Pesticides

Compounds represented by the formula ##STR1## wherein R.sub.1 is hydrogen or lower alkyl containing 1-4 carbons and PA1 R.sub.2 is a halo-lower alkanoyl or dihalo-lower alkanoyl, said lower alkanoyls each containing 2-6 carbons Useful as pesticides are disclosed.

DESCRIPTION OF THE INVENTION 
The present invention relates to phenylcarbamates, a process for the 
manufacture thereof and pesticidal compositions containing same. The 
invention is also concerned with a method for the control of pests using 
as the active compound said phenylcarbamates. 
The phenylcarbamate compounds provided by the present invention are 
represented by the following formula 
##STR2## 
wherein R.sub.1 is hydrogen or lower alkyl containing 1-4 carbons and 
R.sub.2 is a halo-lower alkanoyl or dihalo-lower alkanoyl, said lower 
alkanoyls each containing 2-6 carbons. 
The compounds within the scope of formula I are useful as pest-control 
agents and are especially suitable for the control of insects. 
According to the process provided by the present invention, the compounds 
within the scope of formula I are manufactured either by (a) reacting, in 
the presence of a base 2,2-dimethyl-4-hydroxy-1,3-benzodioxol represented 
by the formula 
##STR3## 
with a compound represented by the formula 
##STR4## 
wherein Z is chlorine, bromine or iodine and R.sub.1 and R.sub.2 have the 
same significance as in formula I, 
or by (b) reacting a compound represented by the formula 
##STR5## 
wherein X is chlorine, bromine or iodine, WITH AN AMIDE REPRESENTED BY THE 
FORMULA 
##STR6## 
wherein R.sub.1 and R.sub.2 have the same significance as in formula I or 
by (c) reacting in the presence of a base a compound represented by 
formula 
##STR7## 
wherein R.sub.1 has the same significance as in formula I with a compound 
represented by the formula 
##STR8## 
wherein Hal is halogen, R.sub.3 is hydrogen or halogen, Y is chlorine, 
bromine or iodine and n is an integer of from 1 to 5. 
As used in this specification, the term "lower alkyl" includes not only 
straight-chain but also branched-chain hydrocarbon groups containing 1-4 
carbon atoms such as methyl, ethyl, propyl, isopropyl and the like. The 
term "halogen" includes the four halogen atoms fluorine, chlorine, 
bromine and iodine. The terms "halo-lower alkanoyl" and "dihalo-lower 
alkanoyl" include straight-chain and branched-chain alkanoyl groups 
containing 2-6 carbon atoms which are substituted with one or two halogen 
atoms, preferably chlorine, on any position in the alkyl group such as, 
for example, a haloacetyl, dihaloacetyl, halopropionyl, dihalopropionyl, 
halobutyryl or dihalobutyryl group. Preferred are chloroacetyl and 
n-chlorobutyryl, the chlorine being linked with the terminal methyl group. 
Preferred compounds within the scope of formula I are those in which 
R.sub.1 is methyl and R.sub.2 is haloacetyl, preferably chloroacetyl or 
4-chloro-n-butyryl. 
Especially preferred compounds within the scope of formula I are 
2,2-dimethyl-1,3-benzodioxol-4-yl-(chloroacetyl)-methylcarbamate and 
2,2-dimethyl-1,3-benzodioxol-4-yl-(4-chlorobutyryl)-methylcarbamate. 
According to embodiment (a) of the process, the reaction of 
2,2-dimethyl-4-hydroxy-1,3-benzodioxol with a compound of formula III is 
carried out conveniently in the presence of an excess of said compound of 
formula III. The reaction is conveniently carried out in an inert organic 
solvent such as a hydrocarbon, e.g., benzene or toluene, a chlorinated 
hydrocarbon, e.g., methylene chloride, an ether, e.g., diethyl ether and 
the like. As that catalyst there can be used a base such as potassium 
carbonate, sodium carbonate, triethylamine, pyridine and the like. The 
temperature and pressure are not critical; the reaction is preferably 
carried out at a temperature between about 0.degree. C. and the reflux 
temperature of the reaction mixture, preferably at a temperature between 
room temperature and 130.degree. C. 
According to embodiment (b) of the present process, a compound of formula 
IV is reacted with an amide of formula V. This reaction is carried out in 
an inert solvent such as, for example, an ether, preferably diethyl ether, 
dimethylformamide, a chlorinated hydrocarbon, preferably methylene 
chloride or chloroform; dimethyl sulphoxide or benzene. The reaction is 
advantageously carried out at a temperature between 0.degree. C. and the 
boiling point of the reaction mixture. It is especially preferred to carry 
out the reaction at a temperature between 15.degree. C. and 40.degree. C. 
The pressure is not critical; the reaction is preferably carried out in an 
open vessel. The working-up of the reaction mixture is carried out by 
removal of the solvent and recrystallization of the resulting residue by 
conventional means. 
According to embodiment (c) of the present process, a compound of formula 
IV is reacted with a halo-lower alkane carboxylic acid halide or 
dihalo-lower alkane carboxylic acid halide. Examples of such acid halides 
are chloroacetyl chloride, dichloroacetyl chloride, 4-chlorobutyric acid 
chloride and the like. The reaction conditions are not critical and can be 
readily chosen. For example, the reaction can be carried out at room 
temperature or at a temperature above or below room temperature, in each 
case depending on the selected reagent. A preferred temperature range lies 
between room temperature and 130.degree. C. Moreover, the reaction is 
conveniently carried out in a conventional inert organic solvent such as a 
hydrocarbon, e.g., benzene, toluene and the like, a chlorinated 
hydrocarbon, e.g., methylene chloride and the like, an ether, e.g., 
tetrahydrofuran and the like; dimethylformamide, pyridine and the like. 
The starting materials used in the process provided by the present 
invention are either known or can be prepared in an analogous manner to 
the known compounds. 
Pesticidal compositions of this invention contain as the essential active 
ingredient, one or more of the phenylcarbamates of formula I in 
association with a compatible carrier material. The pesticidal 
compositions conveniently contain at least one of the following 
substances: carrier materials, wetting agents, inert diluents and 
solvents. 
The present invention is also concerned with a method for freeing from 
attack a locus subject to or subjected to attack by pests. The method 
comprises applying to said locus an effective amount of a pesticidal 
composition or of one or more of the phenylcarbamates of formula I. Thus, 
for example, the phenylcarbamates of formula I can be used for the control 
of pests on plants and animals and in the soil as well as on objects and 
areas. 
The compounds within the scope of formula I are generally quite of value as 
pesticides. They are especially valuable as insecticides, especially 
against flies, caterpillars, beetles, aphids and Hemiptera. The compounds 
of this invention act as contact insecticides and, to some extent, also 
have systemic activity. The active compounds of this invention are also of 
value for the control of pests in animals. Thus, for example, 
2,2-dimethyl-1,3-benzodioxol-4-yl-(chloroacetyl)-methylcarbamate in a 
concentration of 10.sup.-10 7 g/cm.sup.2 shows an activity of 100% in the 
test against Carpocapsa pomonella in the fifth larval stage and an 
activity of 90% in the test against Musca domestica. 
The compounds within the scope of formula I are, in general, 
water-insoluble and can be made into a ready-for-use form by conventional 
means applicable to insoluble compounds. 
When desired, the compounds of this invention can be dissolved in 
water-immiscible solvent such as, for example, a high-boiling hydrocarbon, 
which conveniently contains dissolved emulsifiers, so that it acts as a 
self-emulsifiable oil upon addition to water. 
The active compounds can also be mixed with a wetting agent, with or 
without an inert diluent, to form a wettable powder which is soluble or 
dispersible in water. They also can be mixed with inert diluents to form a 
solid or pulverous product. 
Inert diluents with which the active compounds of this invention can be 
processed are solid, inert materials, including pulverous or finely 
divided solid materials which as, for example, clays, sands, talc, mica, 
fertilizers and the like. The resulting compositions can be present either 
in the form of dusts or as materials having a larger particle size. 
The wetting agent can be an anionic, cationic or non-ionic compound. 
