CA1181768A - Halogenated esters - Google Patents

Abstract

ABSTRACT

This invention relates to novel esters, useful as insecticides, of formula:- where R1 and R2 are methyl, halomethyl or halo; X is oxygen, sulphur, sulphonyl or NR4 where R4 is hydrogen, alkyl or carboxylic acyl; R3 is alkyl, alkenyl or benzyl and additionally R3 may be hydrogen when X is NR4; m=0 or 1 and n=1 to 4. The compounds may be prepared by esterification process from the corresponding benzyl alcohols which are also new compounds.
e

Description

This invention rela-tes -to novel cyclopropane derivatives useful as insecticides, to processes for their preparation, to compositions comprisi~g them and to methods of combat-ting insect and similar inverte~rate pests using them.
Cer-tain naturally occurring esters of cyclopropane carboxylic acids have long been known to possess insecticidal properties, but these compounds have been too easily degraded by ultra violet light to be of much use in agriculture. Several groups of synthetic compounds based on cyclopropane carboxylic acids (for example those disclosed in British patent specifications nos. 1,243,8~8 and 1,413,4~1) have heen evaluated in an attempt to di~cover compounds o sufficient light stability for use as general agricultural insecticides.
A particularly useful group of such compounds is that disclosed in British patent specification no. 2,000,76~ and U.S. patent no. 4,183,948. These compounds combine good light stability with excellent contact and residual insecticidal properties, but, in common with the compounds described in British patent specifications 1~243,858 and 1,413,491, they possess ~ittle or no fumigant activity. A
further group of compounds, halobenæyl esters of 3-(2~2-dihalovinyl)-2,2-dimethylcyclopropane carboxylic acids, is described in U.S. patent 4,183,950 as having insecticidal properties but there is no indication that the compounds possess fumigant activity.
The present invention relates to certain novel benzyl esters of 3-(2,2~dihalovinyl)-2,2-dimethylcyclopropane carboxylic acids and 3-(2-halo(or trifluoromethyl)-3,3,3-trifluoropropenyl)-2,2-dimethylcyclopropane carboxylic acids with an ext~emely high level of insecticidal and acaricidal activity which may be used not only as contact or residual insecticides but also as fumlgant insecticides.

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~ ccordingly khis inven-tion provides compounds of formula:-Rl C =-CH - CH-- ~ H - C - O - CH2 ~ ~ (X)m-R3 R~ CH3 ~I3 (IA) wherein Rl and R2 are each selected from methyl, halomethyl, and halo; X is oxygen, sulphur, sulphonyl or a group ~R4 where R4 represents hydrogen, lower alkyl or lower carboxylic acyl; R3 is lower alXyl, lower alkenyl or benzyl, and additionally R3 may be hydrogen when X is a group NR4; m has the value zero o:c one, and n has a value rom one to four.
The term "lower" is used herein in relation to "alXyl", "alXenyl" and "carboxylic acyl" groups to indicate such groups cc~ntaining up to six carbon a-toms, although such groups containing up to four carbon atoms are genera:Lly preferred.
In a preferred aspect the invention provides compounds of formula:-f ,C~ ~ F

(IB) ~B1768 wherein R~ and R2 are both mq-thyl, chloro or bromo, or one oE Rl and R2 is fluoro or chloro and the other is trifluoromethyl, and R3 is al'.cyl of up to four carbon atoms, alkenyl of from three to five carbon atoms, ethoxy, methoxy, allyloxy, benzyl, amino or acetamido. ~longst this group of compounds there especially preferred those wherein Rl and R2 are both chloro, or one of ~1 and R2 is chloro and the other is trifllloromethyl, and R is methyl, ethyl, allyl, methoxy, ethoxy, allyloxy, ethylthio or ethanesulphonyl. R is preferably in the 4- position with respect to the cyclopropane ester group.
Particular compounds according to the invention as defined by Eormula IA above include those set out in Table I herein in which the meanings or Rl, R2 and R are g.iven for each compound. ~

~ 4 --TABLE I

___~_, Compound 1 2 No . R R R
_ . _.. _ , _ __ ._ 1 CF3 Cl 4-CH3

2 CF3 Cl 4-SC2H5

3 Cl Cl 4-CE~

4 CF3 Cl 2 2 5 CF3 Cl 4-OCH3 6 CF3 Cl 2-CH3 7 CF3 Cl 4-OC2H5 : 8 Cl Cl ~-OC2H5 9 Cl Cl 4-C2H5 CF3 Cl 4-C H

11 Cl Cl 4-OCH3 12 Cl Cl 4-CH CH=CH

13 CF3 Cl 4-CH CH=CH

. 14 Cl Cl 4 O-~l CE=CU

61~

, T~BLE I (con-tinued) _ ;, .

Compound 1 2 No. R R R
_ ._ _ ~

CF3 . Cl 4-ll-C H

16 CF3 Cl 4-OCH CH=CH

17 CF3 Cl 3-CH

18 Cl Cl 3-CH3 19 CF3 Cl 4-n-C3H7 CF3 Cl 4-CH CH=C~CH ) 21 CF3 Cl 4-CH CH=CHCH

22 CF3 Cl 2 6 5 . 24 CF3 F 4-~(CH3)COC~I3 CF3 F 4-~(C2H5)3 26 Br Bx 4-OCH3 . 28 CH CH 2 2 76~3 T~BLE I ~ continued ) Compound 1 R2 R

~ ._ , , , CF3 F 4 ~ rCH

31 CF3 F 4-CH CH=CH

32 Br Br 4-CH C~l-CH

/

.. . . . _ _ _ _ _ .

6~

Further compounds accordiny to the invention include those of formula I above in which n is an integer or less than 4. Examples of such compounds are set out in Table Il below.

TABLE IX

.
_ _. _ _ _ _ Compound 1 2 ~ (Y ~ IY
No. R R

.~ 34 CF3 1 ~ H2CH=CH2 ~ 35 ~ CF ~ I ~ ~ H2CH=CH~¦

It will be appreciated by those sXilled in the art that the compounds represented by formula I are capable of existing in various geometrical and stereoisomeric forms~
Thus there may be cis and trans isomers arising from the substitution pattern of the cyclopropane ring, and E- and Z-isomer~s arising from the substituted vinyl group l.~en R is not identical with R . In addition two of the three carbon atoms of the cyclopropane are capable of existincJ in either R- or S-configurations since they are as~nmetrically substituted.

~18176B
.

Within the group of compounds represented by Formula I the cis isomers usually have better insecticidal properties than the trans isomers or the mixture of cis and trans .isomers; the (~)-cls isomers being particularly preferrecl.
A particularly useful single isorner of a cornpound according to the invention is the 4-methyltetrafluorobenzyl ', ester of (~)-cis-3-(Z-2-chloro-3,3,3-trichloroprop-l en-yl)-2,2-dimethylcyclopropane carboxylic acid, which is believed to have the (lR,3R) configuration in the cyclopropane ring.
The compounds of the invention accordinq to Formula I
are esters and may be prepared by conventional esterification processes, of s~hich the following are examples.
(a) An acid of formula:-O

R C--CH - CH - ~ H C Q (II) 2 /C\
R CH CH

where Q represents the hydroxy group and R and R have any of the meanings given hereinabove, may be reacted directly with an alcohol of formula:-F

HO - CH - ~ (III) (X) -R3 m ~8~8 _ 9 _ ~ I
where ~, R3,n and m have any of the meaninys yiven hereinabove, the reaction preferably taking place in the presence of an acid catalyst, for example, dry hydrogen chloride.
(b) An acid halide of formula II where Q repre~ents a halogen atom, preerably a chlorine atom, and Rl and R2 have any of the meanings given hereinabove, may be reacted with an alcohol of formula III, the reaction preferably takiny place in the presence or a base, for example, pyridine, alkali metal hydroxide or carbonate, or alkali metal alko~ide.
(c) An acid of formula II where Q represents the hydroxy group or, preerably, an alkali metal salt thereof, may ba reacted with halide of formula:-(X)m-R

where Ql represents a halogen atom, preferably the bromine or chlorine atom, X, R3, m and n have any of the meanings given hereinabove, or with the quaternary ammonium salts derived from such halides with tertiary amines, for example pyridine, or trialXyl amines such as triPthylamine.
(d) A lower alXyl ester of formula (II) where Q represents a lower alkoxy group containing up to six carbon atoms, preferably the methoxy or ethoxy group, and R1 and R2 have any of the meanings given hereinabove, is heated with an alcohol of formula III to effect a transesterification reaction. Preferably the process is performed in the presence of a suitable catalyst, for example, an alkall metal alkoxide, such as sodium methoxide, or an alkyla-ted titanium derivative, such as tetramethyl titanate.

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All of the~e conventional processes for the preparation oE esters may be carried out using solvents and diluents for the various reactants where appropriate, and may be accelerated or lead to higher yields of product when performed at elevated ternperatures or in the presence of appropriate catalysts, for example phase-transfer catalvsts.
The preparation of individual isomers may be carried out in the same manner but commencing from the corres-ponding individual isomers o ccmpounds o formula II.These may be obtained by conventional isomer separation - techniques from mixtures of isomers. Thus cis and trans isomers rnay be separated by fractional crystallisation of the carboxylic acids or salts thereof, whilst the various optically active species may be obtained by fractional i crystallisation of salts of the acids with op-tically active amines, followed by regeneration of the optically pure acid. The optically pure isomeric form of the acid (or its equivalent acid chloride or ester) may then be reacted with the appropriat:e alcohol to produce a comyound o formula I
in the form oi- an individually pure isomer thereof.
The preparation of the compounds of formula II wherein Q is hydroxy, alkoxy or halo, and Rl and R2 are as defined hereillabove, useful as intermediates in the preparation of the compounds of the invention, is fully described in British Patent Specification 2,000,764 and in U.S. patent no. 4,183,948, or British Patent Specification 1,413,491.
The compounds of formulae III and IV are believed not to have been described before. In a further aspect therefore the invention provides compounds o formulae III
and IV wherein X, R3, m and n have any of the meanings given for the corresponding compounds of formula I, and where Ql (in formula IV) is chloro or bromo.

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Pre~erred cornpounds of formulae III and IV are those corresponding to the compouncls set out in Table I.
I~e compounds of formula III may be prepared by different processes depencling upon the nature of the substituents in the berlzene ring. Thus for alkyl- or alkenyl- substituted compounds of formula III where R3 is alkyl and m is zero the appropriately substituted alkyl-or alkenyl- fluorobenzene may be carboxylated (ror example by the use of an organometallic reagent such as alkyl lithium, followed by decomposition of the reaction product with carbon dioxide) and subsequent reduction to the alcohol, using an appropriate reducing reagent, for example, lithium aluminium hydride.
The alkyl~ or alkenyl- substituted fluorobenzenes used as starting materi.als in this sequenee may be prepared by ~he alkylation of the appropriate fluorobenzenes using organometallic reagents such as alkyl lithium, and decomposing the reaction products with alkyl or alkenyl halides.
Alternatively the fluorobenzenes may be carboxylated first, and the resultant fluorobenzoic acids reduced to the benzyl alcohol which is then alkylated or alkenylated in a protected form (for example as the tetrahydropyranyl ether) using alkyll.ithium followed by reaction with an alkyl or 2S alkenyl halide.
All of these pxocesses are illustrated in the following scheme.

