FIELD OF THE INVENTION
[0001] The present invention relates to the field of insecticides derived from chrysanthemic
acid.
STATE OF THE ART
[0002] 2,2-dimethyl-3-(2-methylpropenyl)cyclopropanecarboxylic acid (chrysanthemic acid)
is a starting material for the synthesis of a number of pyrethroid insecticides, widely
used in agriculture and the domestic field for controlling ants, spiders, mosquitoes,
flies and other unwanted insects. The esters of said acid and their derivatives in
position 3 of the cyclopropane ring are of particular interest. Included among them
are the 3-dichlorovinyl derivative esterified with 2,3,5,6 tetrafluorobenzyl alcohol
(transfluthrin), and (2,3,5,6-tetrafluoro-4-methoxymethyl)benzyl-2,2-dimethyl-3-prop-1-enylcyclopropanecarboxylate
(metofluthrin); metofluthrin and other similar compounds are described in
EP-A-939 073. Other 3-vinyl-2,2,dimethylcyclopropanecarboxylic derivatives esterified with furyl
or thienyl alcohols are known from
DE-A-2 113 124. In
EP-A-31 041 phenoxybenzyl esters of cyclopropanecarboxylic acid, containing in position 3 a mono/poly-halogenated
diene substituent are described. Pestic.Sci.,1976,7,p.499-502 describes 3-alkadienylcyclopropanecarboxylic
derivatives, in which the carboxyl is esterified with 5-benzyl-3-furanmethanol. Similar
derivatives are known from
DE-A-2 231 436.
[0003] Despite the introduction of the different aforementioned insecticides, the need was
however felt for new higher strength insecticidal compounds, with a wide spectrum
of action and well tolerated by man and animals.
DESCRIPTION OF THE FIGURES
[0004]
Figure 1: Structure of the compounds of examples 1-3 of the invention with stereochemical indicators;
Figure 2: Structure of the compounds of examples 4 and 8 of the invention and of comparative
compound of example 7 with stereochemical indicators.
SUMMARY
[0005] It has now been found that compounds of structural formula (I)

wherein n is chosen from 1 and 2 and R is chosen from -H, -CH
3, C
2H
5, -OCH
3, - OC
2H
5, and -CH
2-OCH
3 exhibit an unexpectedly high insecticidal activity.
DETAILED DESCRIPTION
[0006] The preferred compounds according to the invention are those having formula (I) wherein
R is H or -CH
2-OCH
3. Particularly preferred are the following compounds:
2,3,5,6-tetrafluorobenzyl-(1RS,3RS)-3-((E/Z)-Buta-1,3-dienyl)-2,2-dimethylcyclopropane-1-carboxylate;
2,3,5,6-tetrafluorobenzyl-(1R,3R)-3-((E)-Buta-1,3-dienyl)-2,2-dimethylcyclopropane-1-carboxylate;
2,3,5,6-tetrafluorobenzyl-(1R,3R)-3-((E/Z)-Buta-1,3-dienyl)-2,2-dimethylcyclopropane-1-carboxylate;
2,3,5,6-tetrafluorobenzyl-(1R,3R)-3-(Hexa-1,3(E)-5(E/Z)-1,3,5-trienyl)-2,2-dimethylcyclopropane-1-carboxylate;
2,3,5,6-tetrafluoro-4-methoxymethyl benzyl (1 R,3R)-3-((E/Z)-Buta-1,3-dienyl)-2,2-dimethylcyclopropane-1-carboxylate.
[0007] The compounds of formula (I), compared to other commonly used 2,3,5,6 tetrafluorobenzyl
esters of 2,2-dimethylcyclopropanecarboxylic acid derivatives, such as transfluthrin
and metofluthrin, are found to be surprisingly more active. The spectrum of action
is wide-ranging and includes common flying and crawling insects; preferred among the
flying insects is the mosquito; preferred among the crawling insects are arthropods,
for example the Blattellidae.
[0008] The invention comprises a process for the synthesis of the aforesaid compounds of
formula (I). They can be produced by esterification of an acid of formula (II) with
an alcohol of formula (III) where, in said formulas, n and R have the aforesaid meanings.

[0009] The esterification preferably takes place after activation of the COOH group of compound
(II). Activation methods are known from the chemical literature, such as conversion
of carboxyl to acyl halide; this latter is easily obtained for example by reacting
compound (II) with an acyl chloride such as tosyl chloride, in the presence of a suitable
amine such as N-methylimidazole, in acetonitrile as the solvent. The activated carboxyl,
in the presence of alkaline catalysis, reacts at high yield with the alcohol (III)
to provide the desired compound (I).
[0010] The precursor compounds of formula (III) are commercially available or can be produced
by methods described in the literature.
[0011] The precursor compound of formula (IIa), (i.e. those of formula (II) with n=1) are
obtainable on the basis of the following reaction scheme, where R' is a C
1-C
3 alkyl, preferably ethyl.

[0013] Step 3 is a hydrolysis with alkaline catalysis carried out under standard conditions.
