Patent GB-362449-A (GB)
Title: Improvements in or relating to the manufacture of vat dyestuffs of the benzanthrone series
IPC: C09B5/40
Filed: 1930-09-02
Abstract: Dyestuffs of the benzanthrone series are prepared by heating 2-(Bz1-nitrobenzanthrony)-1<1>-aminoanthraquinone or a derivative thereof having a free 2<1>- position, to an elevated temperature with or without the addition of an organic diluent, such as nitrobenzene, nitronaphthalene, naphthalene or benzophenone.  Alternatively the same products are obtained in a single operation and without isolation of the above starting materials by heating together to an elevated temperature a mixture of Bz1-nitro-2-chlorbenzanthrone or a halogenated derivative thereof and an a -aminoanthraquinone in equimolecular proportions, advantageously in the presence of a high boiling diluent and with the addition of an acid-binding agent and a catalyst, such as copper or a copper compound.  The nitro group is split off and the same dyestuffs obtained as by the processes of Specifications 305,679, [Class 2 (iii), Dyes &c.], 341,400, and 348,706, starting from a 1-(2-benzanthronylamino)-anthraquinone. According to examples (1) the condensation product of Bz1-nitro-2-chlorbenzanthrone (1 mol.) and 1-aminoanthraquinone (1 mol.) is boiled in nitrobenzene (or nitronaphthalene, naphthalene and benzophenone may be used); or the product is heated alone to 300-330 DEG ; or the two components Bz1-nitro-2-chlorbenzanthrone and 1-aminoanthraquinone are heated together in a -nitronaphthalene with sodium carbonate and copper bronze (or copper oxide, or other copper compound); the product is purified by dissolving in sulphuric acid and the resulting acid salt decomposed by water; it dyes dark-green shades on cotton: (2) the condensation product of Bz1-nitro-2 : 7-dichlorobenzanthrone (1 mol.) and 1-aminoanthraquinone (1 mol.) is boiled in 1 : 4-dichloro-2-nitrobenzene; or Bz1-nitro-2 : 7-dichlorbenzanthrone (1 mol.) and 1-aminoanthraquinone (1 mol.) are heated together in a -nitronaphthalene with sodium carbonate and copper bronze; the product dyes green shades: (3) a similar dyestuff to that of (2) is obtained either by heating the condensation product of Bz1-nitro-2 : 6-dichlorbenzanthrone (1 mol.) and 1-aminoanthraquinone (1 mol.) to higher temperatures, or by heating the components together as above: (4) the condensation product of Bz1-nitro-2-chlorobenzanthrone (1 mol.) and 1 : 6-diaminoanthraquinone (1 mol.) is boiled in a -nitronaphthalene, or Bz1-nitro-2-chlorbenzanthrone (1 mol.) and 1 : 6-diaminoanthraquinone (1 mol.) are boiled in nitrobenzene in presence of sodium carbonate and copper bronze; the product dyes greyish-blue shades: (5) similar dyestuffs to (4) are obtained by the processes thereof applied to Bz1-nitro-2 : 6-dichlorbenzanthrone or Bz1-nitro-2 : 7-dichlorbenzanthrone (instead of Bz1-nitro-2-chlorbenzanthrone) and 1 : 6- or other suitable diaminoanthraquinone: (6) the condensation product of Bz1-nitro-2-chlorbenzanthrone (1 mol.) and 1-amino-4- (or -5-) benzoylaminoanthraquinone (1 mol.) is boiled in naphthalene; or Bz1-nitro-2-chlorbenzanthrone (1 mol.) and 1-amino-4- (or -5-) benzoylaminoanthraquinone (1 mol.) are heated at 210 DEG -215 DEG  in naphthalene in presence of sodium carbonate and copper bronze; the products dye olive-green shades, and similar dyestuffs are obtained if Bz1-nitro-2-chlorbenzanthrone is replaced by Bz1-nitro-2 : 6- or -2 : 7-dichlorbenzanthrone.  Bz1-Nitro-2 : 6- and -2 : 7-dichlorbenzanthrones are prepared by nitrating 2 : 6- and 2 : 7-dichlorbenzanthrones respectively.