N-polyhalobenzyl-pyrazole carboxamides endowed with acaricidal and insecticidal activity

Amides of pyrazolecarboxy acids having the general formula (I): ##STR1## exhibiting a high insecticidal and acaricidal activity.

The present invention relates to novel amides of pyrazole carboxy acids, 
More particularly, the present invention relates to amides of pyrazole 
carboxy acids displaying a high acaricidal and insecticidal activity, a 
process for preparing them, and their use for controlling harmful mites 
and insects in agricultural, civil and zootechnic fields. 
Amides of pyrazole carboxy acids displaying acaricidal and insecticidal 
activity are already known from European patent application Nos. 289,879; 
307,801; 329,020; 365,925; 405,808; 462,573; 521,409. However, the 
compounds disclosed in the above patent applications display only a 
secondary insecticidal activity. 
The present Applicant has now found that if the amidic nitrogen atom is 
replaced by a poly-halogenated benzyl group, compounds are obtained which 
display a surprisingly high acaricidal and insecticidal activity, higher 
than that displayed by the corresponding N-benzyl pyrazole carboxamides 
known from the prior art. 
Therefore, the present invention provides amides of pyrazole carboxy acids 
having the general formula (I): 
##STR2## 
wherein: R.sub.1 and R.sub.2 represent, each independently, a linear or 
branched C.sub.1 -C.sub.4 alkyl radical; 
R.sub.x represents a hydrogen atom, a halogen atom, a linear or branched 
C.sub.1 -C.sub.4 alkyl or haloalkyl radical, a C.sub.1 -C.sub.2 alkoxy or 
haloalkoxy radical; or when R.sub.2 and R.sub.x are taken jointly, they 
represent a moiety 
##STR3## 
in which R represents a hydrogen atom or a C.sub.1 -C.sub.3 alkyl radical 
and n is a number between 1 and 2; 
R.sub.3, R.sub.4 and R.sub.5 represent, each independently, a hydrogen atom 
or a linear or branched C.sub.1 -C.sub.4 alkyl radical; 
X.sub.1, X.sub.2, X.sub.3 and X.sub.4 represent, each independently, a 
halogen atom; or, when at least two from X.sub.1 to X.sub.4 represent 
halogen atoms, a hydrogen atom; 
R.sub.y represents a halogen atom, a linear or branched C.sub.1 -C.sub.8 
alkyl or haloalkyl radical, a linear or branched C.sub.1 -C.sub.8 alkoxy 
or haloalkoxy radical, a linear or branched C.sub.3 -C.sub.8 alkoxy alkoxy 
radical, a C.sub.3 -C.sub.8 cycloalkoxy radical, a C.sub.4 -C.sub.8 
cycloalkylalkoxy radical, a C.sub.1 -C.sub.8 alkylthio radical, a 
trimethylsilyl radical; a linear or branched C.sub.3 -C.sub.8 alkoxyalkyl 
or haloalkoxyalkyl radical; a C.sub.2 -C.sub.8 alkylamino or dialkylamino 
radical; or when all of X.sub.1 -X.sub.4 are halogen atoms, R.sub.y 
represents a phenoxy or a phenylthio radical, with said radicals being 
optionally substituted with halogen atoms, linear or branched alkyl or 
haloalkyl C.sub.1 -C.sub.4 radicals, linear or branched C.sub.1 -C.sub.4 
alkoxy or haloalkoxy radicals. 
The compounds of general formula (I) exhibit high insecticidal and 
acaricidal activity. 
Preferred compounds of general formula (I) according to the present 
invention are those in which X.sub.1, X.sub.2, X.sub.3 and X.sub.4 
represent a fluorine atom, with the other substituents having the meanings 
disclosed hereinabove. 
