|Named after||Otto Fischer
|Reaction type||Rearrangement reaction|
|RSC ontology ID|
This organic reaction was first described by the German chemist Otto Philipp Fischer (1852–1932 ) and Eduard Hepp (June 11, 1851 – June 18, 1917)  in 1886, and is of importance because para-NO secondary anilines cannot be prepared in a direct reaction.
The rearrangement reaction takes place by reacting the nitrosamine precursor with hydrochloric acid. The chemical yield is generally good under these conditions, but often much poorer if a different acid is used. The exact reaction mechanism is unknown but there is evidence suggesting an intramolecular reaction.
- Friedel–Crafts alkylation-like reactions: