| 摘要 |
The invention comprises 2,6-dichlorophenyl-nitromethane, its a -monochloro and -monobromo derivatives and the corresponding aci-tautomers, as well as the alkali metal, ammonium and hydrocarbyl derivatives of the aci-form. Reaction of a 2, 6-dichlorobenzyl halide with an inorganic nitrite gives the phenylnitromethane in admixture with the corresponding benzyl nitrite and benzyl alcohol; a nitrite ester scavenger is preferably used in the reaction, various phenols and amines being specified. The alkali metal salts are prepared from 2,6-dichlorophenylnitromethane with alkali metal carbonate, hydroxide or alkoxide; the ammonium salts are obtained from the aci-tautomer (formed from alkali metal salt with acid at 0 DEG C. or below) by treatment with ammonia, an amine or a heterocyclic nitrogenous base. The said monochloro and monobromo compounds are prepared from alkali metal salt of aci-tautomer with chlorine or bromine in an inert solvent. The hydrocarbyl derivatives are prepared by reacting the said alkali metal salt with a hydrocarbyl halide, an alkyl arylsulphonate or a dialkyl sulphate. The alkali metal salt, by treatment with acetyl chloride and simultaneously or subsequently ammonia, gives 2,6-dichloroa -amino benzaldoxime; its hydrochloride forms by reaction with HCl in dry ether. By product 2,6-dichlorobenzyl alcohol (in admixture with the phenylnitromethane) may be converted to the benzyl chloride with thionyl chloride. Specification 953,554 is referred to.ALSO:Herbicidal compositions comprise 2,6-dichlorophenylnitromethane, or its a -monochloro or -monobromo derivative, the corresponding aci-tautomers or the alkali metal, ammonium or hydrocarbyl derivatives of the aci-form, together with a solid or liquid carrier and/or a surface active agent; they may be formulated as dusts, wettable powders, emulsifiable concentrates or aqueous dispersions or emulsions of oil in water or water in oil type. The Specification lists the usual solid and liquid carriers, and surface active agents; sodium polyphosphates, cellulose ethers and unspecified sequestering agents, pesticides (e.g. herbicides) and non-volatile oil is also mentioned. The invention comprises also a method of controlling wild oats in a growing barley crop by pretreating the crop area containing wild oat and barley seeds with 2,6-dichlorophenylnitromethane. Resinous and waxy carriers are specified, bitumen and asphaltite.
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