Examples of compounds of general formula (I) which exhibit insecticidal and 
acaricidal activity are: 
N-(4-methyl-2,3,5,6-tetrafluorobenzyl)-4-chloro-3-ethyl-1-methylpyrazole-5- 
carboxamide; 
N-(4-n-propyl-2,3,5,6-tetrafluorobenzyl)-4-chloro-3-ethyl-1-methylpyrazole- 
5-carboxamide; 
N-(4-n-propyl-2,3,5,6-tetrafluorobenzyl)-4-chloro-1,3-dimethylpyrazole-5-ca 
rboxamide; 
N-(4-n-butyl-2,3,5,6-tetrafluorobenzyl)-4-chloro-3-ethyl-1-methylpyrazole-5 
-carboxamide; 
N-(4-n-butyl-2,3,5,6-tetrafluorobenzyl)-4-chloro-1,3-dimethylpyrazole-5-car 
boxamide; 
N-(4-n-butyl-2,3,5,6-tetrafluorobenzyl)-2,6-dimethyl-2,4,5,6-tetrahydrocycl 
opentapyrazole-3-carboxamide; 
N-(4-isobutyl-2,3,5,6-tetrafluorobenzyl)-4-chloro-3-ethyl-1-methylpyrazole- 
5-carboxamide; 
N-(4-isobutyl-2,3,5,6-tetrafluorobenzyl)-4-chloro-1,3-dimethylpyrazole-5-ca 
rboxamide; 
N-(4-tert.-butyl-2,3,5,6-tetrafluorobenzyl)-4-chloro-3-ethyl-1-methylpyrazo 
le-5-carboxamide; 
N-(4-tert.butyl-2,3,5,6-tetrafluorobenzyl)-4-chloro-1,3-dimethylpyrazole-5- 
carboxamide; 
N-(4-tert.butyl-2,3,5,6-tetrafluorobenzyl)-2,6-dimethyl-2,4,5,6-tetrahydroc 
yclopentapyrazole-3-carboxamide; 
N-[4-(2,2-dimethylpropyl)-2,3,5,6-tetrafluorobenzyl]-4-chloro-3-ethyl-1-met 
hylpyrazole-5-carboxamide; 
N-[4-(2,2-dimethylpropyl)-2,3,5,6-tetrafluorobenzyl]-4-chloro-1,3-dimethylp 
yrazole-5-carboxamide; 
N-[4-(2,2-dimethylpropyl)-2,3,5,6-tetrafluorobenzyl]-2,6-dimethyl-2,4,5,6-t 
etrahydrocyclopentapyrazole-3-carboxamide; 
N-(4-n-pentyl-2,3,5,6-tetrafluorobenzyl)-4-chloro-3-ethyl-1-methylpyrazole- 
5-carboxamide; 
N-(4-n-pentyl-2,3,5,6-tetrafluorobenzyl)-4-chloro-1,3-dimethylpyrazole-5-ca 
rboxamide; 
N-(4-n-pentyl-2,3,5,6-tetrafluorobenzyl)-2,6-dimethyl-2,4,5,6-tetrahydrocyc 
lopentapyrazole-3-carboxamide; 
N-[4-(3-methylbutyl)-2,3,5,6-tetrafluorobenzyl]-4-chloro-3-ethyl-1-methylpy 
razole-5-carboxamide; 
N-[4-(3-methylbutyl)-2,3,5,6-tetrafluorobenzyl]-4-chloro-1,3-dimethylpyrazo 
le-5-carboxamide; 
N-[4-(3-methylbutyl)-2,3,5,6-tetrafluorobenzyl]-2,6-dimethyl-2,4,5,6-tetrah 
ydrocyclopentapyrazole-3-carboxamide; 
N-(4-n-propoxy-2,3,5,6-tetrafluorobenzyl)-4-chloro-3-ethyl-1-methylpyrazole 
-5-carboxamide; 
N-(4-n-propoxy-2,3,5,6-tetrafluorobenzyl)-4-chloro-1,3-dimethylpyrazole-5-c 
arboxamide; 
N-(4-isopropoxy-2,3,5,6-tetrafluorobenzyl)-4-chloro-3-ethyl-1-methylpyrazol 
e-5-carboxamide; 
N-(4-isopropoxy-2,3,5,6-tetrafluorobenzyl)-4-chloro-1,3-dimethylpyrazole-5- 
carboxamide; 
N-(4-n-butoxy-2,3,5,6-tetrafluorobenzyl)-4-chloro-3-ethyl-1-methylpyrazole- 