The compounds of formula (IIb) (i.e. those of formula (II) in which n=2) are obtainable
on the basis of the following reaction scheme, where R' is a C1-C3 alkyl, preferably
ethyl.

[0014] This scheme differs from the preceding in that at point 2.b two addition reactions
are carried out: the first with a formylmethyltriphenylphosphonium halide (this reaction
typically takes place in an aromatic solvent such as benzene, in the presence of triethylamine,
at ambient temperature); the product obtained is then reacted with an allyltriphenylphosphonium
halide, under the aforegiven conditions for this reagent.
[0016] A particularly effective synthesis path for obtaining the compounds of formula (I)
where n=2, with high yield and purity, comprises the formation of an aldehyde ester
of formula (VII) where R has the meanings defined in formula (I).

[0017] By converting the -CHO group of compound (VII) into an allyl group, the desired compounds
of formula (I), with n=2, are obtained. The conversion into an allyl group is obtained
by treating compound (VII) with an allyltriphenylphosphonium halide, under the aforestated
conditions for this reagent.
[0018] The intermediates of formula (VII) are new, and as such constitute a further aspect
of the invention. They can be themselves synthesized by treating a compound of formula
(VIII) with a formylmethyltriphenylphosphonium halide, where R has the previously
defined meanings.

[0019] The reaction of compound (VIII) with the formylmethyltriphenylphosphonium halide
takes place under the aforegiven conditions for this reagent.
[0020] The compound (VIII) can itself be obtained by ozonolysis starting from the corresponding
ester of chrysanthemic acid having formula (IX).

[0022] The compounds of formula (I) of the invention are chiral, containing centres of asymmetry,
and are optically active: they can be present in eight stereoisomeric forms for n=1
and in sixteen stereoisomeric forms for n=2 characterized by different geometric and
optical isomery, and in their respective mixtures. The present invention therefore
extends to the individual optical and geometric isomers having formula (I), and to
mixtures thereof in any proportion.
[0023] The aforesaid optical and geometric isomers are obtained by applying the aforedescribed
process on derivatives of formula (IV), (V), (VI a/b), (II a/b) having a specific
optical and geometric configuration; said configuration is reproduced in the final
compound (I). Specifically, to obtain the 1R,3R stereoisomer of compound (I), the
corresponding 1 R,3R stereoisomers of the intermediates (IV), (V), (VI a/b), (II a/b)
are used. In order to obtain the 1 S,3S stereoisomer of compound (I), the corresponding
1S,3S stereoisomers of the intermediates (IV), (V), (VI a/b), (II a/b) are used.
[0024] By working with enantiomeric mixtures (racemic or enantiomerically enriched) of the
aforesaid precursor intermediates, the compounds of formula (I) are obtained in the
corresponding mixtures.
[0025] Similarly, compounds of formula (I) with diastereoisomeric configuration (Z) or (E)
are obtained starting from the intermediates (VI) and (II) having the same configuration,
which are themselves obtainable from the aldehyde of formula (V) in a suitable configuration
by Horner Emmons reaction with diethylallyl phosphonate.
[0026] The E/Z diastereoisomeric mixtures of the compounds of formula (I) are obtained starting
from the corresponding diastereoisomeric mixtures of the aforestated precursor intermediates.
[0027] A further aspect of the present application is an insecticidal composition comprising
one or more compounds of formula (I) as previously defined. Optionally, to complement
and/or increase the spectrum of action, said compositions can contain, in addition
to the compounds of formula (I), further insecticidal compounds chosen from those
commonly available and more indicated for the chosen treatment. Synergistic compounds,
i.e. not themselves insecticides but which contribute to increasing the activity of
the compounds of formula (I), can be included in the compositions; synergistic compounds
such as, e.g. ,piperonyl butoxide and 1-(3,4-dimethoxyphenyl)ethyl 2-butyn-1-yl ether,
known as Verbutin, are well known in the insecticide field.
[0028] The insecticidal composition can be produced in solid form (e.g. powders, granules)
or liquid form (solutions, suspensions, emulsions, microemulsions) using techniques
known in the art. The formulation can also be encapsulated to achieve modulated release
over time. In the present insecticidal compositions, the compound of formula (I) is
contained in a weight/weight percentage comprised between 0.001% and 95%, preferably
between 0.001% and 50%, and more preferably between 0.001% and 5%. If two or more
compounds of formula (I) are used, the aforesaid weight percentages would refer to
the overall sum of the compounds of formula (I) present in the composition. In addition
to the aforementioned active principles, adjuvants chosen from those commonly used
in insecticidal compositions can be present. These include emulsifiers, UV stabilizers,
antioxidants and other additives that are non-specific for insecticidal activity but
useful for the specific application. Examples of emulsifiers are dodecylbenzenesulphonate,
lignosulphonates, phospholipids, polyethylene glycols. Examples of UV stabilizers
are 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxy-benzophenone, 4-hydroxy-2,2,6,6-tetramethylpiperidine
sebacate. An example of an antioxidant is 2,6-di-tert-butyl-1-hydroxy-toluene.
