GB249147A - Manufacture of halogen-dibenzpyrenequinones - Google Patents

Abstract

249,147. I. G. Farbenindustrie Akt.- Ges., (Assignees of Farbwerke vorm. Meister, Lucius, & Briining). March 14, 1925, [Convention date]. Halogen dibenzopyrenequinones are obtained by treating 1 : 5-dibenzoyl-2 : 6-dioxynaphthalene (see Specification 248,791), or its derivatives substituted in the benzoyl residues, with a phosphorus halide whereby halogen is substituted for hydroxyl and ring closure effected so as to yield an intermediate product which on heating with sulphuric acid yields dihalogen-dibenzopyrenequinones. The products dye cotton in yellow shades from a red vat. According to an example 2 : 6-dihydroxy-1 : 5-dibenzoylnaphthalene is heated with phosphorus pentachloride in chlorbenzene; the intermediate product separating is then heated with sulphuric acid of 66 per cent strength to obtain 1 : 6-dichlor- 3:4:8:9-dibenzopyrene - 5 : 10-quinone. In place of phosphorus pentachloride phosphorus pentabromide or a mixture of phosphorus pentachloride and oxychloride may be employed. The Specification as open to inspection under Sect. 91 (3) (a) extends to the treatment of 1: 5- dibenzoyl-2: 6-dioxynaphthalenes other than those substituted in the benzoyl residues and to the use of agents other than phosphorus halides for effecting exchange of OH for halogen. This subject-matter does not appear in the Specification as accepted.