Patent GB-811130-A (GB)
Title: Improvements in and relating to n-acylated benzylamino phenols
IPC: C07C233/16
Filed: 1956-07-06
Abstract: The invention comprises compounds of the formula <FORM:0811130/IV (b)/1> (wherein RCO is an aliphatic, iso-cyclic or isocyclic-aliphatic acyl group which may be substituted in the radical R by halogen, hydroxy, alkoxy, alkanoyloxy, aralkoxy, aryloxy, arylmercapto or alkylmercapto groups), and their preparation by reacting one mol. of the acid RCOOH or a halide, anhydride or mixed anhydride, acyl cyanide, azide, alkyl ester or cyanomethyl ester thereof or one mol. of ketene with one mol. of the appropriate secondary amine. An acid-binding or condensing agent may be added if necessary. When an acid halide is used an inert organic solvent, e.g. a benzene hydrocarbon or a halogenated hydrocarbon, is advantageously added, and the acid-binding agent here may be a second mol. of the secondary amine or a tertiary organic base such as pyridine, dimethylaniline or a trialkylamine.  Such a base can also serve as the solvent.  For acylation with anhydrides a suitable solvent is glacial acetic acid and a suitable condensing agent sodium acetate. In examples: (1) N - (p1-hydroxybenzyl)-p-amino phenol (prepared by reduction of the condensation product of p-aminophenol and p-hydroxy-benzaldehyde) is acylated at room temperature with acetic anhydride in presence of acetic acid and sodium acetate; (2) the starting material of (1) is benzoylated with benzoyl chloride in chloroform; (3) N - (p1 - hydroxybenzyl) - N - (p - hydroxyphenyl) - dibutylacetamide is similarly prepared, the reactants being refluxed in chloroform in presence of pyridine.  Reference is also made to the following compounds: N-(p1-hydroxybenzyl) - N - (p - hydroxyphenyl) - 4 - chlorobenzamide, -2-hydroxy-benzamide, -phenoxyacetamide, -cinnamic acid amide, -b -phenylpropionamide, -gamma-phenylmercapto-butyramide, -caproic acid amide, -a -cyclohepten-(1)-ylbutyramide, -a -ethyl thiopropionamide, -4-iso-propoxy-benzamide, -iso-butyramide, -2-acetyloxy-benzamide, -2-methyl-benzamide, -4-benzyloxy-benzamide, -stearylamide, -3 : 4 : 5-trimethoxy - benzamide, - 4 - hydroxy - benzamide, -4 - t - butyl - benzamide, -4 - n - butoxybenzamide, - acetyloxy - acetamide and - 3 : 4-dimethyl - benzamide; N - (p1 - hydroxybenzyl) - N - (o - hydroxy - phenyl) - benzamide, dibutylacetamide, - phenylacetamide, - acetamide and -butyramide; and N-(o1-hydroxybenzyl) - N - (p - hydroxy - phenyl) - benzamide, acetamide, -dibutylacetamide, -isobutyramide and -acetyloxyacetamide.  A list of further acylating agents derived from the following additional acids is also given: propionic, valeric, isovaleric, capric, enanthic, pelargonic, lauric, methyl-ethyl-acetic, diethyl-acetic, di-n-butyl-acetic, di-iso-butyl-acetic, pivalic, crotonic, dimethylacrylic, undecylenic, oleic, sorbic, ethoxy-acetic, n-butoxy-acetic, acetyl-lactic, methyl - mercapto - acetic, cyclopropanecarboxylic, cyclohexane - carboxylic, a  - cyclohexen - (1) - yl - propionic, 2 - chloro - benzoic, 4 - bromo - benzoic m - and p - toluic, anisic, 4 - methyl - mercapto - benzoic, veratric, vanillic, isovanillic, gallic, a - and b -naphthoic, 4-chlorocinnamic, acetyl-mandelic, o- and p-cresoxy-acetic, phenyl-mercapto-acetic, b -naphthyl-acetic and b -naphthoxy-acetic acids.