (diphenylphosphino) ferrocene) and
Ni (dppp) Cl ₂ (dppp = 1,3-bis (diphenylphosphino) propane) use.

The further implementation of the Grignard compound thus obtained with a halogen thiophene can be done directly (in situ) or after previous isolation of the intermediate stage.

C: Reaction of the halothiophenes with disulfides (Diplomar at University of Stuttgart 1990, F. Würthner)

The conversion of a halogenated thiophene with a disul fid generally occurs at low temperatures in egg an aprotic solvent in the presence of an alkali tall organyls.

The reaction temperatures are usually around -100 ° C to 0 ° C, preferably -80 ° C to -40 ° C.

In general, organometallic ones can be used as alkali metal organyls Compounds, especially alkali metal alkyls such as methyl lithium, butyllithium and phenyllithium.

The alkali metal organyls are generally in excess from 10 to 100 mol%, preferably 10 to 50 mol%, based to be used on the halogen thiophene.

Aliphatic hydrocarbons such as Pentane, hexane, cyclohexane and petroleum ether, ethers such as Di ethyl ether, diisopropyl ether, tert-butyl methyl ether, dioxane and tetrahydrofuran, particularly preferably ether use.

Mixtures of the solvents mentioned can also be used be det.

The starting materials are generally at least in an equimo laren amount implemented together. With regard to a he Increasing the yield, however, it may be advantageous to Di sulfide in an excess of 10 mol% to 100 mol% preferably 10 mol% to 50 mol%, in particular 10 mol% to 20 mol% based on the amount of halogen thiophene put.

With regard to their biological activity, preference is given to compounds I ′ in which the substituents and the index have the following meaning:
R ¹ , R ² and R ^{3 are} independently hydrogen;
C ₁ -C ₁₈ alkylthio, especially C ₁ -C ₈ alkylthio such as methylthio, ethylthio, propylthio, 1-methylethylthio, butylthio, 1-methylpropylthio, 2-methylpropylthio, 1,1-dimethylethylthio, pentylthio, 1-methylbutylthio, 2-methylbutylthio, 3-methylbutylthio, 2,2-dimethylpropylthio, 1-ethylpropylthio, hexylthio, 1,1-dimethylpropylthio, 1,2-dimethylpropylthio, 1-methylpentylthio, 2-methylpentylthio, 3-methylpentylthio, 4- Methylpentylthio, 1,1-dimethylbutylthio, 1,2-dimethylbutylthio, 1,3-dimethylbutylthio, 2,2-dimethylbutylthio, 2,3-dimethylbutylthio, 3,3-dimethylbutylthio, 1-ethylbutylthio, 2-ethylbutylthio, 1, 1,2-tri methylpropylthio, 1,2,2-trimethylpropylthio, 1-ethyl-1-methylpropylthio and 1-ethyl-2-methylpropylthio, as well as unbranched and branched heptylthio, octylthio, nonylthio, decylthio, undecylthio, dodecylthio, tridecylthio, Tetradecylthio, pentadecylthio, hexadecylthio, hepta decylthio and octadecylthio, preferably the C ₁ -C ₆ -alkylthio radicals mentioned, in particular di e called C ₁ -C ₄ alkyl thio
n
0, 1, 2, 3, 4 or 5, it being possible for the radicals R ^{3 to be} different if the value of n is <1.

Particular preference is given to thiophenes and polythiophenes of the formula I ′ in which the substituents and the index have the following meaning:
R ¹ , R ² and R ³ independently of one another
Hydrogen, C ₁ -C ₈ alkylthio as mentioned above in general and in particular and
n
0, 1, 2, 3 or 4, it being possible for the radicals R ^{3 to be} different if the value of n is <1.

