A new method for the preparation of 1-amino-2,4-dibromoanthra-9,10-quinone

1-Amino-2,4-dibromoanthra-9,10-quinone is an important intermediate in the preparation of anthra-9,10-quinone dyes, manufacture of which has been patented. Various methods of brominating aminoanthraquinone have been studied extensively by our research group. It is to be noted that all the procedures involving the bromination of the aminoanthraquinone have been presented to give mixture of isomers and purification of isomers is more difficult, and doesn't readily lend itself to economic separation. This paper presents a new procedure for brominating 1-aminoanthra-9,10-quinone to produce 1-amino-2,4-dibromoanthra-9,10-quinone in high yield and purity.