Typical suitable anionic compounds are, for example, soaps, fatty sulfate 
esters such as dodecyl sodium sulfate, octadecyl sodium sulfate and cetyl 
sodium sulfate, fatty-aromatic sulfonates such as alkylbenzene sulfonates 
or butylnaphthalene sulfonates, complex fatty sulfonates such as the amide 
condensation product of oleic acid and N-methyl-taurin or the sodium 
sulfate of dioctylsuccinate. 
Typical suitable non-ionic wetting agents, for example, condensation 
products of fatty acids, fatty alcohols or fat-substituted phenols with 
ethylene oxide, or fatty acid esters and ethers of sugars or polyvalent 
alcohols or the products which are obtained from the latter by 
condensation with ethylene oxide, or the products which are known as block 
copolymers of ethylene oxide and propylene oxide. 
A typical suitable cationic agent is, for example, cetyltrimethylammonium 
bromide and the like. 
The pesticidal compositions can also be present in the form of an aerosol. 
The aerosol composition can contain in addition to the propellant gas, 
which is suitably a polyhalogenated alkane such as 
dichlorodifluoromethane, as co-solvent and a wetting agent. 
The pesticidal compositions provided by the present invention can contain, 
in addition to one or more of the active compounds of this invention, 
other active insecticides, bactericides and fungicides. 
In their various fields of application, the compounds of this invention can 
be used in different ratios. Thus, for example, for the treatment of 
plants for the control of pests thereon, are conveniently used in an 
amount of about 10-1000 g/ha and for the treatment of animals for the 
control of ectoparasites thereon, the animal is conveniently dipped in a 
solution containing 10-500 parts per million of active compound, or 
sprayed with such a solution. 
The following Examples illustrate the invention.

EXAMPLE 1 
11.2 G. of 2,2-dimethyl-1,3-benzodioxol-4-yl-methylcarbamate are dissolved 
in 100 ml. of toluene and treated with 11.3 g. of chloroacetyl chloride. 
The resulting mixture is heated to reflux for 50 hours and then evaporated 
to dryness. The residue which forms is dissolved in a small amount of 
ether and treated with low-boiling petroleum ether until turbidity 
commences, whereby 1.6 g. of starting material can be recovered. The 
mother liquor is again evaporated to dryness and the resulting residue 
chromatographed over silica gel using methylene chloride for the elution 
to yield 2,2-dimethyl-1,3-benzodioxol-4-yl-(chloroacetyl)-methylcarbamate; 
n.sub.D.sup.25 = 1.518. 
EXAMPLE 2 
11.2 G. of 2,2-dimethyl-1,3-benzodioxol-4-yl-methylcarbamate are dissolved 
in 100 ml. of toluene and treated with 14.7 g. of dichloroacetyl chloride. 
The resulting mixture is heated to reflux for 30 hours and then evaporated 
to dryness. The residue which forms is chromatographed over silica gel 
using methylene chloride for the elution to yield 
2,2-dimethyl-1,3-benzodioxol-4-yl-(dichloroacetyl)-methylcarbamate of 
melting point 115.degree.-116.degree. C. 
EXAMPLE 3 
93 G. of 2,3-(isopropylidenedioxy)-phenyl-methylcarbamate is heated to 
boiling in 883 ml. of xylene and 117.5 g. of 4-chlorobutyric acid 
chloride. A strong stream of nitrogen is conducted through the solution in 
order to expel the liberated hydrogen chloride. After 40 hours, starting 
material can no longer be detected by means of a thin-layer chromatogram. 
The resulting clear brown solution is then evaporated on a rotary 
evaporator at 70.degree. C./112 mm. and the residual brown oil is 
crystallized from alcohol in the cold to yield 
2,2-dimethyl-1,3-benzodioxol-4-yl-(4-chlorobutyryl)-methylcarbamate of 
melting point 61.degree.-62.degree. C. 
EXAMPLE 4 
Spray Powder 
A spray powder is made containing 
50% active ingredient, 
5% high-dispersible silicic acid, 
1% sodium lauryl sulfate, 
2% sodium lignosulfonate (sulfate cellulose spent liquor) and 
42% kaolin. 
The foregoing components are mixed and finely ground in a suitable mill. 
For the production of a finished spray solution, the powder is stirred 
into the desired amount of water.