In addition, thiophenes and polythiophenes of the formula I ′ are particularly preferred in which the substituents and the index have the following meaning:
R ¹ , R ² and R ³ independently of one another
Hydrogen, C ₁ -C ₃ alkylthio as mentioned above in general and in particular and
n
0, 1, 2, 3 or 4, it being possible for the radicals R ^{3 to be} different if the value of n is <1.

Of biological interest are also thiophenes and polythiophenes of the formula I ′, in which the substituents and the index have the following meaning:
R ¹ , R ² and R ³ independently of one another are hydrogen and methyl thio
and
n
0, 1, 2 or 3, where the radicals R ³ can be different if the value of n is <1,
where the compounds 1. 3,4-di (methylthio) thiophene, 2. 4,4′-di (methylthio) -2,2′-bithiophene, 3. 4,4′-di (methylthio) -2,2 ′ : 5 ′, 2′′terthiophene, 4. 3′-methylthio-2,2 ′: 5 ′, 2 ′ ′ - terthiophene and 5. 4.4 ′ ′ - di (methylthio) -2.2 ′: 5 ′ , 2 ′ ′: 5 ′ ′, 2 ′ ′ ′ - quarterthiophene are of particular importance.

Also special in terms of biological activity preferred compounds of formula I 'are in the following Compiled table:

The compounds of formula I 'are suitable for pests effective in the class of insects, arachnids and nematodes to fight. You can in crop protection and on the Hy giene, stock protection and veterinary sector as pest weapons are used.

The harmful insects include from the order of the Butterflies (Lepidoptera) for example Agrotis ypsilon, Agrotis segetum, Alabama argillacea, Anticarsia gemmatalis, Argyresthia conjugella, Autographa gamma, Bupalus piniarius, Cacoecia murinana, Capua reticulana, Cheimatobia brumata, Choristoneura fumiferana, Choristoneura occidentalis, Cirphis unipuncta, Cydia pomonella, Dendrolimus pini, Diaphania nitidalis, Diatraea grndiosella, Earias insulana, Elasmopalpus lignosellus, Eupoecilia amibiguella, Evetria bouliana, Feltia subterranea, Galleria mellonella, Grapholita funebrana, Grapholita molesta, Heliothis armigera, Heliothis virescens, Heliothis zea, Hellula undalis, Hibernia defoliaria, Hyphantria cunea, Hyponomeuta malinellus, Keifferia lycopersicella, Lambdina fiscellaria, Laphygma exigua, Leucoptera coffeella, Leucoptera scitella, Lithocolletis blancardella, Lobesia botrana, Loxostege sticticalis, Lymantria dispar, Lymantria monacha, Lyonetia clerkella, Malacosoma neustria, Mamestra brassicae, Orgyia pseudotsugata, Ostrinia nubilalis, Panolis flamea,  Pectinophora gossypiella, Peridroma saucia, Phalera bucephala, Phthorimaea operculella, Phyllocnistis citrella, Pieris brassicae, Plathypena scarbra, Plutella xylostella, Pseudoplusia includens, Phyacionia frustrana, Scrobipalpula absoluta, Sitotroga cerelella, Sparganothis pilleriana, Spodoptera frugiperda, Spodoptera littoralis, Spodoptera litura, Thaumatopoea pityocampa, Tortrix viridana, Trichoplusia ni, Zeiraphera canadensis.

