Patent GB-415749-A (GB)
Title: Manufacture of dyestuffs
IPC: C09B19/02
Filed: 1933-01-27
Abstract: Oxazines are obtained by (1) heating a 2 : 6 - di - (aryl - acylaminoarylamino or -acyl - carbazoylamino) - 3 : 6 - di - halogen, dialkyl, or diaryl-1 : 4-benzoquinone which may also be unsubstituted in positions 3 and 6, either alone or in presence of a solvent of high boiling point, preferably with the addition of a metal chloride, an oxidizing agent, or both, or (2) heating at about 150--300 DEG  C. a 1 : 4-benzoquinone which may contain halogen, alkyl or aryl as substituent with an aryl-acylaminoarylamine or an acylcarbazoleamine, under the above conditions and where hydrochloric acid is eliminated, in presence of an acid-binding agent, or (3) by heating 2 : 5 di-aryl-aminoarylamino or -carbazoylamino) - 3 : 6 - dihalogen, dialkyl or diaryl-1 : 4-benzoquinones or which may be unsubstituted in positions 3 and 6 in presence of acylating agents under the above conditions or by acylating after the oxazine condensation.  In all cases at least one ortho-position to the NH-group in the aryl nucleus next the benzoquinone nucleus must be free; the following high-boiling solvents and/or oxidizing agents are specified: nitrobenzene, trichlorobenzene, potassium ferricyanide, pyrolusite, ferric chloride, alkali metal nitrates.  The above-mentioned acylated benzoquinone compounds are obtained by introducing acyl groups at a suitable phase in the preparation of the condensation products from 1 : 4-benzoquinone, or substitution products thereof with aminodiarylamines or aminocarbazoles; as acylating agents are specified sulphonic and carboxylic chlorides or anhydrides of the aliphatic or aromatic series, carbamic acid chloride, carbonyl chloride, and agents yielding it.  The products are useful as pigment dyes, the acyl group having the effect of producing clear violet shades, more reddish than those of the parent case.  The dyes may be converted by sulphonation by customary methods into dyes suitable for animal, vegetable and viscose fibres.  According to examples, (1) the following compounds are heated in nitrobenzene: 2 : 5-di-(N-benzoyl-carbazoyl-3-amino)-3 : 6-dichloro-1 : 4-benzoquinone (obtainable by reducing 3-nitro-N-benzoylcarbazole and condensing with 2 : 3 : 5 : 6-tetrachloro-1 : 4-benzoquinone) the corresponding N-acetyl compound obtained analogously to the above, the corresponding N - p - toluenesulphonyl compound obtainable from N-p-toluenesulphonylcarbazole by nitration, reduction and condensation with the above benzoquinone compound, the corresponding N-diphenylcarbaminyl compound obtained by treating diphenylamine with phosgene, acylating 3-nitro-carbazole with the product, reducing, and condensing with the above benzoquinone derivative, and 2 : 5-di-(N-p-toluenesulphonyl - carbazoyl - 3<1> - amino) - 6 - methyl - 1 : 4 - benzoquinone (obtainable by condensing 2-methyl-1 : 4-benzoquinone with 3-amino-N-p-toluenesulphonylcarbazole); (2) the compound obtained by condensing 2 : 3 : 5 : 6-tetrachloro-1 : 4-benzoquinone with 3-aminocarbazole is acylated and condensed with p-toluenesulphonic chloride; (3) the compounds obtained by treating 2 : 3 : 5 : 6-tetrachloro-1 : 4-benzoquinone with 3-aminocarbazole and 3-amino-N-benzoylcarbazole are respectively acylated and condensed with benzoyl chloride in benzotrichloride, or condensed with trichlorobenzene and potassium nitrate or similar agents; (4) 2 : 3 : 5 : 6-tetrachloro-1 : 4-benzoquinone is condensed with di-(N-3-aminocarbazole)-carbonyl (obtained by reducing the product of condensation of 3-nitrocarbazole and carbonyl chloride.  The oxazine products on sulphonation give blue to violet dyes. Samples have been furnished under Sect. 2 (5) of the Acts of products obtained, (1) by heating the condensation product from N - benzoyl - 4 - aminodiphenylamine and 2 : 3 : 5 : 6-tetrachloro-1 : 4-benzoquinone in nitrobenzene; (2) and (3) by treating the condensation products from 1 mol. of 2 : 3 : 5 : 6-tetrachloro-1 : 4-benzoquinone and 2 mols. of 3-aminocarbazole or 2 mols. of 4-amino-4<1>-methoxy-diphenylamine with benzoyl chloride in nitrobenzene; (4), (5) and (6) by sulphonating the said three dyes. Specification 8886/12, [Class 2 (iii)], is referred to.  The Specification as open to inspection under Sect. 91 also contains examples of the condensation in nitro-benzene and sulphonation of the product obtained by condensing 2 : 6-dichloro-1 : 4-benzoquinone with 3-amino-N-acetylcarbazole, and the benzoylation of the products obtained by condensing 1 : 4-benzoquinone and 2-mols. of 3-amino-carbazole and by condensing 2 : 3 : 5 : 6-tetrabromo-1 : 4-benzoquinone and 2 mols. of 3-aminocarbazole, and refers to the condensation of alkyl, and aryl 1 : 4-benzoquinones with amino-N-acylphenylnaphthylamines, amino-N-acyl-dinaphthylamines, amino - N - acyl - naphthylphenylamines and amino-N-acyl-carbazoles, especially 3 - amino - N - acetyl 5 : 6 - benzocarbazole obtainable by acetylating and reducing 2<1>-nitro-1 : 2-naphthocarbazole. This subject-matter does not appear in the Specification as accepted.