_ 12 ~

e~ 2. C0,, / ~C0 ~} LiAlHD~ ~ ~CH2CEI
F F F F F F

¦ 1. Li~3u ~¦~ 2. CEl3I [~ ICl CH3~ ~--CH2~>

1. LiBu 1. LiBu .~ ,2 . C2 ~ 2. ~CH3) C=CE~CH2Br F F
C~3 ~C02H (CH3) 2C=CHCH2 ~=~ 2(}~
F F

LiAI.H ~I CH 30H/HC 1 3 ~CH2oH (CH3) 2CH=C~ICH2 ~ 20H
F F F F

The compounds of formula III wherein X is sulphur or oxygen, may be prepared by displacement of halogen, e.gO
fluorine, from an appropria-tely substituted fluorobenzyl alcohol, or the tetrahydropyranyl ether -thereof. The following scheme illustrates the reactions used -to prepare a number of compounds of formula III.

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F F F F
~ C;2H5Na ~
F~CH20H C2H--5 OH ~----) C2H50~ 2 F F . F F

[3 1 HCl O

F F - F F
1 0 CH 30N a/CH 30H /~
> CH2 ~ ) ~ 3 < \)C}I20H
~=~ 0 2 . CH 30H/E~Cl \~/
F E' F F

C2 H5 SWa pyri dine C2H5 5 ~ CH2 _~ ) C2 H5 5 ~3CE20H
F F F F

C~I3C02~J

,~; ~\ CH 30H/HCl F F
C2H~S2~ CH2 \ ~ - ~ C2EI5SO~ CE~20 F F F F

L81'7613 -- 1~

Simi.larl.y -the compounds of formula III where X
represents a group of formula WR (where R is as - defined hereinbefore) may also be ob-tained from the corresponding fluorobenzyl alcohol. ~le followiny scheme illustrates the reactions involved in preparing some of these compounds.

HoCH2 ~ . Q 2 ~

1 NaNH / NH

NaNH2/NE13 2 . H 20/H
~ , EIOCH 2 _~H 2 ~ r OC'I 2 `--F F

(CH3CO) 2 /

HOCH ~NE~COCH3 ~ ~ OCH2 ~ NHCOCH3 F F
F F

CH3I/~aH

HOCH2--~ N /7 / CH~OH/fic~ / 3 F F CH3 C-;13 ~ ~8~'7~;~

In an alternative process cornpounds of formula I where X
represents a group of formula ~R twhere R is a lower carboxylic acyl group) may be obtainecl by acylation (e.g.
by reaction with the appropriate acyl chloride) of the corresponding compound where R is hydrogen.
Compounds of formula IV may be prepared by con-tac-tiny a compound of formula CH

( X ) --~
m with a source of positive halogenl such as an N-chloro- or N-bromoimide, for example, N-chlorosuccinimide and ~-bromosuccinimide.
When the processes for preparing the compounds ofFormula I are performed using intermediates which are themselves mixtures of isomers the products obtained will also be mixtures of isomers. Thus, the product would be a mixture of (*~cis and (~)-trans isomers (perhaps wit:h one form predominating~ if the intermediate acid or acid derivative was used in the form of a mixture of (-~)-cls and ~ trans isomers. If a single isomer, of the acid, e.g.
the (+)-cis isomer with _-configuration in the 2-chloro-3,3,3-trifluoropropenyl group, was used, the product would also be the single isomer of that stereochemical configuration, or a pair of isomers if there is an asymmetric carbon atom in the alcohol moiety.
In order to avoid confusion the products obtained by the processes described in the ~xamples herein are referred to as Products I to XXXVI, each product being defined in terms of isomeric composition with reference to the compounds of Tables I and III as follows:-~ ~ \
~ ~81t7~
- 16 ~

Product I 4-methylte-trafluorobenzyl 3-(2-chloro-3,3,3-trlfluoroprop-1-en-1-yl)-2,2-dimethylcyclopropane carboxyla-te (compound no. 1, Table I) consisting of 50% w/w of the (t)-cis isOMer and 50% w/w of the (~)-trans lsomer Product II 4-ethylthiotetra~luorobenzyl 3-(2-chloro-3,3,3-trifluoroprop-1-en-1-yl)-2,2-dimethylcyclopropane carboxylate (compound no.2, Table I) conslstin~ of 50% w/w of the ( )-cis isomer and 50~ w/w of the (~)-trans isomer Product III 4-methyltetrafluorobenzyl 3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane , 15 carboxylate (compound No.3, Table I) consisting of 50% w/w of the (l)-cis i.somer and 50% w/w of the (~-trans isomer Product IV 4-ethanesulphonyltetrafluorobenzyl 3-(2-chloro-3,3,3-t.ifluoroprop-1-en-1-yl)-2,2-dimethylcyclopropane carboxylate (compound noO 4, Table I) consisting of 50~ w/w of the (~)-cis isomer and 50~ w/w of the (~)-trans isomer ' Product V 4~-methoxytetrafluorobenzyl 3-(2-chloro-3,3,3-trifluoroprop-1-en-1-yl)-2,2-dimethylcyclopropane carboxylate (compound no. 5, Table I) consisting of 50% w/w or the (L)--cis isomer and 50~ w/w of the (~)-trans isomer.

8~l~6~

Prod~lct VI 2-me-thy].-te-trafl-lorobenzyl 3-(2-chloro-3,3,3-trifluoroprop-1-en--1-yl)-2,2-dimethylcyclopropane carboxylate (compound no. 6, Table I) consisting o:E
50% w/w of the (~)-cls isomer and 50%
w/w of the ~)-trans isorner.

Product VII 4-ethoxytetrafluorobenzyl 3-~-chloro~
3,3,3~trifluoroprop-1-en-1-yl)-2,2~
dimethylcyclopropane carboxylate (cornpound no. 7, Table I~ consistin~ of - 50% w/w of the (~)-cis isomer and 5Q%
w/w of the (~)-trans isomer.

Product VIII 4-e-thoxytetrafluorobenzyl 3-~2,2 dichlorovinyl)-2,2-dimethylcyclopropane carboxylate (compound no. i3, Table I) consisting of 50% w/w of the (~ cis isomer ; and 50% w/w of the (~)-trans isomer.

; Product IX 4-me-thyltetrafluorobenzyl (~)-cis-3-(2,2-dichlorov.inyl)~2,2-dimethylcyclopropane carboxylate (compound no.3, Table I) in its (+~-cis isomeric form.

Product X 4-methyltetrafluorobensyl 3-(2-chloro-3,3,3-trifluoroprop-1-en-1-yl)-2,2-dimethylcyclopropane carboxylate (compound no.l, Table I) in its (~)-cis isomeric form .

Product XI 4-ethyltetrafluorobenzyl 3-(2-chloro-3,3,3-trifluoroprop-l-en-l-yl~-2,2-dimethylcyclo-propane carboxylate (compound no.10, Table I) in i-ts (~ cis isomeric form.

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, Product XII 4-methoxyte-trafluorobenzyl 3~(2,2-dichloro-vinyl)2,2-dimethyleyclopropane carboxyla-te (compound no.ll, Table I) in its (+)-cis isomeric form.

Product XIII 4-n-butyltetrafluorobenzyl 3-(2 chloro-3,3,3-trifluoroprop-1-en-1-yl)-2,2 dimethylcyclopropane carboxylate (compound no.15, Table I) in its (~)-cis isomeric form.
.
Product XIV 4-allyloxytetra1uorobenzyl 3-(2-ehloro-3,3, 3-trifluoroprop-1-en-1-yl)-2,2-dimethyl-cyclopropane earboxylate (eompound no.l6, Table I) in its (+)-c1s isomeric form.

Product XV 4-methoxytetrafluorobenzyl 3-(2-chloro-3,3, 3-trifluoroprop-1-en-1-yl)-2,2-dimethyl-cyelopropane carboxylate (compound no.5, Table I) in its ~)-eis isomerie form.

Produet XVI 3-methyltetrafluorobenzyl 3-(2-chloro-3,3, 3-trifluoroprop 1-en-1-yl)-2,2-dimethyl-cyclopropane carboxylate (compound no.l7, Table I) in its (~)-cis isomeric form.

Product XVII 3-methyltetrafluorobenzyl 3-(2,2-dichloro-vinyl)-2,2-dimethylcyclopropane earboxylate (eompound no.l8, Table I) consisting of 50%
w/w of the (~)-els isomer and 50% w/w of the (~)-trans isomer.

Produet XVIII 4-allyltetrafluorobenzyl 3-(2-chloro-3,3,3-trifluoroprop-l-en-l-yl)-2,2-dimethylcyclo-propane carboxylate (compound no.13, Table I) in its (~) cis isorneric form~

Product XI~ 4-n-propyltetrafluorobenzyl 3-(2 chloro--3,3,3-tri~luoroprop-l-en-1-yl)-2,2-dlmethyl-cyclopropane carboxylate (compound no.l9, Table I) in it5 (~)-CiS isomeric ~oxm.

5 Product XX 4-allyltetrafluorobenzyl 3--(2,2-dlchloro-vinyl)-2,2-dimethylcyclopropane carboxylate (compound no.l2, Table I) consis-ting of 50%
w/w o the (~)~cis isomer and 50% w/w of the (~)-trans isomer.

lO Product XXI 4-(3-methylbut-2-en-l-yl)tetrafluorobenzyl 3-(2~chloro-3,3,3-trifluoroprop-l-en-l-yl)-2,2~dimethylcyclopropane carboxylate (compound no.20, Table I) in its (~)-cis isomeric form.

15 Product XXII 4-(but-2-en-l-yl)tetrafluorobenzyl 3-~2~
chloro-3,3,3-trifluoroprop-l-en-l-yl)-2,2-dimethylcyclopropane carboxylate (compound no. 21, Table I) in the form o a mixture of 50% of the E~butenyl and 50~ of the Z-butenyl isomeric forms of the (~)-cis isomeric form (with respect the c~clo-propane ring).

Product XXIII 4-allyl-2,6~difluoroben~yl 3-(2-chloro-3,3,3-trifluoroprop-l-en-l-yl~-2,2-dimethyl-cyclopropane carboxylate (compound no.35, Table II) in its (~)-C15 isomeric form.

Product XXIV 4-allyl-3,5-difluorobenzyl 3-(2-chloro-3,3,3-trifluoroprop-1-en-l~yl)-2,2-dimethyl-cyclopropane carboxylate (compound no~34, Table II) in its (~)-cis isomeric form~

~ 20 -Produc-t XXV 4-benzylte-trafluorobenzyl 3~(2-chloro-3,3,3-trifluoroprop-1-en-1-yl~-2,2-dimethylcyclopropane carboxylate (compound no.22, Table I) in its (~)~c:Ls isomeric form.

Produc-t XXVI 4-methoxytetrafluorobenzyl-3-(2,3,3,3-tetra-fluoroprop~l-en-yl)-2,2- dimethylcyclo-propane carboxylate (compound no.29, Table I) in its (~)-cis isomeric form.

Product XXVII 4-methoxytetrafluorobenzyl 3-(2,3,3,3-tetra~luoroprop-l-en-l-yl~-2,2-dimethyl-cyclopropane carboxylate (compound no. 29, Table I) in its ~ trans isomeric form.

Product XXVIII 4-methyltetrafluorobenzyl 3-(2,3,3,3-tetra-fluoroprop-1-en-yl)-7.,2-dimethylcyclo-propane carboxylate (compound no. 30, Table I) in its (~)-cis isomeric form.

Product XXIX 4-methyltetrafluorobenzyl 3-(2~3,3,3-tetra-fluoroprop-l-en-l-yl)-2,2-dimethylcyclo-propane carboxylate ~compound no. 30, Table I) in its (~)~trans isomeric form.

Product XXX 4-allyltetrafluorobenzyl chrysan-themate (compound no. 28, Table I) consisting or 50% w/w of the (~)-cis isomer and 50% w/w of the ~ trans isomer.

Produc-t XX~l 4~me-tho~y-2,6-diEluoroben~yl 3-(2-chloro-3,3,3-tri~luoroprop-1-en-l~yl)-2,2-dimethylcycloproparle carboxylate (compound no.36, Table IJ) in its (~)-cls isomeric form.