From the order of the beetles (Coleoptera), for example Agrilus sinuatus, Agriotes lineatus, Agriotes obscurus, Amphimallus solstitialis, Anisandrus dispar, Anthonomus grandis, Anthonomus pomorum, Atomaria linearis, blastophagus piniperda, Blitophaga undata, Bruchus rufimanus, Bruchus pisorum, Bruchus lentis, Byctiscus betulae, Cassida nebulosa, Cerotoma trifurcata, Ceuthorrhynchus assimilis, Ceuthorrynchus napi, Chaetocnema tibialis, Conoderus vespertinus, Crioceris asparagi, Diabrotica longicornis, Diabrotica 12-punctata, Diabrotica virgifera, Epilachna varivestis, Epitrix hirtipennis, Eutinobothrus brasiliensis, Hylobius abietis, Hypera brunneipennis, Hypera postica, Ips typographus, Lema bilineata, Lema melanopus, Leptinotarsa decemlineata, Limonius californicus, Lissorhoptrus oryzophilus, Melanotus communis, Meligethes aeneus, Melolontha hippocastani, Melolontha melolontha, Onlema oryzae, Ortiorrhynchus sulcatus, Otiorrhynchus ovatus, Phaedon cochleariae, Phyllotreta chrysocephala, Phyllophaga sp., Phyllopertha horticola, Phyllotreta nemorum, Phyllotreta striolata, Popillia japonica, Sitona lineatus, Sitophilus granaria.

From the order of the two-winged birds (Diptera), for example Aedes aegypti, Aedes vexans, Anastrepha ludens, Anopheles maculipennis, ceratitis capitata, Chrysomya bezziana, Chrysomya hominivorax, Chrysomya macellaria, Contarinia sorghicola, Cordylobia anthropophaga, Culex pipiens, Dacus cucurbitae, Dacus oleae, Dasineura brassicae, Fannia canicularis, Gasterophilus intestinalis, Glossia morsitans, Haematobia irritans, Haplodiplosis equestris, Hylemyia platura, Hypoderma lineata, Liriomyza sativae, Liriomyza trifolii, Lucilia caprina, Lucilia cuprina, Lucilia sericata, Lycoria pectoralis, Mayetiola destructor, Musca domestica, Muscina stabulans, Oestrus ovis, Oscinella frit,  Pegomya hysocyami, Phorbia antiqua, Phorbia brassicae, Phorbia coarctata, Rhagoletis cerasi, Rhagoletis pomonella, Tabanus bovinus, Tipula oleracea, Tipula paludosa.

From the order of the thrips (Thysanoptera) for example Frankliniella fusca, Frankliniella occidentalis, Frankliniella tritici, Scirtothrips citri, Thrips oryzae, Thrips palmi, Thrips tabaci.

From the order of the hymenoptera, for example Athalia rosae, Atta cephalotes, Atta sexdens, Atta texana, Hoplocampa minuta, Hoplocampa testudinea, Monomorium pharaonis, Solenopsis geminata, Solenopsis invicta.

From the order of the bugs (Heteroptera), for example Acrosternum hilare, Blissus leucopterus, Cyrtopeltis notatus, dysdercus cingulatus, dysdercus intermedius, Eurygaster integriceps, Euchistus impictiventris, Leptoglossus phyllopus, Lygus lineolaris, Lygus pratensis, Nezara viridula, Piesma quadrata, Solubea insularis, Thyanta perditor.

From the order of the plant suckers (Homoptera) for example wise Acyrthosiphon onobrychis, Adelges laricis, Aphidula nasturtii, Aphis fabae, Aphis pomi, Aphis sambuci, Brachycaudus cardui, Brevicoryne brassicae, Cerosipha gossypii, Dreyfusia nordmannianae, Dreyfusia piceae, Dyasphis radicola, Dysaulacorthum pseudosolani, Empoasca fabae, Macrosiphum avenae, Macrosiphum euphorbiae, Macrosiphon rosae, Megoura viciae, Metopolophium dirhodum, Myzodes persicae, Myzus cerasi, Nilaparvata lugens, Pemphigus bursarius, Perkinsiella saccharicida, Phorodon humuli, Psylla mali, Psylla piri, Rhopalomyzus ascalonicus, Rhopalosiphum maidis, Sappaphis mala, Sappaphis mali, Schizaphis graminum, Schizoneura lanuginosa, Trialeurodes vaporariorum, viteus vitifolii.

From the order of the termites (Isoptera), for example Calotermes flavicollis, Leucotermes flavipes, Reticulitermes lucifugus, Termes natalensis.  