[0029] A further aspect of the present application is a process for preparing the aforesaid
insecticidal compositions comprising mixing one or more compounds of formula (I) as
previously defined with one or more excipients useful for insecticidal formulations,
and optionally other active principles with insecticidal activity, and synergistic
compounds.
[0030] The invention also includes a method for eliminating insects, characterized by bringing
into contact a substrate containing said insects with one or more of the aforedefined
suitably formulated compounds of formula (I); the substrate can be an enclosed environment
(house, school, office and other public premises, etc) or an open environment (gardens,
parks, surfaces of agricultural use, etc); the substrate can be an article, e.g. fabrics,
mattresses, carpets containing the insects to be eliminated; the substrate can be
the air present in one of said environments or one of the surfaces that comprise said
environments; the substrate can also be the surface of an animal contaminated by insects;
in this latter case the compounds of formula (I) can be applied directly onto the
animal after suitably formulating with suitable excipients for veterinary use. The
compound of formula (I) is dispensed at the times and in amounts determined on the
basis of the volume of the environment to be treated, and the degree of its infestation.
The compounds of formula (I) present a low toxicity to man and animals and can therefore
be used with a wide safety margin.
[0031] The following examples serve to illustrate the invention.
EXAMPLE 1: 2,3,5,6-tetrafluorobenzyl-(1RS,3RS)-3-((E/Z)-Buta-1,3-dienyl)-2,2-dimethylcyclopropane-1-carboxylate
a. Synthesis of (1RS,3RS)-3-((E/Z)-Buta-1,3-dienyl)-2,2-dimethylcyclopropane-7-carboxylic acid
[0032] (1RS,3RS)-3-((E/Z)-Buta-1,3-dienyl)-2,2-dimethylcyclopropane-1-carboxylic acid is
prepared from the corresponding ethyl (1 RS,3RS)-3-carboxyaldehyde-2,2-dimethylcyclopropane-1-carboxylate,
obtained by ozonolysis of racemic 80:20 trans/cis chrysanthemic acid ethyl ester;
the ozonolysis product is then subjected to a Wittig reaction with allyl triphenylphosphonium
bromide as described in
J.Chem. Soc. (C),1076, (1970), followed by alkaline hydrolysis of the ester, after purification
on silica gel column with 100/1 (v/v) petroleum ether/ethyl ether as eluent. The resulting
acid, obtained by acidification of the corresponding salt, is used in the crude form
for the subsequent reaction.
b. Synthesis of 2,3,5,6-tetrafluorobenzyl-(1RS,3RS)-3-((E/Z)-Buta-1,3-dienyl)-2,2-dimethylcyclopropane-7-carboxylate
[0033] 3.4 ml (43 mmol) of N-methylimidazole, CH
3CN (43 ml) and finally 2.38 g (14.3 mmol) of (1 RS,3RS)-3-((E/Z)-Buta-1,3-dienyl)-2,2-dimethylcyclopropane-1-carboxylic
acid are introduced into a flask under nitrogen atmosphere. The mixture is cooled
to 0ºC and a solution of 3.26 g (17.2 mmol) of tosyl chloride dissolved in 19 ml of
CH
3CN is added. At the end of the addition, the mixture is left at ambient temperature
for 45 minutes, then cooled again to 0ºC and 2.6 ml (14.3 mmol) of 2,3,5,6-tetrafluorobenzyl
alcohol dissolved in 16 ml of CH
3CN are added. The mixture is agitated at ambient temperature for 4 hours, diluted
with H
2O and transferred into a separating funnel. The reaction mixture is extracted 3 times
with ethyl ether and the organic phases washed with water and with a saturated NaCl
solution. The ether phase is separated, dried over Na
2SO
4 and filtered. Following evaporation at 21 mbar/30ºC, the crude reaction product is
taken up in 100/1 (v/v) petroleum ether/ethyl ether and purified on a silica gel chromatography
column using the same eluent. By evaporation of the solvent, 4.61 g of an oily product
with a purity equal to 97.0% is obtained.
IR (CHCl
3, cm
-1) 3200, 3086, 2925, 1725, 1178.
1H NMR (CDCl
3) δ 7.13-7.04 (m, 1 H, CHAr), 6.75-6.65 (m, 1 H, CH=(Z)), 6.33-6.08 (m,
4 vinyl CH (E)+(Z)), 5.45-5.39 (m, 1 H, vinyl CH (
Z)), 5.26-5.10+4.99-4.97 (m, 8 H, 2 vinyl-CH
2 + 2CH
2O
(E)+(Z)), 2.36-2.32 (m, 1H, CH-cyclopropane (
Z)), 2.10-2.07. (m, 1H, CH-cyclopropane (E)), 1.58 (d, 1H,
J = 7.5 Hz, CH-cyclopropane (
Z)), 1.54 (d, 1H,
J=5.2 Hz, CH-cyclopropane (
E)), 1.28 (s, 3 H, Me, (
Z)), 1.26 (s, 3 H, Me, (
E)), 1.1 (s, 6 H, 2Me,
(Z)+(E)).
