LU81778A1 - 2-BROMOBENZYL ESTERS AND THEIR USE AS PESTICIDES - Google Patents

Description

OC 5ο.743

f & AND-DUCHY OF LUXEMBOURG

......... VJ .......... '* du ll .... octobEe..l97.9 ... Minister, ôyf * |! B of Economy National and Middle Classes

Book title: ---------------------------------------- XSâ- yS. , ......

Industrial Property Service

IT · {q LUXEMBOURG

n'm, D emande de Brevet d'Invention I. Request .... La .... s.oc ± £ fcé _dita.s .SHELL ......... (i) .... .Caral .... \ rân..Bylândtla £ n .. 3o, ..... à..LA..MhXK, ..... PaYS-Bas.x .... reprS · -... ...........

..... santSe ... by ... Monsieur ..... ^ agj ^ sMfe-j ^ jguaMtS .............. (2> -.de ... .mandafcaire ................................................ .................................................. .................................................. .............................................: .... ........................

deposits this 01136 October ISOO SO.! X & Rte-dix-neuf ..................................... ........ (3) at ........ 1.5 ............ .... hours, at the Ministry of National Economy and the Middle Classes , in Luxembourg: k 1. the present request for obtaining a patent for an invention concerning: ..... lil3atar.s .... da „2 = b.rDÂLihi3iïKylfi ... ®.t._igittr ^ MMsay ^ LÆQî3Siê _ ^^ J ^ .............. m ......... aidas .. "., ............ .................................................. .................................................. .................................................. .................................................. ..................................

declares, assuming responsibility for this declaration, that the inventor (s) is (are): .... Iiichae.1 ..... Ja! m .... 3.llldj. ^. ... l9 .... 3urnfcwiak ..... Drive./......x^QWG.r.jlalafcçw,.....Kant,...________{5) ..... to & ndarBr & fc & gne ................................................. .................................................. .................................................. .................................................. ..............

2. the delegation of power, dated ........ ïs & „. ÔÂVS ............................. .... on _____13 & OÛ ~ fc 1979 .............

3. description in language .............. frÂU.ÇA.iS-S ...................... ........ of the invention in two copies; 4 .............. drawing boards, in two copies; 5. the receipt of the taxes paid to the Luxembourg Registration Office, on 11 .. oafcohre .... 19.7.9 ...................... .................................................. .................................................. .................................................. .................................

claims for the above patent application the priority of one (or more) application (s) of (6) .......................... bravet ......................................... filed © in (7) ... .................................................. ..............

* le ....... 13 ..... QatGbre ..... I9.7.S .......... (Nq. * ..... 4o42o / 7S1 .. .................................................. .................................................. ............... ® * * ................................ .................................................. .................................................. .................................................. ............ „„ ”.” „” »„ H ·.,. ·. ·· .................... .....................

in the name of ..... I.â ....! sp.3. & £ .n; fc5r ........................ .................................................. .................................................. .................................................. ........... (9) elects domicile for him / her and, if designated, for his / her agent, in Luxembourg .................. ......................

..... 35, ..... bld * ..... HQval .............................. .................................................. .................................................. .................................................. .......................... (io) requests the grant of a patent for the subject described and represented in the appendices, above, - with adjournment of this issue to ............... ^ ......................... ...month.

\ The V ............ V. l \ î \ __ /) Π. Deposit Minutes

The above application for a patent for invention has been filed with the Ministry of National Economy and the Middle Classes, Industrial Property Service in Luxembourg, dated: October 11, 1579

Pr. The Minister at 3 p.m. S - XC'c National Economy and_Middle Classes,. ...... '' // V. '"• X (p · /

(ofc f% X

Year 1 * 1 ---: -.— fi-Z_J --- D. 50.743

CLAIM OF PRIORITY

of the patent application /

In GREAT BRITAIN OF OCTOBER 13, 1978

’: ÛXlVmT

Brief Description filed in support of a request for

PATENT

1 au j Luxembourg ’ιί i \ 4 in the name of: SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ B.V.

