Manufacture of aromatic nitro-compounds

摘要

Phenolic compounds (or their ethers) containing one or more aliphatic hydrocarbon side chains containing in all more than seven carbon atoms, at least one side chain containing more than three carbon atoms, are nitrated to yield mono- or poly-nitro compounds useful as intermediates for dyes, textile assistants and pharmaceutical products. The phenolic compounds or ethers may contain additional substituents, such as carboxylic groups. In the examples: (1) p-isooctylanisole is nitrated at 5-15 DEG C. with a mixture of nitric and sulphuric acids to yield o-nitro-p-isooctylanisole; (2) p-isooctylanisole is treated at 0-10 DEG C. with nitric acid in glacial acetic acid; o.o1-dinitro-p-isooctylanisole is the main product; (3) isooctylphenol (from phenol and diisobutylene) is added as an alcoholic solution to a mixture of aqueous sodium nitrate and sulphuric acid kept at 25-30 DEG C.; a mononitro-isooctylphenol is obtained. Other specified starting materials are p-a , a , g , g -tetramethylbutylphenol, isododecyl-o-cresols, diisobutylphenols, isononylanisoles, isooctylsalicylic acids, and analogous polynuclear compounds having linked or fused nuclei, such as isooctyl-a -naphthols. The treatment of 1-methyl - 3 - methoxy - 4 : 6 - di - tert. - butylbenzene with a nitrating agent is disclaimed. The Specification as open to inspection under Sect. 91 covers generally the nitration of aromatic compounds having one or more aliphatic side chains containing in all more than seven carbon atoms, and specifies the following additional starting materials: diisobutylbenzenes, diisoamylbenzenes, isododecylbenzene, diisobutyltoluene, isohexylxylenes, diisobutylnaphthalenes, tetradecylnaphthalene, octadecylnaphthalene, decylphenanthrene, isooctylanthracene, and diisohexyldiphenyls, and derivatives of such compounds containing additional substituents, such as carboxylic groups. It describes also the reduction of the nitro compounds to the corresponding amino compounds, and states that this may be effected by catalytic hydrogenation or with tin or iron and hydrochloric acid. The following additional examples are given: (1) the product of example 1 above is treated in alcoholic solution with hydrogen in the presence of a nickel catalyst, this yielding o-amino-p-isooctylanisole; (2) the product of example 2 above is similarly reduced to yield o, o1-diamino-p-isooctylanisole and a minor proportion of o-amino-p-isooctylanisole; these products may be separated by fractional distillation; (3) the product of example 3 above is reduced with tin and hydrochloric acid to yield an aminoisooctylphenol; (4) isododecylbenzene is nitrated with a mixture of nitric and sulphuric acids to yield a mononitroisododecylbenzene, which is reduced with tin and hydrochloric acid to yield an isododecylaniline. This subject-matter does not appear in the Specification as accepted.