13C NMR (CDCl
3) δ 171.16, 171.07, 147.12-146.84 (m, aromatic C-F), 146.56-146.37 (m, aromatic C-F),
144.65-144.37 (m, aromatic C-F), 144.07-143.84 (m, aromatic C-F), 136.44, 133.15,
132.23, 131.77, 130.95, 128.32, 118.16, 115.75, 115.37 (t, J=18Hz, aromatic-C), 106.61
(t, J=22Hz, aromatic-CH), 53.59, 36.62, 35.04, 34.03, 32.43, 29.81, 29.68, 22.0, 21.91,
20.26, 20.23
EXAMPLE 2: 2,3,5,6-tetrafluorobenzyl-(1R,3R)-3-((E)-Buta-1,3-dienyl)-2,2-dimethylcyclopropane-1-carboxylate
a. Synthesis of (1R,3R)-3-((E)-Buta-1,3-dienyl)-2,2-dimethylcyclopropane-1-carboxylic
acid
[0034] (1R,3R)-3-((E)-Buta-1,3-dienyl)-2,2-dimethylcyclopropane-1-carboxylic acid is prepared
from the corresponding ethyl (1R,3R)-3-carboxyaldehyde-2,2-dimethylcyclopropane-1-carboxylate,
obtained by ozonolysis of (1R,3R) chrysanthemic acid ethyl ester by reaction with
diethylallyl phosphonate according to the following reaction scheme:
[0035] 5.02 ml (28.8 mmol) of diethylallyl phosphonate are dissolved in 43 ml of anhydrous
tetrahydrofuran in a flask under nitrogen atmosphere. The mixture is cooled to -78ºC
and 18 ml of a solution of 1.6 M butyllithium in n-hexane are added slowly. The mixture
is left under agitation at -78ºC for 1 hour, then 30 ml of hexamethylphosphotriamide
are added followed by 3.5 g (20.6 mmol) of ethyl (1R,3R)-3-carboxyaldehyde-2,2-dimethylcyclopropane-1-carboxylate.
The mixture is agitated for 12 hours at ambient temperature, then 45 ml of a saturated
ammonium chloride solution are added. Extraction is then carried out three times with
50 ml of ethyl ether. After drying over anhydrous sodium sulphate, the solution is
evaporated under vacuum (21 mbar/30ºC) and the crude product purified on silica gel
column, with 95/5 (v/v) petroleum ether/ethyl ether as eluent, to obtain an oily product
with an E/Z ratio of 97/3.
b. Synthesis of 2,3,5,6-tetrafluorobenzyl (1R,3R)-3-((E)-Buta-1,3-dienyl)-2,2-dimethylcyclopropane-7-carboxylate
[0036] In a similar way to that described in example 1 part b., 2.38 g (14.3 mmol) of (1R,3R)-3-((E)-buta-1,3-dienyl)-2,2-dimethylcyclopropane-1-carboxylic
acid are added with 3.4 ml (43 mmol) of N-methyl imidazole dissolved in 43 ml of CH
3CN, and reacted with 3.26 g (17.2 mmol) of tosyl chloride dissolved in 19 ml of CH
3CN then with 2.6 ml (14.3 mmol) of 2,3,5,6-tetrafluorobenzyl alcohol dissolved in
16 ml of CH
3CN. After purification on silica gel column with 100/1 (v/v) petroleum ether/ethyl
ether as eluent, 4.58 g of an oily product with an E/Z ratio of 97/3 and a purity
equal to 96.1 % are obtained.
IR (CHCl
3, cm
-1) 3201, 3085, 2930, 1725, 1176.
1H NMR (CDCl
3) δ 7.15-7.07 (m, 1 H, CHAr), 6.37-6.18 (m, 2H, 2CH=), 5.38-5.45 (m, 1 H, vinyl CH),
5.28-5.20 (m, 2H, CH
2O), 5.18 (dd, J
1=2Hz, J
2=12Hz, CH
2=), 4.98 (dd, J
1=2Hz, J
2=12Hz, CH
2=), 2.16-2.07 (m, 1H, CH-cyclopropane), 1.58 (d, 1H,
J=7.5 Hz, CH-cyclopropane), 1.36 (s, 3 H, Me), 1.18 (s, 3H, Me).
13C NMR (CDCl
3) δ 171.05, 147.11-146.36 (m, 2 Aromatic
C-F), 144.6-143.88 (m, 2 Aromatic C-F), 136.44, 136.43, 133.15, 130.93, 115.72, 115.68
(t, J=18Hz, Aromatic-C), 106.59 (t, J=22Hz, Aromatic-CH), 53.55, 36.61, 34.02, 29.79,
21.89, 20.21.
