Process for the manufacture of aromatic sulfonic acid halides

摘要

An improved process for the manufacture of aromatic sulfonic acid halides from aromatic diazonium compounds, wherein aromatic diazonium compounds are reacted in a strongly hydrochloric or hydrobromic solution in the presence of copper or copper compounds with an alkali metal hydrogeno-sulfite, which avoids the use of liquid or gaseous sulfur dioxide and of organic solvents according to known processes which makes the process, if carried out on a technical scale, expensive and strongly contaminates the waste water.