GB606008A - Process for the manufacture of halogenated naphthoquinoneimides - Google Patents

Abstract

Halogenated naphthoquinoneimides are prepared by treating a naphthoquinoneimide with a halogenating agent, preferably in a solvent in the presence of a halogenation catalyst (e.g. iodine and iron and antimony halides) and under the influence of ultra-violet light. The naphthoquinoneimides can be obtained by the treatment of a : a -dinitronaphthalenes with reducing agents and the halogenation may be carried out during, or immediately after; the formation of the naphthoquinoneimide. Preferred starting compounds are the 1 : 5- and 1 : 8-dinitronaphtholenes and their b -substituted derivatives such as halogen, sulphonic acid, hydroxy, alkoxy and acylamino derivatives, which are reduced to the imides by sulphur sesquioxide in the presence of sulphuric acid. Halogenation may be carried out at temperatures ranging from 40-200 DEG C. according to the degree of halogenation required. Tri- and tetra-halides are preferably prepared by halogenating the dihalides. The products may be used as dyestuffs or intermediates therefor. In examples: (1) 5-amino-8-hydroxy-1 : 4-naphthoquinoneimide is treated with bromine in glacial acetic acid using iodine as a catalyst to give a dibromo compound; (2) 1 : 5-dinitronaphthalene is reduced with sulphur in a mixture of sulphuric acid and oleum and the resultant solution is treated with bromine in the presence of iodine; (3) 1 : 5-dinitronaphthalene is reduced with tin and sulphuric acid and the product is brominated as in (2); (4) 1 : 5-dinitronaphthalene is reduced with sulphur in sulphuric acid, a trace of iodine is added and chlorine is passed into the solution under irradiation with ultra-violet light; (5) a mixture of 1 : 5- and 1 : 8-dinitronaphthalenes is treated as in (2); (6) 1 : 8-dinitronaphthalene is similarly treated; (7) 1 : 8-dinitronaphthalene is treated as in (3); (8) 1 : 5-dinitronaphthalene is reduced with sulphur in sulphuric acid and oleum, then chlorinated with sulphuryl chloride and a trace of iodine; (9) a mixture of 2-chloro-1 : 5- and -1 : 8-dinitronaphthalenes is treated as in (2); (10) the mixture of the bromonaphthoquinoneimides obtained from (2) is brominated in the presence of iodine and in ultra-violet light to give a mixture of the tri- and tetrabromo-compounds; (11) the process of (10) is repeated under milder conditions giving the di- and tribromo derivatives; and (12) the process of (10) and (11) is carried out under more vigorous conditions to give substantially the tetrabromo compound.ALSO:Halogenated naphthoquinoneimides are prepared by treating a naphthoquinoneimide with a halogenating agent, preferably in a solvent in the presence of a halogenation catalyst (e.g. iodine and iron and antimony halides) and under the influence of ultra-violet light. The naphthoquinoneimides can be obtained by the treatment of a : a -dinitronaphthalenes with reducing agents and the halogenation may be carried out during, or immediately after, the formation of the naphthoquinoneimide. Preferred starting compounds are the 1 : 5- and 1 : 8-dinitronaphthalenes and their b -substituted derivatives such as halogen, sulphonic acid, hydroxy, alkoxy and acylamino derivatives which are reduced to the imides by sulphur sesquioxide in the presence of sulphuric acid. Halogenation may be carried out at temperatures ranging from 40-200 DEG C. according to the degree of halogenation required. Tri- and tetra-halides are preferably prepared by halogenating the halides. The products may be used as dyestuffs or intermediates therefor. In examples: (1) 5-amino-8-hydroxy-1 : 4-naphthoquineneimide is treated with bromine in glacial acetic acid using iodine as a catalyst to give a dibromo compound; (2) 1 : 5-dinitronaphthalene is reduced with sulphur in a mixture of sulphuric acid and oleum and the resultant solution is treated with bromine in the presence of iodine; (3) 1 : 5-dinitronaphthalene is reduced with tin and sulphuric acid and the product is brominated as in (2); (4) 1 : 5-dinitronaphthalene is reduced with sulphur in sulphuric acid, a trace of iodine is added and chlorine is passed into the solution under irradiation with ultra-violet light; (5) a mixture of 1 : 5- and 1 : 8-dinitronaphthalenes is treated as in (2); (6) 1 : 8-dinitronaphthalene is similarly treated; (7) 1 : 8-dinitronaphthalene is treated as in (3); (8) 1 : 5-dinitronaphthalene is reduced with sulphur in sulphuric acid and oleum, then chlorinated with sulphuryl chloride and a trace of iodine; (9) a mixture of 2-chloro-1 : 5- and 1 : 8-dinitronaphthalenes is treated as in (2); (10) the mixture of p the bromonaphthoquinone imides obtained from (2) is brominated in the presence of iodine and in ultra-violet light to give a mixture of the tri- and tetrabromo-compounds; (11) the process of (10) is repeated under milder conditions giving the di- and tribromo derivatives; and (12) the process of (10) and (11) is carried out under more vigorous conditions to give substantially the tetrabromo compound.