EXAMPLE 3: 2,3,5,6-tetrafluorobenzyl (1R,3R)-3-((E/Z)-Buta-1,3-dienyl)-2,2-dimethylcyclopropane-1-carboxylate
a. Synthesis of (1R,3R)-3-((E/Z)-Buta-1,3-dienyl)-2,2-dimethylcyclopropane-1- carboxylic acid
[0037] In a similar way to that described in example 1 part a., (1R,3R)-3-((E/Z)-Buta-1,3-dienyl)-2,2-dimethylcyclopropane-1-carboxylic
acid is prepared from the corresponding ethyl (1R,3R)-3-carboxyaldehyde-2,2-dimethylcyclopropane-1-carboxylate,
obtained by ozonolysis of (1 R,3R) chrysanthemic acid methyl ester; the ozonolysis
product is then subjected to a Wittig reaction with allyl triphenylphosphonium bromide
as described in
J.Chem. Soc. (C),1076, (1970), followed by alkaline hydrolysis of the ester, after purification
on silica gel column with 100/1 (v/v) petroleum ether/ethyl ether as eluent. The resulting
acid, obtained by acidification of the corresponding salt, is used in the crude form
for the subsequent reaction.
b. Synthesis of 2,3,5,6-tetrafluorobenzyl (1R,3R)-3-((E/Z)-Buta-1,3-dienyl)-2,2-dimethylcyclopropane-1-carboxylate
[0038] In a similar way to that described in example 1 part b., 2.38 g (14.3 mmol) of (1R,3R)-3-((E/Z)-Buta-1,3-dienyl)-2,2-dimethylcyclopropane-1-carboxylic
acid are added with 3.4 ml (43 mmol) of N-methyl imidazole dissolved in 43 ml of CH
3CN, and reacted with 3.26 g (17.2 mmol) of tosyl chloride dissolved in 19 ml of CH
3CN, then with 2.6 ml (14.3 mmol) of 2,3,5,6-tetrafluorobenzyl alcohol dissolved in
16 ml of CH
3CN. After purification on silica gel column with 100/1 (v/v) petroleum ether/ethyl
ether as eluent, 4.64 g of an oily product with a purity equal to 94% are obtained.
IR (CHCl
3, cm
-1) 3200, 3086, 2925, 1725, 1178.
1H NMR (CDCl
3) δ 7.13-7.04 (m, 1 H, CHAr), 6.80-6.65 (m, 1 H, CH=(Z)), 6.33-6.08 (m, 4 vinyl CH
(E)+(Z)), 5.45-5.39 (m, 1 H, vinyl CH (Z)), 5.26-5.10+4.99-4.97 (m, 8 H, 2 vinyl-CH
2 + 2CH
2O
(E)+(Z)), 2.36-2.32 (m, 1H, CH-cyclopropane (Z)), 2.10-2.07. (m, 1H, CH-cyclopropane
(E)), 1.58 (d, 1H,
J = 7.5 Hz, CH-cyclopropane (Z)), 1.54 (d, 1H,
J=5.2 Hz, CH-cyclopropane
(E)), 1.28 (s, 3 H, Me, (Z)), 1.26 (s, 3 H, Me, (E)), 1.1 (s, 6 H, 2Me, (Z)+(E)).
13C NMR (CDCl
3) δ 171.16, 171.07, 147.12-146.84 (m, Aromatic C-F), 146.56-146.37 (m, Aromatic C-F),
144.65-144.37 (m, Aromatic C-F), 144.07-143.84 (m, Aromatic C-F), 136.44, 133.15,
132.23, 131.77, 130.95, 128.32, 118.16, 115.75, 115.37 (t, J=18Hz, Aromatic-C), 106.61
(t, J=22Hz, Aromatic-CH), 53.59, 36.62, 35.04, 34.03, 32.43, 29.81, 29.68, 22.0, 21.91,
20.26, 20.23.
EXAMPLE 4: 2,3,5,6-tetrafluorobenzyl (1R,3R)-3-(Hexa-1,3(E)-5(E/Z)-trienyl)-2,2-dimethylcyclopropane-1-carboxylate
[0039] The compound is prepared from (1R,3R)-3-carboxyaldehyde-2,2-dimethylcyclopropane-1-carboxylate
of 2,3,5,6 tetrafluorobenzyl alcohol, obtained by ozonolysis of the corresponding
chrysanthemic acid ester. Then 30.4 g (100 mmol) of aldehyde are reacted under nitrogen
atmosphere with 40.9 g (120 mmol) of formylmethyltriphenyl phosphonium chloride in
500 ml of benzene in the presence of 15.15 g (150 mmol) of triethylamine at ambient
temperature for 28 hours. The crude (1R,3R)-3-(3(E)-oxopropenyl)-2,2-dimethylcyclopropane-1-carboxylate
of 2,3,5,6 tetrafluorobenzyl alcohol thus obtained, is purified after evaporation
of the solvent at 25ºC/21 mbar on silica gel chromatography column with 2/1 (v/v)
petroleum ether/ethyl acetate as eluent, to obtain 26.7 g of product.
1H NMR (CDCl
3) δ 9.40 (d, 1 H, J=8 Hz, CHO), 7.11-7.03 (m, 1 H, CHAr), 6.49-6.42 (m, 1 H, vinyl-CH),
6.24-6.17 (m, 1H, vinyl CH), 5.24-5.16 (m, 2H, CH
2O), 2.25 (q, 1H, J= 4.8Hz, CH), 1.86 (d, 1H, J = 5.6 Hz, CH), 1.27 (s, 3 H, Me), 1.22
(s, 3 H, Me).
