GB819127A - Herbicidal amine salts of chlorobenzoic acids - Google Patents

Abstract

The invention comprises compounds of the general formula <FORM:0819127/IV (b)/1> where n is 1-5, R1 is C1 or C2 alkyl which may be substituted with an amino group, or C2-C4 branched or straight chain alkanol radical, and R2 and R3 which may be the same or different are hydrogen or as R1. The compounds of the invention may be prepared by reacting an amine of formula N-N1R2R3 with <FORM:0819127/IV (b)/2> at ambient temperature to 49 DEG C., at atmospheric pressure. The amine is preferably slowly added to a slurry of the acid in water, and the mixture held at the reaction temperature until the pH of the solution is 6.5-7.5. Small increments of acid or amine may be added if the pH of the solution does not fall within this range after an hour. Mixtures of polychlorobenzoic acids may be used as starting materials, e.g. mixtures of 2,5-dichloro; 2,3,5; 2,3,6; 2,4,5; trichloro, 2,3,4,5; and 2,3,5,6; tetrachloro, and pentachloro benzoic acids. Amines specified as starting materials are mono-, di- and trimethyl and -ethyl amines, mono-, di- and tri-ethanol and propanol amines, N,N-dimethyl ethanol amine, N,N-diethyl ethanol amine; N-aminoethyl ethanol amine, N,N-dimethyl propanol amine, 2-amino butanol-1, and mixtures thereof. Examples are given.ALSO:The invention comprises herbicidal compositions containing compounds of general formula <FORM:0819127/VI/1> where n is 1-5, R1 is C1 or C2 alkyl which may be substituted with an amino group, or C2-C4 branched or straight chain alkanol radical and R2 and R3 which may be the same or different are hydrogen or as R1. Polychlorobenzoic acids specified are 2,5-dichloro, 2,3,5; 2,3,6; 2,4,5; trichloro, 2,3,4,5; and 2,3,5,6; tetrachloro and pentachloro benzoic acids and mixtures thereof. Amines specified are mono-, di- and tri-ethanol and propanolamines, N,N-dimethyl ethanol amine, N,N-diethyl ethanol amine, N-aminoethyl ethanol amine, N,N-dimethyl propanol amine, 2-amino butanol-1 and mixtures thereof. Suitable carriers for the above compounds are sequestering agents such as water-soluble salts of citric acid and ethylene diamine tetra-acetic acid or mixtures thereof, preferably in an amount of 0.1 to 2.0 per cent by weight of the composition.