"i jü \\ II, for:" 2-Bromobenzyl esters and their use as j; pesticides ".

ii y \ i i | !: i: i i; i · i li

J

2 • Ί? (1) Η and Ε are independently selected from fluorine, chlorine and bromine, (2) X is hydrogen or a cyano group, ($) X is hydrogen, 5 (4-) n is i, (5) Y is chosen by hydrogen, fluorine, chlorine and bromine, (6) Y is a substituent 6-fluoro, 6-chloro or 6-broiio, preferably 6-fluoro or 6-chloro , 10 (7) portion 2 (2-R'-2-R '~ vinyl) ~ 3.3 “àiméthylcuclo ~ propane carboxyl in the cis configuration, (8) portion 2 (2-B ^ -2-R2 -vinyl) -3,3-dinethylcyclo-propane carboxyl has the configuration * lR ~ cis.

The 2-bromobenzyl esters of formula I can be - * [<2 can be prepared by methods analogous to those used for known compounds. A convenient method comprises the reaction of a comnose of formula II

V

H CH = 0 ^ 20 \ / A (II) CH5 _ / _ \ -_coz

Cïï5 H

25 with a compound of formula III:

Br X \ _ Q - CH_ (III) ·? ° (ï) n

/ J P

whereE, E, X, Y and n are as defined above, one of the substituents Q and Z represents a halogen atom, 3 preferably a chlorine or chromium atom, and the other represents a hydroxy group. The reaction is preferably carried out in the presence of an appropriate base, for example of a tertiary amine such as triethylamine or of an alkali metal carbonate such as potassium or sodium carbonate, in the presence of an inert solvent. Conveniently, Z represents a hydroxy group and Q represents a chlorine or bromine atom.

The compounds of formula II above and their individual isomers are conveniently prepared in a known manner, for example as described in British patents Hos 1,413,491 and 1,448,228.

The compounds of formula III above in which X is hydrogen and Q is halogen are conveniently prepared by halogenation of corresponding halobromotoluens. The halobromotoluenes can be obtained by introduction of the appropriate halogen by diazotization of the appropriate halotoluidine. The halogenotoluidines can be prepared by reduction of the corresponding haloDitrotoluene by known methods, for example that of Entwistle et al., J.C.S.

, Perkin I, 1977 ”pages 443 and 444. Compounds of formula III in which X is hydrogen and Q is hydroxy- can be prepared by hydrolysis of the 23 compounds in which Q is halogen.

Compounds of formula III in which X is a cyano, ethynyl or thioamido group can be prepared in a known manner from those in which X is hydrogen via the aldehyde 3Q corr e sp ond an t.

The 2-hromohenzyl esters according to the invention are useful as pesticides, especially as insecticides and acaricides for domestic applications and in agriculture. The invention therefore comprises 4, in its general context, pesticidal compositions comprising a vehicle and / or a surface-active agent at the same time as, as active ingredient, a 2-bromo-benzyl ester of formula I. The invention also comprises a method for controlling in a place against harmful insects, ticks and / or mites, characterized in that a pesticide-effective amount of an ester ôè 2,6- is applied in this place dihalogenobensyl according to the invention or of a composition containing such a compound, * The term "vehicle", as used herein, denotes a material, which can be inorganic or organic and of synthetic or natural origin, with which the active compound is mixed or made up in composition for fa-! 15 cilitate its application to the plant, seeds, soil or another object to be treated or its storage, its S. transport or handling. The vehicle can be a solid or a liquid. Any of the materials commonly used in the preparation of pesticide, herbicide or fungicide compositions can be used as the vehicle. Solid vehicles which can be used are argi and natural and synthetic silicates, for example natural silicas. like diatomaceous earth; magnesium silicates, for example talcs; magnesium and aluminum silicates, for example attack pulpites and verniculites; aluminum silicates, for example kaolinites, montmorillonites and micas; calcium carbonates; calcium sulfate; 50 synthetic hydrated silicon oxides and synthetic calcium or aluminum silicates; elements, for example carbon and sulfur; natural and synthetic resins such as, for example, Λ / Û 5 coumarone resins, polyvinyl chloride and styrene polymers and copolymers; solid polychlorophenols; "bitumen; waxes, such as for example beeswax, paraffin wax and chlorinated mineral waxes; and solid fertilizers, for example superphosphates.

Liquid carriers which can be used are water, • alcohols, for example isopropanol and glycols; ketones, for example acetone, methyl ethyl ketone and cyclohexanone; ethers; aromatic hydrocarbons, for example benzene, toluene and xylene; petroleum fractions, for example kerosene and light mineral oils; chlorinated hydrocarbons, for example carbon tetrachloride, perchlorethylene, trichloroethane; and gaseous compounds, normally in the vapor state, liquefied.