13C NMR (CDCl
3) δ 192.5, 169.8, 154.9, 147.1-146.3 (m, Aromatic C-F), 144.6-143.8 (m, Aromatic C-F),
134.0, 114.9 (t, J=16.6 Hz, Aromatic-C), 106.8 (t, J=22Hz, Aromatic-CH), 60.2, 53.9,
36.0, 35.8, 31.5, 21.9, 20.2, 14.1.
[0040] The product obtained is added slowly at 0ºC to an ether solution (ethyl ether) of
45.7 g (118 mmol) of allyltriphenylphosphonium bromide in 300 ml of anhydrous ethyl
ether, pre-cooled to 0ºC, to which are added 11.1 ml of 1.6 M butyllithium solution
in n-hexane. At the end of the addition the mixture is left for 1 hour at 0ºC then
for 3 hours at ambient temperature. The solution is then filtered and concentrated
at 20ºC/21 mbar, to obtain an oil which is purified on silica gel column with 100/1
petroleum ether/ethyl ether as eluent. 27.2 g of an oily product with 96% purity are
obtained.
IR (CHCl3, cm
-1) 3203, 3083, 2919, 2530, 1721, 1172.
1H NMR (CDCl3) δ 7.11-7.07 (m, 1 H, CHAr), 6.34-6.16 (m, 4 H, vinyl CH), 5.49-5.41 (m, 1
H, vinyl CH), 5.23-5.05 (m, 4 H, 2 vinyl-CH + 2CH2O), 2.13-2.01 (m, 1H, CH-cyclopropane),
1.63-1.56 (m, 1 H, CH-cyclopropane), 1.27 (s, 3 H, Me), 1.12 (s, 3 H, Me).
13C NMR (CDCl3) δ 171.88, 171.08, 137.0, 136.93, 132.8, 132.6, 132.4, 131.9, 131.7, 131.3,
129.6, 129.2, 117.0, 116.8, 106.6 (t, J=22Hz, Aromatic-CH), 64.3, 38.3, 38.1, 34.8,
33.5, 29.7, 28.8, 21.9, 21.4.
EXAMPLE 5: Effectiveness of insecticide in the vapour phase against mosquitoes of
the species Aedes aegypti and Culex quinquefasciatus
[0041] Test units consisting of a paper support 20 cm x 10 cm in size were impregnated with
the compound of example 3 and, for comparative purposes, with the reference compounds
transfluthrin and metofluthrin, at an amount of 5.00 mg/unit for each compound (pure).
[0042] Using a common laboratory stand, the test unit was placed at a height of about 30
cm from the ground along one side of a 20 m
3 room (L 3.00 m x D 2.49 m x H 2.69 m). In order to homogenize the insecticidal air
within the room, a small electric fan was placed on the floor diagonal to the surface
of the unit, in the nearest corner at a distance of about 50 cm from the unit. Three
metal cages (L 8.4cm x Ø 8.0cm x mesh 1.0 mm) for every mosquito species, each containing
20 3-4 day old individuals of mixed sex, were placed along the other three sides of
the room, at a height of 1.80 m from the ground and at a distance of 0.45 m from the
respective walls. During the test the room was kept closed and temperature and humidity
were controlled (T 23-26ºC, RH 49-61%).
[0043] The fan was switched on and left on for 8 continuous hours. The times needed to reach
10%, 50% and 90% insect knock-down (KT10, KT50 and KT90, respectively) were recorded.
[0044] Every 2 hours and up to the 6
th hour after the fan was switched on, new cages were introduced containing insects
(set of 3 cages for each species).
[0045] At the end of the 8
th hour, the percentage of insects knocked down in all the cages was determined, then
the insects were removed from the room and transferred into an uncontaminated atmosphere
within closed containers containing a sugary solution. The percentage mortality was
recorded at the 24
th hour from the start of the test.
[0046] The results obtained are summarized in tables 1 and 2 and the data are averages for
the 3 cages.

EXAMPLE 6: Effectiveness of residual insecticide on surfaces against cockroaches of
the species Blattella germanica
[0047] Solutions of the compound of example 3 in acetone and, for comparison, of the reference
compounds Transfluthrin and Metofluthrin were applied from a distance of 12 cm onto
glazed tiles (Ostara model, 15 x 15 cm = 225 cm
2) by means of a suitable glass sprayer, so as to obtain an applied amount of pure
compound equal to 50 mg/m
2. After treatment the tiles were transferred to and maintained in a closed test room
at controlled temperature and humidity (24-25ºC, RH 50-60%). Glass rings (H 5.5 cm
x Ø 9.5 cm), with their internal surface treated with talc, and each containing 5
cockroaches, were positioned at the centre of the tiles for each of the assessment
times of 24 hours, 3, 7, 10 and 14 days following treatment. For each assessment day,
the insects were maintained on the surface for 24 hours and the time (hours, minutes)
necessary to attain 100% knock-down followed by death, or percentage knock-down at
the end of 24 hours, were recorded. The results obtained are summarized in table 3:

[0048] The activity data presented in tables 1-3 show, for the compound of example 3 in
accordance with formula (I) of the invention, a marked reduction in knock-down time
for the different species tested. In particular, a very obvious increase in activity
compared with the reference insecticides is observed with
Blattella germanica (arthropod). In this respect, table 3 shows a total knock-down (100%) within 15 minutes
of exposure for the compound of the invention; vice-versa, the reference insecticides,
transfluthrin and metofluthrin, achieved only a partial knock-down i.e. between 60
and 80%, at 24 hours after exposure. The compounds of the invention hence demonstrate
a decidedly superior strength; the diversity of the species on which activity is found
also confirms the wide spectrum of action.