From the order of the straight wing aircraft (Orthoptera), for example Acheta domestica, Blatta orientalis, Blattella germanica, Forficula auricularia, Gryllotalpa gryllotalpa, Locusta migratoria, Melanoplus birittatus, Melanoplus femur-rubrum, Melanoplus mexicanus, Melanoplus sanguinipes, Melanoplus spretus, Nomadacris septemfasciata, Periplaneta americana, Schistocerca americana, Schistocerca peregrina, Stauronotus maroccanus, Tachycines asynamorus.

Arachnoid, for example, arachnids (Acarina) like Amblyomma americanum, Amglyomma variegatum, Argas persicus, Boophilus annulatus, Boophilus decoloratus, Boophilus microplus, Brevipalpus phoenicis, Bryobia praetiosa, Dermacentor silvarum, Eotetranychus carpini, Eriophyes sheldoni, Hyalomma truncatum, Ixodes ricinus, Ixodes rubicundus, Ornithodorus moubata, Otobins megnini, Paratetranychus pilosus, Permanyssus gallinae, Phyllocaptrata oleivora, Polyphagotarsonemus latus, Psoroptes ovis, Rhipicephalus appendiculatus, Rhipicephalus evertsi, saccoptes scabiei, tetranychus cinnabarinus, Tetranychus kanzawai, Tetranychus pacificus, Tetranychus telarius, Tetranychus urticae.

From the class of nematodes, for example, root gall nematodes, e.g. B. Meloidogyne hapla, Meloidogyne incognita, Meloidogyne javanica, cyst-forming nematodes, e.g. B. Globodera rostochiensis, Heterodera avenae, Heterodera glycinae, heterodera schatii, hetrodera triflolii, stick and leaf flakes, e.g. B. Belonolaimus longicaudatus, Ditylenchus destructor, Ditylenchus dipsaci, Heliocotylenchus multicinctus, Longidorus elongatus, Radopholus similis, Rotylenchus robustus, Trichodorus primitivus, Tylenchorhynchus claytoni, Tylenchorhynchus dubius, Pratylenchus neglectus, Pratylenchus penetrans, Pratylenchus curvitatus, Pratylenchus goodeyi.

The active ingredients as such, in the form of their form stungen or the use forms prepared from it, for. B. in Form of directly sprayable solutions, powders, suspensions sions or dispersions, emulsions, oil dispersions, Pa most, dusts, sprinkles, granules by spraying spraying, dusting, scattering or pouring be det. The application forms depend entirely on the  Uses; in any case, they should, if possible finest distribution of the active ingredients according to the invention Afford.

For the production of directly sprayable solutions, Emul sions, pastes or oil dispersions come mineral oil fractions from medium to high boiling point, such as kerosene or diesel oil, as well as coal tar oils and vegetable oils or of animal origin, aliphatic, cyclic and aromatic hydrocarbons, e.g. B. benzene, toluene, xylene, Paraffin, tetrahydronaphthalene, alkylated naphthalenes or their derivatives, methanol, ethanol, propanol, butanol, Chloroform, carbon tetrachloride, cyclohexanol, cyclohexa non, chlorobenzene, isophorone, strongly polar solvents, e.g. B. dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, Water.

Aqueous use forms can be made from emulsion concentrates, Pastes or wettable powders (wettable powders, oil dispersions) can be prepared by adding water. For production of The substances can be emulsions, pastes or oil dispersions as such or dissolved in an oil or solvent, with wetting, adhesive, dispersing or emulsifying agents in Was be homogenized. But it can also be more effective Substance wetting, adhesive, dispersing or emulsifying agent and any concentrates that are solvent or oil be made suitable for dilution with water are.