Mixtures of different liquids are often used.

The surfactant can be an emulsifying agent or a dispersing agent or a wetting agent; it can be non-ionic or ionic. Any of the surfactants commonly used in the preparation of pesticidal, herbicidal or fungicidal compositions can be used. Examples of usable surfactants are the sodium or calcium salts of polyacrylic acids and lignin-sulfonic acids; condensation products of fatty acids or aliphatic amines or amides containing at least 12 carbon atoms in the molecule with ethylene oxide and / or propylene oxide; fatty acid esters of glycerol, sorbitan, sucrose or pentaerythritol; condensation products of these esters.

/ 6 ί with ethylene oxide and / or propylene oxide; condensation products of fatty alcohols or of alkyl phenols, for example p-octylphenol or p-octylcresol, with ethylene oxide and / or propylene oxide; sulfates or sulfonates of these condensation products; '' alkali or alkaline earth metal salts, preferably sodium salts, sulfuric acid esters or sulfonic acids containing at least 10 carbon atoms in the molecule, for example lauryl sul- * Sodium fate, sodium sec-alkyl sulfates, sodium salts of sulfonated castor oil and sodium alkyl-aryl sulfonates such as dodecylbenzene sulfa-; te of sodium; and polymers of ethylene oxide and copolymers of ethylene oxide and propylene oxide.

; The compositions according to the invention may be presented in the form of wettable powders, dusting powders, granules, solutions, concentrates; highly emulsifiable, emulsions, suspended concentrates and aerosols. Wettable powders are usually made up of strips containing 25 ”50 or 75% toxic and usually contain | more than one solid vehicle, from 31 to 0% by weight of a dispersing agent and, when necessary, from 0 to 10% by weight of one or more stabilizers and / or other additives such as penetrating agents or glues.

| The dusting powders are usually presented ί in the form of a powder concentrate having a composition similar to that of a wettable powder but without! 30 dispersant, and they are diluted at their place of use; tion with an additional quantity of solid vehicle; "to give a composition usually containing from 0.5 to 10% by weight of toxiaueo The granules are usual-

He / * i ^ m! They are also prepared so as to have a size of between 0.152 and 1.676 mm and they can be produced by agglomeration or impregnation techniques. Generally, granules will contain from 0.5 to 25% in 5 weight of toxic and 0 to 10% by weight of additives such as stabilizers, slow release modifiers and binders, emulsifiable concentrates usually contain, in addition to the solvent and, when necessary , cosolvent, from 10 to 50% by weight of toxic, from 2 to 20% by weight / volume of emulsifiers and from 0 to 20% by weight / volume of suitable additives such as stabilizers, penetrating agents and corrosion inhibitors ", The suspended concentrates are composed so as to obtain a stable, non-settling fluid product and they usually contain from 10 to 75% by weight of toxic, from 0.5 to 15% by weight of dispersing agents, from 0.1 to 10% by weight of suspending agents such as col protective loids and thixotropic agents, from 0 to 10% by weight of suitable additives such as demulsifiers, corrosion inhibitors, stabilizers, penetrating agents and adhesives and, as a vehicle, water or a organic liquid in which the toxic is substantially insoluble; certain organic solids or inorganic salts may be dissolved in the vehicle to help prevent sedimentation or as antifreezes for water ", aqueous dispersions and emulsions, for example composites obtained by diluting a wettable powder or concentrate according to the invention with water, are also included in the general framework of the present invention · * These emulsions can be of the water-in-oil type or of the oil-in-water type and they 7 * 8 \ can have a thick consistency of "mayonnaise1 · 1

The compositions according to the invention can also contain other ingredients, for example other compounds having pesticidal, herbicidal or fungicidal properties.

The invention will be better understood from the following examples.

- EXAMPLE 1 - Preparation of 2- (2,2-dichlorovinyl) ~ 3 "3" dimethyl-cyclopropane carboxylate 1: 1 10 cis / trans 2-bromo ~ 6-chlorobensyle_ a) Braride prenaration of 2-bromo-e -chloroben2yle i I We stir together 2-bromo-6-chlorotoluene (20.55 g) and lî-bromosuccinimide (19 * 6 g) in carbon tetrachloride (100 cm ^) while heating at reflux during 15 22 hours with exposure to radiation from an infrared lamp, The resulting solution is cooled in j ice, filtered and evaporated to give the title compound I which is dissolved in petroleum ether j. (60-80), part is recrystallized from the sculpion in the form of pink needles (8.5 g) and part is collected by evaporation in the form of a dark orange solid (17 , 7 g) (total production 26.2 g, yield 92%).