EXAMPLE 7: (2-benzyl-4-hydroxymethylfuryl) (1R,3R)-3-((E/Z)-Buta-1,3-dienyl)-2,2-dimethylcyclopropane-1-carboxylate- (comparative)
a. Synthesis of (1R,3R)-3-((E/Z)-Buta-1,3-dienyl)-2,2-dimethylcyclopropane-1-carboxylic acid
[0049] In a similar way to that described in example 1 part a., (1 R,3R)-3-((E/Z)-Buta-1,3-dienyl)-2,2-dimethylcyclopropane-1-carboxylic
acid is prepared from the corresponding ethyl (1R,3R)-3-carboxyaldehyde-2,2-dimethylcyclopropane-1-carboxylate,
obtained by ozonolysis of (1 R,3R) chrysanthemic acid methyl ester; the ozonolysis
product is then subjected to a Wittig reaction with allyl triphenylphosphonium bromide
as described in
J.Chem. Soc. (C),1076, (1970), followed by alkaline hydrolysis of the ester, after purification on silica gel
column with 100/1 (v/v) petroleum ether/ethyl ether as eluent. The resulting acid,
obtained by acidification of the corresponding salt, is used in the crude form for
the subsequent reaction.
b. Synthesis of (2-benzyl-4-hydroxymethylfuryl) (1R,3R)-3-((E/Z)-Buta-1,3-dienyl)-2,2-dimethylcyclopropane-1-carboxylate
[0050] In a similar way to that described in example 1 part b., 4.76 g (28.6 mmol) of (1R,3R)-3-((E/Z)-Buta-1,3-dienyl)-2,2-dimethylcyclopropane-1-carboxylic
acid are added with 6.8 ml (86 mmol) of N-methyl imidazole dissolved in 86 ml of CH
3CN, and reacted with 6.52 g (34.4 mmol) of tosyl chloride dissolved in 38 ml of CH
3CN, then with 5.38 g (28.6 mmol) of 2-benzyl-4-hydroxymethyl-furan dissolved in 32
ml of CH
3CN. After purification on silica gel column with 100/1 (v/v) petroleum ether/ethyl
ether as eluent, 9.1 g of an oily product with a purity equal to 96% are obtained.
IR (CDCl
3, cm
-1) 3200, 3086, 2925, 1725, 1178.
1H NMR (CHCl
3 400 MHz) δ 7.39-7.20 (m, 12 H, (E+Z), Arom-CH+CH= (furan)) 6.80-6.68 (m, 1 H, CH=;
Z), 6.39-6.05 (m, 4H (E+Z),4CH=), 6.02 (s, 1 H, CH= (furan); E), 5.50-5.40 (m, 1 H,
CH=; E), 5.30-5.05 (m, 4H(E+Z), CH=), 5.02-4.81 (m, 5H, (E+Z), 2CH
2+CH=), 3.95 (s, 2H, CH
2 (E)); 2.38-2.32 (m,1H(Z),CH cyclopropane); 2.11-2.03 (m,1H(E), CH cyclopropane);
1.60 (d, 1H(E), J=7.1 Hz, CH), 1.58 (d, 1H(Z), J=7.2 Hz, CH), 1.31 (s, 3H (Z), CH
3) 1.29 (s, 3H (E), CH
3), 1.19 (s, 6 H(E+Z) CH
3).
13C NMR (CDCl
3, 100MHz) δ(E+Z) 171.74, 171.67, 155.58, 140.35, 137.70, 136.52, 132.35, 131.52, 131-34,
128.72, 128.51, 126.57, 121.21, 117.00, 115.57, 107.27, 77.21, 65.83, 57.97, 57.94,
36.28, 35.43, 34.53, 34.42, 34.10, 32.09, 29.45, 29.33, 22.60, 22.32, 22.10, 22.01,
20.32, 20.28, 15.26, 14.04.