Alkali, alkaline earth, Ammonium salts of lignosulfonic acid, naphthalenesulfonic acid, Phenolsulfonic acid, dibutylnaphthalenesulfonic acid, alkylaryl sulfonates, alkyl sulfates, alkyl sulfonates, fatty alcohol sulfates and fatty acids and their alkali and alkaline earth metal salts, salts of sulfated fatty alcohol glycol ether, condensation products of sulfonated naphthalene and naphthalene derivatives with formaldehyde, condensation products of naphthalene or the naphthalene sulfonic acid with phenol and formaldehyde, poly oxyethylene octylphenol ether, ethoxylated isooctylphenol, Octylphenol, nonylphenol, alkylphenol polyglycol ether, tri butylphenyl polyglycol ether, alkylaryl polyether alcohols, iso tridecyl alcohol, fatty alcohol ethylene oxide condensates, ethoxy gated castor oil, polyoxyethylene alkyl ether, ethoxylated  Polyoxypropylene, lauryl alcohol polyglycol ether acetal, sorbitol esters, lignin sulfite liquors and methyl cellulose in Be dress.

Powders, materials for spreading and dusts can be mixed or grinding the active substances together with a solid carrier.

Examples of formulations are:

I. 5 parts by weight of compound no Parts by weight of finely divided kaolin mixed intimately. Man he in this way holds a dust that contains 3% by weight of the Contains active ingredient.

II. 30 parts by weight of compound no. 2 are mixed with a Mi made from 92 parts by weight of powdered silica gel and 8 parts by weight of paraffin oil, which is applied to the surface this silica gel was sprayed, mixed intimately. In this way a preparation of the effect is obtained fabric with good adhesion.

III. 10 parts by weight of compound no. 4 are in a Mi solved, consisting of 90 parts by weight of xylene, 6 parts by weight len of the adduct of 8 to 10 moles of ethylene oxide on 1 mole of oleic acid-N-monoethanolamide, 2 parts by weight Calcium salt of dodecylbenzenesulfonic acid and 2 parts by weight len of the adduct of 40 moles of ethylene oxide with 1 Mole of castor oil.

IV. 20 parts by weight of compound no. 5 are in a Mi dissolved in 60 parts by weight of cyclohexanone, 30 Parts by weight of isobutanol, 5 parts by weight of the addition product of 7 moles of ethylene oxide with 1 mole of isooctyl phenol and 5 parts by weight of the adduct of 40 Moles of ethylene oxide to 1 mole of castor oil.

V. 80 parts by weight of compound no Parts by weight of the sodium salt of diisobutylnaphthalene alpha-sulfonic acid, 10 parts by weight of the sodium salt ner lignin sulfonic acid from a sulfite waste liquor and 7  Parts by weight of powdered silica gel mixed well and ground in a hammer mill.

Granules, e.g. B. wrapping, impregnation and homogeneous granules, can bind the active ingredients to solid Carriers are produced. Solid carriers are e.g. B. mineral earths, such as silica gel, silicas, silica gels, Silicates, talc, kaolin, attaclay, limestone, lime, chalk, Bolus, loess, clay, dolomite, diatomaceous earth, calcium and Magnesium sulfate, magnesium oxide, ground plastics, Fertilizers such as B. ammonium sulfate, ammonium phosphate, Ammonium nitrate, ureas and herbal products such as Ge cereal flour, tree bark, wood and nutshell flour, cellulo sepulver and other solid carriers.

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

The drug concentrations in the ready-to-use Zu Preparations can be varied in larger areas.

In general, they are between 0.0001 and 10%, preferably between 0.01 and 1%.

The active ingredients can also be used successfully in the Ultra-low-volume (ULV) processes are used is possible formulations with more than 95 wt .-% active ingredient or even apply the active ingredient without additives.

The amount of active ingredient applied outdoors conditions 0.2 to 10, preferably 0.5 to 2.0 kg / ha.

Various types of oils, herbicides, Fungicides, other pesticides, bactericides, if necessary, only immediately before use (Tank mix) can be added. These funds can be added to the he agents according to the invention in a weight ratio of 1:10 to 10: 1 be added.  