Product XXXII 4-allyltetrafluoro~enzyl 3-(~,3,3,3-tetra-fluoroprop-l-en-l-yl)-2,2-dime-thylcyclo-propane carboxylate (compound no. 31~
Table I) in its (~)-cis isomeric form.

10 Product XXXIII 4-allyltetra~luorobenzyl 3-(2,3,3,3-tetra-fluoroprop~l-en-l-yl)-2,2-dimethylcyclo-propane carboxylate (compound no. 31, Table I in its (i)-trans isomeric ~orm.

Product XXXIV 4-allyltetrafluoxoberlzyl 3-(2,2-dibromo-vinyl3-2,2-dimethylcyclopropane carboxylate (compound no. 32, Table I) in its (~3-cis isomeric form.

Product XXXV 4-aminotetrafluorobenzyl 3-~2,3,3,3-te-tra-fluoroprop-l-en-l-yl)-2,2-dimethylcyclo-propane carboxylate (compound no. 33, Table I) consistiny of 50% w/w of the (~
cis isom~r and 50% w/w of the (.)-trans isomer.

Product XXXVI 4-acetamidotetrafluorobenzyl 3-~2,3,3,3-tetrafluoroprop-1-en-1-yl)-2,2-dimethyl-cyclopropane carboxylate (compound no. 23, Table I3 consisting of 50~ w/w of the (')-cls isomer and 50% w/w of the (~)~t~ans isomer.

~8~7i~

~ le compounds of ormula I may be used to combat and control infestations of insect pests and also other invertebrate pests, or example, acarine pests. The insect and acarine pests which may be combatted and controlled by S the use of the invention compounds include those pests associated with agriculture (which term includes the growing of crops for fo~d and fibre products, horticulture and animal husbandry), forestry, the storage of products of vegetable ~rigin, such as fruit, grain and timber, and also those pests associated with the transmission of diseases of man and animals.
In order to apply the compounds to the locus of the pests they are usually formulated into compositions which include in addition to the insecticidally active ingredient or ingredients of formula I suitable inert diluent or carrier materials, and/or surface active agents. The compositions may also comprise another pesticidal material, for example another insecticide or acaricide, or a fungicide, or may also comprise a insecticide synergist, such as for e.xample dodecyl imidazole, safroxan, or piperonyl butoxide.
The compositions may be in the form of dusting powders wherein the active ingredient is mixed with a solid diluent or carrier, for example kaolin, bentoni-te, kieselguhr, or talc, or they may be in the form of granules, wherein the active ingredient is absorbed in a porous granular material for example pumice, gypsurn or corn cob. grits. Granules are particularly useful for combating soil borne insect pests, such as root worms of the genus Diabrotica, cutworms 30 (Agrotis spp.) and wireworms (Agr is spp . ) . Preferably, the granules contain from 1 to 2.5~ by weight o~ the active ingredient, which is absorbed onto the granule by, for example, spraying the granules with a solution of the active ingredient in a volatile solvent which is sub-sequently evaporated from the surface of the granules.Such solutions rnay contai.n other ingredients, for example a re in tc~ regulate the rate o~ release of the ac-tive ~l~8~768 ~ 23 -ingredien-t from the granules, or to help preverlt premature disintegration of -the granules. Granules may be applied to the soil either in a band between the ~urrows clefinin~ the crop rows, or broadcast, and may if desired be lightly incorporated in the soil, or they may be placed in the furrows themselves at the time of planting the crop.
Application of granules at a rate of from 5 to 25 lb/acre (approximately S to 25 kg/ha) is usually sufficient to control the pests, and a pxeferred rate is within the range 8 to 15 lb/acre tapproximately 8 to 15 Xg/ha) based on the active ingredient.
Alternatively the compositions may be in the form of liquid preparations to be used as dips or sprays, w~ich are generally aqueous dispersions or emulsions of the active ingredient in the presence of one or more known wetting agents, dispersing agents or emulsiEying agents ~surface active agents).
~ letting agents, dispersiny agents and emulsiying agents may be of the cationic, anionic or non-ionic type.
Suitable agents of the cationic t~pe include, for example, quaternary ammonium compounds, for example cetyltrimethyl ammonium bromide. Suitable agents of the anionic type include, for example, soaps, salts of aliphatic monoesters or sulphuric acid, for example sodium lauryl sulphate, salts of sulphonated aromatic compounds, for example sodium dodecylbenzenesulphonate, sodium, calcium or ammonium lignosulphonate, or butylnaphthalene sulphonate, and a mixture of the sodium salts of diisopropyl- and triiso-propylnaphthalene sulphonates. Suitable agents of the non-ionic type include, for example, the condensation productsof ethylene oxide with fatty alcohols such as oleyl alcohol or cetyl alcohol, or with alkyl phenols such as octyl phenol, nonyl phenol and octyl cresol. Other non-ionic agents are the partial esters derived from long chain fatty acids and hexitol anhydrides, the condensation products oE
the said partial esters with ethylene oxide, and the lecithins.

- 2~ -~ le compositions may be prepared by dissolving the active ingredient in a suitable solvent, for example, 2 Xetonic solvent such as diacetone alcohol, or an aromatic solvent such as trimethylbenzene and adding the mixture 50 obtained to water which may contain one or more known wetting, dispersing or ernulsifying agents. Other suitable organic solvents are dimethyl formamide, ethylene dichloride, isopropyl alcohol, propylene glycol and other glycols, diacetone alcohol, toluene, kerosene, white oil, methylnaphthalene, xylenes and trichloroethylene, ~-methyl-2-pyrrolidone and tetrahydro furfuryl alcohol (THFA).
~ he compositions to be used as sprays may also be in the form oP aerosols wherein the formulation is held in a container under pressure in the presence of a propellant lS such as fluorotrichloromethane Gr dichlorodifluoromethane.
The compositions which are to be used in the form of aqueous dispersions or emulsions are generally supplied in the form of a concen-trate containing a high proportion of the active ingredient or ingredients, the said concentrate to be diluted with water before use. These concentrates are often required to withstand storage for prolonged periods and after such storage, to be capable of dilution wi-~h water to form aqueous preparations which remain hornogenous for a sufficient time to enable them to be applied by conventional spray equipment. The concentrates may contain 10-85% by weight of the ac-tive ingredient or ingredients. When diluted to form aqueous preparations such preparations may contain varying amounts of the active ingredient depending upon the pu~pose for which they are to be used. For agricultural or horticultural purposes, an aqueous preparation containing between 0.0001% and 0.1% by weight of the active ingredient is particularly useful.
In use the compositions are applied to the pests, to the locus of the pests, to the habitat of the pests, or to growing plants liable to infestation by the pests, by any of the known means of applying pesticidal composi-tions, for example, by d~sting or spraying.

7~
- ~5 -The composi-tions of the invention are very toxic to wide varieties of insec-t and ot.her invertebrate pests, including, for example, the followin~:-Aphis fabae (aphids~
Megoura viceae (aphids) Aedes aegypti (mosquitoes) Dysdercus fasciatus (capsids) Musca domestica (houseflies) Pieris brassicae (white butterfly, larvae) Plutella maculipennis (diamond back month, larvae) Phaedon cochlear.iae (mustard beetle~
Telarius cinnabar1nus (carmine spider mi~e) Aonidiella spp. (scale insects) Trial_uroides spp. (white flies) Blattella germanica (cockroaches) -Spodoptera llttoralis (cotton leaf wGrm) Chortiocetes terminifer~ (locusts~
Dia rotica spp. (rootworms) Agro~is spp. (cutworms) The compounds of formula I and compositions comprising them have shown themselves to be particularly useful in controlling lepidopteran pests of cotton, for example Spodoptera spp. and Heliothis spp. The fumigant properties of thl compo-lnds enable them to be used to combat pests which .inhabit the soil, for example Diabrotica spp. They are also excellent knock down agents and as such may be used in conjun~tion with other insecticides to combat public health pests such as flies. They are also very useful in combatting insect and acarine pests which infest domestic an.imals, such as Lucilia sericata~ and ixodid .
ticks such as Boophilus spp., Ixodes spp., nblyomma spp., Rhipicephalus spp., and Dermaceutor spp. 'Fhey are effective in combatting both suscep-tible and resistant strains of these pests in their adult, larval and intermediate stages of growth, and may be applied to -tha in~ested host animal by topical, oral or parenteral adrninistra-tion.

~e ~ollowing Examples illustrate the various aspects of the invention.

~XAMPLE 1 This Example illustrates the insecticidal properties o the Procluc-ts I to XXXVI.
S The activity of the products was determlnecl using a variety of insect pests. The product was used in the form of liquid preparations containing 500, 100, 50 or ~5 parts per million (p.p.m.) by weight of the product. The preparations were made by dissolving the product in a mixture of solvents consisti.ng of 4 parts by volume o acetone and 1 part by volume of diacetone alcohol. The solutions were then diluted with water containing 0.01% by weight of a wetting agent sold under the trade name "LISSAPOL" NX until the liquid preparations contained the required concentration of the product. "Lissapol" is a Registered Trade Mark.
The test procedure adopted with regard to each pest wa~ basicall~ the same and comprised supporting a number of the pests on a medium which was usually a host plant or a foodstuff on which the pests feed, and treating either or both the pests and the medium with the preparations. The mortality of the pests was then assessed at periods usually varying from one to -three days after the treatment.
Details are given in Table III.
The results of the tests are given in Ta~le IV ~or each of the products I to XXXVI at the rate in parts per million given in the second column as a grading of mortality on a scale of 0-9 wherein ~ `
7~i~
~ 27 -0 represen-ts less than 10~ mortality 1 " from 10 to 19%
2 " " 20 to 29% "
3 .. ~ 30 to 39~ "
4 " ~ 40 to ~9% "
" ~ 50 to 59% "

6 " " ~0 to ~9% "

7 1. ~ 70 to 79% "

8 " " 80 to 89% "

9 " " 90 to 100% "

In Table IV -the pest organism used is designated by a letter code and the pest species, the support medium or food, and the type and duration of test is given in Tabl e III.

7~;~

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O ._ .,~ ¦
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~ O ~ ,1 1 O~ O ~ 13 3 ~ 1~ ~ ~
~:) H ~ C S~ ~1 t~l ¦
U~ ~ O ~ O
X ~) ~ rl :~ ~ ~ ~ m ~ ,~
H O-rl 0 5 h r~
H C.) E~
____ . . ._ ---- -- ----- ` 3 C~ ~ ~ Q~
, ~ ~ '~1 I ~ I ~ ~ ~ ,~
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V U ~) 3 ~n l~ ~1 ~ ~ O
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~n O ~ 0 ~ ~ ~ ~ ~
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o ~ ~ o 0 ~ ~ ~4 o 3 o ~n o ~ ~ 0 E 0 ~ .~ ~ ~ ~ u r"
u ~ ~ ~ ~ ~ ~ ~ o ~,~ ~ o u~ o o o ~1 ~ " s~ ~ s~ ~ ~ o u ~ ~ ra ~ ~ 1 s~
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TABLF. IV

. . PEST SPECIES

P RODIICT RATE MD SL PX ~

V 100 g 9 9 9 9 XII 100 9 9 9 8 g XIV 100 _ _ _ 0 9 TABLF: IV (continued) ___ I_ . ~. . ........ ... __ , PEST SPEC:[ES
__ _ _.
RATE
PRODUCT ( ppm ) MD SL PX SG DB
. . ___ __ __.__ XVII 50 . 9 9 9 9 9 X}~ 50 9 9 9 9 g XXV 500 0 9 g 9 9 XXVI 100 _ 9 9 9 XXVII 100 _ g 9 9 XXVIII100 _ 9 9 9 XXIX 100 _ 9 9 9 XXXV 100 ~ g 9 O 9 XXXVI 100 ~_ 6 O

~: i A dash (-) in Table IV above indi.cates that the Produc-t had not been tested aga;nst the particular pes-t species.
In further tests the products sho~e~l insecticlclal ac-tivity against a number oE other species. Thus for example Products II, III, V, XXIII, XXVII and XXX showecl good aphi.cidal properties agains-t Aphis fabae.
In Table V below the minimum concentration ~in parts per mi.llion) required to give 100% mor-tality of red spider mite adults (Tetrany~hus telarius, SM) on French bean leaves and plant.hoppers (Nilaparvata lugens, P~) on rice is given for several of the Produc-ts. A dash t-) in -this table indlcate~ that 100~ mortality was not obtained at the highest rate tested (usually 500 parts per million).

