GB882063A - Silane azo dyestuffs and a process for the preparation thereof - Google Patents

Abstract

The invention comprises silane azo dyestuffs of the formula <FORM:0882063/IV (a)/1> where R is an aryl or substituted aryl radical, Ar is an arylene or substituted arylene radical, X is hydrogen or an alkyl radical, Y is an alkyl, aryl, alkoxy or aryloxy radical, and a is an integer of at least 3. They are prepared by coupling the diazonium salt of an aromatic primary amine with an arylaminoalkylsilane, the latter being disclosed in Specification 882,052. The aryl group R may be phenyl, naphthyl or anthraquinone, which may be substituted by chlorine, hydroxy, methoxy, alkyl, sulpho, sulphonic acid amide, arylazo, phenyl, nitro or acylamino radicals. The arylene radical may be phenylene or naphthylene, and may be substituted by alkyl, alkoxy, nitro, halogen or sulpho radicals. When hydrolysable silanes are used, the reaction is effected in an anhydrous medium, e.g. dioxane, acetic acid, dimethylformamide, 2-methoxyethanol and ethylene glycol. The products may be hydrolyzed to polysiloxanes as described in Specification 882,066. Non-hydrolyzable silanes may be prepared in aqueous or non-aqueous media. Metallic complexes of the dyestuffs can also be produced, e.g. dianisidine tetrazo is coupled in acidic medium with one equivalent of an arylaminoalkylsilane and then in alkaline medium with 8-acetylamino-1-hydroxynaphthalene -3,6-disulphonic acid to give the dyestuff <FORM:0882063/IV (a)/2> which can be treated with salts of Cr, Mn, Fe, Co, Ni, Cu, Pb, Sn and Zn to form the metal complexes. The carboxyl and sulphonyl containing dyestuffs may be either in the free acid or in the salt form. Examples describe the preparation of the red dye <FORM:0882063/IV (a)/3> from the diazonium salt of anthranilic acid and N-methyl-N-(g -trimethylsilylpropyl)aniline; and the red dye <FORM:0882063/IV (a)/4> from the diazonium salt of p-nitroaniline and N-methyl-N-(g -triethoxysilylpropyl)aniline.