Synthesis examples

Those reproduced in the synthesis examples below Regulations have been modified accordingly gangsverbindungen for obtaining further compounds I 'be uses. The compounds thus obtained are in the closing table with physical data.

The following starting compounds that cannot be purchased were according to produced according to the given literature regulations:

• 1) 3-methylthiothiophene, bp. 103-105 ° C / 30 Torr, Yield 80% (GC <99%);
• 2) 2-bromo-3-methylthiothiophene, bp 54-56 ° C / 10 ^-3 torr, yield 93.4% (GC <98%);
• 3) 2,5-dibromo-3-methylthiothiophene, yield 83% (GC <98%);
• 4) 2-bromo-4-methylthiothiophene, b.p. 114-116 ° C / 12 torr, Yield 84% (GC <98%);

Literature: E.C. Taylor, D.E. Vogel, J. Org. Chem. 50 1002 (1985)

• 5) 3,4-dibromothiothiophene, bp 94-95 ° C / 12 torr, Yield 60% (GC <97%);

Literature: S. Gronowitz, Acta Chem. Scand. 13 (5) 1045 (1959)

• 6) 5,5'-dibromo-2,2'-bithiophene, mp. 146-147 ° C (GC <99%)

Literature: F. Würthner, diploma thesis university Stuttgart 1990

Example 1: Preparation of 3,4-di (methythio) thiophene

1.1 Under a protective gas atmosphere, a mixture of 107.5 ml (0.172 mol) butyllithium (1.6 molar solution in Hexane) and 40 ml of diethyl ether at -80 ° C dropwise with a solution of 19.36 g (0.08 mol) of 3,4-dibromothio phen in 30 ml of diethyl ether. After 1 hour with this one The reaction mixture became temperature with a solution of 16.2 g (0.172 mol) of dimethyl disulfide in 20 ml  Diethyl ether added and after the addition is complete Stirred at -70 ° C for 3 h. After the networking has ended the reaction mixture is heated to about 25 ° C. For The mixture was worked up with 1N hydrochloric acid hydro lysed and washed with water. By double De Stillation of the organic phase gave 8.31 g (50% of theory) 3-bromo-4- (methylthio) thiophene as colorless Liquid (bp: 112-115 ° C / 10 Torr; GC purity <98%).

1.2 A mixture of 0.486 g (20 mmol) of magnesium shavings (I ₂ -etched) and 30 ml of diethyl ether was added dropwise at 25 ° C. with 4.18 g (20 mmol) of 2-bromo-4- (methylthio ) - added thiophene. After 3 hours at the reflux temperature, the reaction mixture was cooled to about 0 ° C. and added dropwise at this temperature to a mixture of 3.55 g (17 mmol) of 2-bromo-4- (methylthio) thiophene, 7 ml of diethyl ether and 0.078 g (0.14 mmol) Ni (dppp) Cl ₂ dpp = 1,3-bis (diphenylphosphino) propane. After the addition had ended, the reaction mixture was stirred again at reflux temperature for 17 h. For working up, the cooled mixture was hydrolyzed with 1N hydrochloric acid and washed with water. Removal of the solvent, chromatography (silica gel / benzene) and recrystallization (1st benzene / hexane 1/1; 2nd dioxane) gave 2.92 g (66% of theory) 3,4-di (methythio) thiophene as colorless crystals (active substance example 2; GC purity: <99%).

General instructions for the synthesis of methylthio-substi did oligothiophenes using the example of 4,4'-di (methylt hio) -2,2′-bithiophene (2).

4.18 g (20 mM) of 2-bromo-4-methylthithiophene are added dropwise under nitrogen to 0.486 g (20 mM) of magnesium shavings (I ₂ -etched) in 30 ml of absolute ether in a two-necked flask with reflux condenser and dropping funnel. After heating for 3 hours under reflux, the Grignard solution is transferred using cannula technology into the dropping funnel of a second apparatus. There, 3.55 g (17 mM) of 2-bromo-4-methylthithiophenyl in 7 ml of ether and 0.078 g (0.14 mM) of Ni (dppp) Cl ₂ (nickel diphenylphosphinopropane dichloride) are initially introduced as a catalyst in a three-necked flask. At 0 ° C, the Grignard solution is slowly added dropwise to the mixture of the dibromothiophene and the catalyst, the catalyst dissolving immediately with a brown color. When the addition is complete, the mixture is then heated to boiling for 17 h. Since is hydrolyzed with 1 N HCl and the combined organic phases washed neutral. After the solvent has been stripped off, the product is chromatographed on silica gel using benzene as the mobile phase. Two recrystallizations of the greenish colored eluate first from benzene / hexane with the addition of activated carbon and then from dioxane gives 2.92 g (66% of theory) of colorless crystals (GC <99%).

Amounts used for the other oligomers:
4,4′-di (methylthio) -2.2 ′; 5 ′, 2 ′ ′ - terthiophene (3):
5.02 g (24 mM) 2-bromo-4-methylthithiophene in 40 ml ether
0.583 g (24 mM) magnesium (I ₂ -etched)
0.011 g (0.02 mM) Ni (dppp) Cl ₂
3.638 g (12.6 mM) 2,5-dibromothiophene in 15 ml ether. Chromatography hexane / CH ₂ Cl ₂ 85:15. 1.44 g (35% of theory; GC <99%) of yellow crystals are isolated from the second fraction.

4,4; ′ - Di (methylthio) -2,2 ′; 5′2 ′ ′; 5 ′ ′, 2 ′ ′ ′ - quaterthiophen (4):
5.02 g (24 mM) 2-bromo-4-methylthithiophene in 40 ml ether, 0.583 g (24 mM) magnesium (I ₂ -etched)
0.026 g (0.04 mM) Ni (dppp) Cl ₂
3.24 g (10 mM) 5,5'-dibromo-2,2'-bithiophene in 100 ml
Ether / 50 ml of benzene dissolved
Reflux 22 h, extraction with CH ₂ Cl ₂ ,
Chromatography hexane / CH ₂ Cl ₂ 1: 1,
Recrystallization from toluene, yield 2.65 g (63% of theory)
orange crystals (HPLC <99%).

3′-methylthio-2,2 ′; 5 ′, 2; -terthiophene (5):
8.17 g (50 mM) 2-bromothiophene in 50 ml ether
1.22 g (24 mM) magnesium (I ₂ -etched)
0.27 g (0.5 mM) Ni (dppp) Cl ₂
5.77 g (20 mM) 2,5-dibromo-3-methylthiothiophene in 30 ml ether
Reflux 40 h, extraction with ether / CH ₂ Cl ₂ ,
Chromatography hexane / CH ₂ Cl ₂ 80:20 and 90:10,
Yield 3.82 g (65% of theory; GC <99%).

Examples of use

The biological effect of the compounds of the general Formula I was shown by the following tests:

The active ingredients were

• a) as a 0.1% solution in acetone or
• b) as a 10% emulsion in a mixture of 70 wt .-% Cy clohexanone, 20% by weight Nekanil® LN (Lutensol® AP6, network medium with emulsifying and dispersing action on the basis ethoxylated alkylphenols) and 10% by weight Emulphor® EL (Emulan® EL, emulsifier based on ethoxylated Fatty alcohols)

processed and according to the desired concentration with acetone in the case of a) or with water in the case of b) diluted.  

After the end of the tests, the lowest was in each case Concentration determined at which the compounds in Ver 80-100 for untreated control tests % inhibition or cause mortality (threshold effect or minimum concentration).

Claims (14)

1. Thiophenes and polythiophenes of the formula I in which the substituents and the index have the following meaning:
R ¹ , R ² and R ³ independently of one another are hydrogen and C ₁ -C ₁₈ -alkylthio,
n
0, 1, 2, 3, 4 or 5, where the radicals R ³ can be different if the value of n is <1,
where R ¹ , R ² and R ³ do not simultaneously mean hydrogen and where R ^{1 is} not hydrogen if R ^{2 is} methylthio and n is 0. 2. thiophenes and polythiophenes of the formula I according to claim 1, in which the substituents and the index have the following meaning:
R ¹ , R ² and R ³ independently of one another are hydrogen and C ₁ -C ₈ -alkylthio,
n
0, 1, 2, 3 or 4, where the radicals R ³ can be different if the value of n is <1,
where R ¹ , R ² and R ³ do not simultaneously mean hydrogen and where R ^{1 is} not hydrogen when R ^{2 is} methylthio and n is 0. 3. thiophenes and polythiophenes of the formula I according to claim 1, in which the substituents and the index have the following meaning:
R ¹ , R ² and R ³ independently of one another are hydrogen and C ₁ -C ₃ -alkylthio,
n
0, 1, 2, 3 or 4, where the radicals R ³ can be different if the value of n is <1,
where R ¹ , R ² and R ³ do not simultaneously mean hydrogen and where R ^{1 is} not hydrogen when R ^{2 is} methylthio and n is 0. 4. thiophenes and polythiophenes of Fornel I according to claim 1, in which the substituents and the index have the following meaning:
R ¹ , R ² and R ^{3 are} independently hydrogen and methylthio and
n
0, 1, 2 or 3, where the radicals R ^{3 can be} different if the value of n is <1,
where R ¹ , R ² and R ³ do not simultaneously mean hydrogen and where R ^{1 is} not hydrogen if R ^{2 is} methylthio and n is 0. 5. 3,4-di (methylthio) thiophene. 6. 4,4'-di (methylthio) -2,2'-bithiophene. 7. 4,4'-Di (methylthio) -2,2 ': 5', 2 '' - terthiophene. 8. 3'-methylthio-2,2 ': 5', 2 '' - terthiophene. 9. 4.4 ′ ′ - Di (methylthio) -2.2 ′: 5 ′, 2 ′ ′: 5 ′ ′, 2 ′ ′ ′ - quarterthiophene.   10. A process for the preparation of the compounds of formula I according to claim 1, in which n has the value 0, characterized in that

• a) a halogen thiophene of the formula IIa in which Hal represents a halogen atom, in a manner known per se in a solvent in the presence of an alkali metal organyl with a disulfide of the formula IIIaR¹-R¹ (IIIa) or
• b) a halogen thiophene of the formula IIb in which Hal represents a halogen atom, in a manner known per se in a solvent in the presence of an alkali metal organyl with a disulfide of the formula IIIa, first in a compound IV transferred, which is then reacted under the same conditions with a disulfide of the formula IIIbR²-R² (IIIb) to I.

11. A process for the preparation of the compounds of formula I according to claim 1, characterized in that a halothiophene of formula IIc in which Hal represents a halogen atom, in a manner known per se in a solvent in the presence of magnesium in the corresponding Grignard compound of the formula V. transferred, which is then in a manner known per se in a solvent with a halogen thiophene or polythiophene of the formula IId to I is implemented. 12. Pesticides, comprising an effective amount of at least one compound of the formula I ' in which the substituents and the index have the following meaning:
R ¹ , R ² and R ³ independently of one another are hydrogen and C ₁ -C ₁₈ -alkylthio,
n
0, 1, 2, 3, 4 or 5, where the radicals R ³ can be different if the value of n is <1,
and inert additives. 13. Method of combating pests, thereby characterized in that the pests and / or their Habitat with an effective amount of at least one Compound of formula I 'treated according to claim 12. 14. Use of the compounds of formula I 'according to Claim 12 for controlling pests.