TABLE V

~ . _ . . .
¦ Ra-te (ppm) giving Rate (ppm) giving 100% mortality 100~ mortality Product Product SU . _ SM PH
__ _ . _ _ III 100 100 XVII _ 500 V 10.0 100 XVIII 50 50 X _ 500 XX 50 50 XI _ 100 XXI _ XII 500 500 XXII _ 50 XIII _ 500 XXIII 100 50 XIV ~ 500 XXIV _ 100 -_._. . _ EXP~MPLE 2 This Example illustra-tes the preparation of 2-methyl-3,4,5,6-tetrafluorobenzyl alcohol.
(a) Preparation of 2,3,4,5-tetrafluorotoluene.
A solution of n-butyllithium in hexane ~1.6M, 62.5 ml) was added dropwise to a well stirred solution of 1,2,3,4-tetrafluorobenzene ~15.0g) in dry tetrahydrofuran (150 ml) maintained at a temperature of -60 C under an atmosphere of dry argon. ~lhen the addition was complete the mixture was stirred at -45C for 2 hours and then methyl iodide (14.2g) was added dropwise whilst the temperature was kept at -45C. After a period of 30 minutes the mixture was allowed to warm to the ambient temperature, poured into distilled water and the mixture extracted with diethyl ether (2 x S0 ml), and the extracts dried over anhydrous magnesium sulpha'ce. After filtering the solution was concentrated by evaporation of the solvents at atmospheric pressure. The residual oil was distilled and the fraction boiling in the range 115-122C at atmospheric pressure 6.2 g) collected, identified by n.m.r. and gas chromato-graphic analysis as consisting of ca. 90% o~ the re~uired2,3,4,5-tetrafluorotoluene and ca. 10~ of 3,4,5,6- tetra-fluoro-1,2-xylene.
(b) Preparation of 3,4,5,6-tetrafluoro-2-toluic acid.
The product of step (a) above ~S~5g) was mixed with diethyl ether (35 ml), the mixture cooled to -70C, and maintained at this temperature whilst a solution of n-butyllithium in h-hexane ~1.6M, 21 ml) was slowly added.
The mixture was stirred for a period of 1 hour during which time a fine white precipi-tate was formed. Dry carbon dioxide gas was then passed into the mixture for 30 minutes whilst the temperature was maintained within the ran~e -70C to -40C, and continued to be passed in thereafter whilst the mixture was allowed to warm to the ambient -tempera-ture.

' Af-ter acidifying with dil~te hydrochloric acid (6N, 40 ml) the organic phase was separated, washed with water ~nd dried over anhydrous magnesium sulpha-te. Af-ter evaporation of the solvents under reduced pressure -the residual oil (which from n.m.r. analysis was shown to be an approximately 1:1 mixture of the desired product and pentanoic acid) was carefully distilled under reduced pressure (water pump) using a Kugelrohr apparatus, and the fraction which solidified on cooliny collected and 10recrystallised from toluene to yield 3,4,5,6-tetrafluoro-2-toluic acid, m.p. 165C (0.65g), identified by infra red and nuclear mag~netic resonance spectroscopy.
~c) Preparation of 2-methyl-3,4,5,6-tetrafluorobenzyl alcohol.
lS3,4,5,6-tetrafluoro-2-toluic acid (500 mg) was dissolved in dry diethyl ether (5.0 mlj added dropwise to a suspension of lithium aluminium hydride (100 mg) in dry ether (10 ml) under an argon atmosphere at th~ ambient temperature. When the addition was complete and the effervescence had subsided the mixture was heated at the reflux temperature for a period of 1 hour. After allowin~
the mixture to cool to the ambient temperature water (10 ml) was cautiously added and the resultan-t mixture extracted with diethyl ether (2 x 20 ml), the extracts washed with water and dried over anhydrous magnesium sulphate. After filtration the filtrate was concentrated by evaporation of the solvent. The residual low melting solid was recrystallised from petroleum ether (boiling range 40-60C) to yield 2-methyl-3,4,5,6-tetrafluoro-benzyl alcohol (200 mg). ~.m.r.('H(ppm)CDCl ): 2.18(s,1H); 2.32~t,3H); 4.86(s,2H).

The procedures of Example 2 were used -to prepare various b~nzyl alcohols from tetxafluorobenzenes via -the appropriate benzoic acids.
(a) B~ the procedure set out ln paragraph (a) of Example 2 (but using the appropriate lithium derivatives) the following conversions were effected:
(a~(i) 1,2~4,5-tetrafluoroben~ene to 2,3,5,6-te-trafluoro-toluene (b.p. 117-121C, contaminated with ca 5 2,3,5,6-tetraflùoroxylene).
N.m.r. ( H(ppm)CDCl ): 2.28(t,3H); 6.58-6.94 (m,lH). Infra red (liquid film): 3075, 1645, 151~, 1255, 1165 cm (ii) 1,2,4,5-tetrafluorobenzene to ethyl-2,3,5,6-tetra-fluorobenzene (b.p. 128-134C).
N.m.r. ( H(ppm)CDCl ): 1.20 (t,3H), 2.72 (q,2H);
Infra red (liquid film): 3075, 1650, 1510, 1250 cm (iii) 1,2,4,5-tetrafluorobenzene to n-propyl-2,3,5,6-tetrclfluoxobenzene (b.p. 142-146C).
N.m.r. ( H(ppm)CDCl ): 0.96 ~t,3H); 1.64 (q,2H);
2.74 (t,2H); 6.74-7.08 (m,lH) Infra red (liquid film): 3075, 1655, 1495, 1255 cm (iv) 1,~,4,5-tetrafluorobenzene to benzyl-2,3,5,6-tetra-fluorobenzene (m.p. 38-40C) N.m.r. ~ ~(ppm)CDCl ): 4.02 (s,2H); 6~68-7O08 (m,lH); 7.20 (s,5H).
Infra red (liquid paraffin): 3080, 1645, 1605, 1500 1250 cm (y) 1,2,4,5--tetrafluorobenzene to allyl-2,3,5,6-tetra-fluoroben~.ene :l~l8~

N.m.r. ( H(ppm)CDCl ): 3.40 (m,2H); 4.78-5.18 (m,2~); 5.60-6.05 (m,lH); 6.60-7.00 (m,lH).
Infra red (liquid fllm): 3080, 1640, 1500, 1250, 1170, 850 c~l (b) By the use o~ the procedure se-t out in paragraph tb) of ExampLe 2 the following benzoic acids were obtained from the appropriate precursar as follows.

ti) 4-methyl-2,3,5,6-tetrafluorobenzoic acid t~rom 2,3,5,6-tetrafluorotoluene) - m.p. 170C.
~.m.r. ( H(ppm)CDCl ): 2.44(t,3H); 11.56 (s,lH) Infra red tliquid paraf~in): 3300-2450, 1710, 1650, 1460, 1070 cm tii) 4-ethyl-2,3,5,6-tetrafluorobenzoic acid (from ethyl-2,3,5,6-tetrafluorobenzene) - m.p. 92-93C.
N.m.r. ( H(ppm)CDC1 ): 1.24 (t,3H); 2.80 tq,2H3 13.30 (s,lH).
Infra red tliquid paraffin): 3300-2450, 1710, 1650, 1485, 1460, 965 cm (iii) 4-n-propyl-2,3,5,6-tetrafluorobenzoic acid lfrom n-propyl 2i3,5,6-tetrafluorobenzene) - m.p. 65-68C.
N.m.r. ( H(ppm)CDCl ): 0.98 tt,3H); 1.68 tq,2H) 2.76 (t,2H); 11,34 (s,lH) Infra red (liquid paraffin): 3300-2450, 1710, 1650, 1485, 1450 cm (iv) 4-benzyl-2,3,5,6-tetrafluorobenzoic acid (from benzyl-2i3,5,6-tetrafluorobenzene) - m.p. 161-164~C
N.m.r. ( H(ppm)CDCl ): 4.06 ts,2~); 7.22 ts,5H)

10.06 ts,lH) Infra red tliquid paraffin): 3300-2450, 1705, 1650, 1485, 1005 cm ~8~76~3 ~v) 4-allyl-2,3,5,6 te-trafluorobenzoic acid tfrom allyl-2,3,5,6-tetrafluo obenzene) - m.p. 88-90C
N.m.r. ( El(ppm)CDCl ): 3.50 (m,2H); 4.95-5.20 ~rn,2H); 5.60-6.08 (rn,lH); 1l.82 ts,lH) Infra red tliquid paraffin): 3300-2300, 1700, 1650, 1470, 1410, 1290, 1240, 980 cm (c) By the procedure set out in paragraph tc) of Example 2 the benzyl alcohols were obtained by reduction of the appropriate acids as follows:

ti) 4-methyl-2,3,5,6-tetrafluorobenzyl alcohol tfrom 4-methyl-2,3,5,6-tetrafluorobenzoic acid) -m.p. 61-62~C.
N.m.r. t ~l(ppm)CDCl ): 2.24 (t,3H); 2.06 (s,lH) 4.82 (s,2H) Infra red (liquid paraffin): 3300-1~60, 1460, 1280, 1020 cm (ii) 4-ethyl-2,3,5,6-tetra1uorobenzyl alcohol (from 4-ethyl-2,3,5,6-tetrafluorobenzoic acid) - m.p. 36-37C
N.m.r. ( H(ppm)CDCl ): 1.22 (t,3H); 2.06 (s,lH);
2.76 (q,2~); 4.78 (s,~) Infra red (liquid paraffin): 3300, 1660, 1490, 1465, 1280 cm (iii) 4-n-propyl-2,3,5,6-tetrafluorobenzyl alcohol (from 4-n-propyl~2,3,5,6-tetrafluorobenzoic acid).
N.m.r. ( ~(ppm)CDCl ): 0.94 ~t,3H); 1.60 (~,2H);
2.12 (s,lH); 2.66 (t,2H);
4.70 (s,21.) Infra red (liquid film): 3350, 1660, 1485, 1280, 1015 cm 7Ei~3 .

