The present invention is directed to 1-benzoyl-3-(alkoxy- or alkylthiopyridinyl)urea compounds useful as insecticides.

SUMMARY OF THE INVENTION 
More particularly, the present invention is directed to novel compounds of 
the formula 
##STR1## 
wherein each R is independently chloro, fluoro, methyl, or methoxy; 
R.sup.1 is H, Cl, CH.sub.3, or C.sub.2 H.sub.5 ; X is O, S, 
##STR2## 
and R.sup.2 is alkyl of C.sub.1 -C.sub.5, alkenyl of C.sub.3 -C.sub.5 
containing no .alpha., .beta.-unsaturation, mono- or dibromo-C.sub.1 
-C.sub.5 alkyl, chloroalkyl of C.sub.1 -C.sub.5, fluoroalkyl of C.sub.1 
-C.sub.5, cycloalkyl of C.sub.4 -C.sub.6, or alkoxyalkyl of a total of 
C.sub.2 -C.sub.5 ; and the acid addition salts thereof. 
The present invention is also directed to methods and compositions 
comprising the above compounds as insecticides. 
DETAILED DESCRIPTION OF THE INVENTION 
For the purposes of the present application, the compounds of this 
invention are named as substituted ureas, with numbering as follows: 
##STR3## 
Thus, the compounds are named as 1-(2,6-disubstituted 
benzoyl)-3-(5-R.sup.1 -6-X-R.sup.2 -3-pyridinyl)ureas, or acid addition 
salts thereof. 
In the foregoing definition, fluoralkyl of C.sub.1 -C.sub.5 refers to 
C.sub.1 -C.sub.5 alkyl bearing from one fluorine to as many fluorine as 
the alkyl permits, i.e., perfluorinated. Representative perfluoroalkyl 
radicals include trifluoromethyl, 2,2,2-trifluoroethyl, 
1-methyl-2,2,3,3,3-pentafluoropropyl, 
2-methyl-1,1,1,3,3,3-hexafluoro-2-propyl, 2,2,3,3,4,4,4-heptafluorobutyl, 
3,3,4,4,5,5,5-heptafluoro-2-pentyl, 2,2,-3,3,4,4,5,5-octafluoropentyl, 
3,3,4,4,4-pentafluoro-2-butyl, 2,2,3,3,3-pentafluoropropyl, 
perfluoro-tert-butyl, 2,2,3,3-tetrafluoropropyl, and 
2-(trifluoromethyl)-2-propyl. Similarly, chloroalkyl of C.sub.1 -C.sub.5 
refers to C.sub.1 -C.sub.5 alkyl bearing from one chlorine to as many 
chlorine as the alkyl permits, i.e., perchlorinated. Representative 
radicals include chloromethyl, dichloromethyl, trichloromethyl, 
2,2,2-trichloroethyl, 1,1,1-trichloro-2-propyl, and 
1,1,1-trichloro-2-methyl-2-propyl; generally, mono-, di-, or trichloro 
substituted radicals are preferred. 
The compounds of the present invention are readily prepared by the reaction 
of a benzoyl isocyanate of the formula 
##STR4## 
with a 3-aminopyridine of the formula 
##STR5## 
The reaction is a known type of reaction, cf. U.S. Pat. No. 3,748,356. The 
reaction is conveniently conducted in an organic solvent such as ethyl 
acetate, at room temperature, and with equimolar amounts of the reactants. 
The acid addition salts are prepared by reacting a product with the desired 
acid in conventional procedures. Acids having a pKa of 3 or lower are 
preferred, and generally the mineral acids are preferred. 
The benzoyl isocyanates which serve as starting materials are prepared by 
the reaction of the corresponding benzamide with oxalyl chloride, by the 
method of Speziale et al., J. Org. Chem. 27, 3742 (1962). 
The 3-aminopyridine starting materials are prepared from the corresponding 
halonitropyridines 
##STR6## 
The halonitropyridine is first condensed with an alcohol or thiol of the 
formula HX-R.sup.2 and the resulting compound 
##STR7## 
is then reduced. The condensation is conducted in a solvent such as DMF, 
DMSO, THF, etc., and in the presence of a base, such as triethylamine, 
KOH, LiOH, NaH, etc., to serve as a hydrogen halide acceptor. Preferred 
conditions are equimolar amounts of the reactants in DMF, at room 
temperature, and with lithium hydroxide as base. The reduction can be 
carried out in any of various prior art procedures, including SnCl.sub.2 
/HCl, catalytic hydrogenation, and powdered iron with ammonium chloride. 
Preferred conditions are powdered iron and ammonium chloride. 
For final products wherein 
##STR8## 
it is preferred to oxidize the sulfur of the 6-SR.sup.2 -3-aminopyridine 
starting material and employ it in the reaction with the benzoyl 
isocyanate, to obtain the product wherein 
##STR9## 
Many of the halonitropyridines are commercially available and all are 
prepared in known procedures. See Acharya et al., Chem. Abst. 58, 5623c 
(1963); Batkowski, Chem. Abst. 70, 106327x (1969); and Hawkins et al., J. 
Org. Chem. 14, 328 (1949). The synthesis of these and numerous other 
pyridine compounds has been well reviewed in Pyridine and Its Derivatives, 
ed. by Klingsberg, especially Parts 2 and 3 (Interscience Publishers, New 
York, N.Y. 1961 and 1962). 
Most of the alkanols and cycloalkanols, and many of the alkanethiols and 
cycloalkanethiols are also commercially available. All can be prepared in 
prior art procedures. A convenient procedure for converting an alcohol to 
a alkanethiol, or a cycloalkanol to a cycloalkanethiol, is that of Newman 
et al., J. Org. Chem. 31, 3980 (1966). 
Preferred compounds of the present invention are 
(1) those wherein R is in both occurrences the same moiety and is either 
chloro, fluoro, or methoxy; and 
(2) those wherein R.sup.2 is a branched C.sub.3 -C.sub.5 alkyl, especially 
tert-butyl, and wherein R.sup.2 is cyclohexyl.