5-carboxamide; 
N-(4-n-butoxy-2,3,5,6-tetrafluorobenzyl)-4-chloro-1,3-dimethylpyrazole-5-ca 
rboxamide; 
N-(4-n-butoxy-3,5-dichlorobenzyl)-4-chloro-3-ethyl-1-methylpyrazole-5-carbo 
xamide; 
N-(4-isobutoxy-2,3,5,6-tetrafluorobenzyl)-4-chloro-3-ethyl-1-methylpyrazole 
-5-carboxamide; 
N-(4-isobutoxy-2,3,5,6-tetrafluorobenzyl)-4-chloro-1,3-dimethylpyrazole-5-c 
arboxamide; 
N-(4-isobutoxy-3,5-dichlorobenzyl)-4-chloro-3-ethyl-1-methylpyrazole-5-carb 
oxamide; 
N-(4-sec.butoxy-2,3,5,6-tetrafluorobenzyl)-4-chloro-3-ethyl-1-methylpyrazol 
e-5-carboxamide; 
N-(4-sec.butoxy-2,3,5,6-tetrafluorobenzyl)-4-chloro-1,3-dimethylpyrazole-5- 
carboxamide; 
N-[4-(2,2-dimethylpropoxy)-2,3,5,6-tetrafluorobenzyl]-4-chloro-3-ethyl-1-me 
thylpyrazole-5-carboxamide; 
N-[4-(2,2,-dimethylpropoxy)-2,3,5,6-tetrafluorobenzyl]-4-chloro-1,3-dimethy 
lpyrazole-5-carboxamide; 
N-[4-(3-methylbutoxy)-2,3,5,6-tetrafluorobenzyl]-4-chloro-3-ethyl-1-methylp 
yrazole-5-carboxamide; 
N-[4-(3-methylbutoxy)-2,3,5,6-tetrafluorobenzyl]-4-chloro-1,3-dimethylpyraz 
ole-5-carboxamide; 
N-[4-(3-methylbutoxy)-3,5-dichlorobenzyl]-4-chloro-3-ethyl-1-methylpyrazole 
-5-carboxamide; 
N-(4-cyclopentoxy-2,3,5,6-tetrafluorobenzyl)-4-chloro-3-ethyl-1-methylpyraz 
ole-5-carboxamide; 
N-(4-cyclopentoxy-2,3,5,6-tetrafluorobenzyl)-4-chloro-1,3-dimethylpyrazole- 
5-carboxamide; 
N-(4-cyclopropylmethoxy-2,3,5,6-tetrafluorobenzyl)-4-chloro-3-ethyl-1-methy 
lpyrazole-5-carboxamide; 
N-(4-cyclopropylmethoxy-2,3,5,6-tetrafluorobenzyl)-4-chloro-1,3-dimethylpyr 
azole-5-carboxamide; 
N-[4-(2,2,2-trifluoroethoxy)-2,3,5,6-tetrafluorobenzyl]-4-chloro-3-ethyl-1- 
methylpyrazole-5-carboxamide; 
N-[4-(2,2,2-trifluoroethoxy-2,3,5,6-tetrafluorobenzyl]-4-chloro-l,3-dimethy 
lpyrazole-5-carboxamide; 
N-[4-(2,2,3,3-tetrafluoropropoxy)-2,3,5,6-tetrafluorobenzyl]-4-chloro-3-eth 
yl-1-methylpyrazole-5-carboxamide; 
N-[4-(2,2,3,3-tetrafluoropropoxy)-2,3,5,6-tetrafluorobenzyl]-4-chloro-l,3-d 
imethylpyrazole-5-carboxamide; 
N-[4-(2,2,3,3,4,4,5,5-octafluoropentoxy)-2,3,5,6-tetrafluorobenzyl]-4-chlor 
o-3-ethyl-1-methylpyrazole-5-carboxamide; 
N-[4-(2,2,3,3,4,4,5,5-octafluoropentoxy)-2,3,5,6-tetrafluorobenzyl]-4-chlor 
o-1,3-dimethylpyrazole-5-carboxamide; 
N-(4-n-butylthio-2,3,5,6-tetrafluorobenzyl)-4-chloro-3-ethyl-1-methylpyrazo 
le-5-carboxamide; 
N-(4-n-butylthio-2,3,5,6-tetrafluorobenzyl)-4-chloro-1,3-dimethylpyrazole-5 
-carboxamide; 
N-(2,3,5,6-tertrafluoro-4-trimethylsilylbenzyl)-4-chloro-3-ethyl-1-methylpy 
razole-5-carboxamide. 