(iv) 4-benzyl-2,3,5,6-tetraEluc)robenzyl alcohol (from 4-benzyl-2,3,5,6-te-trafluorobenzoic acid) - m.p. 72-7~C.
NOmAr. (lH(ppm)CDC13): 2.00 (s,lH); 4.04 (s,2H);
4.78 (s,2H); 7.22 ~s,SH) Infra red (liquid parafin): 3300, 1655, 1485, 1010 cm~l tv) 4-a11~1-2,3,5,6-tetra1uorobenzyl alc~hol (from 4-allyl-2,3,5,6-tetrafluorobenzoic acid) N.m.r. (lH(ppm)CDC13): 2.42 (s,lH); 3,35 (m,2H) 4.68 (m,2H); 4.82 5.10 (m,~H); 5.55-5.98 (m,lH) Inra red (liquid filrn): 3600-3100, 2950, 1640, 1490 1300, 1270, 1020, 860 cm~

!` This Example illustrates the preparation oE 4-methoxy-2,3,5,6-tetrafluorobenzyl alcohol.
P~ntafluorobenzyl alcohol (1.98 g) was added to a stirred solution of sodium methoxide (obtained by dissolving sodium (0.4 g) in methyl alcohol (10 ml) at the ambient temperature, and the mixture heated at the reflux temperature for 3.5 hours. After cooling the mixture, the solvent was removed by evapora~ion under reduced pressure and the residue partitioned between water and diethyl ether. After separating the ethereal layer and washing with water, it was dried over ~anhydrous magnesium sulphate and concentrated by evaporation of the solvent under reduced pressure to yield 4-methoxy 2,3,5,6-tetrafluoro-benzyl alcohol (1.8 g), identical with the product of Example 5.
Infra red (liquid film): 3600-3100, 2950, 1650, 1500, 1200, 1130, 1040, 1000, 930cm~l `` ` ` ~8i~7~1 - 3~ -EX~MPLE 5 This Example illustrates the preparation of 4~methoxy-2,3,5,6-tetrafluorobenzyl alcohol.
(a) Preparatlon of pentafluorobenzyl te-trahydropyran-2-yl ether.
A mixture of pentafluorobenzyl alcohol (17.87 g) 2,3-dihydro-4H-pyran (8.3 g), dry diethyl ether (100 ml) and concentrated hydrochloric acid (0.2 ml) was stirred at t~e ambient temperature for 4 hours, after which the mixture was washed with water, dried over anhydrous magnesium sulphate and concantrated by evaporation under reduced pressure. The residual oil was identified by infra red spectroscopy as pentafluorobenzyl tetrahydropyran-2-yl ether.
(b) Preparation of 4-methoxy-2-3,5,6-tetrafluorobenzyl tetrahydropyran-2-yl ether.
; To a mixture of freshly preparèd dry sodium methoxide ~obtained by dissolving sodium metal (0.~6 g) in dry methyl alcohol and evaporating to dryness) and dry pyridine (25 ml) was added, dropwise with vigorous stirring, a solution of pentafluorobenzyl tetrahydropyran-2-yl ether (2.82 g) in dry pyridine (20 ml), and the resultant mixture stirred for 3.5 hours and then allowed to stand at the ambient temperature for 16 hours. The mixture was poured into water, acidified with dilute hydrochloric acid, and extracted with chloroform. After drving the extracts with anhydrous magnesium sulphate, the solvents were evaporated under reduced pressure and the residual pressure and the residual oil identified by n.m~r. and infra red spectroscopy as 4-methoxy-2,3,5,6-tetrafluorobenzyl tetra-hydropyran-2-yl ether.
(c) Preparation of 4-methoxy-2,3,5,6-tetrafluorobenzyl alcohol~

3L 181 ;~6~3 ~le procluct of step (b) above (~.8 g) was dissovlecl in a mixture of methyl a]cohol (50 ml) and concentrated hydrochloric acid (4 ml) and the resultant mixture heated at reflux temperature or a period of 5 hours. After removal of the me-thanol by evaporation under reduced pressure the residual oil was parti-tioned between water and chloroform. ~le chloroform layer was separated, washed with water, dried over anhydrous magnesium sulphate, and concentrated by evaporation of the chloroform to yield 4~
methoxy~2,3,5,6~tetrafluorobenzyl alcohol as a colourless oil. The identity was confirmed by n.m.r. and infra red spectroscopy.
N.m.r. ( H(ppm)CDCl ): 2.63 (s,lH); 4.02 (d,3H);
4.65 (d,2H).

1~ By the p~ocedure illustrated in Example 5 4-ethylthio-2,3,5,6-tetrafluorobenzyl alcohol (b.p. 120C/0.05 mm ~g.
Kugelrohr apparatus) was obtained from pentafluorobenzyl tetrahydropyran-2 yl ether via 4-ethylthio-2,3,5,~-tetra-fluorobenzyl tetrahydropyran-2-~71 ether.
2~ N.m.r. ( H(ppm)CDCl ): 1.24 (t,3H); 2.70 (s,lH);
2.94 (q,2H); 4..73 (s,~H).

.

This Example illustrates the preparatlon of 4-ethane-sulphonyl-2,3,5,6-tetrafluorobenzyl alcohol.
A mixture of 4 ethylthiotetrafluorobenzyl tetrahydropyran-2-yl ether (1.4 g), hydrogen peroxide (30% w/v, 100 vol, 4 ml) and glacial acetic acid (25 ml) was heated at the reflux temperature for 6 hours, kep-t at the ambient -temperature for 16 hours and then heated a-t the re~lux temperature for 4 hours. The mix-ture was cooled, diluted with water, and extracted wi-th chloroform.

8~i8 - ~o Ihe extracts were was~ed with saturated sodiurn blcarbonate solution, dried over anhydrous macJnesium sulphate and concentrated by evaporation oE the solvent under reduced pressure. The residual oil (believed to be 4-ethane-sulphonyltetrafluorobenzyl tetrahydropyran-2 yl ether) was dissolved in a mixture oE methanol (30 ml) and concentrated hydrochloric acid (3.0 ml) and heated at the re1ux temperature for 5 hours. After removal o~ the volatile portion by evaporation under reduced pressure the residue was partitioned between water and chloroform, the chloroform layer washed with water, dried over anhydrous magnesium sulphate and concentrated under reduced pressure to yi~ld 4-ethanesulphonyltetrafluorobenzyl alcohol, identified by infra red and n.m.r. spectroscopy.
N.m.r. (lEI(ppm)CDC13): 1.40 (t,3H); 3.21 ts,lH);
3.42 (q,2H); 4.85 (s,2H).

EX~MPLE 8 The proc~sdure of Example 4 was u~ecl to prepare 4-allyloxy-2,3,5,6-tetrafluorobenzyl alcohol by the reaction o~ pentafluorobenzyl alcohol with a solution o~ sodium in allyl alcohol.
N.m.r. (lH(ppm~CDC13): 3.20 (s,lH); 4.70 (t,4H);
5.18-5.54 (m,2H); 5.~1-6.22 (m,lH~.
Infra red (liquid film): 3600-3100, 2950, 1650, 1495, 1420, 1140, 1030, 980, 930 cm~

This Example illustrates the preparation of 4-(3-methyl-but-2-en-1-yl)-2,3,5,6-tetrafluorobenzyl alcohol.
(a) 2,3,5,6-tetra~luorobenzyl alcohol.
Lithium aluminium hydride (4.6 g) was adcled in small portïons to a stirred solution of 2,3,5,6-tetrafluoro-benzoic acid (30.0 g) in dry e-ther (600 ml) at the ambient temperature, and stirring continued ~or a pexiod of 3 hours. Af-ter clecomposition of the excess lithium al~lminium hydride with ethyl alcohol, wa-ter was added in excess and the ethexeal phase separated, washed with water, and concentrated to yield crude 2,3,5,6-te-trafluorobenzyl alcohol (13.0 g) as a colourless oil.
N.m.r. ( H(ppm)CDCl ): 3.44 (s,lH); 4.72 (t,2~1);
6.80-7.40 (m,lH) Infra red (liquid film): 3600-3100, 2950, 1510, 1260, 1180, ~050, 870 cm (b) 2,3,5,6-tetrafluorobenzyl tetrahydropyranyl ether was prepared from the product of step (a) by the methocl set out in step (a~ of Example 5.
N.m.r. ( H(ppm)CDCl 3: 1.30-2.10 (m,6H), 3.40-4.10 ~m,2H), 4.45-5.10 (m,3H); 6.86-7.32 (m,lH) Infra red (liquid film): 2950, 1510, 1270, 1175, 1120, 1030 970, 870 cm (c) 4-(3-methylbut-2-en-1-yl)-2,3,5,6-tetrafluorobenzyl tetrahydropyranyl ether.
The product from step (b) (0.84 g) was dissolved in dry tetrahydro~uran and then stirred solution cooled to -70C
under an argon atmosphere. Lithium butyl (2.2 ml of a 1.6M) solution in n hexane was added slowly, after which the resultant mixture was stirred for 45 minutes at -70C. 1-bromo-3-me-thylbut-2-ene (0.50 ml of a freshly distilled sample) was added slowly and after a further 30 minutes stirring at -70C the mixture was allowed to attain the ambient temperature tca. 25~C). ~ater was carefully added to the mixture which was then acidified with d-lute hydro-chloric acid. After }ceepin~ for 18 hours the ethereal phase was separated ~rom the mixture, the aqueous phase extracted with diethyl ether and the extrac-t combined with -the ethereal phase. After washing with water and drying over anhydrous magn~sium sulphate the ethereal solution was ~8~7~i8 concentrated by evaporation of the solvents under reduced pressure and the residual oil (0.85 g) identi~ied as a mixture o the required product with the star-~ing material.
Infra red (liquid film): 2950, 1510, 1490, 1270, 117$, 1120, 1030, 970, 970 cm (d) 4-(3-methylbut-2-en-1-yl)-2,3,5,6-tetrafluorobenzyl alcohol was ob-tained (in mixture with 2,3,4,5-tetrafluoro-benzyl alcohol) by sub~ecting the mixture prepared in st~p (c) to the method of step (c) of Example 5. 'Fhe required product was separated from the mixture by thick layer preparative chromatography using 2 r~ thick silica gel plates and ether/chloroform (1:10 by volume) as eluent.
.m.r. ( H(ppm)CDCl ): 1.72 (d,6H; 2.72 (m,lH);
3.41 (m,2H); 4.80 (s,2H);
5.07-5.35 (m,lH) Infra red (liquid film):-3600-3100, 2990, 1500, 1260, 1180 1090, 870 cm The procedures o~ Example 9 were used to prepare other 4-alkenylfluorobenzyl alcohols via their tetrahydropyranyl ethers as follows:

(i) 4-(but-3~en-1-yl)-2,3,5,6-tetrafluorobenzyl ~lcoholO
~J.m.r. ( H(ppmjCDCl ): 1.48-1.78 (m,3H); 2.60 (s,lH) 3.40 (m,2~); 4.70 (s,2H); 5.25-5.75 (m,2H) Infra red (liquid film): 3600-3100, 1495, 1275, 1030 975, 860 cm (ii) 4-(but-3-en-1-yl)-2,4,5,6-tetrafluorobenzyl tetra-hydropyranyl ether (mixture with 2,3,5,6-tetrafluoro-benzyl -tetrahydropyranyl ether).

6~3 ~ 43 -Infra red (liquid film): 2950, 1505, 1490, 1260, 120~, 1120, 1030, 97~, 910, 870 cm (iii) 4-allyl~3,5 difluorobenzyl alcohol N.m.r. ( H(ppm)CDCl ): 2.10 (m,lH); 3.~0 (m,2H);
4.62 (s,2H); 4.90-5,15 (m,2~I) 5.68-6.18 (m,lH); 6.85 (m,2H) Infra red (liquid film): 3600-3100, 29S0, 1640, 1585, 1435, 1315, 1215, 1190, 1115, 1030 cm (iv) 4-allyl-3,5-difluoroben~yl tetrahydropyranyl ether (mixture with 3,5-difluorobenzyl tetrahydropyranyl ether ) .
Infra red (liquid film): 2950~ 1640, 1595, 1585, 1435, 1200, 1115t 1070, 1030, 1000, 905 cm .