EXAMPLE 8: 2,3,5,6-tetrafluoro-4-methoxymethyl benzyl (1R,3R)-3-((E/Z)-Buta-1,3-dienyl)-2,2-dimethylcyclopropane-1-carboxylate
a. Synthesis of (1R,3R)-3-((E/Z)-Buta-1,3-dienyl)-2,2-dimethylcyclopropane-1-carboxylic acid
[0051] In a similar way to that described in example 1 part a., (1R,3R)-3-((E/Z)-Buta-1,3-dienyl)-2,2-dimethylcyclopropane-1-carboxylic
acid is prepared from the corresponding ethyl (1R,3R)-3-carboxyaldehyde-2,2-dimethylcyclopropane-1-carboxylate,
obtained by ozonolysis of (1 R,3R) chrysanthemic acid methyl ester; the ozonolysis
product is then subjected to a Wittig reaction with allyl triphenylphosphonium bromide
as described in
J.Chem. Soc. (C),1076, (1970), followed by alkaline hydrolysis of the ester, after purification
on silica gel column with 100/1 (v/v) petroleum ether/ethyl ether as eluent. The resulting
acid, obtained by acidification of the corresponding salt, is used in the crude form
for the subsequent reaction.
b. Synthesis of 2,3,5,6-tetrafluoro-4-methoxymethyl benzyl (1R,3R)-3-((E/Z)-Buta-1,3-dienyl)-2,2-dimethylcyclopropane-1-carboxylate
[0052] In a similar way to that described in example 1 part b., 4.76 g (28.6 mmol) of (1R,3R)-3-((E/Z)-Buta-1,3-dienyl)-2,2-dimethylcyclopropane-1-carboxylic
acid are added with 6.8 ml (86 mmol) of N-methyl imidazole dissolved in 86 ml of CH
3CN, and reacted with 6.52 g (34.4 mmol) of tosyl chloride dissolved in 38 ml of CH
3CN, then with 6.41 g (28.6 mmol) of 2,3,5,6-tetrafluoro-4-methoxymethyl benzyl alcohol
dissolved in 32 ml of CH
3CN. After purification on silica gel column with 100/1 (v/v) petroleum ether/ethyl
ether as eluent, 9.5 g of an oily product with a purity equal to 96% are obtained.
IR (CHCl
3, cm
-1) 3200, 3095, 2932, 1732, 1178.
1H NMR (CDCl
3 400 MHz) δ 6.78-6.63 (m, 1H, CH=) 6.38-6.16 (m, 3H, CH=; Z+E), 5.38-5.46 (m, 1H CH=,E),
4.95-5.25 (m, 9H, 5CH= + 2CH=; E+Z), 4.58 (m, 4H, (E+Z),2CH
2), 3.41 (s, 6H(E+Z), OCH
3), 2.38-2.31 (m, 1H (Z), CH cyclopropane), 2.15-2.05 (m, 1H (E) CH cyclopropane);
1.58 (d,1H(E),J=7.3 Hz, CH); 1.55 (d, 1H(Z),J=7.2 Hz, CH); 1.50 (s, 3H(Z), CH
3), 1.47 (s, 3H(Z), CH
3), 1.18 (s, 6 H, 2CH
3).
13C NMR (CDCl
3, 100MHz) δ (E+Z) 171.10, 171.02, 146.45, 146.39, 146.31, 146.27, 146.23, 146.17,
143.99, 143.93, 143.87, 143.79, 143.75, 143.69, 136.42, 133.14, 132.22, 131.74, 130.92,
128.30, 118.12, 117.01, 116.83, 116.66, 115.71, 114.99, 114.82, 114.65, 65.78, 61.35,
59.43, 53.48, 36.60, 35.02, 34.02, 32.40, 9.77, 29.65, 21.97, 21.88, 20.25, 20.22,
15.21.
EXAMPLE 9: Effectiveness of insecticide in the vapour phase against mosquitoes of
the species Aedes aegypti and Culex quinquefasciatus
[0053] Test units consisting of a paper support 20 cm x 10 cm in size were impregnated with
the compound of examples 3, 7 and 8 and, for comparative purposes, with the reference
compounds transfluthrin and metofluthrin, at an amount of 5.00 mg/unit for each compound
(pure). Using a common laboratory stand, the test unit was placed at a height of about
30 cm from the ground along one side of a 20 m
3 room (L 3.00 m x D 2.49 m x H 2.69 m). In order to homogenize the insecticidal air
within the room, a small electric fan was placed on the floor diagonal to the surface
of the unit, in the nearest corner at a distance of about 50 cm from the unit. Three
metal cages (L 8.4cm x Ø 8.0cm x mesh 1.0 mm) for every mosquito species, each containing
20 3-4 day old individuals of mixed sex, were placed along the other three sides of
the room, at a height of 1.80 m from the ground and at a distance of 0.45 m from the
respective walls. During the test the room was kept closed and temperature and humidity
were controlled (T 23-26ºC, RH 49-61%).The fan was switched on and left on for 8 continuous
hours. The times needed to reach 10%, 50% and 90% insect knock-down (KT10, KT50 and
KT90, respectively) were recorded.
[0054] Every 2 hours and up to the 6
th hour after the fan was switched on, new cages were introduced containing insects
(set of 3 cages for each species).
[0055] At the end of the 8
th hour, the percentage of insects knocked down in all the cages was determined, then
the insects were removed from the room and transferred into an uncontaminated atmosphere
within closed containers containing a sugary solution. The percentage mortality was
recorded at the 24
th hour from the start of the test.