Preparation of dyes derived from Eriochrome Red B and Acid Alizarin Violet N soluble in organic solvents

Article abstract of DOI:10.1002/recl.19931121007

Both hydroxy groups of Eriochrome Red B are protected by acetylation and the sulfonic acid group is converted to the sulfonyl chloride with phosphorus pentachloride.Reaction with dibutylamine or N-butylbenzeneethanamine followed by the deprotection gives