(v) 3,5-d.i:Eluorobenzyl alcohol - b.p. 200-202C.
Infra red (liquid film): 3600-3100, 2900, 1625, 1595 1460, 1320, 1115, 955, 850 cm EXAMPL~ 11 This Example illustrates ~he preparation o~ 4-allyl-2,6-difluorobenzyl alcohol.
(a) Allyl-3,5-difluorobenzene A solution of allyl bromide (2.5 g) in dry tetrahydro-furan (10 ml) was added dropwise with stirring to 3,5-difluorobromobenzene (4.0 g) with magnesium (0.5 g) in dry 2S tetrahydrofuran) in dry tetrahydrofuran (40 ml), ~hilst maintaining the temperature of the mixture at about 20~C.
~en the adclition was complete the mixture was allowed to warm to the ambient tempera-ture (ca. 25C).

118i7q~
~ 44 -After a period of 18 hours the mi.~ture was poured into water (100 ml) and the resultant mixture extrac-ted with diethyl e-ther, the extrac-t washec1 with water, clriecl over anhydrous magnesium sulpha-te and the ether removed by S distillation at atmospheric pressure. The residua] oil was purified by dis-tillation at atmospheric pressure to yield allyl-3,5-difluorobenzene (b.p. 154-155) as a colourless ', oil.
~.m.r. ( H(ppm)CDCl ): 3.40 (d,2H); 5.10 ~dd,2H);
6.~0 (m,lH);~6.70 (m,3~) .
(b) 4-Allyl~3,5-difluorobenzoic acid was obtained from the product of step (a) by using the procedure of step (b) of Example 2, as a white solid, m.p. 80-82C.
N.m.r. ( H(ppm)CDCl ): 3.40 (d,2H); 5.20 (dd,2H);
6000 (m,lH); 6.gO (d,2H), 10.90 ~s,lH) Infra red (l:iquid paraffin): 3300-2500, 1700, 1630, 1570, 1450, 1280, 1040, 930 cm (c) ~-Allyl-3,5-difluorobenzyl alcohol was obtained by the reduction of the product of step (b) by the use of the procedure of step (c) of Example 2.
~,m.r. ( H(ppm)C~Cl ): 3.40 (d,3H); 4.70 (s,2H);
5.20 (dd,2H); 6.00 (m,lH): 6.8 (d,2H) This Example illustra-tes the preparation of 3-methyl-2,4,5,6-tetrafluorobenzyl alcohol.
(a) 3-bromo-2,4,5,6-tetrafluorotoluene.
A solution of dimethyl sulphate (8.0 ml) in dry tetrahydrofuran (20 ml) was added slowly to a stirred solution o~ 3-bromotetrafluoroben~ene magnesium bromide Cobtained by the reaction of magnesium (1.6 g) with 1,3~
dibromo-tetra~luorobenzene (20 ml)] in dry te-trahydrofuran (150 ml) over 30 minutes at the ambient -temperature.

~5 -~en the addition was comple-te the mixture temperatur2 had risen -to 45C. The mixture was heated a-t the reflux temperat~re for 15 minutes ancl -then cooled to the ambien-t temperature (ca. 25~C)~ Dilute hydrochloric acid (30 ml of a 1~ solution) was added and -the mixture thereafter neutralised with satura-ted sodium bicarbona-te solution.
After diluting the mixtuxe with water (200 mL) it was extracted with ether and the extracts washed with water ancl dried over anhydrous magnesium sulphate. ~fter removal of the solven-t by evaporation under reduced pressure ~he residual oil was distilled to yield 3-bromo-2,4,5,6-tetra-fluorotoluene (9.0 g), b.p. 9G-98C/85 mm Hg.

(b) 3-methyl-2,4,5,6-tetrafluorobenzaldehyde n-Butyl lithi~m (12.9 ml of a 1.6M solution in hexane) was added dropwise to a solution of 3-bromo-2,4,5,6-tetra-fluorotoluene (5.0 g) in diethyl ether (40 ml) under an argon atmosphere whilst maintaining the mixture temperature within the range -60 to -70C. When the addition was complete the mixture was stirred for a period of 1.5 hours at -70C after which a solution of N-methylformanilide (2.8 g) in diethyl ether (15 ml) was added and the resultant mixture allowed to attain the ambient temperature (ca. 25C). Dilute hydrochloric acid (25 ml) of a 2~
solution) was added to the well-stirred mixture after ~hich the ethereal layer was separated, washed with water and dried over anhydrous magnesium sulphate. After removal of the solvent by evaporation under reduced pressure the re~sidual oil was distilled to yield 3-methyl-2,4,5,6-tetra-fluorobenzaldehyde (1.6 g) b.p. 78-80C/14 mm Hg.
Infra red (liquid film): 1710, 1640, 1490, 1140 cm 6~
- ~6 -I

(c) 3-Methyl--2,4,5,6-tetraflilorobenzaldehyde.
Sodium borohydride (0.3 g) was added in small portions to a solution of 3-methyl-2,4,5,6-tetrafluorobenzaldehyde (1.5 g) in methyl alcohol (15 ml) at the ambient tempera-ture, after WlliCh the mix-ture was hea-te~ at -the reflux temperature for 30 minutes. The methy]. alcohol was remo~ed by evaporation under reduc~d pre~sure and the residue partitioned between dilute hydrochloric acid (20 ml of a O.lN solution) and ether (20 ml). The ethereal phase was separated, washed with saturated sodium bicarbonate solution and with water and then dried over anhydrous magnesium sulphate. After evaporation of the ether under reduced pressure the product was distilled in a Kugelrohr apparatus to yield 3-methyl-2,4,5,6-tetrafluoroben~yl alcohcl (1.2 g) ~ approximate b.p. 100~/14 rnrn Hg.
N.m.r. ( H(ppm)CDCl ): 2.20 (s,3H); 3.20 (t,lH); ~.6 (m,2H) Infra red (liquid film): 3300, 1650, 14~0, 1120, 1110 cm ; This Example illustrates the preparation of 4-arnino-2,3,5,6-tetrafluorobenzyl alcohol.
Lithium aluminium hydride (0.2 g) was added in sm~11 portion to a stixred solution o 4-amino-2,3,5,6-tetra-fluorobenzoic acid (1.~1 g) in dry diethyl ether (20 ml) undex a nitrogen atmosphere and the mixture stirred at t~e ambient temperature (ca. 25C) for one hour and then heated at the reflux temperature for 3 hours. After cooling to the ambient temperature the mixture was kept for 18 hours before water was carefully added. The mixture was acidified with dilute h~drochloric acid (2~) and extracted with ether. The extxacts were washed with water dried over anhydrous magnesium sulphate and concentrated by evaporation of the ether. The resultant solid (a mixture of the desired product with the starting material) was washed with satura-ted sodiurn bicarhonate solution and the residual soli~ recrystallised ~rorn toluene to give ~-amino-t7~

2,3,5,6-tetraEluorohetlzyl alcohol (0.3 g) m.p. 92-94C.
N.m.r. ( H(ppm)CDCl /DMSO-d ): 4.60 (s,2H); 4.gO ~s,3H);
Infra red (liquid paraEfin)- 3350, 31~0, 1670, 1375, 1290, 1120, 1020, 900 cm .

This Example illustrates the preparation of 4-methoxy-2,6-difluorobenzyl alcohol.

(a) 2,4,6-Tri1uorobenzoic acid.
This was obtained from 1,3,5-trifluorobenzene by the procedure described in step (b) of Example 2. 2,4,6-Tri--fluorobenzoic acid was obtained as a off-white crystalline solid, mip. 131-133DC; when recrystallised from water.
.m.r. ~ H(~)CDCl ): 3.26 (t,2H). ~1 In~ra red (liquid paraffin): 3750-2500, 1710 cm I

(b) Methyl 2r4,6-trifluorobenzoate.
A mixture of 2,4,6-trifluorobenzoic acid (2.0 g) and thionyl chloride ~10 ml) was heated at the reflux temp-erature ~or 3 hours, after which the excess thionyl chloride was removed by distillation under reduced pressure, ~he final traces being removed by azeotropic distillation with toluene. The residual liquid ~infra red (liquid film):
1790 cm indicates 2,4,6-trifluorobenzoyl chloride, 1.5 g) was added to methanol (7.5 ml), and pyridine (2.0 ml) was added slowly to the stirred mixture. ~1hen the exother~ic reaction had subsided the mixture was kept at the ambient ~5 temperature (ca. 25C) for 18 hours, diluted with water, acidified with dilute hydrochloric acid and extracted with diethyl ether. The ethereal extracts were washed succes-sively with water, saturated sodium bicarbonate, and water ar,d dried over anhydrous magnesium sulphate. Af-ter removal o~ the ether by evapora-tion the residual liquid was subjec-ted - 'L8 -to distillation in a Kugelrohr apparatus, to give me-thyl 2,4,6-trifluorobenzoate ~1.1 g) having a boiling point of 105-110C/15 mg Mg.
N.m.r. ( H(~)CDCl ): 3.30 (t,2H) 6.10 (s,3H).
Infra red (liquid film): 1740 cm (c) Methyl 4-methoxy-2,6-difluorobenzoate.
A mixture of methyl 2,4,6-trifluorobenzoate (5.5 g) and a solution of sodium methoxide in methanol (obtained by dissolving sodium (0.73 g~ in' methanol ~10 ml) was refluxed for 7 hours, a~ter which the excess methanol was distilled off under reduced pressure. Water (50 ml) was added and the mixture extracted with diethyl ether. After drying over anhydrous magnesium sulphate the extracts were concen-trated by evaporation of the ether -to give a partly solidified residue. Trituration with cooled petroleum ether and filtration yielded white crystals of methyl 4-methoxy-2,6-difluorobenzoate (1.4 g) m.p. 82-84C.
N.m.r. ( H(~)CDCl ): 3.54 (d,2H; 6.10 ~s,3H); 6.19 (s,3H).
Infra red (liquid paraffin): 1735 cm - 20 (d) 4-Methoxy-2,6-di~luorobenzyl alcohol.
A solution of 'Red-A1' (1.5 g of a 70% solution of NaAlH
(OCEI CH OCH ) in toluene) was added slowly to a stirred solution of rnethyl 4-me-thoxy-2,6-difluorobenzoate rl.O g) in dry tetrahydrofuran (10 ml) at the ambient temperature. After the exotherrQic reaction had subsided the mixture was stirred for 30 minutes and ethyl acetate (10 ml) and water (200 ml) acidified with dilute hydrochloric acid (5 ml) were added. After extracting the mixture with ether (2 x 30 ml) the combined extrac-ts were dried over anhydrous magnesium sulphate and concentrated by evaporation of the ether. The residual oil was purified by flash chromatography on silica using an ethyl acetate/-petroleum ether eluent to give 4-methoxy-2,6-difluoro-ben~oyl alcohol (0.62 g)~