b) Preparation of 2- (2,2-dichlorovinyl) -5,3-dimethyl-2 ^ cyclopropane carboxylate of 1: 1 cis / trans 2-bromo-6-chlorobenzyl __________

Stir 1: 1 cis / trans acid together 2- (2,2-dichlorovinyl) -3.3 ~ (iiE1sthylcyclopropane carboxy-lique (2.3 g), 2-bromo-6-chlorohenzyl bromide 30 (2.85 g) and potassium carbonate (1.6 g) in acetone (50 cm 3) under reflux for 6 hours. The reaction mixture is cooled, diluted with water and treated by extraction three times with 50 cm 3 portions of ethyl oxide, the combined res ether extracts are washed with water and with an aqueous solution of sodium bicarbonate (three times), dried over sulphate magnesium and evaporated to give the orange product of the tire (4.1 g, 98%), melting point 6i-67 ° C.

10 Ad al vs e

Calculated for: C 45.6; H 5.4; Br 19.4;

Cl 25.9

Found: C 45.8; H 5.4; Br 19.1;

Cl 25.4.

15 - EXAMPLES 2 to 11 -

By methods similar to that used in Example 1, the following compounds are also prepared: 2- (2,2-difluorovinyl) -5,5-dimethylcyclopropane carboxy-late of 1, PL-ci s-2-bromo ~ 6 ~ chlorobenzyl (yield 76%), 20 V = 1> 533, Z ~ £ 7jp = -15.45 (C2 CECl ^) 2- (2,2-dichlorovinyl) -5,5 “<Üméthylcyclopropane carboxy-late de 1: 1 cis / trans-2 ~ bromobenzyl (89% yield) ηψ = 1.5606 2 "(2,2-dichlorovinyl) -5,5-dinethylcyclopropane carboxy-25 late cis-2-bromobenzyl (8Q% yield) n ^ = 1.5614 2- (2,2-dichlorovinyl) -5,5 ~ aimethylcyclopropane trans-2-bronobenzy carbo-xylate 1e (yield 82%) n2 ^ = 1,5600 2- (2,2 “dichlorovinyl ) ~ 5,5-dimethylcyclopropane carboxy-_ ^ te 1, E-cis-2-bromo-6-chloroben zyle (yield 90%) = 1.5682 -26.8 (O, CHCl ^) I ΊΟ 2- ( 2, 2-dibr om ovi nyl) -3 5 3-à imé thyl cy c 1 oprop an ec arb oxy-late de ci_s-2-'bromo-6-chloro'benzyle (yield 84%), melting point 101 ~ 3 ° C.

2- (2-chloro-2-fluorovinyl) ~ 3,3-àiméthylcyclopropane „

^ pis-2-broao-6-fluorobenzyl carboxylate (yield | 65%) melting point 54-54 ° C

2- (2,2-dichlorovinyl) -3,3-dimethylcyclopropane carboxy- | * labe de ci s-2-bromo-6-f luor oben zyl e (yield 66%) point

1 ’melting 68-69 ° C

Ί0 2- (2,2-dichlorovinyl) -3 »3-dimethylcyclopropane carboxy-late of Ί, R-cis-2 ~ broso-6 - iluorobeDzyle (yield 8Ί%) d | 1 = 1,551 £ & ψ - -21, 9 (C2 CHClj) j 2- (2,2 "dibroraovinyl) -3î3" â-in2th.ylcyclopropane carboxy-

late cis ~ 2-broDO-e-fluorobenzyl (yield 74%) Ί5 melting point 66-67 ° C

Pesticide trials

The insecticidal and ticking activity of compounds according to the present invention is determined using! * 20 the following tests:

Insects: I.lisca domestica (Lied.)

Spodoptera littoralis (S.l.)

Aphis fabae (A * fe)

Heliothis zea (lï.z.) i 25 Mites: Tetranychus urticae (T.u.) i Ticks: Boonhilus microplus (E.m.) I '- 1 - -a.

},; The test methods used for each test! - species are indicated below (1) ilusca domestica 30 A solution at 0.4% by weight in acetone of the compound to be tested is prepared and taken up in a syringe r .1

"V

11 ** · micrometric · House flies (i.Tusca donestica) adult females two to three days old are anesthetized with carbon dioxide and 1 μΐ of the test solution is applied to the ventral side of the abdomen ^ each fly, 20 flies being tested. The treated flies are kept in glass jars covered with peeling paper maintained by an elastic band. Cotton wool pads dipped in a dilute solution of sugar are placed on the peeling paper as rotten. After 24 hours, the percentage of dead and dying flies is noted, (2) Spodoptera littoralis (S.l,)

Pairs of leaves are taken from large bean plants and placed on filter paper inside plastic petri dishes. An aqueous composition containing 2Cf, o by weight of acetone, 0.05 # by weight of THITOï X-100 (I.Barque de fabrique) as wetting agent and 0.4 # by weight is sprayed onto the lower surface of the leaves. of the compound to be tested. Various concentrations are obtained by diluting the composition. After spraying, the leaves are allowed to dry for a period of 1/2 hour to 1 hour and then each leaf is infested with ten larvae of the Egyptian cotton leaf worm (Spodoptera littoralis). After 24 hours, note the percentage of dead and dying larvae, (3) Aphis fabae (A.f.)

Tests are carried out on adult mites (Aphis 30 'fabae) by methods similar to that used for Spodoptera littoralis in (2) above, (4) Heliothis zea (H, z,)

We incorporate the composas to try in i. 12 \ I, aqueous solutions containing 20% by weight of acetone, 10.04 / 0 by weight of Atlox 1045A (trademark) and 0.2% by weight of the compound to be tested, more dilute solutions for curves dose-mortality being prepared on day 5 by diluting the 0.2% solution with an aqueous solution at 0.05 $ by weight of Atlox 1045A. the plants cut from it large beans 7 / indsor are placed on a turntable! and spray treated with 4 cm? of solution | * of * test. Immediately after spraying, five larvae of the cob caterpillar (Helio- ί this zea) are transferred to each plant which is introduced into water through a hole through a test panel. and the environment is maintained at a temperature of 27 ° C and 40-50% relative humidity. Mortality is determined ^ 5 after 44 to 46 hours.

j (5) Tetranychus urticg.e (T. u.) jj

It We cut discs from leaves of green bean plants and place them on paper- | filter kept moist by a wad of cotton wool immersed in water. Each disc is infested with ten adult spiders, and then a solution is sprayed on the discs.

Ition or suspension of the compound to be tested in an acetone-water mixture (20 to 80) containing 0.05% of TRITON X-100 (trade mark) as wetting agent, after 25 hours, the number of air is determined. dead and dying genes 1.

: (6) Boophilus microolus (B.m.) i j We prepare a solution at 0.1 $> by weight of the com-! posed to be tested in acetone containing 10% by weight of polyethylene glycol. Various concentrations i are obtained by diluting this solution. 1 ca ^ d / of test solution is uniformly applied to a filter paper inside! / Z "" '' I ^ i 15 • * of a Petri dish. Once the filter paper is dry enough, fold it in half and crimp it along part of its outer edge so as to form a packet. Transfer about 80-100 5 tick tick larvae to the packet. a single host (Boophilus microplus) two to three weeks old and then completely encloses the package. The package is then placed in an incubator at 27 ° C and 80% relative humidity.

* After 24 hours, the package is opened and the ΊΟ percentage of dead and dying larvae is determined.

The results are presented in Table I, in which the experimental species are identified by the initials indicated above and the activity of the compound is expressed in the form of its toxicity index. ^ 5 quoted (T.T.) which is calculated as follows: LCPq of ethyl parathion (standard)

Toxicity index (I.T.) = Tn —- · ·, -— N * LC ^ q aU comP ° Try it out

The potency of the compounds according to the invention was determined to "starch" the insects using the common housefly (l.-usca. Domestica) by means of the test in the chamber of Kearns-I'arch.

♦

The Kaarns-Karch chamber consists of a transparent glass cylinder of 61 cm x 50.5 cm into which flies can be introduced by a panel 25 sliding at one end. 0.2 cm ^ of a 20% solution of KeC ^ / öO ^ of Shellsol K containing active material is sprayed in 1.5 seconds into the chamber at 0.7 kg / cm and the introduction of air for a further 2 seconds to facilitate uniform distribution of the sprayed material. About 70 flies are used in each treatment and the number of flies knocked down 1, 2, 5 »4, 5» 7 and 10 minutes after spraying is counted. The compounds are divided into six classes} ♦ 14.

\ ί; according to the concentration of toxic necessary for 90% of stunned flies to be obtained, that is to say

Class O - 90% at 10 minutes = concentration 0.029% i! Class 1 - 90% at 10 minutes = concentration 0.09% 5 Class 2 - 90% at 10 minutes = concentration 0.1%

Class 9 - 90% at 10 minutes = concentration 0.2%

Class 4 - 90% at 10 minutes = concentration 0.4-% * Class 5 - Less than 90% at 10 minutes = concentration at 0.4% 1q The results of these tests are also given in Table I.

TABLE I

. Compound Toxicity index Class eon- of -------- surrounding the Example Kâ. S.l. k.î. H.z. You. B.m. ^ Xe ^ lÎT __________mouches _ 1 40 140 27 46 10 422 2 2 29 194- 33 + 7 1 240 0. 20 3 4.5 9 6 8.9 13 8 4 4 4.6 20 7 14 21 13 4 3 3.4 * 9 3 6.2 4 + 4 6 43 144 12 78 63 394- -1 7 13 73 14 32 + 147 4 23 8 16 34 14 + 27 290 2 9 20 35 9 + 24 238 1 10 13 44 19 + 14 80 3 11 34 48 27 + 49 481 2 30 + pon test carried out „* y

i-N

Claims (13)

15 β t REVEI'U) I CA TI ORS “III - * - · —.— - -. * 1. A 2-bromobenzyl ester of formula I: R1 H CH = C ^ 5 V ^ R2 B \ ^ · cEj / AcO- O - CH ~ ^ Q> (I) ^ 3 H 10 where Ry. is hydrogen, fluorine, chlorine, "bromine P or iodine, R is fluorine, chlorine, bromine or iodine, H is hydrogen or a cyano, ethyl-nyl group or thioamido, n is an integer from 1 to 4 and Y or each Y is independently selected from hydrogen, fluorine, chlorine, bromine and iodine · 2. An ester according to claim 1, characterized in that R and R are independently selected from fluorine, chlorine and bromine. ; 3) An ester according to one of the claims 1 and 20 2, characterized in that X is hydrogen or a cyano group, 4. An ester according to claim 3i characterized in that X is hydrogen. 3. An ester according to one of claims 1 to 23 4, characterized in that n = 1, 6. An ester according to one of claims 1 to 5, characterized in that Y is chosen for hydrogen, „fluorine, chlorine and bromine, 7. An ester according to one of claims 1 to 5 $ V V 16 1 characterized in that X is a substituent 6 — fluoro,: 6-ch.loro or 6 ~ bromo. 8. An ester according to one of claims 1 to ΙΛ 2 • 6, characterized in that R and R are independently chosen from Xe fluorine, chlorine and "bromine, X is hydrogen, n is 1 and X is a 6-fluoro or 6-chloro substituent :. 9. An ester according to one of claims 1 to 1 2 8, characterized in that the portion 2 (2-R -2-E -vinyl) -f 10 3,3-dimethylcyclopropane earboxyle has a configuration] cis. i 1 1 10. An ester according to one of claims 1 to Ί 2 9, characterized in that the portion 2 (2-R ~ 2 ~ R -vinyl) -3d3> “dimethylcyclopropane earboxyle has the configuration iR-cis * 15 11) A process for preparing a 2-bromobenzyl ester of formula I as defined in one of claims 1 to 10, characterized in that it comprises the reaction of a compound of formula II: R1. '20 ïï CÏÏ = C <! X * (XX) | CH $ -f - COZ CH * H i ^ 2. with a compound of formula III: <j y Br | Q - OH —ξ '\ (III) j - 30 (Ï) D '12. * where R, R, X, Y and p are as defined in i. *** / KÎ '17 claim 1, one of the substituents Q and Z represents a halogen atom and the other represents a hy-droxy group. 12. The 2 ~ bromobenzyl esters prepared by a process according to claim 11 '· A pesticidal composition characterized in that it comprises a vehicle and / or a surface-active agent at the same time as * as the active ingredient, an ester of 2-bromohenzyl according to one of claims 10 1 to 10 and 12. 14. A method of combating harmful organisms in one place, characterized in that • in this place an ester of 2 ~ bromobènzyle is applied according to one of claims 1 to 10 and 12 or a composition according to claim 13 · VvA.UU <'v_ ^ * t * ·