The present invention also provides a process for preparing the compounds 
of general formula (I). 
The compounds of general formula (I) can be obtained by means of a process 
which comprises reacting a derivative of a pyrazole-carboxy acid having 
the general formula (II) 
##STR4## 
wherein R.sub.1, R.sub.2 and R.sub.x have the same meaning as disclosed 
above, Z represents a halogen atom, such as chlorine or bromine, a hydroxy 
radical or a linear or branched C.sub.1 -C.sub.4 alkoxy radical, with a 
benzylamine of general formula (III): 
##STR5## 
wherein R.sub.3, R.sub.4, R.sub.5, X.sub.1, X.sub.2, X.sub.3, X.sub.4 and 
R.sub.y have the same meaning as disclosed above. 
The reaction can be carried out in the presence or absence of a base and in 
the presence or absence of a solvent. 
In the case where Z represents a chlorine or bromine atom, the reaction is 
preferably carried out in the presence of an organic or inorganic base and 
in the presence of a solvent, at a temperature within the range of from 
0.degree. C. to the boiling temperature of the reaction mixture (the 
solvent plus the base and both above disclosed reactants). 
Examples of organic bases useful for carrying out the above process are 
triethylamine, pyridine, N,N-dimethylaminopyridine, etc. 
Examples of inorganic bases are sodium hydroxide, potassium hydroxide, 
sodium carbonate, potassium carbonate, etc. 
Examples of solvents useful for carrying out the process disclosed above 
are benzene, toluene xylene, acetone, methyl ethyl ketone, chloroform, 
methylene chloride, ethyl acetate, ethyl ether, tetrahydrofuran, dioxane, 
acetonitrile, N,N-dimethylformamide, N-methylpyrrolidone, dimethyl 
sulfoxide, water etc. 
In the case where Z represents a hydroxy or alkoxy radical, the reaction is 
preferably carried out in the absence of any bases. In that case, the 
reaction can be carried out either in the absence or in the presence of a 
high-boiling solvent such as N,N-dimethylformamide, N-methylpyrrolidone, 
dimethyl sulfoxide, etc., at a temperature within the range of from 
150.degree. C. to 250.degree. C., 
The derivatives of pyrazole carboxy acid of general formula (II) are known 
from technical literature and can be prepared for example according to 
that reported in "Bulletin de la Societe Chimie de France", 1966, p. 293; 
in "Farmaco Ed. Sc.", Vol. 22, 1967, p. 692 and in "Annalen der Chemie", 
Vol 598, 1956, p. 186. 
The benzylamines of general formula (III) can be prepared according to well 
known methods of practical organic synthesis, such as described for 
example in "Beilstein Handbuch der Organischen Chemie", Vol 12, Chapter 
III, p. 2343. 
The compounds of general formula (I) according to the present invention 
display a high level of acaricidal and insecticidal activity against 
insect and mite adults, larvae and their eggs dangerous in agricultural, 
civil and zootechnic fields. 
