GB307926A - Manufacture of nitrogen-containing derivatives of the benzanthrone series - Google Patents

Abstract

307,926. I. G. Farbenindustrie Akt.- Ges. March 16, 1928, [Convention date]. Nitro- and amino dibenzpyrenequinones. - Dibenzpyrenequinones and their derivatives and substitution products are converted into nitro derivatives by treating with nitrating agents in the presence or absence of a diluent, such as nitrobenzene. The products are converted into amino derivatives by treating with reducing agents. such as sodium sulphide, phenylhydrazine or hydrosulphite : if the latter is used, the reduction may occur in the alkaline vat. In examples, (1) 3 : 4 : 8 : 9 dibenzpyrene-5 : 10-quinone is treated with nitric acid; the dinitro derivative obtained is reduced by alkali and hydrosulphite to an amino derivative and finally transferred into a carmine red vat which dyes cotton violet tints, (2) 3:4:8: 9-dibenzpyrene.-5 : 10-quinone is treated with a nitric acid-sulphuric acid mixture: the product is transformed into a dark violet amino derivative by boiling it with sodium sulphide, (3) dibrom-3 : 4: 8 : 9-dibenzpyrene-5 : 10- quinone is treated with concentrated nitric, acid, (4) 4 : 5 : 8 : 9-dibenzpyrene-3 : 10-quinone is treated with concentrated nitric acid, a dinitro derivative is obtained, which mav be reduced by phenylhydrazine to the diamino. derivative; the latter dyes cotton from an orange vat in greyish-blue tints, changed to dark brown on after-treating with a hypochlorite, and (5). monomethyl 4:5 : 8: 9 - dibenzpyrene - 3 : 10- quinone, obtainable by ring-closure of 2-ptoluvlbenzanthrone bv means of aluminium chloride (Specification 287,050), is treated with nitric acid; the product after reduction, dyes cotton in olive-green tints. The Specification as open to inspection under Sect. 91 (3) (a) states that the nitration may take place in the presence or absence of a diluent such as nitrobenzene, mono, di- or more highly nitrated products being obtained according to the conditions. In further examples, monitro derivatives of 3 : 4 : 8 : 9-dibenzpyrene 5 : 10-quinone and 4 : 5 : 8 : 9-dibenzpyrene-3-10-quinone are obtained by nitrating in nitrobenzene, and more highly nitrated products, including a trinitro- 4: 5 8: 9-dibenzpyrene-3 :10.quinone are also described. This subject-matter does not appear in the Specification as accepted.