PROCESS FOR THE MANUFACTURE OF BASIC OXAZINE DYESTUFFS

摘要

There is described a one-pot process for preparing basic oxazine dyes of the formula (1) IMAGE where the symbols are each as defined in Claim 1, by nitrosating a compound of the formula (2) IMAGE in a cyclic ether, sulpholane or alkyl-substituted amide in the presence of an acid HX and optionally in mixture with water or an aliphatic alcohol, at room temperature, and condensing the resulting suspension containing the nitroso compound without intermediate isolation thereof with aminophenol of the formula (3) IMAGE at elevated temperature. The oxazine dyes obtained are suitable for dyeing or printing for example mordanted cellulose fibres, silk, leather or synthetic fibres, in particular polyacrylonitrile.