716~
_ ~9 M.m.r. ( H(~CDCl ): 3.59 (d,2H); 5.34 (s,2~); 6.20 (s,3H).
Infra red (liquid film): 3800 crn ~X~MPLE 15 This Example illustrates the pre~aration of 4-e-thyl-thio-2,3,5,6-tetra~luoroben~yl 3-(2-chloro-3,3,3-trifluoro-prop-1-en-1-yl)~2,2-dimethylcyclopropane carboxylate (compound no. 2, Table I) consisting o~ 50% w/w of the (~)-cis isomer and 50% w/w o~ the (~)-trans isomer (Product II).
. . _ A mixture of thionyl chloride (S.0 ml) and 3-(2-chloro-3,3,3-trifluoroprop-lYen-l-yl~-2,2-dimethylcyclo-propane carboxylic acid (50~ Ci9, 50% trans (w/w), 0.242 g) was h~ated at the reflux temperature for 5 hours, and then kept ~t the ambient temperature for 16 hours. After removing the excess thionyl chloride by evaporation under reduced pressure (the last traces being removed by azeo tropic disti]lation with toluene) the resultant acidchloride was added to a mixture of 4-ethylthiotetrafluoro-benzyl alcohol (0.24 g), dry pyridine (0.08 g) and dry toluene (10 ml), and the resultant mixture stirred at the ambient temperatures for 2 hours and then stood at the ambient temperature for a further 16 hours. After adding toluene (10 ml) the mixture was washed successively with dilute ~ydrochloric acid (2N, 20 ml), water and saturated sodium bicarbonate solution, dried over anhydrous magnesium sulphate and concentrated by evaporation of the solvent under reduced pressure yielding, as a residual oil, 4-ethylthio-2,3,5,6-tetrafluoroben~yl 3-(2-chloro-3,3,3-trifluoroprop-l-en-l-yl)-2,2-dimethylcyclopropane carboxylate, identified by n.m.r. and infra red spectrosclopy .
N.m.r. ( H(ppm~CDCl ) 1.16-1.38 (m,9H); 1.71-2.50 (m,2H), 2.97 (q,2H); 5.19 (2s,2H); 6.08, 6.82 (2d,1H).
In~ra red (l:iquid film): 2950, 1730, 16~0, 1470, 1270, 1130 1040, 910 cm EX~MPLE 16 By the use of the procedure set out in Example 15 above the following Products were prepared from the stated acids and alcohols, and identified by their n.m.r. and infxa red spectra.
Product I from 4-methyl 2,3,5,6-tetrafluoroberlzyl alcohol and 3-~2-chloro-3,3,3-trifluoroprop-1-en-1-yl)-2,2-dimethylcyclopropane carboxylic acid (50% cis 50% trans, w/w3.
~.m.r. ( H(ppm)CDCl ): 1.24~1.44 ~m,6H): 1.70-2.58 (m,2H) 2.28 ~t,3H); 5.20 5.28 (2s,2H); ~.12 6.90 (2d,lH).
Infra red (liquid film): 3060, 7735, 1655, 149Q, 1285, 1135 cm Product III from 4-methyl-2,3,5,6-te-tra~luorobenzyl alcohol and 3-(2,2-dichlorovinyl)-2,2-dime-thylcyclopropane carboxyl c acid (50% cls, 50% trans, w/~
N.m.r. ( H(ppm)CDCl ): 1.24~1.40 (m,6H); 1.56-2.36 (m,2H);
2.28 (t,3H); 5.20-5.28 (2s,2H); 5.58 6.22 {2d,lH).
- 20 Infra red (liquid film): 3060, 1735, 1655, 1~90, 1285, 1135 1060 cm Product IV from 4-ethanesulphonyl-2,3,5,6-tetrafluoro-benzyl alcohol and 3~(2-chloro-3,3,3-trifluoroprop-1-en-1-yl)-2,2-dimethylcyclopropane carboxylic acid (50% cls, 50% trans, w/w).
N.m.r.( H(ppm)CDCl ): 1.19-1.52 (m,9H); 1,68-2.~9 (m,2H);
3.31 (qO2H); 5.19 (2s,2H); 6.07, 6.77 (2d,1H).
Infra red (liquid film): 2950, 1730, 1650, 1480, 1340, 1280 1140, 1050 cm Product V from 4-metho~y-2,3,5,6-tetrafluorobenæyl alcohol and 3--(2-chloro-3,3,3-trifluoroprop-1-en-1-yl)-2,2-dimethylcyclopropane carboxylic aci~ (50~ cls, 50% trans, w/~ ) -~8~t7~

N.m.r. ( H(ppm)C~Cl ): 1.15-1.3~ (m,6H); 1.65-2.50 (m,2H);
4.00 (d,3H); 5.10 (m,2EI) 6.04, 6.78 (2cl,lH).
Infra red (liquid film): 29S0, lt30, 1650, 1500, l420, 1300 S 1280, 1200, 1140, 1050, 950 cm Product VI from 2-methyl-3,4,5,6-tetrafluorobenzyl alcohol and 3-(2-chloro-3,3,3-trifluoromethylprop-1-en-l-yl)-2,2 dirnethylcyclopropane carboxylic acid ~50~ cls, 50% trans, w/w).
N.m.r. ( H~ppm)CDCl ): 1.24-1.40 (m,6H); 1.72-2.52 (m,2H) 2.30 (t,3H); 5.10 5.20 (2s,2H); 6.10, 6.82 (2d,1H).
Infra red (liquid film): 3060, 1735, 1655, 1515, 1490, 1280 Product VII rrom 4-ethoxy-2,3,5,6-tetrafluoroberlzyl alcohol and 3-(2-chloro-3,3,3-trifluoroprop-1-en-1-yl)-2,2-dimethylcyclopropane carboxylic acid ~50% cis, 50~ trans, w/w ) .
N.m.r. ( H(ppm)CDCl ): 1.18-1.51 (m,9H); 1.69-2.50 (m,2H) 4.27 (q,2H), 5.13 (2s,2~); 6.06, 6.79 (2d,1H).
Infra red (liquid film): 2950, 1730, 1650, 1500, 1395, 1300 12t30, 1200, 1140, 1050, 950 cm Produc-t VIII from 4-ethoxy-2,3,5,6-tetrafluorobenzyl alcohol and 3-(2,2-dichlorovinyl)-2,2~dimethylcyclopropane carboxylic acid (50% cis, 50% trans, w/w).
~.m.r. ( H(ppm)CDCl ): 1.15-1.52 (m,9H); 1.53-2.32 (m,2H) 4.29 (q,2H); 5.1~ (2~,2H); 5.54, 6.17 (2d,1H) Infra red (liquid film): 2950, 173G, 1650, 1500, 1395, 1220 1160, 1130, 1045, 1020, 940 cm Product IX from 4-methyl-2,3,5,6-tetrafluorobenzyl alcohol and 3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane carboxyl c acid ~100% c:Ls isorner).
.m.r. ( H(ppm)CDCl ): 1.24 (s,6H), 1.72-2.12 (m,2H):
2.28 (t,3H); 5.12 (s,2H~; 6.16 (d,lH) Infra red (liquid film): 3~60, 1735, 1655, 1490~ 1285, 1135 cm ~8~

Product X from 4-methyl 2,3,5,6-tetrafluorobenzyl alcohol and 3-(2-chloro-3,3,3-trifluoroprop-1-en-1-yl)-2,2-dimethylcyclopropan~ carboxylic acid (100% cis i~omer).
N.m.r. ( H(ppm)CDCl ): 1.28 (s,6H); 1.92-2.44 (m,5H);
5.25 (s,2H); 6.92 (cl,lH).
In~ra red (liquid film): 3080, 1735, 1655, 1495, 1135 cm Product XI from 4-ethyl-2,3,5,6-tetrafluorobenzyl alcohol and 3-(2-chloro-3,3,3-trifluoroprop~l-en-1-yl)-2,2-dimethylcyclopropane carboxylic acid (100% cis isomer).
N.m.r. ( H(ppm)CDCl ): 1.14 (t,3H); 1.24 (s,6H);
1.92-2.28 (rn,2H); 2.72 (q,2H);
5.14 (s,2H); 6.88 (d,lH).
Infra red (liquid film): 3080, 1735, 1655, 1495, 1135 cm Product XII from 4-methoxy-2,3,5,6-te-trafluorobenzyl alcohol and 3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane carboxylic acid (100% cls isomer).
N.m.r. ( H(ppm)CDCl ): 1.15-1.38 (m,6H)~ 1.55-2.33 (m,2H);
4.10 (d,3H); 5.19 (m,2H); 2.59, 6.22 (dd,lH) Infra red ~liquid film): 2950, 1730, 1650, 1500, 1160, 1140 cm Product XIII from 4-n-butyl-2,3,5,6-tetrafluoro~enzyl alcohol and 3-(2-chloro-3,3,3-trifluoroprop-1-en-1-yl)-2,2-dimethylcyclopropane carboxylic acid (100% cis isomer).
N.m.r. ( H(ppm)CDCl ): 0.98 (m,3H); 1.30 ~s,6EI);
1.20-1.76 (m,4H); 1.92-2.38 (m,2H);
2.65-2.91 (m,2H~; 5.20 (t,2H); 6.90 (d,lH) Infra red (liquid film): 2950, 1730, 1650, 1495, 1295, 1270 1200, 1140, 1050, 1000, 950 cm Product XIV ~rom 4-allyloxy-2,3,5,6-tetrafluorobenzyl alcohol and 3-(2-chloro-3,3,3-trifluoroprop-1-en-1-yl)-2,2-dimethylcyclopropane carboxylic acid ~100~ cis iSQm~r).
N.m.r. ( H(ppm)CDCl ): 1.26 (s,6H); 1.89-2.34 (m,2H);
4.72 (d,2H); 5.12-5.50 (m,4~I);
. 5.80 (m,lH); 6.88 (d,lH).
In~ra red (liquid ~ilm): 2950, 1730, 1650, 1495, 1295, 1270 1200, 1140, 1050, 1000l 950 cm ~:~8~L'768 - 53 - 1, '.

Product XV frorn ~-metho~y-2,3,5,6-tetrafluorobenzyl alcohol and 3-(2-chloro-3,3,3~trifluoropro~ en-1-yl)-2,2 dimethylcyclopropane carboxylic acid (100~ cl~ isomer).
N.m.r. ( H(ppm)CDCl ): 1.]4 (s,6H); 1.85-2,25 (m,2H);
4.02 (d,3H); 5.10 (s,2H); 6.78 (d,lH) Infra red (liquid film): 2950, 1730, 1650, 1500, 1300, 1275 1200, 1140, 1050, 950 cm Product XVI from 3-methyl-2,4,5,6-tetrafluorob~nzyl alcohol and 3-(2-chloro~3,3,3-trifluoroprop-1-en-1-yl)-2,2-dimethylcyclopropane carboxylic acid (100% cis isomer).
N.m~r. ( H~ppm)CDCl ): 1.3 (s,6H); 2.0 (m,5H);
5.1 (m,2H); 6.8 (d,lH);
Infra red ~liquid film): 1730, 1650, 1500, 1300, 1280, ll~a cm Product XVII from 3-methyl-2,4,5,6-tetrafluorobenzyl alcohol and 3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane carboxyl c acid (50% cis, 50~ trans, w/w).
~-m-r- ( H(ppm)CDC13): 1.2 (q,6H), 1.8 (m,2H); 2.2 ~m,3H) 5.1 (m,2H); 5.5, 6~2 (dd,lH).
Infra red (liquid film): 1830, 1650, 1500, 1360, 1340, 1320 cm Product XVIII from 4-allyl-2,3,5,6-tetrafluorobenzyl alcohol and 3-(2-chloro-3,3,3-trifluoroprop-1-en-1-yl)-2,2-dimethylcyclopropane carboxylic acid (100% cls isomer~.
N.m.r. ( H(ppm)CDCl ): 1.30 (s,6H); 1.90-2.32 (m,2H);
3.50 (m,2H); 4.95-5.30 (m,4H);
5.70-6.10 (m,lH); 6.90 (d,lH).
Infra red (liquid film): 2950, 1730, 1650, 1495, 1300, 1280, 1200, 1140, 950 cm Product XIX from 4--n-propyl-2,3,5,6-tetrafluorobenzyl alcohol and 3-(2-chloro-3,3,3-trifluoroprop-1-en-1-yl)-2,2-dimethylcyclopropane carboxylic acid (100~ Ci5 isomer).
N.m.r. ( H(ppm)CDCl ): 0.94 (t,3H); 1.24 (s,6H):
1.60 (q,2H); 1.84-2.26 (m,2H);
2.66 (t,2H); 5.08 ~s,2H); 6.72 (d,lH).
In~ra red ~liquid film): 3075, 173S, 1655, 1~90, 1135 cm ~ ` ~
~ 5~ -Product XX from 4-allyl-2,3,5,6-tetrafluorohen~yl alcohol and 3-(2,2-dic~lorovinyl)-2,2-dimethylcyclopropane carboxylic acid (50~ cis, 50~ trans, w/w).
N.m.r. (lH(ppm)C~C13) 1.20 (m,6H); l.S3-2.30 (m,2H);
3.41 (m,2H), 4.88-5.23 ~m,4H);
5.59-6.00 (m,lH); 5.52, 6.14 (dd,lH~.
Infra red tliquid film): 3960, 1730, 1640, 1495, 1280, 920, 880 cm~l.
Product XXI from 4-(3-methylbut 2-en 1-yl)-2,3,5,6-tetrafluorobenæyl alcohol and 3-(2-chloro-3,3,3-trifluoro-prop-l-en-l-yl)-2,2-dimethylcyclopropane carboxylic acid (100% cis isomer).
N.m.r. (lH(ppm)CDC13): 1.27 (s,6H); 1.70 (d,6H);
1~83-2.29 (m,2H); 3.39 (m,2H);
4.90-5.25 (m,3H); 6.~5 (d,lH).
Infra red (liquid film): 2950, 1730, 1~50, 1495, 1300, 1280, 1200, 1180, 1140, 1050, ! 960, 860 cm~l.
Produc-t ~II from 4-(but-2-en-1-yl)-2,3,5,6-tetrafluoro-benzyl alcohol and 3-(2-chloro-3,3,3-trifluoroprop-1-en-1-yl)-2,2-dime~hylcyclopropane carboxylic acid (100% _s isomer).
N.m.r. (lH(pprn)CDC13): 1.28 (s,6H); 1.58-1.82 (m,3H);
1.90-2.30 (m,2H); 3.35-3.60 (m,2H);
5.20-5.75 (m,4H); 6.g2 ~d,lH).
Inra red (liquid film): 2980, 1730, 1650, 1490, 1300, 1275, 1200, 1170, 1130, 950 cm~l.
Product XXIII from 4-allyl-2,6-difluorobenzyl alcohol and 3-(2-chloro-3,3,3-trifluoroprop~l-en-1-yl)-2,2-dimethyl-cyclopropane carbo~ylic acid (100% cis isomer).
N.m.r. (lH~ppm)CDC13): 103 (d,6H); 1.9 (d,lH); 2.15 (t,lH~
3.35 (d,2H); 5.1 ~m,2H); 5.15 (s,2H) 5.8 (m,lH); 6.75 ~d,2H); 6.95 (d,lH) Infra red (liquid film): 1730, 16~0, 1590, 1440 cm~l 7~