In particular, the compounds of general formula (I) are active against 
important species of Coleoptera (Leptinotarsa decemlineata, Callosobruchus 
chinensis, and so forth), Hemyptera (Macrosiphum euphorbiae, Myzus 
persicae, Psylla pyricola, and so forth), Diptera (Aedes Aegypti, Musca 
domestica, and so forth), Lepidoptera (Spodoptera littoralis, Chilo 
suppressalis, and so forth), and several families of mites, e.g., 
Tetranychus spp. (Tetranychus urticae, Tetranychus telarius, Panonychus 
ulmi, Panonychus citri, and so forth), Eryophyes spp. (Phytoptus 
avellanae, Eryophyes vitis, Erophyes pyricola, and so forth; Tarsonemidae 
Steneotarsonemus pallidus, and so forth). 
At the same time, the compounds of general formula (I) display a low level 
of toxicity for a large number of useful insects and mites, mammals, 
fishs, amphibia and birds and do not exhibit phytotoxicity. 
Due to their positive characteristics, the compounds of general formula (I) 
can be advantageously used to defend from insect and mite pests in crops 
of agricultural and horticultural interest, and domestic animals and 
husbandry livestock, as well as sites frequented by humans. 
For practical use in agricultural and in other fields, it is often 
advantageous to use compositions of insecticidal and acaricidal activity 
containing one or more compounds of general formula (I) as active 
substance. 
Compositions can be used which are in the form of dry dusts, wettable 
powders, emulsifiable concentrates, microemulsions, pastes, granular 
formulations, solutions, suspensions etc. The selection of formulation 
type will depend on the contemplated specific use. 
The compositions are prepared according to well known methodologies, for 
example by diluting or dissolving the active substance with a solvent 
and/or a solid diluent, possibly in the presence of surfactants. 
Suitable solid inert diluents or carriers include China clay, alumina, 
silica, talc, bentonite, chalk, quartz, dolomite, attapulgite, 
montmorillonite, diatomaceous earth, cellulose, starch, etc. 
Suitable liquid inert diluents include, in addition to water, organic 
solvents such as aromatic hydrocarbons (xylenes, blends of alkylbenzenes, 
and so forth), or aliphatic hydrocarbons (hexane, cyclohexane, and so 
forth), as well as halogenated aromatic hydrocarbons (chlorobenzene, and 
so forth), alcohols (methanol, propanol, butanol, octanol, and so forth), 
esters (isobutyl acetate, and so forth), ketones (acetone, cyclohexanone, 
acetophenone, isoforone, ethyl amyl ketone, and so forth), or vegetable or 
mineral oils, or mixtures thereof, etc. 
Suitable surfactants include wetting agents and emulsifiers of non-ionic 
type (polyethoxylated alkyl phenols, polyethoxylated fatty alcohols, 
etc.), anionic type (alkylbenzene sulfonates, alkyl sulfonates, etc.) and 
cationic types (quaternary alkylammonium salts, etc.) 
Furthermore, dispersants (e.g., lignine and its salts, cellulose 
derivatives, alginates, etc.) and stabilizers (e.g., antioxidants, U.V. 
light absorbants, etc.), can be added. 
In order to extend the active range of the above said compositions, 
additional active agents can be added such as other insecticides or 
acaricides, herbicides, fungitides, fertilizers. 
The concentration of active substance in the above said compositions may 
vary within a wide range according to the active compound, the 
applications they are destined to, the environmental conditions, and the 
type of formulation adopted. 
In general, the concentration of active substance is within the range of 
from 1% to 90%, preferably of from 5% to 40%. 
Also the application rates vary depending on several factors such as the 
type of pest and the degree of infestation, the type of composition used, 
and climatical and environmental factors. 
For practical uses in agriculture, active compound application rates within 
the range of from 10 g to 500 g per hectare provide a sufficient 
protection. 
The following examples are reported for illustrative purposes and do not 
limit the present invention. 
In the spectra of protonic nuclear magnetic resonance (.sup.1 H-NMR) 
reported in the following examples, the following abbreviations were used: 
s=singlet; d=doublet; t=triplet; q=quartet; tt=triplet of triplets; 
bt=broad triplet; m=multiplet, or complex signal.