GB935160A - Pesticides and parasiticides and method for their production - Google Patents

Abstract

The invention comprises a Schiff base carbamate ester having the formula Ar-N=CH-Ar1 wherein Ar and Ar1 represent substituted phenyl radicals and wherein one of Ar and Ar1 is substituted with a methyl-carbamoyloxy radical, and wherein Ar and/or Ar1 may be substituted with a chloro, fluoro, bromo, nitro, lower alkyl, lower alkoxy, or di(lower-alkyl) amino radical. Preferably the esters have the general formula <FORM:0935160/IV(a)/1> wherein X represents a radical on the phenyl ring holding the methylcarbamoyloxy radical, -OCONHCH3, Y and Z represent radicals on the other phenyl ring, and wherein each X and each Y may be a lower alkyl, lower alkoxy, bromo, chloro, fluoro or a nitro radical, Z is a di(lower-alkyl) amino radical, x and y may be from 0 to 3 and z 0 or 1, and wherein each ring contains no more than three substituents selected from -OCONHCH3, X, Y and Z. Among many specified compounds are 4-benzylideneamino-3-tertiary-butylphenyl methyl-carbamate, a -(4-dimethylaminophenylimino)-o-tolyl methyl-carbamate, 4-benzylideneaminophenyl methyl-carbamate, 4-(2,4-dichlorobenzylideneamino)-3,5-xylyl methylcarbamate, 4-benzylideneamino-3,5-xylyl methylcarbamate. The esters may be prepared by (1) the reaction of the corresponding aldehyde compound with an appropriate amine compound, i.e., (a) a benzaldehyde compound with an aminophenol compound, or (b) a hydroxybenzaldehyde compound with an aniline compound to produce an intermediate Schiff base phenol and water of reaction followed by (2) the reaction of the intermediate Schiff base phenol with methyl isocyanate, usually in the presence of a basic catalyst. The selection of the aldehyde compound and the amine compound in step (1) of the reaction above depends on the particular benzene ring in which it is desired to have the methyl-carbamoyloxy radical. Thus, (a) under (1) above is followed if the ultimate product is to have the methylcarbamoyloxy radical on the benzene ring holding the nitrogen of the Schiff base linkage, -N=CH-; however, if the ultimate product is to have the methylcarbamoyloxy radical on the ring holding the carbon of the Schiff base linkage, (b) under (1) above is to be followed. The amine compound above, i.e., the aminophenol compound or the aniline compound, may be employed at its hydrohalide salt. Many examples are given of the starting materials, i.e., benzaldehyde compounds, aminophenol compounds, hydroxybenzaldehyde compounds and aniline compounds. In an example 4-benzylideneamino- 3- tertiarybutylphenol methylcarbamate of the general formula <FORM:0935160/IV(a)/2> is prepared by adding benzaldehyde to 4-amino-3-tertiary-butylphenol and treating the mixture with sodium acetate trihydrate to produce an oily phase which crystallized to produce a 4-benzylideneamino-3-tertiary-butyl-phenol to a solution of which was added methyl isocyanate and a few drops of triethylamine when the 4-benzylideneamino-3-tertiary-butylphenol methylcarbamate precipitated on standing. Anti-helmintic compositions comprise as active ingredients the above compounds and are used in liquid or solid form by applying to the animals attacked or the food to be ingested by them.ALSO:Pesticidal compositions, i.e. for destroying or controlling undesirable insects, trash fish, aquatic pests, mites, helminths, microbes, and other pests in their various stages comprise as an active ingredient a Schiff base carbamate ester having the formula Ar-N = CH-Ar1, wherein Ar and Ar1 represent substituted phenyl radicals and wherein one of Ar and Ar1 is substituted with a methylcarbamoyloxy radical, and wherein Ar and/or Ar1 may be substituted with one or more of chloro, fluoro, bromo, nitro, lower alkyl, lower alkoxy, or di (lower-alkyl) amino radicals and one or more inert liquid or solid carriers or adjuvants. Preferably the carbamate ester has the general formula <FORM:0935160/VI/1> wherein X represents a radical on the phenyl ring holding the methylcarbamoyloxy radical, -OCONHCH3, Y and Z represent radicals on the other phenyl ring, and wherein each X and each Y may be a lower alkyl, lower alkoxy, bromo, chloro, fluoro, or a nitro radical, Z is a di (lower-alkyl) amino radical, x and y may be from 0 to 3 and z 0 or 1, and wherein each ring contains no more than three substituents selected from -OCONHCH3, X, Y and Z. The active ingredients may be mixed with solid or liquid diluents and may include dispersing and emulsifying agents. Among many specified active ingredients are 4-benzylideneamino-3-tertiary - butylphenyl methylcarbamate, 4-benzylideneamino-3,5-xylyl methylcarbamate, 3 - tertiary - butyl - 4 - (4 - chlorobenzylideneamino) phenyl methylcarbamate, 4-(2,4-dichlorobenzylideneamino) - 3,5 - xylyl methylcarbamate, 4 - (4 - chlorobenzylideneamino)-3,5-xylyl methylcarbamate and 4-(4-dimethylaminobenzylideneamino) - 3,5 - xylyl methylcarbamate. The invention also includes a method of applying to parasites or pests in particular to insects fungi, helminths, mites, bacteria, aphids, or nematodes or to their habitats or food, respectively a parasiticidal amount of the Schiff base carbamate ester referred to above.