GB653452A - Improvements in or relating to a method of preparing an (n,n-diaryl) amino acid ester - Google Patents

Abstract

A b -(N,N-diaryl)-aminopropionic acid ester is prepared by reaction of a diarylamine with either an ester of acrylic acid with a monohydric alcohol, or an ester of a b -chloropropionic acid with a monohydric alcohol, in the presence of an acidic condensing agent. Specified diarylamines are phenyl-a - or b -naphthylamine, p-hydroxy diphenylamine, p-amino, p-chloro or p-isopropoxy diphenylamine, phenyl-p-xenylamine, dinaphthylamine and dixenylamine. The esters of acrylic and b -chloropropionic acids specified include the alkyl, e.g. methyl, ethyl, propyl, butyl, dodecyl, alkenyl, substituted alkyl, e.g. chloromethyl, bromomethyl, b -ethoxyethyl, benzyl, and heterocyclic esters, e.g. furfuryl, and cyclohexyl and cyclobutyl. Temperatures in the range 30-175 DEG C., preferably 50-100 DEG C., may be used, with a ratio preferably of 2 mols. of amine to 1 mol. of ester. Specified catalysts are hydrochloric acid, phosphoric acid, sulphuric acid, sodium bisulphate, zinc chloride, aluminium chloride, stannic chloride, boron trifluoride and hydrogen fluoride. Preferred procedures include the use of solvents and diluents such as tetrachloroethane and other chlorinated hydrocarbons, ether, acetone, and toluene. The esters may be hydrolysed to give b -(N,N-diaryl), amino propionic acids. In the examples: (1) ethyl b -chloropropionate is added to molten diphenylamine and aluminium chloride to give ethyl b -(N,N-diphenyl)-amino propionate, also prepared (2) in a similar way from ethyl acrylate and diphenylamine. The Specification as open to inspection under Sect. 91 comprises also the statement that the amines dianilino-diphenylmethane and anilinodiphenylene oxide, and the catalysts iodine and ammonium bromide may be employed in the reaction. This subject-matter does not appear in the Specification as accepted.ALSO:A b -(N, N-diaryl), aminopropionic acid ester is used in kerosene solution for killing weeds. The aryl groups may be phenyl or naphthyl and may be substituted, e.g. by chloro, amino, hydroxy or isopropoxy groups, and the esterifying group is aliphatic, which may be substituted, e.g. by chloride, bromine, or ethoxy, aralkyl, or a heterocyclic radical, e.g. tetrahydrofurfuryl.ALSO:A b -(N, N-diaryl), aminopropionic acid ester is used in an aqueous suspension with sodium lauryl sulphate as a plant stimulant and hormone, e.g. for yew cuttings. The aryl group may be phenyl or naphthyl and may be substituted, e.g. by chloro, amino, hydroxy or isopropoxy groups, and the esterifying group is aliphatic, which may be substituted, e.g. by chlorine, bromine or ethoxy, aralkyl, or heterocyclic e.g. tetrahydrofurfuryl, radicals.