GB493339A - Manufacture of aromatic amino-compounds - Google Patents

Abstract

Amines are obtained by the reduction of nitrophenols (or their ethers) substituted in the nucleus by one or more aliphatic hydrocarbon radicles containing in all more than seven carbon atoms, at least one aliphatic radicle having more than three carbon atoms; the nitrophenols or their ethers may contain additional substituents such as carboxylic groups. Specified starting materials are the nitro derivatives of isooctylphenols, p-(a , a , g , g -tetramethylbutyl) phenol, isodecyl-o-cresols, diisobutyl-phenols, isononylanisoles and isooctylsalicylic acids; nitro derivatives of corresponding polynuclear compounds; e.g. of isooctyl-a -naphthols, may also be used. Reduction may be effected with hydrogen in the presence of a hydrogenation catalyst. In the examples: (1) p - isooctyl - o - nitroanisole is treated in alcohol with hydrogen at 40-50 DEG C. and 80-90 atm. pressure in the presence of a nickel catalyst; (2) p-isooctyl-o, o1-dinitroanisole containing a subordinate proportion of mononitro compound is reduced as described in example 1; the products may be separated by fractional distillation; (3) mononitroisooctylphenol is reduced as described in example 1.ALSO:Amines are obtained by the reduction of nitrophenols (or their ethers) substituted in the nucleus by one or more aliphatic hydrocarbon radicles containing in all more than seven carbon atoms, at least one aliphatic radicle having more than three carbon atoms; the nitrophenols or their ethers may contain additional substituents, such as carboxylic groups. Specified starting materials are the nitro derivatives of isooctylphenols, p-(a , a , g , g -tetramethylbutyl)phenol, isodecyl-o-cresols, diisobutylphenols, isononylanisoles, and isooctylsalicylic acids; nitro derivatives of corresponding polynuclear compounds, e.g. of isooctyl-a -naphthols, may also be used; the preparation of such starting materials is described in Specification 493,294. Reduction may be effected with hydrogen in the presence of a hydrogenation catalyst, or by means of tin or iron and hydrochloric acid. In the examples: (1) p - isooctyl-o-nitroanisole is treated in alcohol with hydrogen at 40-50 DEG C. and 80-90 atm. pressure in the presence of a nickel catalyst; (2) p-isooctyl-o, o1-dinitroanisole containing a subordinate proportion of mononitro compound is reduced as in example 1; the products may be separated by fractional distillation; (3) mononitroisooctylphenol is reduced as described in example 1, or with tin and hydrochloric acid.