!
Product XXIV frorn 4~allyl-3,5-difluorobenzyl alcohol and 3-(2-chloro-3,3,3-trifluoroprop-1-en-1-yl)-2,2-dlmethyl-cyclopro~ane carboxylic acld (100% cis isomer~
N.m.r. ( H(ppm)CDCl ): 1.31 ts,6H); 1.98-2.20 (m,2H), 3.43 (m,2H); 4.95-5.25 (m,4H~;
5.78-6.20 (m,lH); 6.80-7.15 (m,3H).
In~ra red (liquid film): 2960, 2920, 1730, 16aO, 1590, 1440 1410, 1360, 1300, 1270, 1200, 1170 1130, 1080, 960, 760 cm Product XXV ~rom 4-benzyl~2,3,5,6-tetrafluorobenzyl alcohol and 3-(2-chloro-3,3,3-trifluoroprop-1-en-1-yl)-2,2-dimethylcyclopropane carboxylic acid (100% ClS isomer).
N.m.r. t H(ppm)CDCl ): 1.28 (s,6H); 1.88-2.30 (m,2H~;
4.08 (s,2H); 5.20 ~s,2H);
6.90 (d,lH); 7.28 ~s,5H).
Infra red (liquid ~ilm): 3080, 1735, 1655, 1495, 1165 cm Product XXVI from 4-methoxy-2,3,5,6-tetrafluorobenzyl alcohol and 3-(2,3,3,3-tetrafluoroprop-1-en-1-yl)-2,2-dimethylcyclopropane carboxylic acid ¦100~ cls isomer).
N.m.r. ( H(~)CDCl ): 3.92 (dd,lH); 4.80 (s,2~); 5.90 (m,3H);
7.90 (q,lH), 8.10 (d,lH); 8.75 (s,6H).
Infra red (liquid film): 1735 cm Product XXVII from 4-methoxy-2,3,5,6-tetrafluorobenzyl alcohol and 3-(2,3,3,3-tetrafluoroprop-1-en-1-yl)-2,2-dimethylcyclopropane car~oxylic acid (100% trans isomer~.
N.m.r. ( H(l)CDCl ): 4.72 (dd,lH); 4.80 (s,2H); 5.90 (m,3H);
7.63 (q,lH); 8.30 (d,lH); 8.70 ~s,3H);
8-82 (s,3H). 1 Infra red (liquid film): 1735 cm Product XXVIII from 4-methyl-2,3,5,6-tetrafluoroben~yl alcohol and 3-(2,3,3,3-tetrafluoroprop-l~en-1-yl)-2,2-dimethylcyc]opropane carboxylate (100% cis isomer).
.m.r. ( H(~)CDCl ): 3.92 (dd,lH); 4.78 (s,2H~; 7.71 (m,3H) 3.78 (q,lH); 8.10 (d,lH): 8.73 (s,6H).
3S Infra red (liquid film): 1735 cm 7~
5 ~; ~

Prod~c-t XXIX from 4-ltlethyl-2,3,5,6 tetrafluorobenæyl alcoho:L and 3-(2,3,3,3-tetrafluoroprop-l~en-1-yl)-2,~- ' dimethylcyclopropane carboxylate (100% trans isomer). I
N.m.r~ ( H(l)CDCl ): 4.72 (dd,lH)i 4.75 (s,2H); 7.70 (m,lH) 7.72 (m,3H); 8.30 (d,lH); 8.70 (s,3H);
8.80 (s,3H). 5 Illfra red (liquic1 film): 1735 cm Product XXX from 4-allyl-2,3,5,6-te~rafluorobenzyl alcohol and chry ~nthemic acid (5Q~ cl~, 50~ trans, w/w).
10 N~m.r. ( H(ppm~CDC~ 2 (m,6H); 1.6 (m,6H); 1.4-2.1 (m,2EI) 3.5 (d,2H); 5~0~5O3 (m,3H); 5.2 (s,2H);
5~9 ~m,lH) Infra red (liquid fil~): 1740 cm .
Procluct XX~I from 4-metho~y-2,6-difluoroben~yl alcohol 15 and 3-(2-chloro-3,3,3-trifluoroprop-1-en-l~yl)-2,2-dimethylcyclopropane carboxylic acid (100% cis isomer).
N.m.r. ( H(~)CD~ 3.07 (d,lH); 3.52 (d,2H), 4.86 (s,2H) 6.20 ~s,3H); 7.60-8.10 ~m,2H);
8.70 (s,6H).
Infra red (liquid film): 1730 cm Product ~XXII from 4-allyl~2,3,5,6-tetrafluoroben~yl alcohol and 3-(2,3,3,3-tetrafluoroprop-1-en-1-yl)-~,2-dimethylcyclopropane carhoxylic acid tlO0% c~s isomer).
N.m.r. ( H~)CDC1 ): 3.95 ~dd,lH); 4.10 ~m,lH); 4.70-3 5.02 (m,4H), 8.72 (s,6H~.
Infra red (liquid film): 1735 cm Product XXXIII from 4-allyl-2,3,5,6-tetrafluoroben7yl alco'nol and 3-(2,3,3,3-tetrafluoroprop-1-en-1-yl)-2,2-dimethylcyclopropane carboxylic acid (100% trans isomer).
N.m.r. ( H(~)CDCl ): 4.10 (m,lH); 4.5-S.0 ~m,5H);
6.50 (d,2H); 7.74 (m,lH); 8.30 (d,lH);
8.78 (s,3H), 8.80 (s,3H~O
Infra red (liquid film): 1735 cm Product XXXIV from 4 allyl-2,3,5,6~tetra~1uorobenzyl alcohol and 3-(2,2-dibromovinyl)-2,2-dimethylcyclopropane carboxyl c acid (100~ cis isomer).
~.m.r. ( H(~)CDCl ): 3~24 (d,l-~); 4.10 (m,lH); 4 70 5.0 (m,4H); 6.50 (d,2H), 7.80-8.22 (m,2H); 8.72 (s,6EI).
Infra red ~liquid film): 1735 cm Product XXXV from 4-amino-2,3,5,6-tetrafluorobenzyl alcohol and 3-(2,3,3,3-te~ra~luoroprop-1-en-1-yl)-2,2-dimethylcyclopropane carboxylic acid (50~ cis, 50~ trans w/w) .
.m.r. ( H(ppm)CDCl ): 1.27 (m,6H); 1.63-2.44 (m,2H);
4.16 (m,2~); 5.20 (s,2H); 5.12, 5.45 5.92, 6.27 (4d,1H).
15 Infra red (liquid film): 3500, 3380, 3200, 2980, 1730, 1670 1510, 1365, 1300~ 120Q, 1175,

11$0 cm EX~MPLE 17 ~ his Example illustrates the preparation of 4-aceto-amido-2,3,5,6~tetra~1uorobenzyl 3-(2,3,3,3-tetra~luoroprop-1-en-1-yl)~2,2-dimethylcyclopropane carboxylate consisting of 50~ of the (+)-cis isomer and 50% of the (')-trans isomer (Product XXXVI).

Ac~tyl chloride (60 mg~ was added to a stirred solution of 4-amino-2,3,5,~-tetrafluorobenzyl 3-(2,3,3,3-tetrafluoroprop-1-en-1-yl)-2,2-dimethylcyclopropane carboxylate (50% c , 50~ trans w/w (Product XXXV 120 mg) in dry toluene (4.0 ml), after which dry pyridine (60 mg) was added to the mixture, the additions taking place at the ambient temperature (ca. 25C). After stirring the mixture for two hours it was diluted with fur-ther toluene and washed in succession with water and saturated sodium bicarbonate solution, and finally dried o~er anhydrous magnesium sulphate.

After removal of the toluene by evaporation under reduced pressure the residual oil was purifiecl by thick layer preparative chromato~raphy tsilica ~el (2 mm thick);
chloroform eluent) to yield 4-acetamido-2,3,5,6-tetr~-~luorobenzyl 3~(2,3,3,3-tetrafluoroprop-1-en-1-yl) 2,2-dime-thylcyclopropane carboxylate (50% cls, 50~ trans, w/w) as a viscous colourless oil.
N~m.r. ( H~ppm)CDCl ): 1.23 (m,6H); 1.63-2.44 (m,2H);
2,20 (s,3H); 5.20 (s,2H); 5.12, 5.43 5.86, 6.18 (4d,1H); 7.90 (s,lH).
Infra red (liquid film): 3250, 2980, 1730, 1690, 1660, 1500 1480, 1370, 1200, 1170, 1155, 1150 cm .i NDB/SPEC656667/bgg `i

Claims

The embodiments of the invention in which an exclusive property or privilege is claimed is defined as follows:

1. A compound of formula wherein X is oxygen, sulphur, sulphonyl, or a group NR4 wherein R4 represents hydrogen, lower alkyl or lower carboxylic acryl; R3 represents lower alkyl, lower alkenyl or benzyl, and additionally R3 may be hydrogen when X is a group NR4; m has the value zero or one, and n has a value of from one to four; provided that (X)mR3 is not 4-methoxy when n is four.