An unusual substitution reaction of an aromatic sulfonic group based on 3-carbonyl-4-phenolsulfonic acid

Article abstract of DOI:10.1016/j.cclet.2013.04.016

An unusual substitution reaction of an aromatic sulfonic group based on 3-carbonyl-4-phenolsulfonic acid was discovered in a diazo-coupling process. The reaction occurred under mild reaction conditions (pH 8.0-9.0, 0-5 C, solvent: water) within a short reaction time (1 h). A plausible substitution reaction mechanism by phenol-ketone resonance was proposed.