Oxadiazinediones, their preparation, and their use for the control of insects and arachnids

The present invention relates to novel oxadiazinediones, processes for 
their preparation, and insecticides and acaricides containing these 
compounds as active ingredients. 
German Laid-Open Applications DOS Nos. 2,905,687 and 2,732,115 have 
disclosed that oxadiazinediones have an insecticidal action. 
We have found that oxadiazinediones (I) 
##STR2## 
where R.sup.1 is CH.sub.3, F, Cl or Br, R.sup.2 is H, F or Cl and R.sup.3 
to R.sup.8 are H, F, Cl, Br, CH.sub.3, CF.sub.3, --OCF.sub.3, 
--OCHF.sub.2, --OCF.sub.2 CHCLF, --OCH.sub.3 or --OC.sub.2 H.sub.5, have a 
particularly powerful insecticidal and acaricidal action. 
Compounds where R.sup.1 and R.sup.2 are F, or R.sup.1 and R.sup.2 are Cl, 
or R.sup.1 is Cl and R.sup.2 is F, or R.sup.1 is Cl and R.sup.2 is H are 
preferred. 
The following combinations of substituents R.sup.3 to R.sup.8 are 
preferred: 
(a) If R.sup.3 and R.sup.4 are chlorine or bromine, not less than three of 
the radicals R.sup.5 to R.sup.8 are hydrogen, and one may be halogen; 
(b) if R.sup.3 is hydrogen and R.sup.4 is F, Cl, Br or CF.sub.3, not less 
than two of the radicals R.sup.3 to R.sup.8 are hydrogen, and one or more 
is F, Cl, Br, CF.sub.3, OCF.sub.3 or OCHF.sub.2 ; 
(c) if R.sup.3 and R.sup.4 are hydrogen, not less than two of the radicals 
R.sup.5 to R.sup.8 are F, Br, OCF.sub.3 or OCHF.sub.2 or one or more is Cl 
or CF.sub.3. 
Oxadiazinediones (I) are obtained by reacting a corresponding 
benzoylisocyanate (II) 
##STR3## 
with a corresponding isocyanate (III) 
##STR4## 
in a conventional manner. 
Approximately stoichiometric amounts of the reactants may be used, and the 
reaction is generally carried out at below 160.degree. C., preferably at 
from 80.degree. to 120.degree. C. An effective amount of a catalyst, eg. 
triethylamine or a tin compound, such as dibutyl-tin diacetate, is 
advantageously added. 
Side reactions of the isocyanates may be prevented by an inhibitor, eg. 
phosphorus trichloride. 
In cases where a solvent is to be used, suitable solvents are substances 
which are chemically inert under the reaction conditions, eg. aliphatic 
and aromatic hydrocarbons, which may be chlorinated or nitrated, such as 
benzene, toluene, xylenes, gasoline, chlorobenzenes, 1,2-dichloroethane, 
methylene chloride, chloroform, nitromethane and carbon tetrachloride, 
cyclic and acyclic ethers, such as diethyl ether, dibutyl ether, 
tetrahydrofuran and dioxane, acyclic and cyclic ketones, such as acetone, 
methyl ethyl ketone, methyl isopropyl ketone and cyclohexanone, and 
nitriles, such as acetonitrile and benzonitrile, and mixtures thereof. 
The reaction generally proceeds under atmospheric pressure and can be 
carried out batchwise or continuously. The yield is virtually 
quantitative. 
The oxadiazinediones (I) are obtained in solid form, and as a rule are 
sufficiently pure for the intended purpose. If necessary, they may be 
purified by recrystallization or washing with a solvent, such as ether, 
petroleum ether, cyclohexane or toluene. They are characterized by 
elementary analysis and their melting point and IR and NMR spectra. 
The benzoyl isocyanates (II) can be prepared, for example, in accordance 
with the instructions in J. Org. Chem. 28 (1963), 1805-1811 or J. Agr. 
Food Chem. 21 (1973), 348. 
It is also possible to prepare the phenyl isocyanates by known methods 
(cf., eg., Weygand-Hilgetag, Organisch-Chemische Experimentierkunst, 1970 
or German Laid-Open Application DOS No. 2,538,178). The information 
provided by, for example, Barry et al, Pr. Irish Acad. 53 B, 61, 66, 82 
(1950) may be referred to for the preparation of the diphenyl ethers.