Bromine → 4-Bromo-5-hydroxy-1-[(1-methylethyl)amino]-9,10-anthracenedione

Participants

Reaction Steps

If the 12.9 parts of 1-isopropylamino-5-hydroxy-anthraquinone obtained in Example 3 are dissolved in 130 parts of 30% strength hydrochloric acid, 9.5 parts of bromine are added dropwise at room temperature, and the mixture is further stirred at room temperature or at elevated temperature (up to 40°) until at most 5% of 1-isopropylamino-5-hydroxy-anthraquinone can still be detected chromatographically in a sample which has been withdrawn, then 15.95 parts of 1-isopropylamino-5-hydroxy-4-bromanthraquinone are obtained after pouring out into 300 parts of water and further working up as described in (a). The quality of this product is only slightly better than that of the product obtained according to Example 4a.

Provenance & Evidence